CN114805406A

CN114805406A - Organic electroluminescent device and polycyclic compound for organic electroluminescent device

Info

Publication number: CN114805406A
Application number: CN202210027827.6A
Authority: CN
Inventors: 古江龙侑平; 桑原博一; 杉田吉朗; 须崎裕司; 青木雄真
Original assignee: Samsung Display Co Ltd
Current assignee: Samsung Display Co Ltd
Priority date: 2021-01-19
Filing date: 2022-01-11
Publication date: 2022-07-29
Also published as: KR20220105577A

Abstract

The present application relates to an organic electroluminescent device including a first electrode, a hole transport region disposed on the first electrode, an emission layer disposed on the hole transport region, an electron transport region disposed on the emission layer, and a second electrode disposed on the electron transport region. The emitting layer comprises1, thereby exhibiting high emission efficiency. [ formula 1]

Description

Organic electroluminescent device and polycyclic compound for organic electroluminescent device

Cross Reference to Related Applications

This application claims priority and benefit of korean patent application No. 10-2021-0007287, filed on 19.1.2021 to the korean intellectual property office, the entire contents of which are incorporated herein by reference.

Technical Field

The present disclosure relates to an organic electroluminescent device and a polycyclic compound for the organic electroluminescent device.

Background

Active development of an organic electroluminescent display as an image display is continuously proceeding. The organic electroluminescent display is different from a liquid crystal display and is a so-called self-luminous display in which holes and electrons injected from a first electrode and a second electrode, respectively, are recombined in an emission layer, so that a light-emitting material including an organic compound in the emission layer emits light to realize display.

In the application of the organic electroluminescent device to an image display, there are demands for reducing a driving voltage of the organic electroluminescent device, increasing emission efficiency of the organic electroluminescent device, and increasing a lifetime of the organic electroluminescent device, and continuous development of materials for the organic electroluminescent device capable of stably realizing such characteristics is required.

It should be appreciated that this background section is intended in part to provide a useful background for understanding the technology. However, this background section may also include concepts, concepts or insights that are not known or understood by those of ordinary skill in the relevant art prior to the filing date of the corresponding effective application of the subject matter disclosed herein.

Disclosure of Invention

The present disclosure provides an organic electroluminescent device having high efficiency and a polycyclic compound included in an emission layer of the organic electroluminescent device.

Embodiments provide polycyclic compounds represented by the following formula 1.

[ formula 1]

In formula 1, X ₁ And X ₂ May each independently be O, S or N (R) ₇ ) E and f may each independently be an integer of 0 to 4, g may be an integer of 0 to 2, h may be an integer of 0 to 3, R ₁ To R ₄ 、R _5-1 To R _5-3 And R _6-1 To R _6-3 May each independently be a hydrogen atom, a deuterium atom, a halogen atom, a nitro group, a cyano group, a hydroxyl group, a substituted or unsubstituted amine group, a substituted or unsubstituted thiol group, a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted aryl group having 6 to 30 ring-forming carbon atoms, or a substituted or unsubstituted heteroaryl group having 2 to 30 ring-forming carbon atoms, or may be combined with an adjacent group to form a ring, R ₇ May be a hydrogen atom, a deuterium atom, a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted aryl group having 6 to 30 ring-forming carbon atoms, or a substituted or unsubstituted heteroaryl group having 2 to 30 ring-forming carbon atoms, or may be bonded to an adjacent group to form a ring, and Y ₁ And Y ₂ May each independently be a hydrogen atom, a deuterium atom, a substituted or unsubstituted alkyl group having 6 to 20 carbon atoms, a substituted or unsubstituted aryl group having 6 to 30 ring-forming carbon atoms, or a substituted or unsubstituted heteroaryl group having 2 to 30 ring-forming carbon atoms, and Y ₁ And Y ₂ At least one of which may be a substituted or unsubstituted alkyl group having 6 to 20 carbon atoms, a substituted or unsubstituted aryl group having 6 to 30 ring-forming carbon atoms, or a substituted or unsubstituted heteroaryl group having 2 to 30 ring-forming carbon atoms.

In the embodimentIn, X ₁ And X ₂ May be N (R) ₇ ) And R is ₇ May be a substituted or unsubstituted aryl group having 6 to 30 ring-forming carbon atoms or a substituted or unsubstituted heteroaryl group having 2 to 30 ring-forming carbon atoms.

In embodiments, the polycyclic compound represented by formula 1 may be represented by any one of the following formulas 2-1 to 2-5.

[ formula 2-1]

[ formula 2-2]

[ formulas 2-3]

[ formulae 2 to 4]

[ formulas 2 to 5]

In formulae 2-1 to 2-5, Ar _1-1 And Ar _1-2 May each independently be a substituted or unsubstituted aryl group having 6 to 30 ring-forming carbon atoms, or a substituted or unsubstituted heteroaryl group having 2 to 30 ring-forming carbon atoms, and R ₁ To R ₄ 、R _5-1 To R _5-3 、R _6-1 To R _6-3 、Y ₁ 、Y ₂ And e to h may be the same as defined with respect to formula 1.

In embodiments, Ar _1-1 And Ar _1-2 May each independently be a group represented by any one of the following formulas 5-1 to 5-3.

In the formulae 5-1 to 5-3, R _a1 To R _a5 May each independently be a hydrogen atom, a deuterium atom, a halogen atom, a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted aryl group having 6 to 30 ring-forming carbon atoms, or a substituted or unsubstituted heteroaryl group having 2 to 30 ring-forming carbon atoms, m1, m3, and m5 may each independently be an integer of 0 to 5, m2 may be an integer of 0 to 9, m4 may be an integer of 0 to 3, and represents a binding site to an adjacent atom.

In embodiments, R _5-1 To R _5-3 And R _6-1 To R _6-3 May be a substituted amine group.

In embodiments, the polycyclic compound represented by formula 1 may be represented by formula 3-1 or formula 3-2 below.

[ formula 3-1]

[ formula 3-2]

In formulae 3-1 and 3-2, Ar _3-1 、Ar _3-2 、Ar _4-1 And Ar _4-2 May each independently be a substituted or unsubstituted aryl group having 6 to 30 ring-forming carbon atoms, and X ₁ 、X ₂ 、R ₁ To R ₄ 、R _5-1 To R _5-3 、R _6-1 To R _6-3 、Y ₁ 、Y ₂ And e to h may be the same as defined with respect to formula 1.

In embodiments, the polycyclic compound represented by formula 1 may be represented by formula 4 below.

[ formula 4]

In formula 4, Ar _3-1 、Ar _3-2 、Ar _4-1 And Ar _4-2 May each independently be a substituted or unsubstituted aryl group having 6 to 30 ring-forming carbon atoms, and X ₁ 、X ₂ 、R ₁ To R ₄ 、R _5-1 、R _5-3 、R _6-1 、R _6-3 、Y ₁ 、Y ₂ And e to h may be the same as defined with respect to formula 1.

In embodiments, Ar _3-1 、Ar _3-2 、Ar _4-1 And Ar _4-2 May each independently be a substituted or unsubstituted aryl group having from 6 to 18 ring-forming carbon atoms.

In embodiments, the polycyclic compound represented by formula 1 may be any one selected from compound group 1.

In an embodiment, an organic electroluminescent device may include a first electrode, a hole transport region disposed on the first electrode, an emission layer disposed on the hole transport region, an electron transport region disposed on the emission layer, and a second electrode disposed on the electron transport region, wherein the emission layer may include the polycyclic compound of an embodiment.

In embodiments, the emissive layer may emit delayed fluorescence.

In embodiments, the emission layer may be a delayed fluorescence emission layer including a first compound and a second compound, and the first compound may include the polycyclic compound.

In embodiments, the emission layer may be a thermally activated delayed fluorescence emission layer that emits light having a wavelength of about 430nm to about 480 nm.

Drawings

The accompanying drawings are included to provide a further understanding of the embodiments, and are incorporated in and constitute a part of this specification. The drawings illustrate embodiments of the disclosure and their principles. The above and other aspects and features of the present disclosure will become more apparent by describing in detail embodiments thereof with reference to the attached drawings in which:

fig. 1 is a plan view illustrating a display apparatus according to an embodiment;

fig. 2 is a schematic cross-sectional view illustrating a display apparatus according to an embodiment;

fig. 3 is a schematic cross-sectional view illustrating an organic electroluminescent device according to an embodiment;

fig. 4 is a schematic cross-sectional view schematically showing an organic electroluminescent device according to an embodiment;

fig. 5 is a schematic cross-sectional view schematically showing an organic electroluminescent device according to an embodiment;

fig. 6 is a schematic cross-sectional view schematically showing an organic electroluminescent device according to an embodiment;

fig. 7 is a schematic cross-sectional view illustrating a display apparatus according to an embodiment; and

fig. 8 is a schematic cross-sectional view illustrating a display apparatus according to an embodiment.

Detailed Description

The present disclosure now will be described more fully hereinafter with reference to the accompanying drawings, in which embodiments are shown. The present disclosure may, however, be embodied in different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the disclosure to those skilled in the art.

In the drawings, the size, thickness, proportion, and dimension of elements may be exaggerated for convenience of description and for clarity. Like numbers refer to like elements throughout.

In the description, it will be understood that when an element (or region, layer, component, etc.) is referred to as being "on," "connected to" or "coupled to" another element, it can be directly on, connected or coupled to the other element or intervening elements may be present therebetween. In a similar sense, when an element (or region, layer, component, etc.) is described as "overlying" another element, it can directly overlie the other element or intervening elements may be present therebetween.

In the description, when an element is "directly on," "directly connected to" or "directly coupled to" another element, there are no intervening elements present. For example, "directly on.

As used herein, expressions for the singular, such as "a," "an," and "the," are intended to include the plural as well, unless the context clearly indicates otherwise.

As used herein, the term "and/or" includes any and all combinations of one or more of the associated listed items. For example, "a and/or B" may be understood to mean "A, B, or a and B". The terms "and" or "may be used in the sense of a conjunction or a conjunction, and may be understood to be equivalent to" and/or ".

For the purpose of its meaning and explanation, at least one of the terms "is intended to include the meaning of" at least one selected from. For example, "at least one of a and B" may be understood to mean "A, B, or a and B". When following a column of elements, at least one of the terms "modifies an entire column of elements without modifying individual elements of the column.

It will be understood that, although the terms first, second, etc. may be used herein to describe various elements, these elements should not be limited by these terms. These terms are only used to distinguish one element from another. Thus, a first element could be termed a second element without departing from the teachings of the present disclosure. Similarly, a second element may be termed a first element without departing from the scope of the present disclosure.

For convenience in description, spatially relative terms "below," "beneath," "lower," "above," "upper," and the like may be used herein to describe one element or component's relationship to another element or component as illustrated in the figures. It will be understood that the spatially relative terms are intended to encompass different orientations of the device in use or operation in addition to the orientation depicted in the figures. For example, in the case where the devices illustrated in the drawings are turned over, a device located "below" or "beneath" another device may be located "above" the other device. Thus, the exemplary term "below" may include both a lower position and an upper position. The device may also be oriented in other directions and the spatially relative terms may therefore be interpreted differently depending on the orientation.

The term "about" or "approximately" as used herein includes a stated value and means within an acceptable range of deviation of the stated value as determined by one of ordinary skill in the art taking into account the associated measurement and the error associated with the measurement of the quantity (i.e., the limitations of the measurement system). For example, "about" may mean within one or more standard deviations, or within ± 20%, ± 10%, or ± 5% of a stated value.

It will be understood that the terms "comprises," "comprising," "includes," "including," "contains," "containing," "has," "having," "has," "contains," "containing," and the like are intended to specify the presence of stated features, integers, steps, operations, elements, components, or groups thereof, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, or groups thereof in this disclosure.

Unless otherwise defined or implied herein, all terms (including technical and scientific terms) used have the same meaning as commonly understood by one of ordinary skill in the art to which this disclosure belongs. It will be further understood that terms, such as those defined in commonly used dictionaries, should be interpreted as having a meaning that is consistent with their meaning in the context of the relevant art and will not be interpreted in an idealized or overly formal sense unless expressly so defined herein.

Hereinafter, embodiments of the present disclosure will be explained with reference to the drawings.

Fig. 1 is a plan view illustrating an embodiment of a display device DD. Fig. 2 is a schematic cross-sectional view of a display device DD according to an embodiment. Fig. 2 is a schematic cross-sectional view showing a portion corresponding to the line I-I' in fig. 1.

The display device DD may include a display panel DP and an optical layer PP disposed on the display panel DP. The display panel DP may include organic electroluminescent devices ED-1, ED-2, and ED-3. The display device DD may include a plurality of each of the organic electroluminescent devices ED-1, ED-2, and ED-3. The optical layer PP may be disposed on the display panel DP and may control light reflected by external light at the display panel DP. The optical layer PP may include, for example, a polarizing layer or a color filter layer. Although not shown in the drawings, in an embodiment, the optical layer PP may be omitted from the display device DD.

The display panel DP may include a base layer BS, a circuit layer DP-CL provided on the base layer BS, and a display device layer DP-ED. The display device layer DP-ED may include a pixel defining layer PDL, organic electroluminescent devices ED-1, ED-2, and ED-3 disposed in the pixel defining layer PDL, and an encapsulation layer TFE disposed on the organic electroluminescent devices ED-1, ED-2, and ED-3.

The substrate layer BS may provide the surface of the substrate on which the display device layers DP-ED are disposed. The base layer BS may be a glass substrate, a metal substrate, a plastic substrate, or the like. However, the embodiment is not limited thereto, and the matrix layer BS may include an inorganic layer, an organic layer, or a composite material layer.

In an embodiment, the circuit layers DP-CL may be disposed on the base layer BS, and the circuit layers DP-CL may include a plurality of transistors (not shown). Each of the transistors (not shown) may include a control electrode, an input electrode, and an output electrode. For example, the circuit layer DP-CL may include switching transistors and driving transistors for driving the organic electroluminescent devices ED-1, ED-2, and ED-3 of the display device layer DP-ED.

