Organic electroluminescent element and electronic device

Abstract

An organic electroluminescent element, wherein a first light-emitting unit, a first charge generation layer, a second light-emitting unit, a second charge generation layer, and a third light-emitting unit are included in this order from the anode side between an anode and a cathode, the second charge generation layer has an N layer on the anode side and a P layer on the cathode side, the third light-emitting layer includes a compound having blue fluorescent light-emitting properties, at least one of the first light-emitting layer and the second light-emitting layer includes a compound having blue fluorescent light-emitting properties, the third light-emitting unit further has a hole transport region between the second charge generation layer and the third light-emitting layer, the hole transport region is in contact with the second charge generation layer, and the thickness of the hole transport region is 5 nm or more and 40 nm or less, and is thinner than the thickness of the N layer.

Description

Technical Field

[0001] This invention relates to organic electroluminescent elements and electronic devices. Background Technology

[0002] Organic electroluminescent devices (hereinafter sometimes referred to as "organic EL devices") are known to have light-emitting units containing a light-emitting layer between the anode and the cathode, which emit light by utilizing the exciton energy generated by the recombination of holes and electrons injected into the light-emitting layer.

[0003] In recent years, research has been conducted on organic EL devices that utilize a charge-generating layer to stack multiple light-emitting units and connect them in series. Such device configurations are sometimes referred to as tandem type.

[0004] Series-connected organic EL devices are considered to emit light at lower voltages compared to non-series-connected organic EL devices. Therefore, series-connected organic EL devices have attracted attention as a technology that can achieve longer device lifetimes.

[0005] For example, Patent Document 1 discloses an organic electroluminescent element comprising at least a first light-emitting unit including a first light-emitting unit including a first light-emitting layer and a second light-emitting unit including a second light-emitting layer, and a charge-generating layer disposed between the first light-emitting unit and the second light-emitting unit, wherein the thickness of the hole transport layer in the second light-emitting unit is 10% or more and 25% or less relative to the total thickness of the second light-emitting unit.

[0006] Existing technical documents

[0007] Patent documents

[0008] Patent Document 1: Japanese Patent Application Publication No. 2015-153523 Summary of the Invention

[0009] The problem the invention aims to solve

[0010] However, in recent years, there has been a search for further low-voltage driving and improved lifetime in tandem organic EL devices. Among these, blue emission is considered challenging in the field of organic EL devices; therefore, especially in organic EL devices with blue emission layers, there is a search for driving at low voltage and improving lifetime.

[0011] Although the organic electroluminescent element described in Patent Document 1 discloses an element with a blue light-emitting layer, its driving voltage and lifetime have not been adequately studied.

[0012] The purpose of this invention is to provide an organic electroluminescent element that can reduce the driving voltage and increase the lifespan, and an electronic device equipped with the organic electroluminescent element.

[0013] means for solving problems

[0014] According to one aspect of the present invention, an organic electroluminescent element is provided, comprising an anode, a cathode, a first light-emitting unit having a first light-emitting layer, a first charge-generating layer, a second light-emitting unit having a second light-emitting layer, a second charge-generating layer, and a third light-emitting unit having a third light-emitting layer. The first light-emitting unit, the first charge-generating layer, the second light-emitting unit, the second charge-generating layer, and the third light-emitting unit are sequentially arranged from the anode side between the anode and the cathode. The second charge-generating layer has an N-layer on the anode side and a P-layer on the cathode side. The third light-emitting layer comprises a blue fluorescent compound. At least one of the first and second light-emitting layers comprises a blue fluorescent compound. The third light-emitting unit further has a hole transport region between the second charge-generating layer and the third light-emitting layer. The hole transport region of the third light-emitting unit is in contact with the second charge-generating layer. The thickness of the hole transport region of the third light-emitting unit is 5 nm or more and 40 nm or less, and is thinner than the thickness of the N-layer.

[0015] According to one aspect of the present invention, an electronic device is provided, which is equipped with the organic electroluminescent element of one aspect of the present invention described above.

[0016] According to one aspect of the present invention, an organic EL element capable of reducing driving voltage and increasing lifespan, and an electronic device equipped with the organic EL element, can be provided. Attached Figure Description

[0017] Figure 1 This is a diagram showing the general configuration of an example of an organic EL element according to the first embodiment.

[0018] Figure 2 This is a diagram illustrating the optical distance between the reflective electrode and the light-emitting center of each light-emitting layer for the organic EL element of the first embodiment.

[0019] Figure 3 This is a diagram showing the general configuration of an example of an organic EL element according to the second embodiment. Detailed Implementation

[0020] [First Implementation]

[0021] The organic EL element of the first embodiment is a series-connected organic EL element having three light-emitting units. Examples of the organic EL element in this embodiment include the following configurations.

[0022] "Anode / First Light-Emitting Unit / First Charge Generation Layer / Second Light-Emitting Unit / Second Charge Generation Layer / Third Light-Emitting Unit / Cathode"

[0023] Each light-emitting unit and each charge-generating layer has an organic layer. This organic layer is composed of multiple layers of organic compounds stacked together. The organic layer may also contain inorganic compounds.

[0024] In this embodiment, examples are given that have Figure 1 The following description uses a series-connected organic EL element 1 as an example. The organic EL element 1 is constructed by sequentially stacking an anode 12, a first light-emitting unit 13, a first charge-generating layer 14, a second light-emitting unit 15, a second charge-generating layer 16, a third light-emitting unit 17, and a cathode 18 on a substrate 11.

[0025] The detailed structure of each light-emitting unit and each charge-generating layer is described below.

[0026] First light-emitting unit 13: First hole transport region 131 (thickness d1)

[0027] First light-emitting layer 132

[0028] First electron transport region 133

[0029] First charge generation layer 14: First N-layer 141

[0030] First P layer 142

[0031] Second light-emitting unit 15: Second hole transport region 151 (thickness d2)

[0032] Second light-emitting layer 152

[0033] Second electron transport region 153

[0034] Second charge generation layer 16: Second N layer 161 (thickness d) N )

[0035] Second P layer 162

[0036] Third light-emitting unit 17: Third hole transport region 171 (thickness d3)

[0037] Third light-emitting layer 172

[0038] Third electron transmission region 173

[0039] In this embodiment, the third luminescent layer 172 contains a blue fluorescent compound. At least one of the first luminescent layer 132 and the second luminescent layer 152 also contains a blue fluorescent compound.

[0040] That is, the third light-emitting layer 172 is a blue fluorescent light-emitting layer. At least one of the first light-emitting layer 132 and the second light-emitting layer 152 is a blue fluorescent light-emitting layer.

[0041] The third hole transport region 171 is connected to the second charge generation layer 16.

[0042] The thickness d3 of the third hole transport region 171 is greater than 5 nm and less than 40 nm, and is greater than the thickness d3 of the second N layer 161. N Thin.

[0043] The inventors have discovered that the organic EL element configured as described above is capable of reducing the driving voltage and increasing its lifespan. This is believed to be based on the following reasons.

[0044] In the past, in organic EL devices with three light-emitting units, from the perspective of utilizing the light interference effect, the third hole transport region was often made relatively thick.

[0045] In such a device configuration, the interface between the third hole transport region and the third light-emitting layer is prone to degradation. As a result, a tendency to increase the driving voltage and a tendency to reduce the device lifetime are observed.

[0046] It is speculated that this is because, due to the thickness of the third hole transport region, the hole supply from the second charge generation layer to the third light-emitting layer becomes insufficient, resulting in the recombination region of the third light-emitting layer being biased towards the hole transport region side.

[0047] Therefore, in this embodiment, the third hole transport region is connected to the second charge generation layer, and the thickness of the third hole transport region is set to be relatively thin, between 5 nm and 40 nm. Alternatively, considering the resistance of each organic layer, the thickness of the N layer of the second charge generation layer is set to be thicker than the thickness of the third hole transport region.