Each of the organic electroluminescent devices ED-1, ED-2, and ED-3 may have a structure of an organic electroluminescent device ED according to an embodiment of fig. 3 to 6, which will be explained later. Each of the organic electroluminescent devices ED-1, ED-2, and ED-3 may include a first electrode EL1, a hole transport region HTR, emission layers EML-R, EML-G and EML-B, an electron transport region ETR, and a second electrode EL 2.

In fig. 2, an embodiment is shown in which emission layers EML-R, EML-G and EML-B of organic electroluminescent devices ED-1, ED-2, and ED-3 are disposed in an opening portion OH defined in a pixel defining layer PDL, and a hole transport region HTR, an electron transport region ETR, and a second electrode EL2 are each provided as a common layer in all of the organic electroluminescent devices ED-1, ED-2, and ED-3. However, the embodiments are not limited thereto. Although not shown in fig. 2, in an embodiment, the hole transport region HTR and the electron transport region ETR may be each patterned and provided in an opening portion OH defined in the pixel defining layer PDL. For example, in an embodiment, the hole transport regions HTR, the emission layers EML-R, EML-G and EML-B, and the electron transport regions ETR of the organic electroluminescent devices ED-1, ED-2, and ED-3 may each be patterned and provided by an inkjet printing method.

The encapsulation layer TFE may cover the organic electroluminescent devices ED-1, ED-2, and ED-3. The encapsulation layer TFE may encapsulate the display layer DP-ED. The encapsulation layer TFE may be a thin film encapsulation layer. The encapsulation layer TFE may be one layer or a stack of layers. The encapsulation layer TFE may include at least one insulating layer. The encapsulation layer TFE according to an embodiment may include at least one inorganic layer (hereinafter, encapsulation inorganic layer). The encapsulation layer TFE according to an embodiment may include at least one organic layer (hereinafter, encapsulation organic layer) and at least one encapsulation inorganic layer.

The encapsulation inorganic layer may protect the display device layer DP-ED from moisture and/or oxygen, and the encapsulation organic layer may protect the display device layer DP-ED from foreign substances such as dust particles. The encapsulation inorganic layer may include silicon nitride, silicon oxynitride, silicon oxide, titanium oxide, or aluminum oxide, without being particularly limited. The encapsulation organic layer may include an acrylic compound, an epoxy-based compound, or the like. The encapsulation organic layer may include a photopolymerizable organic material without particular limitation.

The encapsulation layer TFE may be disposed on the second electrode EL2 and may be disposed to fill the opening portion OH.

Referring to fig. 1 and 2, the display device DD may include a non-light emitting area NPXA and light emitting areas PXA-R, PXA-G and PXA-B. The light emitting regions PXA-R, PXA-G and PXA-B may be regions that emit light generated by the organic electroluminescent devices ED-1, ED-2, and ED-3, respectively. The light emitting areas PXA-R, PXA-G and PXA-B may be separated from each other on a plane.

The light emitting regions PXA-R, PXA-G and PXA-B may be regions separated by the pixel defining layer PDL. The non-light emitting region NPXA may be an area between adjacent light emitting regions PXA-R, PXA-G and PXA-B and may be an area corresponding to the pixel defining layer PDL. Each of the light emitting regions PXA-R, PXA-G and PXA-B may correspond to a pixel. The pixel defining layer PDL may separate the organic electroluminescent devices ED-1, ED-2, and ED-3. The emission layers EML-R, EML-G and EML-B of the organic electroluminescent devices ED-1, ED-2, and ED-3 may be disposed in the opening portions OH defined in the pixel defining layer PDL and separated from each other.

The light emitting regions PXA-R, PXA-G and PXA-B may be divided into a plurality of groups according to the color of light generated by each of the organic electroluminescent devices ED-1, ED-2, and ED-3. In the display device DD of the embodiment shown in fig. 1 and 2, three light emitting regions PXA-R, PXA-G and PXA-B emitting red light, green light, and blue light, respectively, are illustrated as an embodiment. For example, the display device DD of the embodiment may include red light emitting areas PXA-R, green light emitting areas PXA-G, and blue light emitting areas PXA-B separated from each other.

In the display device DD according to the embodiment, the organic electroluminescent devices ED-1, ED-2, and ED-3 may each emit light having a different wavelength region. For example, in an embodiment, the display device DD may include a first organic electroluminescent device ED-1 emitting red light, a second organic electroluminescent device ED-2 emitting green light, and a third organic electroluminescent device ED-3 emitting blue light. For example, each of the red light emitting region PXA-R, the green light emitting region PXA-G, and the blue light emitting region PXA-B of the display device DD may correspond to the first organic electroluminescent device ED-1, the second organic electroluminescent device ED-2, and the third organic electroluminescent device ED-3, respectively.

However, the embodiment is not limited thereto, and the first to third organic electroluminescent devices ED-1, ED-2 and ED-3 may emit light in the same wavelength region, or at least one thereof may emit light in different wavelength regions. For example, the first to third organic electroluminescent devices ED-1, ED-2 and ED-3 may each emit blue light.

The light emitting regions PXA-R, PXA-G and PXA-B in the display device DD according to the embodiment may be arranged in a stripe shape. Referring to fig. 1, a plurality of red light-emitting areas PXA-R, a plurality of green light-emitting areas PXA-G, and a plurality of blue light-emitting areas PXA-B may be arranged along the second direction DR 2. The red light-emitting areas PXA-R, the green light-emitting areas PXA-G, and the blue light-emitting areas PXA-B may be alternately arranged in the first direction DR 1.

In fig. 1 and 2, areas of the light emitting areas PXA-R, PXA-G and PXA-B are shown to be similar, but the embodiment is not limited thereto. The areas of the light emitting areas PXA-R, PXA-G and PXA-B may be different from each other according to the wavelength region of the emitted light. The areas of the light emitting regions PXA-R, PXA-G and PXA-B may be areas in a plan view defined by the first direction DR1 and the second direction DR 2.

The arrangement type of the light emitting regions PXA-R, PXA-G and PXA-B is not limited to the configuration shown in fig. 1, and the arrangement order of the red light emitting region PXA-R, the green light emitting region PXA-G, and the blue light emitting region PXA-B may be provided in various combinations according to the nature of display quality required for the display device DD. For example, the arrangement type of the light emitting areas PXA-R, PXA-G and PXA-B may be

An arrangement type or a diamond arrangement type.

In an embodiment, the areas of light emitting areas PXA-R, PXA-G and PXA-B may be different from each other. For example, in an embodiment, the area of the green light emitting region PXA-G may be smaller than the area of the blue light emitting region PXA-B, but the embodiment is not limited thereto.

Hereinafter, fig. 3 to 6 are each a schematic cross-sectional view illustrating an organic electroluminescent device according to an embodiment. As shown in fig. 3, the organic electroluminescent device ED according to the embodiment may include a first electrode EL1, a hole transport region HTR, an emission layer EML, an electron transport region ETR, and a second electrode EL2, which are sequentially stacked.

The organic electroluminescent device ED of the embodiment may include a polycyclic compound of an embodiment to be explained later in an emission layer EML disposed between the first electrode EL1 and the second electrode EL 2. However, the embodiment is not limited thereto, and the organic electroluminescent device ED of the embodiment may include a polycyclic compound of an embodiment to be explained later in a hole transport region HTR or an electron transport region ETR in a functional layer disposed between the first electrode EL1 and the second electrode EL2, or may include a polycyclic compound according to an embodiment to be explained later in a capping layer CPL disposed on the second electrode EL2, in addition to the emission layer EML.

In comparison with fig. 3, fig. 4 shows a schematic cross-sectional view of an organic electroluminescent device ED of an embodiment in which a hole transport region HTR includes a hole injection layer HIL and a hole transport layer HTL, and an electron transport region ETR includes an electron injection layer EIL and an electron transport layer ETL. In comparison with fig. 3, fig. 5 shows a schematic cross-sectional view of the organic electroluminescent device ED of the embodiment, in which the hole transport region HTR includes a hole injection layer HIL, a hole transport layer HTL, and an electron blocking layer EBL, and the electron transport region ETR includes an electron injection layer EIL, an electron transport layer ETL, and a hole blocking layer HBL. In comparison with fig. 4, fig. 6 shows a schematic cross-sectional view of an organic electroluminescent device ED of an embodiment, which includes a capping layer CPL disposed on a second electrode EL 2.

The first electrode EL1 has conductivity. The first electrode EL1 may be formed using a metal alloy or a conductive compound. The first electrode EL1 may be an anode or a cathode. However, the embodiments are not limited thereto. In an embodiment, the first electrode EL1 may be a pixel electrode. The first electrode EL1 may be a transmissive electrode, a transflective electrode, or a reflective electrode. If the first electrode EL1 is a transmissive electrode, the first electrode EL1 may include a transparent metal oxide, such as Indium Tin Oxide (ITO), Indium Zinc Oxide (IZO), zinc oxide (ZnO), and Indium Tin Zinc Oxide (ITZO). If the first electrode EL1 is a transflective or reflective electrode, the first electrode EL1 can comprise Ag, Mg, Cu, Al, Pt, Pd, Au, Ni, Nd, Ir, Cr, Li, Ca, LiF, Mo, Ti, compounds thereof, or mixtures thereof (e.g., mixtures of Ag and Mg). In an embodiment, the first electrode EL1 may have a structure of a plurality of layers including a reflective layer or a semi-reflective layer formed using the above materials, and a transmissive conductive layer formed using ITO, IZO, ZnO, or ITZO. For example, the first electrode EL1 may have a three-layer structure of ITO/Ag/ITO. However, the embodiments are not limited thereto. The thickness of the first electrode EL1 may be about

To about

For example, the thickness of the first electrode EL1 may be about

To about

A hole transport region HTR is provided on the first electrode EL 1. The hole transport region HTR may include a hole injection layer HIL, a hole transport layer HTL, a hole buffer layer (not shown), and an electron blocking layer EBLAt least one of (a). The thickness of the hole transport region HTR can be, for example, about

To about

The hole transport region HTR may have a layer formed using a single material, a layer formed using different materials, or a multilayer structure including layers formed using different materials.

For example, the hole transport region HTR may have a structure of a single layer of the hole injection layer HIL or the hole transport layer HTL, or may have a structure of a single layer formed using a hole injection material and a hole transport material. In embodiments, the hole transport region HTR may have a structure of a single layer formed using a plurality of different materials, or a structure of a hole injection layer HIL/hole transport layer HTL, a hole injection layer HIL/hole transport layer HTL/hole buffer layer (not shown), a hole injection layer HIL/hole buffer layer (not shown), a hole transport layer HTL/hole buffer layer (not shown), or a hole injection layer HIL/hole transport layer HTL/electron blocking layer EBL stacked from the first electrode EL1, without limitation.

The hole transport region HTR may be formed using various methods such as a vacuum deposition method, a spin coating method, a casting method, a Langmuir-Blodgett (LB) method, an inkjet printing method, a laser printing method, and a Laser Induced Thermal Imaging (LITI) method.

The hole transport region HTR may include a compound represented by the following formula H-1.

[ formula H-1]

In the above formula H-1, L _a1 And L _a2 May each independently be a direct bond, a substituted or unsubstituted arylene group having 6 to 30 ring-forming carbon atoms, or a substituted or unsubstituted heteroarylene group having 2 to 30 ring-forming carbon atomsAn aryl group. In the formula H-1, a-1 and b-1 may each independently be an integer of 0 to 10. In the formula H-1, if a-1 or b-1 is 2 or greater than 2, a plurality of L _a1 A group and a plurality of L _a2 Each group may independently be a substituted or unsubstituted arylene group having 6 to 30 ring-forming carbon atoms or a substituted or unsubstituted heteroarylene group having 2 to 30 ring-forming carbon atoms.

In the formula H-1, Ar _a1 To Ar _a3 May each independently be a substituted or unsubstituted aryl group having 6 to 30 ring-forming carbon atoms or a substituted or unsubstituted heteroaryl group having 2 to 30 ring-forming carbon atoms.

The compound represented by the formula H-1 may be a monoamine compound. In another embodiment, the compound represented by the formula H-1 may be a diamine compound, wherein Ar is _a1 To Ar _a3 Contains an amine group as a substituent. The compound represented by the formula H-1 may be wherein Ar _a1 To Ar _a3 At least one of the carbazole-based compounds including a substituted or unsubstituted carbazole group or wherein Ar _a1 To Ar _a3 At least one of the fluorene-based compounds includes a substituted or unsubstituted fluorene group.

The compound represented by the formula H-1 may be any one selected from the following compound group H. However, the compounds shown in compound group H are only examples, and the compounds represented by formula H-1 are not limited to those listed in compound group H below.

[ Compound group H ]

The hole transport region HTR may comprise a phthalocyanine compound (e.g., copper phthalocyanine), N ¹ ,N ¹ '- ([1,1' -Biphenyl)]-4,4' -diyl) bis (N) ¹ -phenyl-N ⁴ ,N ⁴ Di-m-tolylbenzene-1, 4-diamine) (DNTPD), 4' - [ tris (3-methylphenyl) phenylamino]Triphenylamine (m-MTDATA), 4 '-tris (N, N-diphenylamino) triphenylamine (TDATA), 4' -tris [ N- (1-naphthyl) -N-phenylamino-]-triphenylamine (1-TNATA), 4' -tris [ N- (2-naphthyl) -N-phenylamino]-triphenylamine (2-TNATA), poly (3, 4-ethylenedioxythiophene)/poly (4-styrenesulfonate) (PEDOT/PSS), polyaniline/dodecylbenzenesulfonic acid (PANI/DBSA), polyaniline/camphorsulfonic acid (PANI/CSA), polyaniline/poly (4-styrenesulfonate) (PANI/PSS), N ' -bis (naphthalen-1-yl) -N, N ' -diphenyl-benzidine (NPB), triphenylamine-containing polyetherketone (TPAPEK), 4-isopropyl-4 ' -methyldiphenyliodonium [ tetrakis (pentafluorophenyl) borate]And dipyrazino [2,3-f:2',3' -h]Quinoxaline-2, 3,6,7,10, 11-hexacyanonitrile (HAT-CN).