[0048] It is believed that this promotes the supply of holes from the second charge generation layer to the third light-emitting layer, allowing the recombination region of the third light-emitting layer, previously biased towards the hole transport region, to extend towards the electron transport region. Consequently, it is believed that the degradation of the interface between the third hole transport region and the third light-emitting layer is suppressed.

[0049] Therefore, the organic EL element according to this embodiment can reduce the driving voltage and increase the lifespan (hereinafter also referred to as "the effect of this embodiment").

[0050] Furthermore, according to this embodiment, by satisfying the formulas for optical interference by the third light-emitting unit (specifically, mathematical formulas (1-3) and (2-3) described later), the luminous efficiency of blue fluorescence emission can be improved.

[0051] That is, according to one embodiment of this invention, the driving voltage can be reduced, the lifespan can be increased, and the luminous efficiency can be improved.

[0052] Figure 1 In the process, the first light-emitting unit 13, the second light-emitting unit 15, and the third light-emitting unit 17 respectively have a first electron transmission region 133, a second electron transmission region 153, and a third electron transmission region 173, but each light-emitting unit may not have an electron transmission region.

[0053] From the viewpoint of further demonstrating the effect of this embodiment, it is preferable that the first light-emitting unit 13, the second light-emitting unit 15, and the third light-emitting unit 17 each have a first electron transmission region 133, a second electron transmission region 153, and a third electron transmission region 173, respectively.

[0054] Here, the hole transport region refers to the region where holes move. The hole mobility μ within the hole transport region... H Preferably 10 -6 cm 2 / [V·s] above.

[0055] The hole transport region can be single-layered or multi-layered.

[0056] In addition to hole transport layers, other layers that constitute the hole transport region include hole injection layers and electron blocking layers.

[0057] Hole mobility μ H [cm 2 / [V·s]] can be determined by impedance spectroscopy as described in Japanese Patent Application Publication No. 2014-110348.

[0058] The electron transport region refers to the region where electrons move. The electron mobility μ within the electron transport region... E Preferably 10 - 6 cm 2 / [V·s] above.

[0059] The electron transmission region can be a single layer or multiple layers.

[0060] In addition to electron transport layers, other layers that constitute the electron transport region include electron injection layers and hole blocking layers.

[0061] electron mobility μ E [cm 2 / [V·s]] can be determined by impedance spectroscopy as described in Japanese Patent Application Publication No. 2014-110348.

[0062] The charge generation layer refers to the layer that injects holes into the light-emitting units disposed on the cathode side of the charge generation layer (in this embodiment, the first P layer 142 and the second P layer 162) and the layer that injects electrons into the light-emitting units disposed on the anode side of the charge generation layer (in this embodiment, the first N layer 141 and the second N layer 161).

[0063] The thickness d3 of the hole transport region (third hole transport region 171) of the third light-emitting unit 17 is 5 nm or more and 40 nm or less. From the viewpoint of further demonstrating the effect of this embodiment, the thickness of the third hole transport region 171 is preferably 10 nm or more and 30 nm or less, more preferably 15 nm or more and 25 nm or less, and even more preferably 15 nm or more and 20 nm or less.

[0064] If the thickness d3 of the third hole transport region 171 is greater than 5 nm, the extinction caused by the excessive proximity of the acceptor material contained in the second charge generation layer 16 to the third light-emitting layer 172 is suppressed.

[0065] If the thickness d3 of the third hole transport region 171 is less than 40 nm, the hole supply from the second charge generation layer 16 to the third light-emitting layer 172 is promoted, and the recombination region in the third light-emitting layer 172 is more likely to extend to the electron transport region side.

[0066] The thickness d3 of the third hole transmission region 171 refers to its total thickness when the third hole transmission region 171 is composed of multiple layers. The thicknesses of other regions (such as the first hole transmission region 131, etc.) and other layers (such as the third light-emitting layer, etc.) are the same.

[0067] The thickness d3 of the third hole transport region 171 was measured as follows.

[0068] The center part of organic EL element 1 ( Figure 1 The section (represented by the symbol CL) is cut along a direction perpendicular to the formation surface of the third hole transport region 171 (i.e., the thickness direction of the third hole transport region 171), and the cross-section at its center is observed and measured using a transmission electron microscope (TEM).

[0069] The thicknesses of other regions (e.g., the first hole transport region 131, the second hole transport region 151, etc.) and other layers (e.g., the second Nth layer 161, etc.) were also measured using the same method.

[0070] It should be noted that the center of the organic EL element 1 refers to the center of the shape obtained by projecting the organic EL element 1 from the cathode side. For example, when the projected shape is rectangular, it refers to the intersection of the diagonals of the rectangle.

[0071] From the viewpoint of further demonstrating the effect of this embodiment, the second hole transport region 151 is preferably connected to the first charge generation layer 14.

[0072] The thickness d2 of the second hole transport region 151 is preferably 5 nm or more and 40 nm or less, more preferably 10 nm or more and 30 nm or less, and even more preferably 15 nm or more and 25 nm or less.

[0073] From the viewpoint of further demonstrating the effect of this embodiment, the first hole transport region 131 is preferably connected to the anode 12.

[0074] The thickness of the first hole transport region 131 is preferably 5 nm or more and 40 nm or less, more preferably 10 nm or more and 30 nm or less, and even more preferably 15 nm or more and 25 nm or less.

[0075] From the viewpoint of further demonstrating the effect of this embodiment, the thickness of the N layer (second N layer 161) of the second charge generation layer 16 is preferably 40 nm or more, more preferably 45 nm or more, and even more preferably 50 nm or more.

[0076] From the viewpoint of obtaining the optical interference effect, the upper limit of the second N layer 161 is preferably 200 nm or less, more preferably 160 nm or less, and even more preferably 120 nm or less.

[0077] That is, the thickness of the N layer of the second charge generation layer 16 is preferably 40 nm or more and 200 nm or less, more preferably 45 nm or more and 160 nm or less, and even more preferably 50 nm or more and 120 nm or less.

[0078] From the viewpoint of further demonstrating the effect of this embodiment, the thickness d of the Nth layer (second Nth layer 161) of the second charge generation layer 16 N The ratio of the thickness d3 of the hole transport region (third hole transport region 171) of the third light-emitting unit 17 (thickness d) N The thickness d3 is preferably greater than 1 and less than 40, more preferably greater than 2 and less than 10, and even more preferably greater than 2.5 and less than 6.

[0079] In the organic EL element 1 of this embodiment, one of the anode 11 and the cathode 18 is a reflective electrode.

[0080] From the viewpoint of further inducing optical interference effect and further demonstrating the effect of this embodiment, the organic EL element 1 of this embodiment preferably satisfies the following mathematical formulas (1-3) and (2-3). As a result, the luminous efficiency of blue fluorescence emission can also be improved.

[0081] n³-0.25<m³<n³+0.25 (1-3)

[0082] In mathematical formula (1-3), n3 is an integer greater than or equal to 0, and m3 is the interference order between the reflective electrode and the luminescent center of the third luminescent layer. n3 is preferably an integer greater than or equal to 0 and less than or equal to 3.

[0083]

Mathematical Formula 1

[0084]

[0085] In mathematical formula (2-3), m3 has the same meaning as m3 in mathematical formula (1-3) above, L3 is the optical distance (nm) between the reflective electrode and the light emission center of the third light emission layer, λ3 is the main peak wavelength (nm) of the light emission from the third light emission layer, and Φ3 is the phase change when the light emission from the third light emission layer is reflected by the reflective electrode.

[0086] Furthermore, from the viewpoint of further inducing optical interference effect and further demonstrating the effect of this embodiment, the organic EL element 1 of this embodiment preferably satisfies the following mathematical formulas (1-2) and (2-2).

[0087] n²-0.25<m²<n²+0.25 (1-2)

[0088] In mathematical formula (1-2), n2 is an integer greater than or equal to 0, and m2 is the interference order between the reflective electrode and the light-emitting center of the second light-emitting layer. n2 is preferably an integer greater than or equal to 0 and less than or equal to 3.

[0089]

Mathematical Formula 2

[0090]

[0091] In mathematical formula (2-2), m2 has the same meaning as m2 in mathematical formula (1-2) above, L2 is the optical distance (nm) between the light emission centers of the reflective electrode and the second light emission layer, λ2 is the main peak wavelength (nm) of the light emission from the second light emission layer, and Φ2 is the phase change when the light emission from the second light emission layer is reflected by the reflective electrode.

[0092] Furthermore, from the viewpoint of further inducing optical interference effect and further demonstrating the effect of this embodiment, the organic EL element 1 of this embodiment preferably satisfies the following mathematical formula (1-1) and the following mathematical formula (2-1).

[0093] n1-0.25<m1<n1+0.25 (1-1)

[0094] In mathematical formula (1-1), n1 is an integer greater than or equal to 0, and m1 is the interference order between the reflective electrode and the light-emitting center of the first light-emitting layer. n1 is preferably an integer greater than or equal to 0 and less than or equal to 3.

[0095]

Mathematical Expression 3

[0096]

[0097] In mathematical formula (2-1), m1 has the same meaning as m1 in mathematical formula (1-1), L1 is the optical distance (nm) between the reflective electrode and the light emission center of the first light-emitting layer, λ1 is the main peak wavelength (nm) of the light emission from the first light-emitting layer, and Φ1 is the phase change when the light emission from the first light-emitting layer is reflected by the reflective electrode.

[0098] From the viewpoint of further inducing optical interference effects and further demonstrating the effects of this embodiment, the organic EL element 1 of this embodiment preferably satisfies the above mathematical formulas (1-3) and (2-3), or satisfies the above mathematical formulas (1-2) and (2-2), or satisfies the above mathematical formulas (1-3) and (2-3). Therefore, in addition to the effects of this embodiment, the luminous efficiency of blue fluorescence emission can also be improved.

[0099] From the viewpoint of further inducing optical interference effects and further demonstrating the effects of this embodiment, the organic EL element 1 of this embodiment is more preferably satisfied not only by satisfying the above mathematical formulas (1-3) and (2-3), but also by satisfying the above mathematical formulas (1-2) and (2-2); or not only by satisfying the above mathematical formulas (1-3) and (2-3), but also by satisfying the above mathematical formulas (1-1) and (2-1). Therefore, in addition to the effects of this embodiment, the luminous efficiency of blue fluorescence emission can be further improved.

[0100] From the viewpoint of further inducing optical interference effect and further demonstrating the effect of this embodiment, the organic EL element 1 of this embodiment is further preferably satisfied with all of the above mathematical formulas (1-1) to (1-3) and (2-1) to (2-3). As a result, in addition to the effect of this embodiment, the luminous efficiency of blue fluorescence emission can be further improved.

[0101] Here, for L1 to L3 (optical distance: nm) in mathematical formulas (2-1) to (2-3), refer to Figure 2 Please provide an explanation. Figure 2 In the middle, "d 10 "d" indicates the thickness of the first light-emitting layer 132. 20 "d" indicates the thickness of the second light-emitting layer 152. 30"" indicates the thickness of the third light-emitting layer 172.

[0102] Figure 2 This is a diagram illustrating the optical distance between the reflective electrode and the light-emitting center of each light-emitting layer for the organic EL element of the first embodiment.

[0103] For example, when the organic EL element 1 is a bottom-emitting type that extracts light from the anode 12 side and the cathode 18 is a reflective electrode, the optical distance L1 in mathematical formula (2-1) (equivalent to Figure 2 L in 1B ) refers to the reflective interface 18A of the cathode 18 (the surface of the cathode 18 on the first light-emitting layer side) and the light-emitting center of the first light-emitting layer 132. Figure 2 The optical distance between EC1 in the middle.

[0104] The light-emitting center of the first light-emitting layer 132 refers to the surface where the peak of the light-emitting intensity distribution in the thickness direction of the first light-emitting layer 132 is located.

[0105] In this specification, the light-emitting center of the first light-emitting layer 132 ( Figure 2 EC1 in the diagram is defined as the plane that bisects the thickness of the first light-emitting layer 132.

[0106] The optical distance L2 in mathematical formula (2-2) is equivalent to Figure 2 L in 2B The optical distance L3 in mathematical formula (2-3) is equivalent to Figure 2 L in 3B Furthermore, the light-emitting center of the second light-emitting layer 152 is equivalent to... Figure 2 In EC2, the luminescent center of the third luminescent layer 172 is equivalent to Figure 2 EC3 in the middle.

[0107] For example, when the organic EL element 1 is a top-emitting type that extracts light from the cathode 18 side and the anode 12 is a reflective electrode, the optical distance L1 in mathematical formula (2-1) (equivalent to Figure 2 L in 1T ) refers to the reflective interface 12A of the anode 12 (the surface of the anode 12 on the first light-emitting layer side) and the light-emitting center of the first light-emitting layer 132. Figure 2 The optical distance between EC1 in the middle.

[0108] The optical distance L2 in mathematical formula (2-2) is equivalent to Figure 2 L in 2T The optical distance L3 in mathematical formula (2-3) is equivalent to Figure 2 L in 3T .

[0109] The light-emitting center of the first light-emitting layer 132 is equivalent to Figure 2 In EC1, the luminescent center of the second luminescent layer 152 is equivalent to Figure 2 In EC2, the luminescent center of the third luminescent layer 172 is equivalent to Figure 2 EC3 in the middle.

[0110] (Luminous color)

[0111] In this specification, blue emission refers to emission within the range of wavelength of the main peak of the emission spectrum being above 430 nm and below 500 nm.

[0112] Yellow luminescence refers to luminescence with the main peak wavelength of the emission spectrum in the range of 530nm to 600nm.

[0113] Red emission refers to emission with the main peak wavelength of the emission spectrum in the range of 600nm to 660nm.

[0114] Green light emission refers to light emission with the main peak wavelength of the emission spectrum in the range of 500nm to 560nm.

[0115] In this specification, the "peak wavelength" as described as "the peak wavelength of light emitted from the third emitting layer" refers to the value obtained by measurement as follows.

[0116] The "peak wavelength" when expressed as "the peak wavelength of light emitted from the second emitting layer" and the "peak wavelength" when expressed as "the peak wavelength of light emitted from the first emitting layer" are the same.

[0117] The host material and dopant material contained in the light-emitting layer are co-deposited at the same ratio as the light-emitting layer in the light-emitting element, forming a film with a thickness of 50 nm on a quartz substrate. The emission spectrum obtained by photoexcitation is measured using a fluorescence spectrophotometer F-7000 (manufactured by Hitachi High-Tech Co., Ltd.). The wavelength of the peak wavelength where the emission intensity reaches the maximum in the obtained emission spectrum is taken as the main peak wavelength (unit: nm).

[0118] For the main peak wavelength when multiple light-emitting layers are stacked, each light-emitting layer is formed on a quartz substrate with a thickness of 50 nm in the same manner as the stacked light-emitting layers. The main peak wavelength is measured using the same method as described above with the aforementioned fluorescence spectrophotometer F-7000.

[0119] In the organic EL element 1 of this embodiment, the third light-emitting layer 172 is a blue fluorescent light-emitting layer containing a compound with blue fluorescent light-emitting properties.

[0120] The main peak wavelength of the emission from the third emitting layer is preferably above 430 nm and below 500 nm, more preferably above 440 nm and below 470 nm.

[0121] In the organic EL element 1 of this embodiment, the first light-emitting layer 132 is preferably a blue fluorescent light-emitting layer.