The hole transport region HTR may contain, for example, carbazole derivatives (e.g., N-phenylcarbazole and polyvinylcarbazole), fluorene-based derivatives, N '-bis (3-methylphenyl) -N, N' -diphenyl- [1,1 '-biphenyl ] -4,4' -diamine (TPD), triphenylamine-based derivatives (e.g., 4',4 ″ -tris (N-carbazolyl) triphenylamine (TCTA)), N' -bis (naphthalen-1-yl) -N, N '-diphenyl-benzidine (NPB), 4' -cyclohexylidenebis [ N, N-bis (4-methylphenyl) aniline ] (TAPC), 4 '-bis [ N, N' - (3-tolyl) amino ] -3,3' -dimethylbiphenyl (HMTPD), 1, 3-bis (N-carbazolyl) benzene (mCP), and the like.

The hole transport region HTR may include 9- (4-tert-butylphenyl) -3, 6-bis (triphenylsilyl) -9H-carbazole (CzSi), 9-phenyl-9H-3, 9' -bicarbazole (CCP), 1, 3-bis (1, 8-dimethyl-9H-carbazol-9-yl) benzene (mdp), and the like.

The hole transport region HTR may include a compound of a hole transport region in at least one of the hole injection layer HIL, the hole transport layer HTL, and the electron blocking layer EBL.

The thickness of the hole transport region HTR may be about

To about

For example, the thickness of the hole transport region HTR can beAbout

To about

The thickness of the hole injection layer HIL may be, for example, about

To about

The thickness of the hole transport layer HTL may be about

To about

For example, the thickness of the electron blocking layer EBL may be about

To about

If the thicknesses of the hole transport region HTR, the hole injection layer HIL, the hole transport layer HTL, and the electron blocking layer EBL satisfy the above-described ranges, satisfactory hole transport properties can be achieved without a significant increase in driving voltage.

In addition to the above-described materials, the hole transport region HTR may further include a charge generation material to increase conductivity. The charge generation material may be uniformly or non-uniformly dispersed in the hole transport region HTR. The charge generating material may be, for example, a p-dopant. The p-dopant may include at least one of a quinone derivative, a metal oxide, and a cyano group-containing compound, without limitation. For example, non-limiting examples of the p-dopant may include quinone derivatives such as Tetracyanoquinodimethane (TCNQ) and 2,3,5, 6-tetrafluoro-7, 7',8,8' -tetracyanoquinodimethane (F4-TCNQ), metal oxides such as tungsten oxide and molybdenum oxide, and the like. However, the embodiments are not limited thereto.

As described above, the hole transport region HTR may further include at least one of a hole buffer layer (not shown) and an electron blocking layer EBL in addition to the hole injection layer HIL and the hole transport layer HTL. The hole buffer layer (not shown) may compensate a resonance distance according to a wavelength of light emitted from the emission layer EML, and may increase light emission efficiency. As a material contained in the hole buffer layer (not shown), a material that can be contained in the hole transport region HTR can be used. The electron blocking layer EBL may block electron injection from the electron transport region ETR to the hole transport region HTR.

The emission layer EML is provided on the hole transport region HTR. The emission layer EML may have, for example, about

To about

Of (c) is used. For example, the emissive layer EML may have an approximate thickness

To about

Is measured. The emission layer EML may have a layer formed using a single material, a layer formed using different materials, or a multi-layer structure having layers formed using different materials.

In the specification, the term "substituted or unsubstituted" as used herein may mean a group substituted or unsubstituted with at least one substituent selected from the group consisting of a deuterium atom, a halogen atom, a cyano group, a nitro group, an amino group, a silyl group, an oxy group, a thio group, a sulfinyl group, a sulfonyl group, a carbonyl group, a boron group, a phosphine oxide group, a phosphine sulfide group, an alkyl group, an alkenyl group, an alkoxy group, an aliphatic hydrocarbon ring group, an aryl group, and a heterocyclic group. Each of the substituents listed above may itself be substituted or unsubstituted. For example, a biphenyl group may be interpreted as an aryl group or as a phenyl group substituted with a phenyl group.

In the specification, the term "combine with an adjacent group to form a ring" may mean a group that combines with an adjacent group to form a substituted or unsubstituted hydrocarbon ring or a substituted or unsubstituted heterocyclic ring. The hydrocarbon ring may include an aliphatic hydrocarbon ring and an aromatic hydrocarbon ring. The heterocyclic ring may include an aliphatic heterocyclic ring and an aromatic heterocyclic ring. The hydrocarbon ring and the heterocyclic ring may each be monocyclic or polycyclic. A ring formed by groups bound to each other may be bound to another ring to form a spiro structure.

In the specification, the term "adjacent group" may mean a substituent that substitutes for an atom directly bonded to an atom substituted with a corresponding substituent, another substituent that substitutes for an atom substituted with a corresponding substituent, or a substituent that is sterically positioned at the closest position to a corresponding substituent. For example, two methyl groups in 1, 2-dimethylbenzene can be interpreted as "vicinal groups" to each other, and two ethyl groups in 1, 1-diethylcyclopentane can be interpreted as "vicinal groups" to each other. For example, two methyl groups in 4, 5-dimethylphenanthrene can be interpreted as "adjacent groups" to each other.

In the specification, examples of the halogen atom may include a fluorine atom, a chlorine atom, a bromine atom and an iodine atom.

In the specification, the alkyl group may be of a straight chain, branched chain or cyclic type. The number of carbon atoms in the alkyl group may be 1 to 50, 1 to 30, 1 to 20, 1 to 10, or 1 to 6. Examples of the alkyl group may include a methyl group, an ethyl group, a n-propyl group, an isopropyl group, a n-butyl group, a sec-butyl group, a tert-butyl group, an isobutyl group, a 2-ethylbutyl group, a3, 3-dimethylbutyl group, a n-pentyl group, an isopentyl group, a neopentyl group, a tert-pentyl group, a cyclopentyl group, a 1-methylpentyl group, a 3-methylpentyl group, a 2-ethylpentyl group, a 4-methyl-2-pentyl group, a n-hexyl group, a 1-methylhexyl group, a 2-ethylhexyl group, a 2-butylhexyl group, a cyclohexyl group, a 4-methylcyclohexyl group, a 4-tert-butylcyclohexyl group, a n-heptyl group, a 1-methylheptyl group, a2, 2-dimethylheptyl group, a, 2-ethylheptyl group, 2-butylheptyl group, n-octyl group, tert-octyl group, 2-ethyloctyl group, 2-butyloctyl group, 2-hexyloctyl group, 3, 7-dimethyloctyl group, cyclooctyl group, n-nonyl group, n-decyl group, adamantyl group, 2-ethyldecyl group, 2-butyldecyl group, 2-hexyldecyl group, 2-octyldecyl group, n-undecyl group, n-dodecyl group, 2-ethyldodecyl group, 2-butyldodecyl group, 2-hexyldodecyl group, 2-octyldodecyl group, n-tridecyl group, n-tetradecyl group, n-pentadecyl group, n-hexadecyl group, 2-ethylhexadecyl group, n-ethylhexadecyl group, 2-butylhexadecyl group, 2-hexylhexadecyl group, 2-octylhexadecyl group, n-heptadecyl group, n-octadecyl group, n-nonadecyl group, n-eicosyl group, 2-ethyleicosyl group, 2-butyleicosyl group, 2-hexyleicosyl group, 2-octyleicosyl group, n-heneicosyl group, n-docosyl group, n-tricosyl group, n-tetracosyl group, n-pentacosyl group, n-hexacosyl group, n-heptacosyl group, n-octacosyl group, n-nonacosyl group, n-triacontyl group and the like, but are not limited thereto.

In the specification, the hydrocarbon ring group may be any functional group or substituent derived from an aliphatic hydrocarbon ring, or any functional group or substituent derived from an aromatic hydrocarbon ring. The number of ring-forming carbon atoms in the hydrocarbon ring group may be 5 to 60, 5 to 30, or 5 to 20.

In the specification, the aryl group may be any functional group or substituent derived from an aromatic hydrocarbon ring. The aryl group can be a monocyclic aryl group or a polycyclic aryl group. The number of ring-forming carbon atoms in the aryl group may be 6 to 30, 6 to 20, or 6 to 15. Examples of the aryl group may include a phenyl group, a naphthyl group, a fluorenyl group, an anthracyl group, a phenanthryl group, a biphenyl group, a terphenyl group, a quaterphenyl group, a pentabiphenyl group, a hexabiphenyl group, a benzophenanthryl group, a pyrenyl groupA group, a benzofluoranthryl group,

A radical group, etc., but the embodiment is not limited thereto.

In the specification, a fluorenyl group may be substituted, and two substituents may be combined with each other to form a spiro structure. Examples of substituted fluorenyl groups are as follows. However, the embodiments are not limited thereto.

In the specification, the heterocyclic group may be any functional group or substituent derived from a ring containing at least one of B, O, N, P, Si and S as a heteroatom. The heterocyclic group may be an aliphatic heterocyclic group or an aromatic heterocyclic group. The aromatic heterocyclic group may be a heteroaryl group. The aliphatic heterocyclic group and the aromatic heterocyclic group may each be monocyclic or polycyclic.

In the specification, the heterocyclic group may contain at least one of B, O, N, P, Si and S as a heteroatom. If the heterocyclic group contains two or more heteroatoms, the two or more heteroatoms may be the same as or different from each other. The heterocyclic group may be a monocyclic heterocyclic group or a polycyclic heterocyclic group, and the heterocyclic group may be a heteroaryl group. The number of ring-forming carbon atoms in the heterocyclic group may be 2 to 30, 2 to 20, or 2 to 10.

In the specification, the aliphatic heterocyclic group may contain at least one of B, O, N, P, Si and S as a heteroatom. The number of ring-forming carbon atoms in the aliphatic heterocyclic group may be 2 to 30, 2 to 20 or 2 to 10. Examples of the aliphatic heterocyclic group may include an oxetanyl group, a thietanyl group, a pyrrolidine group, a piperidine group, a tetrahydrofuran group, a tetrahydrothiophene group, a thietanyl group, a tetrahydropyran group, a1, 4-dioxane group, and the like, but the embodiment is not limited thereto.

In the specification, the heteroaryl group may contain at least one of B, O, N, P, Si and S as a heteroatom. When the heteroaryl group contains two or more heteroatoms, the two or more heteroatoms may be the same as or different from each other. The heteroaryl group can be a monocyclic heteroaryl group or a polycyclic heteroaryl group. The number of ring-forming carbon atoms in the heteroaryl group may be 2 to 30, 2 to 20, or 2 to 10. Examples of heteroaryl groups may include groups derived from: thiophene group, furan group, pyrrole group, imidazole group, triazole group, pyridine group, bipyridine group, pyrimidine group, triazine group, acridine group, pyridazine group, pyrazine group, quinoline group, quinazoline group, quinoxaline group, phenoxazine group, phthalazine group, pyridopyrimidine group, pyridopyrazine group, pyrazinopyrazine group, isoquinoline group, indole group, carbazole group, N-arylcarbazole group, N-heteroarylcarbazole group, N-alkylcarbazole group, benzoxazole group, benzimidazole group, benzothiazole group, benzocarbazole group, benzothiophene group, dibenzothiophene group, thienothiophene group, benzofuran group, phenanthroline group, thiazole group, isoxazole group, oxazole group, oxadiazole group, thiadiazole group, phenothiazine group, pyridine group, pyrimidine group, triazine group, acridine group, pyridazine group, pyrazine group, quinoline group, quinoxaline group, benzimidazole group, thiadiazole group, benzothiazole group, phenanthroline group, and the like, Dibenzosilole groups, dibenzofuran groups, and the like, but embodiments are not limited thereto.

In the specification, the above description about the aryl group may be applied to the arylene group, but the arylene group is a divalent group.

In the specification, the above description about the heteroaryl group may be applied to the heteroarylene group, but the heteroarylene group is a divalent group.

In the specification, the silyl group includes an alkylsilyl group and an arylsilyl group. Examples of the silyl group may include trimethylsilyl, triethylsilyl, t-butyldimethylsilyl, vinyldimethylsilyl, propyldimethylsilyl, triphenylsilyl, diphenylsilyl, phenylsilyl, and the like. However, embodiments of the inventive concept are not limited thereto.

In the specification, the number of carbon atoms in the amino group is not particularly limited, but may be 1 to 30. The amino group can include an alkylamino group, an arylamino group, or a heteroarylamino group. Examples of the amino group include, but are not limited to, a methylamino group, a dimethylamino group, a phenylamino group, a diphenylamino group, a naphthylamino group, a 9-methyl-anthrylamino group, and the like.

The thio group herein may include alkylthio groups and arylthio groups. A thio group may mean that the sulfur atom is bonded to an alkyl group or an aryl group as defined above. Examples of the thio group may include a methylthio group, an ethylthio group, a propylthio group, a pentylthio group, a hexylthio group, an octylthio group, a dodecylthio group, a cyclopentylthio group, a cyclohexylthio group, a phenylthio group, a naphthylthio group, but the embodiments of the inventive concept are not limited thereto.

In the description, the oxy group may include an alkoxy group and an aryloxy group. For example, in an oxy group, an alkyl group or an aryl group as defined above may be bonded to an oxygen atom. Examples of the oxy group may include methoxy, ethoxy, n-propoxy, isopropoxy, butoxy, pentyloxy, hexyloxy, octyloxy, nonyloxy, decyloxy, benzyloxy and the like. However, one or more embodiments of the present disclosure are not limited thereto.

In the description, the boron group includes an alkyl boron group and an aryl boron group. For example, in a boron group, an alkyl group or an aryl group as defined above may be bonded to the boron atom. Examples of the boron group include a trimethylboron group, a triethylboron group, a t-butyldimethylboron group, a triphenylboron group, a diphenylboron group, a phenylboron group, and the like, without limitation.

In the specification, an alkenyl group may be a hydrocarbon group containing at least one carbon double bond at the middle or end of an alkyl group having 2 or more than 2 carbon atoms. The alkenyl group may be straight or branched. The number of carbon atoms is not particularly limited, but may be 2 to 30, 2 to 20, or 2 to 10. Examples of the alkenyl group may include a vinyl group, a 1-butenyl group, a 1-pentenyl group, a1, 3-butadienylaryl group, a styryl group, a styrylvinyl group, and the like, without limitation.

In the specification, an alkynyl group may be a hydrocarbon group containing at least one carbon triple bond at the middle or end of an alkyl group having 2 or more than 2 carbon atoms. Alkynyl groups may be straight or branched. The number of carbon atoms is not particularly limited, but may be 2 to 30, 2 to 20, or 2 to 10. Examples of the alkynyl group may include an ethynyl group, a propynyl group, and the like, without limitation.

A direct bond may herein mean a single bond.

In the specification, "-" as used herein denotes a binding site to an adjacent atom.

The organic electroluminescent device ED of the embodiment may include a polycyclic compound according to the embodiment. The polycyclic compound of the embodiment may be represented by formula 1 below.

[ formula 1]

In formula 1, X ₁ And X ₂ May each independently be O, S or N (R) ₇ ) And R is ₇ May be a hydrogen atom, a deuterium atom, a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted aryl group having 6 to 30 ring-forming carbon atoms, or a substituted or unsubstituted heteroaryl group having 2 to 30 ring-forming carbon atoms, or may be bonded to an adjacent group to form a ring.

In formula 1, R ₁ To R ₄ 、R _5-1 To R _5-3 And R _6-1 To R _6-3 May each independently be a hydrogen atom, a deuterium atom, a halogen atom, a nitro group, a cyano group, a hydroxyl group, a substituted or unsubstituted amine group, a substituted or unsubstituted thiol group, a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted aryl group having 6 to 30 ring-forming carbon atomsA group, or a substituted or unsubstituted heteroaryl group having 2 to 30 ring-forming carbon atoms, or may be combined with an adjacent group to form a ring.

In formula 1, e and f may each independently be an integer of 0 to 4. If e is 2 or greater than 2, a plurality of R ₁ The radicals may be identical or different and, if f is 2 or greater than 2, a plurality of R ₂ The groups may be the same or different.

In formula 1, g may be an integer of 0 to 2. If g is 2, a plurality of R ₃ The groups may be the same or different.

In formula 1, h may be an integer of 0 to 3. If h is 2 or greater than 2, a plurality of R ₄ The groups may be the same or different.

In formula 1, Y ₁ And Y ₂ May each independently be a hydrogen atom, a deuterium atom, a substituted or unsubstituted alkyl group having 6 to 20 carbon atoms, a substituted or unsubstituted aryl group having 6 to 30 ring-forming carbon atoms, or a substituted or unsubstituted heteroaryl group having 2 to 30 ring-forming carbon atoms, and Y ₁ And Y ₂ At least one of which may be a substituted or unsubstituted alkyl group having 6 to 20 carbon atoms, a substituted or unsubstituted aryl group having 6 to 30 ring-forming carbon atoms, or a substituted or unsubstituted heteroaryl group having 2 to 30 ring-forming carbon atoms.

In embodiments, X in formula 1 ₁ And X ₂ May be N (R) ₇ ) And R is ₇ May be a substituted or unsubstituted aryl group having 6 to 30 ring-forming carbon atoms or a substituted or unsubstituted heteroaryl group having 2 to 30 ring-forming carbon atoms. For example, the polycyclic compound represented by formula 1 may be represented by any one of the following formulas 2-1 to 2-5.

[ formula 2-1]

[ formula 2-2]

[ formulas 2 to 3]

[ formulae 2 to 4]

[ formulas 2 to 5]

In formulae 2-1 to 2-5, Ar _1-1 And Ar _1-2 May each independently be a substituted or unsubstituted aryl group having 6 to 30 ring-forming carbon atoms or a substituted or unsubstituted heteroaryl group having 2 to 30 ring-forming carbon atoms.

In the formulae 2-1 to 2-5, R ₁ To R ₄ 、R _5-1 To R _5-3 、R _6-1 To R _6-3 、Y ₁ 、Y ₂ And e to h may be the same as defined with respect to formula 1.

In the formulae 5-1 to 5-3, R _a1 To R _a5 May each independently be a hydrogen atom, a deuterium atom, a halogen atom, a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted aryl group having 6 to 30 ring-forming carbon atoms, or a substituted or unsubstituted aryl group having 2 to 30 ring-forming carbon atomsA heteroaryl group of carbon atoms.

In formula 5-1, m1 may be an integer of 0 to 5. If m1 is 2 or greater than 2, a plurality of R _a1 The groups may be the same or different.

In formula 5-2, m2 may be an integer of 0 to 9. If m2 is 2 or greater than 2, a plurality of R _a2 The groups may be the same or different.

In formula 5-3, m3 may be an integer of 0 to 5. If m3 is 2 or greater than 2, a plurality of R _a3 The groups may be the same or different.

In formula 5-3, m4 may be an integer of 0 to 3. If m4 is 2 or greater than 2, a plurality of R _a4 The groups may be the same or different.

In formula 5-3, m5 may be an integer of 0 to 5. If m5 is 2 or greater than 2, a plurality of R _a5 The groups may be the same or different.

In embodiments, R of formula 1 _5-1 To R _5-3 And R _6-1 To R _6-3 May be a substituted amine group.

In embodiments, R of formula 1 _5-2 May be a substituted amine group. For example, the polycyclic compound represented by formula 1 may be represented by formula 3-1 below.

[ formula 3-1]

In formula 3-1, Ar _3-1 And Ar _3-2 May each independently be a substituted or unsubstituted aryl group having 6 to 30 ring-forming carbon atoms, and X ₁ 、X ₂ 、R ₁ To R ₄ 、R _5-1 、R _5-3 、R _6-1 To R _6-3 、Y ₁ 、Y ₂ And e to h may be the same as defined with respect to formula 1.

In embodiments, R of formula 1 _6-2 May be a substituted amine group. For example, the polycyclic compound represented by formula 1 may be represented by the following formula 3-2.

[ formula 3-2]

In formula 3-2, Ar _4-1 And Ar _4-2 May each independently be a substituted or unsubstituted aryl group having 6 to 30 ring-forming carbon atoms, and X ₁ 、X ₂ 、R ₁ To R ₄ 、R _5-1 To R _5-3 、R _6-1 、R _6-3 、Y ₁ 、Y ₂ And e to h may be the same as defined with respect to formula 1.

In embodiments, R of formula 1 _5-2 And R _6-2 May each be a substituted amine group. For example, the polycyclic compound represented by formula 1 may be represented by formula 4 below.

[ formula 4]

In embodiments, in formula 3-1 or formula 4, Ar _3-1 And Ar _3-2 May each independently be a substituted or unsubstituted aryl group having from 6 to 18 ring-forming carbon atoms.

In embodiments, in formula 3-2 or formula 4, Ar _4-1 And Ar _4-2 May each independently be a substituted or unsubstituted aryl group having from 6 to 18 ring-forming carbon atoms.

The polycyclic compound represented by formula 1 according to the embodiment may be any one selected from the following compound group 1. However, the embodiments are not limited thereto.

[ Compound group 1]

The polycyclic compound of the embodiment represented by formula 1 may be used as a fluorescent material or as a Thermally Activated Delayed Fluorescence (TADF) material. For example, the polycyclic compound of the embodiment may be used as a fluorescent dopant material emitting blue light or a TADF dopant material. The polycyclic compound of the embodiment may have a center wavelength (λ) in a wavelength region equal to or less than about 490nm _max ) The light-emitting material of (1). For example, the polycyclic compound of the embodiment represented by formula 1 may be a light emitting material having a central wavelength in a wavelength region of about 430nm to about 480 nm. For example, the polycyclic compound of an embodiment may be a blue thermally activated delayed fluorescence dopant. For example, in an embodiment, the emission layer EML may be a thermally activated delayed fluorescent layer emitting light having a wavelength of about 430nm to about 480 nm. However, the embodiments are not limited thereto.

In the organic electroluminescent device ED of the embodiments shown in fig. 3 to 6, the emission layer EML may include a first compound and a second compound. For example, the first compound may include a dopant and the second compound may include a host. In an embodiment, the emission layer EML may be a delayed fluorescence emission layer including a first compound and a second compound, and the first compound may be a polycyclic compound represented by formula 1.

The polycyclic compound according to the embodiment may increase k according to an increase in spin orbit interaction by a heavy atom effect due to introduction of a sulfur atom _RISC And triplet-triplet annihilation (TTA) and singlet-triplet annihilation (STA) can be suppressed. Since the polycyclic compound of the embodiment represented by formula 1 includes a substituent Y at a specific position ₁ And/or Y ₂ The molecular volume may increase and, therefore, the distance between adjacent molecules in the excited state may increase, thereby limiting TTA and STA. Accordingly, the organic electroluminescent device ED of the embodiment including the polycyclic compound of the embodiment in the emission layer EML may limit roll-off and show improved lifetime characteristics.

The organic electroluminescent device ED of the embodiment including the polycyclic compound of the embodiment represented by formula 1 in the emission layer EML may emit delayed fluorescence. The organic electroluminescent device ED of the embodiment may emit Thermally Activated Delayed Fluorescence (TADF), and the organic electroluminescent device ED may exhibit high efficiency properties.

The organic electroluminescent device ED of the embodiment may further include the following materials for an emission layer in addition to the polycyclic compound of the embodiment. In the organic electroluminescent device ED of the embodiment, the emission layer EML may include anthracene derivatives, pyrene derivatives, fluoranthene derivatives, anthracene derivatives, and the like,

A derivative, a dihydrobenzanthracene derivative, or a triphenylene derivative. For example, the emission layer EML may include an anthracene derivative or a pyrene derivative.

In the organic electroluminescent device ED shown in fig. 3 to 6, the emission layer EML may include a host and a dopant, and the emission layer EML may include a compound represented by the following formula E-1. A compound represented by the following formula E-1 can be used as a fluorescent host material.

[ formula E-1]

In the formula E-1, R ₃₁ To R ₄₀ May each independently be a hydrogen atom, a deuterium atom, a halogen atom, a substituted or unsubstituted silyl group, a substituted or unsubstituted alkyl group having 1 to 10 carbon atoms, a substituted or unsubstituted aryl group having 6 to 30 ring-forming carbon atoms, or a substituted or unsubstituted heteroaryl group having 2 to 30 ring-forming carbon atoms, or may be bonded to an adjacent group to form a ring. In the formula E-1, R ₃₁ To R ₄₀ May combine with adjacent groups to form a saturated hydrocarbon ring or an unsaturated hydrocarbon ring.

In formula E-1, c and d may each independently be an integer of 0 to 5.

The compound represented by formula E-1 may be any one selected from the following compounds E1 to E19.

In embodiments, the emissive layer EML may comprise a compound represented by formula E-2a or formula E-2b below. The compound represented by the following formula E-2a or formula E-2b may be used as a phosphorescent host material.

[ formula E-2a ]

In formula E-2a, a can be an integer from 0 to 10, and L _a May be a direct bond, a substituted or unsubstituted arylene group having 6 to 30 ring-forming carbon atoms, or a substituted or unsubstituted heteroarylene group having 2 to 30 ring-forming carbon atoms. If a is 2 or greater than 2, a plurality of L _a Each group may independently be a substituted or unsubstituted arylene group having 6 to 30 ring-forming carbon atoms or a substituted or unsubstituted heteroarylene group having 2 to 30 ring-forming carbon atoms.

In the formula E-2a, A ₁ To A ₅ May each independently be N or c (ri). R _a To R _i May each independently be a hydrogen atom, a deuterium atom, a substituted or unsubstituted amine group, a substituted or unsubstituted thio group, a substituted or unsubstituted oxy group, a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted alkenyl group having 2 to 20 carbon atoms, a substituted or unsubstituted aryl group having 6 to 30 ring-forming carbon atoms, or a substituted or unsubstituted heteroaryl group having 2 to 30 ring-forming carbon atoms, or may be combined with an adjacent group to form a ring. R _a To R _i May combine with adjacent groups to form a hydrocarbon ring or comprise N, O,S, etc. as a heterocyclic ring of a ring-constituting atom.

In the formula E-2a, A ₁ To A ₅ Two or three of which may be N, and A ₁ To A ₅ The remainder of (C) may be C (R) _i )。

[ formula E-2b ]

In formula E-2b, Cbz1 and Cbz2 may each independently be an unsubstituted carbazole group, or a carbazole group substituted with an aryl group having from 6 to 30 ring-forming carbon atoms. L is a radical of an alcohol _b May be a direct bond, a substituted or unsubstituted arylene group having 6 to 30 ring-forming carbon atoms, or a substituted or unsubstituted heteroarylene group having 2 to 30 ring-forming carbon atoms. In the formula E-2b, b may be an integer of 0 to 10, and if b is 2 or greater than 2, a plurality of L _b Each group may independently be a substituted or unsubstituted arylene group having 6 to 30 ring-forming carbon atoms or a substituted or unsubstituted heteroarylene group having 2 to 30 ring-forming carbon atoms.

The compound represented by the formula E-2a or the formula E-2b may be any one selected from the following compound group E-2. However, the compounds shown in the following compound group E-2 are only examples, and the compounds represented by the formula E-2a or the formula E-2b are not limited to the compounds listed in the following compound group E-2.

[ Compound group E-2]

The emission layer EML may further include a material commonly used in the art as a host material. For example, the emissive layer EML may comprise bis [2- (diphenylphosphino) phenyl [ ]]Ether oxide (DP)EPO), 4 '-bis (carbazol-9-yl) -1,1' -biphenyl (CBP), 1, 3-bis (carbazol-9-yl) benzene (mCP), 2, 8-bis (diphenylphosphoryl) dibenzo [ b, d]Furan (PPF), 4' -tris (carbazol-9-yl) -triphenylamine (TCTA) and 1,3, 5-tris (1-phenyl-1H-benzo [ d ]]At least one of imidazole-2-yl) benzene (TPBi) is used as a main material. However, the embodiments are not limited thereto. For example, tris (8-quinolinolato) aluminum (Alq) ₃ ) 9, 10-bis (naphthalen-2-yl) Anthracene (ADN), 2-tert-butyl-9, 10-bis (naphthalen-2-yl) anthracene (TBADN), Distyrylarylene (DSA), 4 '-bis (9-carbazolyl) -2,2' -dimethyl-biphenyl (CDBP), 2-methyl-9, 10-bis (naphthalen-2-yl) anthracene (MADN), hexaphenylcyclotriphosphazene (CP1), 1, 4-bis (triphenylsilyl) benzene (UGH2), hexaphenylcyclotrisiloxane (DPSiO SiO) ₃ ) Octaphenylcyclotetrasiloxane (DPSiO) ₄ ) Etc. may be used as the host material.