[0122] When the first light-emitting layer 132 is a blue fluorescent light-emitting layer, the main peak wavelength of the light emitted from the first light-emitting layer is preferably above 430nm and below 500nm, more preferably above 440nm and below 470nm.

[0123] The first light-emitting layer 132 can be a fluorescent light-emitting layer other than blue (e.g., yellow fluorescent light-emitting layer, red fluorescent light-emitting layer, and green fluorescent light-emitting layer), or it can be a phosphorescent light-emitting layer of various colors (e.g., blue phosphorescent light-emitting layer, yellow phosphorescent light-emitting layer, red phosphorescent light-emitting layer, and green phosphorescent light-emitting layer).

[0124] In the organic EL element 1 of this embodiment, the second light-emitting layer 152 is preferably a blue fluorescent light-emitting layer.

[0125] When the second light-emitting layer 152 is a blue fluorescent light-emitting layer, the main peak wavelength of the light emitted from the second light-emitting layer 152 is preferably 430 nm or more and 500 nm or less, more preferably 440 nm or more and 470 nm or less.

[0126] The second light-emitting layer 152 can be a fluorescent light-emitting layer other than blue (e.g., a yellow fluorescent light-emitting layer, a red fluorescent light-emitting layer, a green fluorescent light-emitting layer, and a fluorescent light-emitting layer formed by two or more of them), or a phosphorescent light-emitting layer of various colors (e.g., a blue phosphorescent light-emitting layer, a yellow phosphorescent light-emitting layer, a red phosphorescent light-emitting layer, a green phosphorescent light-emitting layer, and a phosphorescent light-emitting layer formed by two or more of them).

[0127] When the first luminescent layer 132 and the third luminescent layer 172 are blue fluorescent luminescent layers, or the second luminescent layer 152 and the third luminescent layer 172 are blue fluorescent luminescent layers, or the first luminescent layer 132, the second luminescent layer 152 and the third luminescent layer 172 are all blue fluorescent luminescent layers, the blue fluorescent luminescent compounds contained in each blue fluorescent luminescent layer can be the same or different from each other, and can contain one type of blue fluorescent luminescent compound or two or more types of blue fluorescent luminescent compounds.

[0128] The following schemes are preferred as schemes for each light-emitting layer.

[0129] • A scheme in which the first luminescent layer 132 is a yellow phosphorescent luminescent layer, the second luminescent layer 152 is a blue fluorescent luminescent layer, and the third luminescent layer 172 is a blue fluorescent luminescent layer.

[0130] • A scheme in which the first luminescent layer 132 is a blue fluorescent luminescent layer, the second luminescent layer 152 is a yellow phosphorescent luminescent layer, and the third luminescent layer 172 is a blue fluorescent luminescent layer.

[0131] • A scheme in which the first luminescent layer 132 is a red-yellow phosphorescent luminescent layer, the second luminescent layer 152 is a blue fluorescent luminescent layer, and the third luminescent layer 172 is a blue fluorescent luminescent layer.

[0132] • A scheme in which the first luminescent layer 132 is a blue fluorescent luminescent layer, the second luminescent layer 152 is a red-green phosphorescent luminescent layer, and the third luminescent layer 172 is a blue fluorescent luminescent layer.

[0133] • A scheme in which the first light-emitting layer 132, the second light-emitting layer 152 and the third light-emitting layer 172 are all blue fluorescent light-emitting layers.

[0134] Each light-emitting unit and each charge-generating layer will be described in detail. Symbols will be omitted below.

[0135] <First light-emitting unit, second light-emitting unit, and third light-emitting unit>

[0136] Each light-emitting unit contains its own light-emitting layer.

[0137] In the following description, when the first light-emitting layer, the second light-emitting layer, and the third light-emitting layer are not distinguished separately, they may sometimes be referred to simply as "light-emitting layer".

[0138] Each light-emitting layer can be a single light-emitting layer, or multiple light-emitting layers can be stacked together.

[0139] (Emitting layer)

[0140] The light-emitting layer preferably comprises a host material (sometimes called a matrix material) and a dopant material (sometimes called a light-emitting material, a guest material, or an emitter).

[0141] As the main material, well-known main materials can be used, such as amine derivatives, azazine derivatives, and fused polycyclic aromatic derivatives.

[0142] Examples of amine derivatives include monoamine compounds, diamine compounds, triamine compounds, tetraamine compounds, and amine compounds substituted with carbazole groups.

[0143] Examples of azine derivatives include monoazine derivatives, diazine derivatives, and triazine derivatives.

[0144] As fused polycyclic aromatic derivatives, fused polycyclic aromatic hydrocarbons without heterocyclic skeletons are preferred, such as naphthalene, anthracene, phenanthrene, etc. Fluoranthene and triphenylene, or their derivatives.

[0145] The main material is preferably a derivative of a fused polycyclic aromatic hydrocarbon, more preferably an anthracene derivative, and even more preferably an anthracene derivative as shown in the following general formula (11).

[0146]

Chemistry 1

[0147]

[0148] In the above general formula (11), R 101 ~R 110 Each can be an independent hydrogen atom or a substituent, with R acting as a substituent. 101 ~R 110 Each independently

[0149] Substituted or unsubstituted alkyl groups having 1 to 30 carbon atoms

[0150] Substituted or unsubstituted alkenyl groups with 2 to 30 carbon atoms

[0151] Substituted or unsubstituted alkynyl groups with 2 to 30 carbon atoms

[0152] Substituted or unsubstituted cycloalkyl groups with 3 to 30 carbon atoms

[0153] Substituted or unsubstituted alkoxy groups with 1 to 30 carbon atoms

[0154] Substituted or unsubstituted alkylthio groups with 1 to 50 carbon atoms

[0155] Substituted or unsubstituted aryloxy groups with 6 to 30 carbon atoms,

[0156] Substituted or unsubstituted arylthio groups with 6 to 30 carbon atoms

[0157] Substituted or unsubstituted aralkyl groups with 7 to 30 carbon atoms

[0158] -Si(R 121 (R) 122 (R) 123 ),

[0159] -C(=O)R 124 -COOR 125 ,

[0160] -N(R 126 (R) 127 ),

[0161] Halogen atoms,

[0162] cyano,

[0163] Nitro,

[0164] Substituted or unsubstituted aryl groups with 6 to 30 carbon atoms

[0165] Substituted or unsubstituted heterocyclic groups with 5 to 30 cyclic atoms, or

[0166] -L 101 -Ar 101 The group shown.

[0167] R 101 ~R 110 Two or more adjacent substituents (preferably two or more but less than three substituents) can bond together to form a saturated or unsaturated ring. The number of saturated or unsaturated rings formed is preferably one or more (preferably one or more but less than three). As a saturated or unsaturated ring, it is preferably a substituted or unsubstituted five-membered ring or a six-membered ring, more preferably a substituted or unsubstituted benzene ring.

[0168] In the above general formula (11), R 121 ~R 127 Each can be an independent hydrogen atom or a substituent, with R acting as a substituent. 121 ~R 127 Each independently

[0169] Substituted or unsubstituted alkyl groups having 1 to 30 carbon atoms

[0170] Substituted or unsubstituted aryl groups with 6 to 30 carbon atoms, or

[0171] A heterocyclic group with 5 to 30 cyclic atoms, either substituted or unsubstituted.

[0172] Among them, R 101 ~R 110 At least one of them is -L 101 -Ar 101 The group shown. L 101 L is a single bond or a linking group, and is used as a linking group. 101 Ar is a substituted or unsubstituted aryl group with 6 to 30 carbon atoms in a cyclic ring, or a substituted or unsubstituted heteroaryl group with 5 to 30 cyclic atoms in a cyclic ring. 101 It is an aryl group with 6 to 30 carbon atoms that is substituted or unsubstituted, or a heterocyclic group with 5 to 30 cyclic atoms that is substituted or unsubstituted.