The emission layer EML may include a compound represented by the following formula M-a or formula M-b. The compound represented by formula M-a or formula M-b may be used as a phosphorescent dopant material.

[ formula M-a ]

In the formula M-a, Y ₁ To Y ₄ And Z ₁ To Z ₄ May each independently be C (R) ₁ ) Or N, and R ₁ To R ₄ May each independently be a hydrogen atom, a deuterium atom, a substituted or unsubstituted amine group, a substituted or unsubstituted thio group, a substituted or unsubstituted oxy group, a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted alkenyl group having 2 to 20 carbon atoms, a substituted or unsubstituted aryl group having 6 to 30 ring-forming carbon atoms, or a substituted or unsubstituted heteroaryl group having 2 to 30 ring-forming carbon atoms, or may be combined with an adjacent group to form a ring. In the formula M-a, M may be 0 or 1, and n may be 2 or 3. In the formula M-a, n may be 3 if M is 0, and n may be 2 if M is 1.

The compound represented by the formula M-a may be used as a red phosphorescent dopant or a green phosphorescent dopant.

The compound represented by the formula M-a may be any one selected from the following compounds M-a1 through M-a 25. However, the following compounds M-a1 to M-a25 are examples, and the compounds represented by the formula M-a are not limited to the following compounds M-a1 to M-a 25.

Compound M-a1 and compound M-a2 can be used as red dopant materials, and compound M-a3 and compound M-a4 can be used as green dopant materials.

[ formula M-b ]

In the formula M-b, Q ₁ To Q ₄ May each independently be C or N, and C1 to C4 may each independently be a substituted or unsubstituted hydrocarbon ring having 5 to 30 ring-forming carbon atoms or a substituted or unsubstituted heterocyclic ring having 2 to 30 ring-forming carbon atoms. L is a radical of an alcohol ₂₁ To L ₂₄ May each independently be a direct bond,

A substituted or unsubstituted divalent alkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted arylene group having 6 to 30 ring-forming carbon atoms, or a substituted or unsubstituted heteroarylene group having 2 to 30 ring-forming carbon atoms, and e1 to e4 may each independently be 0 or 1. In the formula M-b, R ₃₁ To R ₃₉ May each independently be a hydrogen atom, a deuterium atom, a halogen atom, a cyano group, a substituted or unsubstituted amine group, a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted aryl group having 6 to 30 ring-forming carbon atoms, or a substituted or unsubstituted heteroaryl group having 2 to 30 ring-forming carbon atoms, or may be combined with an adjacent group to form a ring, and d1 to d4 may each independently be an integer of 0 to 4.

The compound represented by the formula M-b may be used as a blue phosphorescent dopant or a green phosphorescent dopant.

The compound represented by the formula M-b may be any one selected from the following compounds. However, the following compounds are examples, and the compound represented by the formula M-b is not limited to the following compounds.

Among the above compounds, R, R ₃₈ And R ₃₉ May each independently be a hydrogen atom, a deuterium atom, a halogen atom, a cyano group, a substituted or unsubstituted amine group, a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted aryl group having 6 to 30 ring-forming carbon atoms, or a substituted or unsubstituted heteroaryl group having 2 to 30 ring-forming carbon atoms.

The emission layer EML may include a compound represented by any one of the following formulas F-a to F-c. Compounds represented by the following formulas F-a to F-c may be used as fluorescent dopant materials.

[ formula F-a ]

In the formula F-a, R is selected from _a To R _j May each independently be a-NAr ₁ Ar ₂ And (4) substitution. R _a To R _j Is not replaced by NAr ₁ Ar ₂ The remainder of the substitution can each independently be a hydrogen atom, a deuterium atom, a halogen atom, a cyano group, a substituted or unsubstituted amine group, a substituted or unsubstituted alkyl group having from 1 to 20 carbon atoms, a substituted or unsubstituted aryl group having from 6 to 30 ring-forming carbon atoms, or a substituted or unsubstituted heteroaryl group having from 2 to 30 ring-forming carbon atoms.

In the radical-NAr ₁ Ar ₂ In Ar ₁ And Ar ₂ May each independently be a substituted or unsubstituted aryl group having 6 to 30 ring-forming carbon atoms or a substituted or unsubstituted heteroaryl group having 2 to 30 ring-forming carbon atoms. For example, Ar ₁ And Ar ₂ At least one of which may be a heteroaryl group containing O or S as a ring-forming atom.

[ formula F-b ]

In the formula F-b, R _a And R _b May each independently be a hydrogen atom, a deuterium atom, a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted alkenyl group having 2 to 20 carbon atoms, a substituted or unsubstituted aryl group having 6 to 30 ring-forming carbon atoms, or a substituted or unsubstituted heteroaryl group having 2 to 30 ring-forming carbon atoms, or may be bonded to an adjacent group to form a ring.

In formula F-b, U and V may each independently be 0 or 1. In the formula F-b, U may represent the number of loops joined at the position U, and V may represent the number of loops joined at the position V. For example, if the number of U or V is 1, the loop represented by U or V may form a joint loop, and if U or V is 0, the loop represented by U or V may not exist. The conjugated ring having a fluorene nucleus of formula F-b may be a compound having four rings if U is 0 and V is 1, or if U is 1 and V is 0. If U and V are both 0, the conjugated ring of the formula F-b having a fluorene core may be a compound having three rings. If U and V are both 1, the conjugated ring of the formula F-b having a fluorene core may be a compound having five rings.

In formula F-b, if U or V is 1, U and V may each independently be a substituted or unsubstituted hydrocarbon ring having 5 to 30 ring-forming carbon atoms or a substituted or unsubstituted heterocyclic ring having 2 to 30 ring-forming carbon atoms.

[ formula F-c ]

In the formula F-c, A ₁ And A ₂ May each independently be O, S, Se or N (R) _m ) And R is _m May be a hydrogen atom, a deuterium atom, a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted aryl group having 6 to 30 ring-forming carbon atoms, or a substituted or unsubstituted heteroaryl group having 2 to 30 ring-forming carbon atoms. In the formula F-c, R ₁ To R ₁₁ May each independently be a hydrogen atom, a deuterium atom, a halogen atom, a cyano group, a substituted or unsubstituted amine group, a substituted or unsubstituted boryl group, a substituted or unsubstituted oxy group, a substituted or unsubstituted thio group, a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted aryl group having 6 to 30 ring-forming carbon atoms, or a substituted or unsubstituted heteroaryl group having 2 to 30 ring-forming carbon atoms, or may be combined with an adjacent group to form a ring.

In the formula F-c, A ₁ And A ₂ Each may be independently combined with a substituent of an adjacent ring to form a conjugated ring. For example, if A ₁ And A ₂ May each independently be N (R) _m )，A ₁ Can be reacted with R ₄ Or R ₅ Combine to form a ring. For example, A ₂ Can be reacted with R ₇ Or R ₈ Combine to form a ring.

In embodiments, the emission layer EML may include styryl derivatives (e.g., 1, 4-bis [2- (3-N-ethylcarbazolyl) vinyl ] benzene (BCzVB), 4- (di-p-tolylamino) -4'- [ (di-p-tolylamino) styryl ] stilbene (DPAVB) and N- (4- ((E) -2- (6- ((E) -4- (diphenylamino) styryl) naphthalen-2-yl) vinyl) phenyl) -N-phenylaniline (N-BDAVBi)), perylene and its derivatives (e.g., 2,5,8, 11-tetra-t-butylperylene (TBP)), pyrene and its derivatives (e.g., 1,1' -dipepyrene, 1, 4-bipyrenylbenzene and 1, 4-bis (N, N-diphenylamino) pyrene)) and the like as a dopant material.

The emission layer EML may include a phosphorescent dopant material. For example, the phosphorescent dopant may use a metal complex containing iridium (Ir), platinum (Pt), osmium (Os), gold (Au), titanium (Ti), zirconium (Zr), hafnium (Hf), europium (Eu), terbium (Tb), or thulium (Tm). For example, iridium (III) bis (4, 6-difluorophenylpyridinato-N, C2') picolinate (FIrpic), iridium (III) bis (2, 4-difluorophenylpyridinato) -tetrakis (1-pyrazolyl) borate (Fir6) or platinum octaethylporphyrin (PtOEP) can be used as phosphorescent dopants. However, the embodiments are not limited thereto.

In the organic electroluminescent device ED of the embodiment as shown in fig. 3 to 6, the electron transport region ETR is provided on the emission layer EML. The electron transport region ETR may include at least one of an electron blocking layer HBL, an electron transport layer ETL, and an electron injection layer EIL. However, the embodiments are not limited thereto.

The electron transport region ETR may have a layer formed using a single material, a layer formed using different materials, or a multi-layer structure having layers formed using different materials.

For example, the electron transport region ETR may have a single-layer structure of the electron injection layer EIL or the electron transport layer ETL, or a single-layer structure formed using an electron injection material and an electron transport material. In embodiments, the electron transport region ETR may have a single-layer structure formed using different materials, or a structure of the electron transport layer ETL/the electron injection layer EIL or the hole blocking layer HBL/the electron transport layer ETL/the electron injection layer EIL stacked from the emission layer EML, without limitation. The thickness of the electron transport region ETR may be, for example, about

To about

The electron transport region ETR may be formed using various methods such as a vacuum deposition method, a spin coating method, a casting method, a langmuir-blodgett (LB) method, an inkjet printing method, a laser printing method, and a Laser Induced Thermal Imaging (LITI) method.

The electron transport region ETR may include a compound represented by the following formula ET-1.

[ formula ET-1]

In the formula ET-1, X ₁ To X ₃ May be N, and X ₁ To X ₃ The remainder of (C) may be C (R) _a )。R _a May be a hydrogen atom, a deuterium atom, a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted aryl group having 6 to 30 ring-forming carbon atoms, or a substituted or unsubstituted heteroaryl group having 2 to 30 ring-forming carbon atoms. In formula ET-1, Ar ₁ To Ar ₃ May each independently be a hydrogen atom, a deuterium atom, a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted aryl group having 6 to 30 ring-forming carbon atoms, or a substituted or unsubstituted heteroaryl group having 2 to 30 ring-forming carbon atoms.

In formula ET-1, a to c may each independently be an integer from 0 to 10. In the formula ET-1, L ₁ To L ₃ May each independently be a direct bond, a substituted or unsubstituted arylene group having 6 to 30 ring-forming carbon atoms, or a substituted or unsubstituted heteroarylene group having 2 to 30 ring-forming carbon atoms. In formula ET-1, L if a to c are 2 or greater than 2 ₁ To L ₃ May each independently be a substituted or unsubstituted arylene group having 6 to 30 ring-forming carbon atoms or a substituted or unsubstituted heteroarylene group having 2 to 30 ring-forming carbon atoms.

If electronThe transport region ETR includes an electron transport layer ETL, and the electron transport region ETR may include an anthracene-based compound. However, the embodiment is not limited thereto, and the electron transport region ETR may include, for example, tris (8-quinolinolato) aluminum (Alq) ₃ ) 1,3, 5-tris [ (3-pyridyl) -phen-3-yl]Benzene, 2,4, 6-tris (3' - (pyridin-3-yl) biphenyl-3-yl) -1,3, 5-triazine, 2- (4- (N-phenylbenzimidazol-1-yl) phenyl) -9, 10-dinaphthylanthracene, 1,3, 5-tris (1-phenyl-1H-benzo [ d ] b]Imidazol-2-yl) benzene (TPBi), 2, 9-dimethyl-4, 7-diphenyl-1, 10-phenanthroline (BCP), 4, 7-diphenyl-1, 10-phenanthroline (Bphen), 3- (4-biphenyl) -4-phenyl-5-tert-butylphenyl-1, 2, 4-Triazole (TAZ), 4- (naphthalen-1-yl) -3, 5-diphenyl-4H-1, 2, 4-triazole (NTAZ), 2- (4-biphenyl) -5- (4-tert-butylphenyl) -1,3, 4-oxadiazole (tBu-PBD), bis (2-methyl-8-quinolinolato-N1, O8) - (1,1' -Biphenyl-4-ylium (BALq), bis (benzoquinolin-10-ylium) beryllium (Bebq) ₂ ) 9, 10-bis (naphthalen-2-yl) Anthracene (ADN), 1, 3-bis [3, 5-bis (pyridin-3-yl) phenyl]Benzene (BmPyPhB) and mixtures thereof, without limitation.

The electron transport region ETR may comprise at least one selected from the following compounds ET1 to ET 36.

The electron transport region ETR may comprise a metal halide (e.g., LiF, NaCl, CsF, RbCl, RbI, CuI, and KI), a lanthanide metal (e.g., Yb), or a co-deposited material of a metal halide and a lanthanide metal. For example, the electron transport region ETR may contain KI: Yb, RbI: Yb, etc. as co-deposited materials. The electron transport region ETR may comprise a metal oxide, such as Li ₂ O and BaO, or lithium 8-hydroxy-quinoline (Liq). However, it is trueThe embodiment is not limited thereto. The electron transport region ETR may also be formed using a mixture material of an electron transport material and an insulating organic metal salt. The insulating organic metal salt may be a material having an energy band gap equal to or greater than about 4 eV. For example, the insulating organic metal salt may include a metal acetate, a metal benzoate, a metal acetoacetate, a metal acetylacetonate, or a metal stearate. However, the embodiments are not limited thereto.

The electron transport region ETR may include a compound of an electron transport region in at least one of the electron injection layer EIL, the electron transport layer ETL, and the hole blocking layer HBL.

If the electron transport region ETR includes the electron transport layer ETL, the thickness of the electron transport layer ETL may be about

To about

For example, the thickness of the electron transport layer ETL may be about

To about

If the thickness of the electron transport layer ETL satisfies the above-described range, satisfactory electron transport properties can be obtained without a significant increase in driving voltage. If the electron transport region ETR includes the electron injection layer EIL, the thickness of the electron injection layer EIL may be about

To about

For example, the thickness of the electron injection layer EIL may be about

To about

If the thickness of the electron injection layer EIL satisfies the above-described range, satisfactory electron injection properties can be obtained without causing a significant increase in driving voltage.

The second electrode EL2 is provided on the electron transport region ETR. The second electrode EL2 may be a common electrode. The second electrode EL2 may be a cathode or an anode, but the embodiment is not limited thereto. For example, if the first electrode EL1 is an anode, the second cathode EL2 may be a cathode, and if the first electrode EL1 is a cathode, the second electrode EL2 may be an anode.

The second electrode EL2 may be a transmissive electrode, a transflective electrode, or a reflective electrode. If the second electrode EL2 is a transmissive electrode, the second electrode EL2 may include a transparent metal oxide, for example, ITO, IZO, ZnO, ITZO, or the like.

If the second electrode EL2 is a transflective or reflective electrode, the second electrode EL2 can comprise Ag, Mg, Cu, Al, Pt, Pd, Au, Ni, Nd, Ir, Cr, Li, Ca, LiF, Mo, Ti, Yb, W, compounds thereof, or mixtures thereof (e.g., AgMg, AgYb). In an embodiment, the second electrode EL2 may have a multi-layer structure including a reflective layer or a semi-reflective layer formed using the above-described materials, and a transparent conductive layer formed using ITO, IZO, ZnO, ITZO, or the like. For example, the second electrode EL2 may contain the foregoing metal material, a combination of two or more metal materials selected from the foregoing metal materials, or an oxide of the foregoing metal material.

Although not shown in the drawings, the second electrode EL2 may be electrically connected to an auxiliary electrode. If the second electrode EL2 is electrically connected to the auxiliary electrode, the resistance of the second electrode EL2 may be reduced.

In an embodiment, the organic electroluminescent device ED may further include a capping layer CPL disposed on the second electrode EL 2. The cover layer CPL may comprise a plurality of layers or a single layer.

In embodiments, the capping layer CPL may include an organic layer or an inorganic layer. For example, if the capping layer CPL comprises an inorganic material, the inorganic material may comprise a baseMetal compounds (e.g. LiF), alkaline earth metal compounds (e.g. MgF) ₂ )、SiON、SiN _x 、SiO _y And so on.

For example, if the capping layer CPL comprises an organic material, the organic material may include α -NPD, NPB, TPD, m-MTDATA, Alq ₃ CuPc, N4, N4, N4', N4' -tetrakis (biphenyl-4-yl) biphenyl-4, 4 '-diamine (TPD15), 4',4 ″ -tris (carbazol-9-yl) triphenylamine (TCTA), etc., or may include an epoxy resin or a (meth) acrylate (e.g., methacrylate). The capping layer CPL may include at least one of the following compounds P1 to P5, but the embodiment is not limited thereto.

The refractive index of the capping layer CPL may be equal to or greater than about 1.6. For example, the refractive index of the capping layer CPL may be equal to or greater than about 1.6 with respect to light in a wavelength range of about 550nm to about 660 nm.

Fig. 7 and 8 are each a schematic cross-sectional view of a display device according to an embodiment. In the explanation of the display device of the embodiment with reference to fig. 7 and 8, a portion overlapping with the explanation of fig. 1 to 6 will not be explained again, and different features will be explained.

Referring to fig. 7, the display apparatus DD according to the embodiment may include a display panel DP including display device layers DP-ED, a light control layer CCL and a color filter layer CFL disposed on the display panel DP.

In the embodiment shown in fig. 7, the display panel DP includes a base layer BS, a circuit layer DP-CL provided on the base layer BS, and a display device layer DP-ED, and the display device layer DP-ED may include an organic electroluminescent device ED.

The organic electroluminescent device ED may include a first electrode EL1, a hole transport region HTR disposed on the first electrode EL1, an emission layer EML disposed on the hole transport region HTR, an electron transport region ETR disposed on the emission layer EML, and a second electrode EL2 disposed on the electron transport region ETR. The same structure of the organic electroluminescent devices of fig. 3 to 6 may be applied to the structure of the organic electroluminescent device ED shown in fig. 7.

Referring to fig. 7, the emission layer EML may be disposed in the opening portion OH defined in the pixel defining layer PDL. For example, the emission layer EML, which is separated by the pixel defining layer PDL and provided corresponding to each of the light emitting regions PXA-R, PXA-G and PXA-B, may emit light in the same wavelength region. In the display device DD of the embodiment, the emission layer EML may emit blue light. Although not shown in the drawings, in an embodiment, the emission layer EML may be provided as a common layer for all light emitting regions PXA-R, PXA-G and PXA-B.

The light control layer CCL may be disposed on the display panel DP. The light control layer CCL may comprise a light converter. The light converter may comprise quantum dots or phosphors. The light converter may convert a wavelength of the provided light and emit the converted light. For example, the light control layer CCL may be a layer comprising quantum dots or a layer comprising phosphors.

The quantum dots may be selected from group II-VI compounds, group III-VI compounds, group I-III-VI compounds, group III-V compounds, group III-II-V compounds, group IV-VI compounds, group IV elements, group IV compounds, and combinations thereof.

The group II-VI compound may be selected from the group consisting of: a binary compound selected from the group consisting of CdSe, CdTe, CdS, ZnS, ZnSe, ZnTe, ZnO, HgS, HgSe, HgTe, MgSe, MgS, and mixtures thereof; a ternary compound selected from the group consisting of CdSeS, CdSeTe, CdSTe, ZnSeS, ZnSeTe, ZnSTe, HgSeS, HgSeTe, HgSTe, CdZnS, CdZnSe, CdZnTe, CdHgS, CdHgSe, CdHgTe, HgZnS, HgZnSe, HgZnTe, MgZnSe, MgZnS, and mixtures thereof; and a quaternary compound selected from the group consisting of HgZnTeS, CdZnSeS, CdZnSeTe, CdZnSTe, CdHgSeS, CdHgSeTe, CdHgSTe, HgZnSeS, HgZnSeTe, and mixtures thereof.

The III-VI compounds can include binary compounds (e.g., In) ₂ S ₃ And In ₂ Se ₃ ) Ternary compounds (e.g. InGaS) ₃ And InGaSe ₃ ) Or an optional combination thereof.

The I-III-VI compound may be selected from ternary compounds selected from the group consisting of AgInS, AgInS ₂ 、CuInS、CuInS ₂ 、AgGaS ₂ 、CuGaS ₂ 、CuGaO ₂ 、AgGaO ₂ 、AgAlO ₂ And mixtures thereof; or quaternary compounds, e.g. AgInGaS ₂ And CuInGaS ₂ 。

The III-V compound may be selected from the group consisting of: a binary compound selected from the group consisting of GaN, GaP, GaAs, GaSb, AlN, AlP, AlAs, AlSb, InN, InP, InAs, InSb, and mixtures thereof; a ternary compound selected from the group consisting of GaNP, GaNAs, GaNSb, GaGaAs, GaPSb, AlNP, AlNAs, AlNSb, AlPAs, AlPSb, InGaP, InAlP, InNP, InNAs, InNSb, InPAs, InPSb, and mixtures thereof; and a quaternary compound selected from the group consisting of GaAlNP, GaAlNAs, GaAlNSb, GaAlPAs, GaAlPSb, gainp, GaInNAs, gainsb, GaInPAs, GaInPSb, InAlNP, InAlNAs, InAlNSb, InAlNAs, InAlPSb, and mixtures thereof. The III-V compound may further comprise a group II metal. For example, InZnP or the like can be selected as the group III-II-V compound.

The group IV-VI compounds may be selected from the group consisting of: a binary compound selected from the group consisting of SnS, SnSe, SnTe, PbS, PbSe, PbTe and mixtures thereof; a ternary compound selected from the group consisting of SnSeS, SnSeTe, SnSTe, PbSeS, PbSeTe, PbSTe, SnPbS, SnPbSe, SnPbTe and mixtures thereof; and a quaternary compound selected from the group consisting of SnPbSSe, SnPbSeTe, SnPbSTe, and mixtures thereof. The group IV element may be selected from the group consisting of Si, Ge and a mixture thereof. The group IV compound may be a binary compound selected from the group consisting of SiC, SiGe, and mixtures thereof.

The binary, ternary, or quaternary compounds may be present in the same particle at a uniform concentration, or may be present in the same particle in a partially different concentration profile. In embodiments, the quantum dots may have a core/shell structure in which one quantum dot surrounds another quantum dot. The interface of the core and the shell may have a concentration gradient in which the concentration of the elements present in the shell decreases towards the core.

In embodiments, the quantum dots may have the core/shell structure described above, including a core comprising nanocrystals and a shell surrounding the core. The shell of the quantum dot may be a protective layer that prevents chemical deformation of the core to maintain semiconductor properties and/or may be a charging layer for imparting electrophoretic properties to the quantum dot. The shell may be a single layer or multiple layers. The interface of the core and the shell may have a concentration gradient in which the elements present in the shell decrease toward the core. Examples of the shell of the quantum dot may include an oxide of a metal or a nonmetal, a semiconductor compound, or a combination thereof.

For example, the oxides of metals or non-metals may include binary compounds, such as SiO ₂ 、Al ₂ O ₃ 、TiO ₂ 、ZnO、MnO、Mn ₂ O ₃ 、Mn ₃ O ₄ 、CuO、FeO、Fe ₂ O ₃ 、Fe ₃ O ₄ 、CoO、Co ₃ O ₄ And NiO; or ternary compounds, e.g. MgAl ₂ O ₄ 、CoFe ₂ O ₄ 、NiFe ₂ O ₄ And CoMn ₂ O ₄ However, the embodiment is not limited thereto.

In an embodiment, the semiconductor compound may include CdS, CdSe, CdTe, ZnS, ZnSe, ZnTe, ZnSeS, ZnTeS, GaAs, GaP, GaSb, HgS, HgSe, HgTe, InAs, InP, InGaP, InSb, AlAs, AlP, AlSb, and the like, but the embodiment is not limited thereto.

The quantum dots may have a full width at half maximum (FWHM) of an emission wavelength spectrum equal to or less than about 45 nm. For example, the quantum dots may have a FWHM of the emission wavelength spectrum equal to or less than about 40 nm. For example, the quantum dots may have a FWHM of the emission wavelength spectrum equal to or less than about 30 nm. Within this range, the color purity or color reproducibility can be improved. Light emitted through the quantum dots may be emitted in all directions, and light viewing angle properties may be improved.

The form of the quantum dot may be a form generally used in the art, without particular limitation. For example, the quantum dots may have a spherical, pyramidal, multi-armed, or cubic shape, or the quantum dots may be in the form of nanoparticles, nanotubes, nanowires, nanofibers, nanoplates, and the like.

The quantum dot may control the color of emitted light according to its particle size, and thus, the quantum dot may have various emission colors, such as blue, red, and green.

The light control layer CCL may include light control components CCP1, CCP2, and CCP 3. The light control components CCP1, CCP2, and CCP3 may be separate from each other.

Referring to fig. 7, the partition pattern BMP may be disposed between the separate light control parts CCP1, CCP2, and CCP3, but the embodiment is not limited thereto. In fig. 7, the partition pattern BMP does not overlap the light control parts CCP1, CCP2, and CCP3, but in an embodiment, at least a portion of the edges of the light control parts CCP1, CCP2, and CCP3 may overlap the partition pattern BMP.

The light control layer CCL may include a first light control part CCP1 including first quantum dots QD1 converting first color light provided by the organic electroluminescent device ED into second color light, a second light control part CCP2 including second quantum dots QD2 converting the first color light into third color light, and a third light control part CCP3 transmitting the first color light.

In an embodiment, the first light control part CCP1 may provide red light as the second color light and the second light control part CCP2 may provide green light as the third color light. The third color control part CCP3 may transmit and provide blue light as the first color light provided by the organic electroluminescent device ED. For example, the first quantum dot QD1 may be a red quantum dot, and the second quantum dot QD2 may be a green quantum dot. The same description above for quantum dots may apply to quantum dots QD1 and QD 2.

The light control layer CCL may further comprise a diffuser SP. The first light control component CCP1 may contain a first quantum dot QD1 and scatterer SP, the second light control component CCP2 may contain a second quantum dot QD2 and scatterer SP, and the third light control component CCP3 may contain no quantum dots but a scatterer SP.

The scatterer SP may be an inorganic particle. For example, the scatterer SP may comprise TiO ₂ 、ZnO、Al ₂ O ₃ 、SiO ₂ And hollow silica. The scatterer SP may comprise TiO ₂ 、ZnO、Al ₂ O ₃ 、SiO ₂ And hollow silica, or may be selected from TiO ₂ 、ZnO、Al ₂ O ₃ 、SiO ₂ And mixtures of two or more materials in hollow silica.

The first light control member CCP1, the second light control member CCP2, and the third light control member CCP3 may each include a matrix resin BR1, BR2, and BR3 in which quantum dots QD1 and QD2 and a scatterer SP are dispersed. In an embodiment, the first light control part CCP1 may include a first quantum dot QD1 and a scatterer SP dispersed in a first matrix resin BR1, the second light control part CCP2 may include a second quantum dot QD2 and a scatterer SP dispersed in a second matrix resin BR2, and the third light control part CCP3 may include a scatterer SP dispersed in a third matrix resin BR 3. Matrix resins BR1, BR2, and BR3 are media in which quantum dots QD1 and QD2 and scatterers SP are dispersed, and may be formed from various suitable resin compositions, each of which may be generally referred to as binders. For example, the matrix resins BR1, BR2, and BR3 may each independently be an acrylic-based resin, a urethane-based resin, a silicone-based resin, an epoxy-based resin, or the like. The matrix resins BR1, BR2, and BR3 may be transparent resins. In embodiments, the first matrix resin BR1, the second matrix resin BR2, and the third matrix resin BR3 may each be the same as or different from each other.

The light control layer CCL may comprise a barrier layer BFL 1. The barrier layer BFL1 may block the permeation of moisture and/or oxygen (hereinafter, will be referred to as "moisture/oxygen"). A barrier layer BFL1 may be disposed on the light control components CCP1, CCP2, and CCP3 to block the exposure of the light control components CCP1, CCP2, and CCP3 to moisture/oxygen. The barrier layer BFL1 can cover the light control components CCP1, CCP2, and CCP 3. A barrier layer BFL2 may be provided between the light control components CCP1, CCP2, and CCP3 and the filters CF1, CF2, and CF 3.