[0173] L 101 When there are more than two, more than two L 101 They are the same or different. 101 When there are more than two, more than two Ar 101 They are the same or different. R 121 When there are more than two, more than two R 121 They are the same or different. R122 When there are more than two, more than two R 122 They are the same or different. R 123 When there are more than two, more than two R 123 They are the same or different. R 124 When there are more than two, more than two R 124 They are the same or different. R 125 When there are more than two, more than two R 125 They are the same or different. R 126 When there are more than two, more than two R 126 They are the same or different. R 127 When there are more than two, more than two R 127 They are the same or different.

[0174] In the above general formula (11), R 101 ~R 110 Each of the following is preferably an independent hydrogen atom, a substituted or unsubstituted alkyl group having 1 to 30 carbon atoms, a substituted or unsubstituted aryl group having 6 to 30 cyclic carbon atoms, a substituted or unsubstituted heterocyclic group having 5 to 30 cyclic atoms, or -L 101 -Ar 101 The indicated group is more preferably a hydrogen atom, a substituted or unsubstituted aryl group having 6 to 30 cyclic carbon atoms, a substituted or unsubstituted heterocyclic group having 5 to 30 cyclic atoms, or a -L group. 101 -Ar 101 The group shown.

[0175] In the above general formula (11), R 101 ~R 110 Among them, R 109 and R 110 Each is independently preferred to be -L 101 -Ar 101 The indicated group, more preferably R 109 and R 110 At least one of them is -L 101 -Ar 101 The group shown.

[0176] In the above general formula (11), it is preferred that R 101 ~R 110 At least one (preferably R) 109 and R 110 (at least one of them) is -L 101 -Ar 101 The group shown, -L 101 -Ar 101 Ar in the group shown 101 In the case of aryl, Ar 101It can be a substituted or unsubstituted phenyl group, or a substituted or unsubstituted naphthyl group.

[0177] In the above general formula (11), it is preferred that R 101 ~R 110 At least one (preferably R) 109 and R 110 (at least one of them) is -L 101 -Ar 101 The group shown, -L 101 -Ar 101 Ar in the group shown 101 In the case of a heterocyclic group, Ar 101 It can be a substituted or unsubstituted dibenzofuranyl, a substituted or unsubstituted dibenzothiophenyl, a substituted or unsubstituted naphthobenzofuranyl, or a substituted or unsubstituted naphthobenzothiophenyl.

[0178] Specific examples of compounds represented by the above general formula (11) are described below. The host material contained in the luminescent layer of the present invention is not limited to these specific examples.

[0179]

Chemistry 2

[0180]

[0181]

Transformation 3

[0182]

[0183] In this embodiment, when the first or second light-emitting layer is a phosphorescent light-emitting layer, the main material included in the phosphorescent light-emitting layer can be, for example, carbazole derivatives, triazole derivatives, oxazole derivatives, oxadiazole derivatives, imidazole derivatives, polyaryl alkane derivatives, pyrazoline derivatives, pyrazolineone derivatives, phenylenediamine derivatives, arylamine derivatives, amino-substituted chalcone derivatives, styrene-anthracene derivatives, fluorenone derivatives, hydrazone derivatives, styrene derivatives, silazane derivatives, aromatic tertiary amine compounds, styrene-anthracene compounds, aromatic dimethylidene compounds, porphyrin compounds, anthraquinone dimethane derivatives, anthrone derivatives, and diphenylene oxide. Benzoquinone derivatives, thiamethane dioxide derivatives, carbodiimide derivatives, fluorenemethane derivatives, stilbenepyrazine derivatives, and tetracarboxylic anhydrides (e.g., tetracarboxylic anhydrides of naphthylene), phthalocyanine derivatives, various metal complexes (e.g., metal complexes of 8-hydroxyquinoline derivatives, metal phthalocyanines, and metal complexes with benzoxazole or benzothiazole as ligands), polysilane compounds, conductive polymeric oligomers (e.g., poly(N-vinylcarbazole) derivatives, aniline copolymers, thiophene oligomers, and polythiophene), and polymeric compounds (e.g., polythiophene derivatives, polyphenylene derivatives, polystyrene derivatives, and polyfluorene derivatives), etc.

[0184] The main material can be used alone or in combination of two or more.

[0185] The light-emitting layer may contain only one type of main material or two or more types of main materials.

[0186] There is no particular limitation on the content of the main material. For example, the content of the main material relative to the entire light-emitting layer is preferably 80% by mass or more and 99.9% by mass or less, more preferably 90% by mass or more and 99.9% by mass or less, and even more preferably 95% by mass or more and 99.9% by mass or less.

[0187] • Dopant materials

[0188] The luminescent layer contains a dopant material. The dopant material is preferably a highly luminescent substance, and various materials can be used. For example, fluorescent materials that emit fluorescence and phosphorescent materials that emit phosphorescence can be used as dopant materials. Fluorescent materials are compounds capable of emitting light from a singlet excited state, while phosphorescent materials are compounds capable of emitting light from a triplet excited state.

[0189] In this embodiment, the blue fluorescent light-emitting layer (the third light-emitting layer and at least one of the first light-emitting layer and the second light-emitting layer) contains a blue fluorescent light-emitting compound (hereinafter also referred to as a blue fluorescent light-emitting material) as a dopant material.

[0190] It should be noted that the first or second luminescent layer can be a luminescent layer other than the blue fluorescent luminescent layer. In this case, it can contain fluorescent luminescent materials other than those in the blue color family, or it can contain phosphorescent luminescent materials of various colors.

[0191] As a blue fluorescent material, pyrene derivatives, styrene amine derivatives, etc. can be used. Derivatives, fluoranthene derivatives, fluorene derivatives, monoamine derivatives, diamine derivatives, and triarylamine derivatives, etc.

[0192] For red-based fluorescent materials, derivatives such as tetraphenylbenzene and diamine derivatives can be used. For green-based fluorescent materials, aromatic amine derivatives can be used. For yellow-based fluorescent materials, anthracene derivatives and fluoranthene derivatives can be used.

[0193] For blue phosphorescent materials, metal complexes such as iridium, osmium, and platinum complexes can be used. For green phosphorescent materials, iridium complexes can be used. For red phosphorescent materials, metal complexes such as iridium, platinum, terbium, and europium complexes can be used. For yellow phosphorescent materials, iridium complexes can be used.

[0194] The blue fluorescent material used in the blue fluorescent luminescent layer is preferably a monoamine derivative or a diamine derivative as shown in the following general formula (1).

[0195]

Chemistry 4

[0196]

[0197] In general formula (1), A represents

[0198] Substituted or unsubstituted aryl groups with 10 to 40 carbon atoms, or

[0199] Substituted or unsubstituted heteroaryl groups with 10 to 40 carbon atoms.

[0200] L1 and L2 are represented independently.

[0201] single bond,

[0202] Substituted or unsubstituted aryl groups with 6 to 12 carbon atoms, or

[0203] Substituted or unsubstituted heteroaryl groups with 5 to 12 carbon atoms in a cyclic structure.

[0204] Ar1 and Ar2 are represented independently.

[0205] Substituted or unsubstituted aryl groups with 6 to 25 carbon atoms, or

[0206] Substituted or unsubstituted heteroaryl groups with 3 to 25 carbon atoms.

[0207] n is 1 or 2.

[0208] As an example of a substituent when it has a substituent, it represents

[0209] Substituted or unsubstituted alkyl groups having 1 to 20 carbon atoms

[0210] Substituted or unsubstituted aryl groups with 6 to 25 carbon atoms

[0211] Substituted or unsubstituted aryl groups with 7 to 25 carbon atoms

[0212] Substituted or unsubstituted cycloalkyl groups with 3 to 25 carbon atoms

[0213] Substituted or unsubstituted alkoxy groups with 3 to 20 carbon atoms

[0214] Substituted or unsubstituted aryloxy groups with 6 to 25 carbon atoms,

[0215] Substituted or unsubstituted arylamino groups with 6 to 20 carbon atoms,

[0216] Fluorine atom,

[0217] Substituted or unsubstituted alkylamino groups having 1 to 20 carbon atoms, or

[0218] Cyano group.

[0219] Specific examples of the monoamine derivatives and diamine derivatives shown in the above general formula (1) are described below. The dopant material (blue fluorescent material) used in the blue fluorescent emitting layer is not limited to these specific examples.

[0220]

Transformation 5

[0221]

[0222] The dopant material (blue fluorescent material) used in the blue fluorescent emitting layer is preferably a compound represented by the following general formula (D2).

[0223]

Transformation 6

[0224]

[0225] In the above general formula (D2), rings α, β, and γ are each independently chosen.

[0226] Substituted or unsubstituted aromatic hydrocarbon rings with 6 to 30 carbon atoms, and

[0227] The group consisting of aromatic heterocycles with 5 to 30 cyclic atoms, either substituted or unsubstituted.

[0228] R a and R b Each independently chooses freedom

[0229] Substituted or unsubstituted aryl groups with 6 to 30 carbon atoms

[0230] Substituted or unsubstituted heteroaryl groups with 5 to 30 cyclic atoms, and

[0231] The group consisting of substituted or unsubstituted alkyl groups having 1 to 20 carbon atoms.

[0232] R a It can be bonded directly or via a linking group to one or both of the α and β rings.

[0233] R b It can be bonded directly or via a linking group to one or both of the α and γ rings.

[0234] In the above general formula (D2), the number of carbon atoms in the aromatic hydrocarbon ring is preferably 6 to 24, more preferably 6 to 18.

[0235] Examples of aromatic hydrocarbon rings mentioned above include: benzene rings, biphenyl rings, naphthyl rings, terphenyl rings (m-terphenyl rings, ortho-terphenyl rings, para-terphenyl rings), anthracene rings, acenaphthene rings, fluorene rings, finasterene rings, phenanthrene rings, triphenylene rings, fluoranthene rings, pyrene rings, tetraphenylene rings, perylene rings, and pentaphenyl rings.

[0236] In the above general formula (D2), the number of cyclic atoms of the aromatic heterocycle is preferably 5 to 18, more preferably 5 to 13.

[0237] The aforementioned aromatic heterocycle contains at least one (preferably one to five) cyclic heteroatoms. These cyclic heteroatoms are, for example, selected from nitrogen, sulfur, and oxygen atoms.

[0238] Examples of aromatic heterocycles mentioned above include: pyrrole ring, oxazole ring, isoxazole ring, thiazole ring, isothiazole ring, imidazole ring, oxadiazole ring, thiadiazole ring, triazole ring, tetraazole ring, pyrazole ring, pyridine ring, pyrimidine ring, pyrazine ring, pyrazine ring, triazine ring, indole ring, isoindole ring, 1H-indazole ring, benzimidazole ring, benzoxazole ring, benzothiazole ring, 1H-benzotriazole ring, quinoline ring, and isoquinoline ring. Phosphorus ring, cyclophosphine ring, quinazoline ring, quinoxaline ring, phthalazine ring, naphthidine ring, purine ring, pteridine ring, carbazole ring, acridine ring, phenoxathiin ring, phenoxazine ring, phenthiazine ring, phenazine ring, indazine ring, furan ring, benzofuran ring, isobenzofuran ring, dibenzofuran ring, thiophene ring, benzothiophene ring, dibenzothiophene ring, furazine ring, oxadiazole ring, and thiathracene ring, etc.

[0239] In the above general formula (D2), ring α, ring β, and ring γ are each preferably a five-membered ring or a six-membered ring.

[0240] In the above general formula (D2), when the rings α, β, and γ are expressed as "substituted or unsubstituted", the substituents D are each preferably selected independently.

[0241] Substituted or unsubstituted aryl groups with 6 to 30 carbon atoms

[0242] Substituted or unsubstituted heteroaryl groups with 5 to 30 cyclic atoms

[0243] A diarylamino, diheteroarylamino, or arylheteroarylamino formed by substitution of at least one group selected from the group consisting of a substituted or unsubstituted aryl group having 6 to 30 carbon atoms and a substituted or unsubstituted heteroaryl group having 5 to 30 carbon atoms.

[0244] Substituted or unsubstituted alkyl groups having 1 to 20 carbon atoms

[0245] Substituted or unsubstituted alkoxy groups having 1 to 20 carbon atoms, and

[0246] A group consisting of at least one of the group consisting of substituted or unsubstituted aryloxy groups having 6 to 30 carbon atoms.

[0247] In the above general formula (D2), when the rings α, β, and γ are expressed as "substituted or unsubstituted", the substituent D is more preferably selected independently.

[0248] Substituted or unsubstituted aryl groups with 6 to 24 carbon atoms

[0249] Substituted or unsubstituted heteroaryl groups with 5 to 18 cyclic atoms

[0250] A diarylamino, diheteroarylamino, or arylheteroarylamino formed by substitution of at least one group selected from the group consisting of a substituted or unsubstituted aryl group having 6 to 24 carbon atoms and a substituted or unsubstituted heteroaryl group having 5 to 18 cyclic atoms.

[0251] Substituted or unsubstituted alkyl groups having 1 to 10 carbon atoms

[0252] Substituted or unsubstituted alkoxy groups having 1 to 10 carbon atoms, and

[0253] At least one group from the group consisting of substituted or unsubstituted aryloxy groups having 6 to 24 carbon atoms.

[0254] In the above general formula (D2), when the rings α, β, and γ are expressed as "substituted or unsubstituted", the substituents D are each independently and further preferably selected from...

[0255] Substituted or unsubstituted aryl groups with 6 to 18 carbon atoms

[0256] Substituted or unsubstituted heteroaryl groups with 5 to 13 cyclic atoms

[0257] A diarylamino, diheteroarylamino, or arylheteroarylamino formed by substitution of at least one group selected from the group consisting of a substituted or unsubstituted aryl group having 6 to 18 carbon atoms and a substituted or unsubstituted heteroaryl group having 5 to 13 cyclic atoms.

[0258] Substituted or unsubstituted alkyl groups having 1 to 6 carbon atoms

[0259] Substituted or unsubstituted alkoxy groups having 1 to 6 carbon atoms, and

[0260] At least one group from the group consisting of substituted or unsubstituted aryloxy groups having 6 to 18 carbon atoms.

[0261] When the substituent D further has substituent E, each substituent E is preferably independently selected.

[0262] Substituted or unsubstituted aryl groups with 6 to 30 carbon atoms

[0263] Substituted or unsubstituted heteroaryl groups with 5 to 30 cyclic atoms, and

[0264] At least one group from the group consisting of substituted or unsubstituted alkyl groups having 1 to 20 carbon atoms.

[0265] When the substituent D further has a substituent E, each substituent E is more preferably selected independently.

[0266] Substituted or unsubstituted aryl groups with 6 to 24 carbon atoms

[0267] Substituted or unsubstituted heteroaryl groups with 5 to 18 cyclic atoms, and

[0268] At least one group from the group consisting of substituted or unsubstituted alkyl groups having 1 to 10 carbon atoms.

[0269] When the substituent D further has substituent E, each substituent E is further preferably selected independently.

[0270] Substituted or unsubstituted aryl groups with 6 to 18 carbon atoms

[0271] Substituted or unsubstituted heteroaryl groups with 5 to 13 cyclic atoms, and

[0272] At least one group from the group consisting of substituted or unsubstituted alkyl groups having 1 to 6 carbon atoms.