The barrier layers BFL1 and BFL2 may include at least one inorganic layer. For example, the barrier layers BFL1 and BFL2 may be formed by including inorganic materials. For example, the barrier layers BFL1 and BFL2 may be formed by including silicon nitride, aluminum nitride, zirconium nitride, titanium nitride, hafnium nitride, tantalum nitride, silicon oxide, aluminum oxide, titanium oxide, tin oxide, cerium oxide, and silicon oxynitride, or a metal thin film that ensures light transmittance. The barrier layers BFL1 and BFL2 may further include organic layers. The barrier layers BFL1 and BFL2 may be composed of a single layer or multiple layers.

In the display device DD of the embodiment, the color filter layer CFL may be disposed on the light control layer CCL. For example, the color filter layer CFL may be disposed directly on the light control layer CCL. In an embodiment, barrier layer BFL2 may be omitted.

The color filter layer CFL may include a light blocking part BM and filters CF1, CF2, and CF 3. The color filter layer CFL may include a first filter CF1 transmitting the second color light, a second filter CF2 transmitting the third color light, and a third filter CF3 transmitting the first color light. For example, the first filter CF1 may be a red filter, the second filter CF2 may be a green filter, and the third filter CF3 may be a blue filter. Each of the filters CF1, CF2, and CF3 may comprise a polymeric photosensitive resin and a pigment or dye. The first filter CF1 may contain a red pigment or dye, the second filter CF2 may contain a green pigment or dye, and the third filter CF3 may contain a blue pigment or dye. However, the embodiment is not limited thereto, and the third filter CF3 may not contain a pigment or a dye. The third filter CF3 may contain a polymeric photosensitive resin and contain no pigments or dyes. The third filter CF3 may be transparent. The third filter CF3 may be formed using a transparent photosensitive resin.

In an embodiment, the first filter CF1 and the second filter CF2 may be yellow filters. The first filter CF1 and the second filter CF2 may be provided as a single body without distinction.

The light blocking member BM may be a black matrix. The light blocking part BM may be formed by including an organic light blocking material or an inorganic light blocking material (including a black pigment or a black dye). The light blocking member BM may prevent a light leakage phenomenon and may divide the boundaries between the adjacent filters CF1, CF2, and CF 3. In an embodiment, the light blocking member BM may be formed as a blue filter.

Each of the first to third filters CF1, CF2, and CF3 may be disposed to correspond to each of the red light-emitting region PXA-R, the green light-emitting region PXA-G, and the blue light-emitting region PXA-B, respectively.

The base substrate BL may be disposed on the color filter layer CFL. The base substrate BL may provide a base surface on which the color filter layer CFL, the light control layer CCL, and the like are disposed. The base substrate BL may be a glass substrate, a metal substrate, a plastic substrate, or the like. However, the embodiment is not limited thereto, and the base substrate BL may include an inorganic layer, an organic layer, or a composite material layer. Although not shown in the drawings, in the embodiment, the base substrate BL may be omitted.

Fig. 8 is a schematic cross-sectional view illustrating a portion of a display apparatus according to an embodiment. In fig. 8, a schematic cross-sectional view corresponding to a part of the display panel DP in fig. 7 is shown. In the display device DD-TD of the embodiment, the organic electroluminescent device ED-BT may include a plurality of light emitting structures OL-B1, OL-B2, and OL-B3. The organic electroluminescent device ED-BT may include a first electrode EL1 and an oppositely disposed second electrode EL2, and a plurality of light emitting structures OL-B1, OL-B2, and OL-B3 stacked in order in the thickness direction and provided between the first electrode EL1 and the second electrode EL 2. Each of the light emitting structures OL-B1, OL-B2, and OL-B3 may include an emission layer EML (fig. 7), and a hole transport region HTR and an electron transport region ETR (fig. 7) between which the emission layer EML is disposed.

For example, the organic electroluminescent devices ED-BT included in the display apparatus DD-TD of the embodiment may be organic electroluminescent devices of a serial structure including a plurality of emission layers.

In the embodiment shown in fig. 8, the light emitted by the light emitting structures OL-B1, OL-B2 and OL-B3 may all be blue light. However, the embodiment is not limited thereto, and wavelength regions of light emitted by the light emitting structures OL-B1, OL-B2, and OL-B3 may be different from each other. For example, the organic electroluminescent device ED-BT including a plurality of light emitting structures OL-B1, OL-B2, and OL-B3 that emit light in different wavelength regions may emit white light.

The charge generation layers CGL1 and CGL2 may be disposed between adjacent light emitting structures OL-B1, OL-B2, and OL-B3. The charge generation layers CGL1 and CGL2 may each independently include a p-type charge generation layer and/or an n-type charge generation layer.

Hereinafter, embodiments will be explained with reference to example compounds and comparative compounds. These embodiments are merely examples to aid understanding of the present disclosure, and the scope of the present disclosure is not limited thereto.

[ examples ]

1. Synthesis of polycyclic Compounds

The polycyclic compounds according to the embodiments will be explained with reference to the synthetic methods of compound 1, compound 2, compound 3, compound 89, compound 411, compound 249, and compound 331 in compound group 1. The synthesis method of the polycyclic compound explained below is an embodiment, and the synthesis method of the polycyclic compound of the embodiment is not limited thereto.

< Synthesis of Compound 1 >

Polycyclic compound 1 according to the embodiment can be synthesized by, for example, the procedure in reaction 1 below.

[ reaction 1]

(1) Synthesis of Compound A

Under Ar atmosphere, 1, 3-dibromo-5-chlorobenzene (25.0g, 92.5mmol), diphenylamine (31.3g, 185mmol), tris (dibenzylideneacetone) dipalladium (0) -chloroform adduct (Pd) ₂ (dba) ₃ CHCl ₃ 1.78g, 1.94mmol), 2-dicyclohexylphosphino-2 ',6' -dimethoxybiphenyl (SPhos, 1.59g, 3.88mmol) and tBuONa (27.1g, 282mmol) were added to 400ml of toluene and the mixture was stirred inThe reaction was carried out at about 80 ℃ for about 6 hours. After cooling, water was added, celite was filtered, the liquid layers were separated and the organic layer was concentrated. The crude product was isolated by silica gel column chromatography to obtain compound a (33.1g, yield 80%). Compound a has a molecular weight of 447 as measured by FAB MS.

(2) Synthesis of Compound B

Under Ar atmosphere, compound A (33.0g, 73.8mmol), compound F (12.5g, 73.8mmol), Pd (dba) ₂ (1.54g，2.68mmol)、P(t-Bu) ₃ HBF ₄ (1.56g, 5.40mmol) and tBuONa (9.68g, 100mmol) were added to 300ml of toluene and heated and stirred at about 80 ℃ for about 2 hours. Water was added, celite filtered, the liquid layer separated and the organic layer concentrated. The crude product was isolated by silica gel column chromatography to obtain compound B (28.0g, yield 65%). The molecular weight of compound B was 745 as measured by FAB MS.

(3) Synthesis of Compound C

Under Ar atmosphere, 1, 3-dibromo-5-fluorobenzene (50.0g, 197mmol), N-phenyl-biphenyl-2-amine (70.0g, 414mmol), Pd (dba) ₂ (5.66g，9.85mmol)、P(t-Bu) ₃ HBF ₄ (2.86g, 9.85mmol) and tBuONa (66.2g, 689mmol) were added to 700ml of toluene and heated and stirred at about 80 ℃ for about 2 hours. Water was added, celite filtered, the liquid layer separated and the organic layer concentrated. The crude product was isolated by silica gel column chromatography to obtain compound C (74.6g, 88% yield). The molecular weight of compound C was 583 as measured by FAB MS.

(4) Synthesis of Compound D

Under Ar atmosphere, compound C (25.0g, 58.0mmol), 3-chlorobenzenethiol (10.9g, 75.5mmol) and K ₃ PO ₄ (49.3g, 232mmol) was added to 1-methyl-2-pyrrolidone (NMP, 250ml) and heated and stirred at about 170 ℃ for about 10 hours. After cooling, water and toluene were added, the liquid layers were separated and the organic layer was concentrated. The crude product was isolated by silica gel column chromatography to obtain compound D (19.3g, yield 60%). The molecular weight of compound D was 707 by FAB MS.

(5) Synthesis of Compound E

By carrying out the same method as the synthesis of compound B, compound E (29.7g, yield 79%) was obtained from compound D (19.0g, 34.2mmol) and compound B (15.3g, 34.2 mmol). Compound E has a molecular weight of 1416 as measured by FAB MS.

(6) Synthesis of Compound 1

Compound E (29.0g, 26.4mmol) was dissolved in 1, 2-dichlorobenzene (ODCB, 380ml) under Ar atmosphere, and BBr was added ₃ (39.7g, 158mmol) was added thereto followed by heating and stirring at about 180 ℃ for about 10 hours. After cooling to room temperature, N-diisopropylethylamine (110g, 851mmol) was added, water was added, filtration with celite was performed, the liquid layer was separated, and the organic layer was concentrated. The crude product was isolated by silica gel column chromatography to obtain compound 1(8.82g, yield 30%). Compound 1 has a molecular weight of 1431 as measured by FAB MS. After purification by sublimation (395 ℃, 7.5X 10) ^-3 Pa) purification, the device was evaluated.

< Synthesis of Compound 2 >

Polycyclic compound 2 according to an embodiment can be synthesized, for example, by the following procedure in reaction 2.

[ reaction 2]

(1) Synthesis of Compound F

Compound F (20.0g, yield 85%) was obtained by performing the same method as the synthesis of compound B. Compound F had a molecular weight of 636 as measured by FAB MS.

By carrying out the same method as the synthesis of compound B, compound H (21.0G, yield 76%) was obtained from compound G (13.4G, 24.1mmol) and compound F (15.3G, 24.1 mmol). Compound H had a molecular weight of 1154 as measured by FAB MS.

(2) Synthesis of Compound 2

By carrying out the same method as the synthesis of compound 1, compound 2(4.1g, yield 20%) was obtained from compound H (20.0g, 17.3 mmol). Molecular weight of Compound 2 by FAB MS measurementIs 1170. After purification by sublimation (390 ℃, 6.5X 10) ^-3 Pa) purification, the device was evaluated.

< Synthesis of Compound 3 >

Polycyclic compound 3 according to an embodiment can be synthesized by, for example, the procedure in reaction 3 below.

[ reaction 3]

(1) Synthesis of Compound I

Compound I (30.0g, yield 82%) was obtained by performing the same method as the synthesis of compound B. The molecular weight of compound I was 655 as measured by FAB MS.

(2) Synthesis of Compound J

Under Ar atmosphere, compound I (28.0g, 42.7mmol), 1-fluoro-3-iodobenzene (75.8g, 341.5mmol), CuI (8.1g, 42.7mmol) and K ₂ CO ₃ (29.5g, 213mmol) was heated and stirred at about 190 ℃ for about 72 hours. After cooling, toluene and water were added, filtration through celite was performed, and the organic layer was concentrated. The crude product was isolated by silica gel column chromatography to obtain compound J (16.6g, yield 52%). Compound J has a molecular weight of 749 as measured by FAB MS.

(3) Synthesis of Compound K

By carrying out the same method as the synthesis of compound D, compound K (19.1g, yield 62%) was obtained from compound J (25.0g, 33.3mmol) and 3, 5-dichlorothiophenol (7.76g, 43.3 mmol). The molecular weight of compound K was 908 as measured by FAB MS.

(4) Synthesis of Compound L

By carrying out the same method as the synthesis of compound C, compound L (22.1g, yield 90%) was obtained from compound K (19.0g, 20.9mmol) and diphenylamine (7.42g, 43.9 mmol). The molecular weight of compound L was 1174 as measured by FAB MS.

(5) Synthesis of Compound 3

By carrying out the same method as the synthesis of Compound 1, from Compound L (22.0)g, 18.7mmol) to yield compound 3(3.34g, 15% yield). The molecular weight of compound 3 was 1190 as measured by FAB MS. After purification by sublimation (395 ℃, 8.8X 10) ^-3 Pa) purification, the device was evaluated.

< Synthesis of Compound 89 >

Polycyclic compound 89 according to embodiments can be synthesized, for example, by the procedure in reaction 4 below.

[ reaction 4]

(1) Synthesis of Compound M

By carrying out the same method as the synthesis of compound C, compound M (33.2g, yield 91%) was obtained from 1-bromo-3, 5-difluorobenzene (25.0g, 129mmol) and diphenylamine (24.1g, 142 mmol). The molecular weight of compound M was 281 as measured by FAB MS.

(2) Synthesis of Compound N

By carrying out the same method as the synthesis of compound D, compound N (20.7g, yield 64%) was obtained from compound M (25.0g, 88.8mmol) and phenol (10.9g, 115 mmol). The molecular weight of compound N was 355 as measured by FAB MS.

(3) Synthesis of Compound O

By carrying out the same method as the synthesis of compound D, compound O (21.6g, yield 80%) was obtained from compound N (20.0g, 56.3 mmol). The molecular weight of compound O was 480 as measured by FAB MS.

(4) Synthesis of Compound P

By carrying out the same method as the synthesis of compound H, compound P (33.6g, yield 75%) was obtained from compound O (21.0g, 43.8 mmol). Compound P has a molecular weight of 1023 as measured by FAB MS.

(5) Synthesis of Compound 89

By carrying out the same method as the synthesis of compound 1, compound 89(11.7g, yield 35%) was obtained from compound P (33.0g, 32.3 mmol). Compound 89 has a molecular weight of 1038 as measured by FAB MS. In the process of passing throughHua purified (395 ℃, 9.7X 10) ^-3 Pa) purification, the device was evaluated.

< Synthesis of Compound 411 >

Polycyclic compound 411 according to embodiments can be synthesized, for example, by the procedure in reaction 5 below.