[0273] In the above general formula (D2), two adjacent substituents on ring α, ring β, and ring γ can bond together to form an aromatic hydrocarbon ring with 6 to 30 substituted or unsubstituted carbon atoms, or an aromatic heterocycle with 5 to 30 substituted or unsubstituted carbon atoms.

[0274] In the above general formula (D2), when two adjacent substituents on ring α, ring β, and ring γ bond to each other to form a ring, the ring is preferably an aromatic hydrocarbon ring with 6 to 24 substituted or unsubstituted carbon atoms, or an aromatic heterocycle with 5 to 18 substituted or unsubstituted carbon atoms.

[0275] In the above general formula (D2), when two adjacent substituents D on ring α, ring β, and ring γ are bonded together to form a ring, the ring is more preferably […].

[0276] Substituted or unsubstituted aromatic hydrocarbon rings with 6 to 18 carbon atoms, or

[0277] Aromatic heterocycles with 5 to 13 cyclic atoms, substituted or unsubstituted.

[0278] In the above general formula (D2), the substituent F of the ring, which is formed when two adjacent substituents D on ring α, ring β, and ring γ are bonded together, can be the same group as the substituent E mentioned above, and the preferred range is also the same.

[0279] In the above general formula (D2), R a and R b Each independently selects the best option.

[0280] Substituted or unsubstituted aryl groups with 6 to 24 carbon atoms

[0281] Substituted or unsubstituted heteroaryl groups with 5 to 18 cyclic atoms, and

[0282] At least one group from the group consisting of substituted or unsubstituted alkyl groups having 1 to 10 carbon atoms.

[0283] In the above general formula (D2), R a and R b Each independently is better for the freedom of choice

[0284] Substituted or unsubstituted aryl groups with 6 to 18 carbon atoms

[0285] Substituted or unsubstituted heteroaryl groups with 5 to 13 cyclic atoms, and

[0286] At least one group from the group consisting of substituted or unsubstituted alkyl groups having 1 to 6 carbon atoms.

[0287] In general formula (D2), the above-mentioned linking group is

[0288] -O-, -S-, or -CR c R d -,

[0289] R c and R d Each independently

[0290] hydrogen atom, or

[0291] Alkyl groups with 1 to 20 carbon atoms, substituted or unsubstituted.

[0292] The substituted or unsubstituted alkyl group having 1 to 20 carbon atoms preferably has 1 to 10 carbon atoms, more preferably 1 to 6 carbon atoms.

[0293] As specific examples of the substituents in the general formula (D2), the groups described in the "Explanation of Substituents" section below can be cited.

[0294] As for "substituted or unsubstituted aromatic hydrocarbon rings with 6 to 30 carbon atoms" in general formula (D2), in addition to the aromatic hydrocarbon rings listed above, aromatic hydrocarbon rings described in the "Explanation of Substituents" below may also be used.

[0295] As for "aromatic heterocycle with 5 to 30 cyclic atoms, substituted or unsubstituted" in the general formula (D2), in addition to the aromatic heterocycles listed above, aromatic heterocycles described in the "Explanation of Substituents" below may also be used.

[0296] The dopant material (blue fluorescent material) used in the blue fluorescent emitting layer is preferably a compound represented by the following general formula (D3).

[0297]

Transformation 7

[0298]

[0299] In the general formula (D3),

[0300] R 11 ~R 20 and R a1 ~R a10 Each is independently a hydrogen atom or a substituent, wherein R 11 and R 12 group, R 12 and R 13 group, R 13 and R 14 group, R 14 and R 15 group, R 15 and R 16 group, R 17 and R 18 Group, R 18 and R 19 group, R 19 and R 20 group, R a1 and R a2 group, R a2 and R a3 group, R a3 and R a4 group, R a4 and R a5 R a6 and R a7 group, R a7 and R a8 group, R a8 and R a9 The group, and R a9 and R a10 One or more groups can bond together to form a saturated or unsaturated ring with 3 to 30 substituted or unsubstituted cyclic atoms.

[0301] R as a substituent 11 ~R 20 and R a1 ~Ra10 Each independently chooses freedom

[0302] Substituted or unsubstituted alkyl groups having 1 to 30 carbon atoms

[0303] Substituted or unsubstituted cycloalkyl groups with 3 to 30 carbon atoms

[0304] Substituted or unsubstituted alkoxy groups with 1 to 30 carbon atoms

[0305] Substituted or unsubstituted alkylthio groups with 1 to 30 carbon atoms

[0306] Substituted or unsubstituted amino groups

[0307] Substituted or unsubstituted aryl groups with 6 to 30 carbon atoms

[0308] Substituted or unsubstituted heterocyclic groups with 5 to 30 cyclic atoms

[0309] Substituted or unsubstituted alkenyl groups with 2 to 30 carbon atoms

[0310] Substituted or unsubstituted aryloxy groups with 6 to 30 carbon atoms,

[0311] Substituted or unsubstituted arylthio groups with 6 to 30 carbon atoms

[0312] Substituted or unsubstituted phosphine groups

[0313] Substituted or unsubstituted phosphoryl groups

[0314] Substituted or unsubstituted silyl groups

[0315] Substituted or unsubstituted aryl carbonyl groups with 6 to 30 carbon atoms,

[0316] cyano,

[0317] Nitro,

[0318] Carboxyl group, and

[0319] A group composed of halogen atoms.

[0320] For "R" in general formula (D3) 11 and R 12 group, R 12 and R 13 group, R 13 and R 14 group, R 14 and R 15 group, R 15 and R 16 group, R 17 and R 18 Group, R 18 and R 19 group, R19 and R 20 group, R a1 and R a2 group, R a2 and R a3 group, R a3 and R a4 group, R a4 and R a5 R a6 and R a7 group, R a7 and R a8 group, R a8 and R a9 The group, and R a9 and R a10 The specific examples of saturated or unsaturated rings formed by the mutual bonding of any one or more groups in the above are explained.

[0321] In general formula (D3), if R 17 ~R 20 For example, a local structure can be illustrated by the following general formula (D3-1). In the following local structure, adjacent R... 18 R 19 and R 20 These three bonds together form a ring. It should be noted that, according to R... 18 R 19 and R 20 The types of substituents are as follows: the local structure shown in the general formula (D3-1) below can have local structures. * indicates a bonding site.

[0322]

Transformation 8

[0323]

[0324] In addition, in general formula (D3), if R is used... 11 ~R 16 For example, a local structure can be exemplified by the following general formula (D3-2). In the following local structure, R 12 and R 13 and R 14 and R 15 These two groups bond together to form two rings. It should be noted that, according to R... 12 R 13 R 14 and R 15 The types of substituents are as follows: the local structure shown in the general formula (D3-2) below can have local structures. * indicates a bonding site.

[0325]

Chemistry 9

[0326]

[0327] In one embodiment, as a way to form the above-mentioned ring, R in general formula (D3) can also be cited. 12 and R 13 Schemes that form saturated or unsaturated rings with 3 to 30 substituted or unsubstituted cyclic atoms by mutual bonding (hereinafter also referred to as Scheme A).

[0328] The local structure is not limited to the local structures shown in general formulas (D3-1) to (D3-2). Furthermore, the scheme for forming the aforementioned ring is not limited to scheme A.

[0329] The light-emitting layer may contain only one type of dopant material or more than two types.

[0330] There is no particular limitation on the content of the dopant material. For example, the content of the dopant material relative to the entire light-emitting layer is preferably 0.1% by mass or more and 20% by mass or less, more preferably 0.1% by mass or more and 10% by mass or less, and even more preferably 0.1% by mass or more and 5% by mass or less.

[0331] The thickness of the first light-emitting layer (or its total thickness when there are multiple layers) is preferably 5 nm or more and 100 nm or less, more preferably 10 nm or more and 80 nm or less, and even more preferably 15 nm or more and 60 nm or less.