[ reaction 5]

(1) Synthesis of Compound Q

By carrying out the same method as the synthesis of compound D, compound Q (17.8g, yield 54%) was obtained from compound M (25.0g, 88.8mmol) and thiophenol (12.7g, 116 mmol). The molecular weight of compound Q was 371 as measured by FAB MS.

(2) Synthesis of Compound R

By carrying out the same method as the synthesis of compound D, compound R (16.3g, yield 72%) was obtained from compound Q (17.0g, 45.8 mmol). Compound R has a molecular weight of 496 as measured by FAB MS.

(3) Synthesis of Compound S

By carrying out the same method as the synthesis of compound H, compound S (25.8g, yield 77%) was obtained from compound R (16.0g, 32.2 mmol). The molecular weight of compound S was 1039 as measured by FAB MS.

(4) Synthesis of Compound 411

By carrying out the same method as the synthesis of compound 1, compound 411(11.4g, yield 45%) was obtained from compound S (25.0g, 24.4 mmol). Compound 411 has a molecular weight of 1054 as measured by FAB MS. After purification by sublimation (395 ℃, 7.7X 10) ^-3 Pa) purification, the device was evaluated.

< Synthesis of Compound 249 >

Polycyclic compound 249 according to an embodiment can be synthesized, for example, by the steps in reaction 6 below.

[ reaction 6]

(1) Synthesis of Compound T

Compound T (20.0g, yield 80%) was obtained by performing the same method as the synthesis of compound B. The molecular weight of compound T was 581 as measured by FAB MS.

(2) Synthesis of Compound U

By carrying out the same method as the synthesis of compound J, compound U (13.6g, yield 65%) was obtained from compound T (18.0g, 31.0mmol) and 1-fluoro-3-iodobenzene (55.0g, 248 mmol). The molecular weight of compound U is 675 as measured by FAB MS.

(3) Synthesis of Compound V

By carrying out the same method as the synthesis of compound D, compound V (12.0g, yield 75%) was obtained from compound U (13.0g, 19.3mmol) and 3, 5-dichlorobenzene (4.48g, 25.0 mmol). The molecular weight of compound V was 834 as measured by FAB MS.

(4) Synthesis of Compound W

By carrying out the same method as the synthesis of compound C, compound W (13.3g, yield 92%) was obtained from compound V (11.0g, 13.2mmol) and diphenylamine (4.67g, 27.7 mmol). The molecular weight of compound W, as measured by FAB MS, was 1099.

(5) Synthesis of Compound 249

By carrying out the same method as the synthesis of compound 1, compound 249(2.38g, yield 18%) was obtained from compound W (13.0g, 11.8 mmol). Compound 249 has a molecular weight of 1115 as measured by FAB MS. After purification by sublimation (380 ℃, 7.8X 10) ^-3 Pa) purification, the device was evaluated.

< Synthesis of Compound 331 >

Polycyclic compound 331 according to an embodiment can be synthesized, for example, by the following procedure in reaction 7.

[ reaction 7]

(1) Synthesis of Compound X

Compound X (18.0g, yield 72%) was obtained by performing the same method as the synthesis of compound B. Compound X has a molecular weight of 597 as measured by FAB MS.

(2) Synthesis of Compound Y

By carrying out the same method as the synthesis of compound J, compound Y (14.7g, yield 75%) was obtained from compound X (17.0g, 28.5mmol) and 1-fluoro-3-iodobenzene (50.6g, 228 mmol). The molecular weight of compound Y was 691 as measured by FAB MS.

(3) Synthesis of Compound Z

By carrying out the same method as the synthesis of compound D, compound Z (15.2g, yield 88%) was obtained from compound Y (14.0g, 20.3mmol) and 3, 5-dichlorothiophenol (4.72g, 26.3 mmol). The molecular weight of compound Z was 850 as measured by FAB MS.

(4) Synthesis of Compound AA

By carrying out the same method as the synthesis of compound C, compound AA (17.1g, yield 87%) was obtained from compound Z (15.0g, 17.7mmol) and diphenylamine (6.27g, 37.1 mmol). The molecular weight of compound AA was 1115 as measured by FAB MS.

(5) Synthesis of Compound 331

By carrying out the same method as the synthesis of compound 1, compound 331(1.84g, yield 11%) was obtained from compound AA (16.5g, 14.8 mmol). Compound 331 has a molecular weight of 1131 as measured by FAB MS. After purification by sublimation (380 ℃, 6.8X 10) ^-3 Pa) purification, the device was evaluated.

1. Production and evaluation of organic electroluminescent device

(production of organic electroluminescent device)

The following example compounds and comparative compounds were used as materials for the emission layer to fabricate an organic electroluminescent device.

[ example Compounds ]

[ comparative Compound ]

On a glass substrate, will have a thickness of about

The ITO of thickness of (a) was patterned, washed with ultrapure water and treated with UV ozone for about 10 minutes. Depositing HAT-CN to about

Of alpha-NPD to a thickness of about

And depositing mCP to a thickness of about

To form a hole transport region.

Co-depositing a polycyclic compound of an embodiment or a comparative compound with mCBP in a weight ratio of 1:99 to form a compound having a molecular weight of about

Thereby forming an emissive layer.

Forming a layer on the emitting layer using TPBi up to about

And forming a layer using LiF to a thickness of about

To form an electron transport region. Forming the second electrode using aluminum (Al) to about

Is measured.

(evaluation of Properties of organic electroluminescent device)

The measured values according to examples 1 to 7 and comparative examples 1 to 6 are shown in table 1 below. Roll-off is controlled by (1 cd/m) ³ External quantum efficiency of (2) - (1000 cd/m) ³ )/(1cd/m ³ External quantum efficiency) × 100. Maximum emission efficiency (EQE) _max1000nit ) Is at about 10mA/cm ² The lower measured value, and the relative lifetime means a relative lifetime value when the half-life of comparative example 3 is set to 1. Luminescence decay of delayed fluorescence represents 1% of the example compound or the comparative compound: measurement of thin film Photoluminescence (PL) of mCBP (20 nm). Calculating an inverse intersystem crossing rate constant (k) from the luminescence decay and the luminescence quantum efficiency _RISC )。

[ Table 1]

Referring to table 1, it can be confirmed that examples 1 to 7 achieve both long life and high efficiency when compared to comparative examples 1 to 6.

Polycyclic compounds according to embodiments introduce sulfur atoms in the core structure and may increase the reverse intersystem crossing rate constant (k) _RISC ). By including one or more than one substituent at the ortho-position of the phenyl group bonded to nitrogen to increase the volume of the molecule, triplet-triplet annihilation (TTA) or singlet-triplet annihilation (STA), which is one of factors showing roll-off, can be suppressed and a low roll-off value is exhibited. Therefore, the polycyclic compound according to the embodiment can effectively suppress roll-off, and it can be confirmed that high efficiency and long life of the organic electroluminescent device are achieved.

The organic electroluminescent device according to the embodiment has excellent efficiency.

The polycyclic compound according to the embodiment may be used as a material of an emission layer of an organic electroluminescent device, and the efficiency of the organic electroluminescent device may be improved by using the polycyclic compound according to the embodiment.

Embodiments have been disclosed herein, and although terms are used, they are used and are to be interpreted in a generic and descriptive sense only and not for purposes of limitation. In some instances, features, characteristics and/or elements described with respect to an embodiment may be used alone or in combination with features, characteristics and/or elements described with respect to other embodiments, unless specifically indicated otherwise, as will be apparent to one of ordinary skill in the art. Accordingly, it will be understood by those of ordinary skill in the art that various changes in form and details may be made therein without departing from the spirit and scope of the present disclosure as set forth in the following claims.

Claims

1. An organic electroluminescent device comprising:

a first electrode;

a hole transport region disposed on the first electrode;

an emissive layer disposed on the hole transport region;

an electron transport region disposed on the emission layer; and

a second electrode disposed on the electron transport region, wherein

The emission layer includes a polycyclic compound represented by formula 1:

[ formula 1]

Wherein in the formula 1, the first and second groups,

X ₁ and X ₂ Each independently is O, S or N (R) ₇ )，

e and f are each independently an integer from 0 to 4,

g is an integer of 0 to 2,

h is an integer of 0 to 3,

R ₁ to R ₄ 、R _5-1 To R _5-3 And R _6-1 To R _6-3 Each independently is a hydrogen atom, a deuterium atom, a halogen atom, a nitro group, a cyano group, a hydroxyl group, a substituted or unsubstituted amine groupA group, a substituted or unsubstituted thiol group, a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted aryl group having 6 to 30 ring-forming carbon atoms, or a substituted or unsubstituted heteroaryl group having 2 to 30 ring-forming carbon atoms, or is bonded to an adjacent group to form a ring,

R ₇ is a hydrogen atom, a deuterium atom, a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted aryl group having 6 to 30 ring-forming carbon atoms, or a substituted or unsubstituted heteroaryl group having 2 to 30 ring-forming carbon atoms, or is bonded to an adjacent group to form a ring, and

Y ₁ and Y ₂ Each independently is a hydrogen atom, a deuterium atom, a substituted or unsubstituted alkyl group having from 6 to 20 carbon atoms, a substituted or unsubstituted aryl group having from 6 to 30 ring-forming carbon atoms, or a substituted or unsubstituted heteroaryl group having from 2 to 30 ring-forming carbon atoms, and

Y ₁ and Y ₂ Is a substituted or unsubstituted alkyl group having 6 to 20 carbon atoms, a substituted or unsubstituted aryl group having 6 to 30 ring-forming carbon atoms, or a substituted or unsubstituted heteroaryl group having 2 to 30 ring-forming carbon atoms.

2. The organic electroluminescent device according to claim 1, wherein the emission layer emits delayed fluorescence.

3. The organic electroluminescent device as claimed in claim 1, wherein

The emission layer is a delayed fluorescence emission layer comprising a first compound and a second compound, an

The first compound includes the polycyclic compound.

4. The organic electroluminescent device according to claim 1, wherein the emission layer is a thermally activated delayed fluorescence emission layer that emits light having a wavelength of 430nm to 480 nm.

5. The organic electroluminescent device as claimed in claim 1, wherein

X ₁ And X ₂ Is N (R) ₇ ) And an

R ₇ Is a substituted or unsubstituted aryl group having 6 to 30 ring-forming carbon atoms or a substituted or unsubstituted heteroaryl group having 2 to 30 ring-forming carbon atoms.

6. The organic electroluminescent device according to claim 1, wherein the polycyclic compound represented by formula 1 is represented by one of formulae 2-1 to 2-5:

[ formula 2-1]

[ formula 2-2]

[ formulas 2 to 3]

[ formulae 2 to 4]

[ formulas 2 to 5]

Wherein in formulae 2-1 to 2-5,

Ar _1-1 and Ar _1-2 Each independently is a substituted or unsubstituted aryl group having 6 to 30 ring-forming carbon atoms or a substituted or unsubstituted heteroaryl group having 2 to 30 ring-forming carbon atoms, and

R ₁ to R ₄ 、R _5-1 To R _5-3 、R _6-1 To R _6-3 、Y ₁ 、Y ₂ And e to h are the same as defined with respect to formula 1.

7. The organic electroluminescent device as claimed in claim 6, wherein Ar is Ar _1-1 And Ar _1-2 Each independently is a group represented by one of formulae 5-1 to 5-3:

[ formula 5-1]

[ formula 5-2]

[ formulas 5 to 3]

Wherein in formulae 5-1 to 5-3,

R _a1 to R _a5 Each independently is a hydrogen atom, a deuterium atom, a halogen atom, a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted aryl group having 6 to 30 ring-forming carbon atoms, or a substituted or unsubstituted heteroaryl group having 2 to 30 ring-forming carbon atoms,

m1, m3 and m5 are each independently an integer of 0 to 5,

m2 is an integer from 0 to 9,

m4 is an integer of 0 to 3, an

Denotes the binding site to the adjacent atom.

8. The organic electroluminescent device as claimed in claim 1, wherein R is _5-1 To R _5-3 And R _6-1 To R _6-3 Is a substituted amine group.

9. The organic electroluminescent device according to claim 1, wherein the polycyclic compound represented by formula 1 is represented by formula 3-1 or formula 3-2:

[ formula 3-1]

[ formula 3-2]

Wherein in formula 3-1 and formula 3-2,

Ar _3-1 、Ar _3-2 、Ar _4-1 and Ar _4-2 Each independently a substituted or unsubstituted aryl group having from 6 to 30 ring-forming carbon atoms, and

X ₁ 、X ₂ 、R ₁ to R ₄ 、R _5-1 To R _5-3 、R _6-1 To R _6-3 、Y ₁ 、Y ₂ And e to h are the same as defined with respect to formula 1.

10. The organic electroluminescent device according to claim 1, wherein the polycyclic compound represented by formula 1 is represented by formula 4:

[ formula 4]

Wherein in the formula 4, the first and second groups,

X ₁ 、X ₂ 、R ₁ to R ₄ 、R _5-1 、R _5-3 、R _6-1 、R _6-3 、Y ₁ 、Y ₂ And e to h are the same as defined with respect to formula 1.

11. The organic electroluminescent device as claimed in claim 10, wherein Ar _3-1 、Ar _3-2 、Ar _4-1 And Ar _4-2 Each independently is a substituted or unsubstituted aryl group having from 6 to 18 ring-forming carbon atoms.

12. The organic electroluminescent device according to claim 1, wherein the polycyclic compound represented by formula 1 is one selected from compound group 1:

[ Compound group 1]

13. A polycyclic compound represented by formula 1:

[ formula 1]

Wherein in the formula 1, the first and second groups,

X ₁ and X ₂ Each independently is O, S or N (R) ₇ )，

e and f are each independently an integer from 0 to 4,

g is an integer of 0 to 2,

h is an integer of 0 to 3,

R ₁ to R ₄ 、R _5-1 To R _5-3 And R _6-1 To R _6-3 Each independently is a hydrogen atom, a deuterium atom, a halogen atom, a nitro group, a cyano group, a hydroxyl group, a substituted or unsubstituted amine group, a substituted or unsubstituted thiol group, a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted aryl group having 6 to 30 ring-forming carbon atoms, or a substituted or unsubstituted heteroaryl group having 2 to 30 ring-forming carbon atoms, or is bonded to an adjacent group to form a ring,