[0332] The thickness of the second light-emitting layer (or its total thickness when there are multiple layers) is preferably 5 nm or more and 100 nm or less, more preferably 10 nm or more and 80 nm or less, and even more preferably 15 nm or more and 60 nm or less.

[0333] The thickness of the third light-emitting layer (or its total thickness when there are multiple layers) is preferably 5 nm or more and 100 nm or less, more preferably 10 nm or more and 80 nm or less, and even more preferably 15 nm or more and 60 nm or less.

[0334] The thicknesses of the first, second, and third light-emitting layers can be the same or different.

[0335] (hole transport region)

[0336] In each light-emitting unit, in addition to the hole transport layer, other layers that constitute the hole transport region include, for example, the hole injection layer and the electron blocking layer.

[0337] Hole transport layer

[0338] The hole transport layer contains materials with high hole transport properties (preferably a hole mobility of 10). -6 cm 2A hole transport layer of [V·s] or higher can be used. Aromatic amine compounds, carbazole derivatives, and anthracene derivatives can be used. Specifically, the hole transport layer can use 4,4'-bis[N-(1-naphthyl)-N-phenylamino]biphenyl (NPB), N,N'-bis(3-methylphenyl)-N,N'-diphenyl-[1,1'-biphenyl]-4,4'-diamine (TPD), 4-phenyl-4'-(9-phenylfluorene-9-yl)triphenylamine (BAFLP), 4,4'-bis[N-(9,9-dimethylfluorene-2-yl]... Aromatic amine compounds such as [-N-phenylamino]biphenyl (abbreviated as DFLDPBi), 4,4',4”-tris(N,N-diphenylamino)triphenylamine (abbreviated as TDATA), 4,4',4”-tris[N-(3-methylphenyl)-N-phenylamino]triphenylamine (abbreviated as MTDATA), and 4,4'-bis[N-(spiro-9,9'-difluorene-2-yl)-N-phenylamino]biphenyl (abbreviated as BSPB).

[0339] Carbazole derivatives such as CBP, CzPA, and PCzPA, and anthracene derivatives such as t-BuDNA, DNA, and DPANth can also be used in the hole transport layer. Polymer compounds such as poly(N-vinylcarbazole) (PVK) and poly(4-vinyltriphenylamine) (PVTPA) can also be used.

[0340] Of these, any substance whose hole transport capability is higher than its electron transport capability can use these other substances. It should be noted that the layer containing the substance with high hole transport capability can be a single layer or a layer composed of two or more layers formed by stacking the aforementioned substances.

[0341] Hole injection layer

[0342] A hole injection layer is a layer containing a material with high hole injection capability. Materials with high hole injection capability can include molybdenum oxide, titanium oxide, vanadium oxide, rhenium oxide, ruthenium oxide, chromium oxide, zirconium oxide, hafnium oxide, tantalum oxide, silver oxide, tungsten oxide, and manganese oxide, among others.

[0343] Examples of substances with high hole-injection potential include 4,4',4"-tris(N,N-diphenylamino)triphenylamine (TDATA), 4,4',4"-tris[N-(3-methylphenyl)-N-phenylamino]triphenylamine (MTDATA), 4,4'-bis[N-(4-diphenylaminophenyl)-N-phenylamino]biphenyl (DPAB), and 4,4'-bis(N-{4-[N'-(3-methylphenyl)-N'-phenylamino]phenyl}-N-phenylamino)biphenyl (DN). Aromatic amine compounds such as TPD, 1,3,5-tris[N-(4-diphenylaminophenyl)-N-phenylamino]benzene (abbreviation: DPA3B), 3-[N-(9-phenylcarbazole-3-yl)-N-phenylamino]-9-phenylcarbazole (abbreviation: PCzPCA1), 3,6-bis[N-(9-phenylcarbazole-3-yl)-N-phenylamino]-9-phenylcarbazole (abbreviation: PCzPCA2), and 3-[N-(1-naphthyl)-N-(9-phenylcarbazole-3-yl)amino]-9-phenylcarbazole (abbreviation: PCzPCN1).

[0344] As substances with high hole-injection potential, polymeric compounds (oligomers, dendritic polymers, polymers, etc.) can also be used. Examples include poly(N-vinylcarbazole) (PVK), poly(4-vinyltriphenylamine) (PVTPA), poly[N-(4-{N'-[4-(4-diphenylamino)phenyl]phenyl-N'-phenylamino}phenyl)methacrylamide] (PTPDMA), and poly[N,N'-bis(4-butylphenyl)-N,N'-bis(phenyl)benzidine] (Poly-TPD). Additionally, acid-containing polymeric compounds such as poly(3,4-ethylenedioxythiophene) / poly(styrenesulfonic acid) (PEDOT / PSS) and polyaniline / poly(styrenesulfonic acid) (PAni / PSS) can also be used.

[0345] (Electronic transmission area)

[0346] In each light-emitting unit, in addition to the electron transport layer, other layers that constitute the electron transport region include, for example, the electron injection layer and the hole blocking layer.

[0347] Electron transport layer

[0348] The electron transport layer contains a material with high electron transport properties (preferably an electron mobility of 10). -6 cm 2The electron transport layer can be composed of: 1) metal complexes such as aluminum complexes, beryllium complexes, and zinc complexes; 2) heteroaromatic compounds such as imidazole derivatives, benzimidazole derivatives, azazine derivatives, carbazole derivatives, and phenanthroline derivatives; and 3) high molecular weight compounds. Specifically, as low molecular weight organic compounds, metal complexes such as Alq, tris(4-methyl-8-hydroxyquinoline)aluminum (abbreviated as Almq3), bis(10-hydroxybenzo[h]quinoline)beryllium (abbreviated as BeBq2), BAlq, Znq, ZnPBO, and ZnBTZ can be used. In addition to metal complexes, heteroaromatic compounds such as 2-(4-biphenyl)-5-(4-tert-butylphenyl)-1,3,4-oxadiazole (abbreviated as PBD), 1,3-bis[5-(p-tert-butylphenyl)-1,3,4-oxadiazole-2-yl]benzene (abbreviated as OXD-7), 3-(4-tert-butylphenyl)-4-phenyl-5-(4-biphenyl)-1,2,4-triazole (abbreviated as TAZ), 3-(4-tert-butylphenyl)-4-(4-ethylphenyl)-5-(4-biphenyl)-1,2,4-triazole (abbreviated as p-EtTAZ), phenanthroline (abbreviated as BPhen), copper bath (abbreviated as BCP), and 4,4'-bis(5-methylbenzoxazol-2-yl)zirconia (abbreviated as BzOs) can also be used. It should be noted that any material whose electron transport properties are higher than its hole transport properties can be used as an electron transport layer, regardless of the materials mentioned above. Furthermore, the electron transport layer can be a single layer or a layer composed of two or more layers of the aforementioned materials stacked together.

[0349] Alternatively, polymeric compounds can be used in the electron transport layer. For example, poly[(9,9-dihexylfluorene-2,7-diyl)-co-(pyridine-3,5-diyl)] (abbreviated as PF-Py) and poly[(9,9-dioctylfluorene-2,7-diyl)-co-(2,2'-bipyridine-6,6'-diyl)] (abbreviated as PF-BPy) can be used.

[0350] • Electron injection layer

[0351] The electron injection layer is a layer containing a material with high electron injection capability. Electron injection layers can use lithium (Li), cesium (Cs), calcium (Ca), lithium fluoride (LiF), cesium fluoride (CsF), calcium fluoride (CaF2), and lithium oxide (LiO). x Alkali metals, alkaline earth metals, or their compounds can be used. Alternatively, the electron injection layer can contain alkali metals, alkaline earth metals, or their compounds; specifically, materials containing magnesium (Mg) in Alq can be used. It should be noted that this allows for more efficient self-cathode electron injection.

[0352] Alternatively, a composite material consisting of a mixed organic compound and an electron donor can be used for the electron injection layer. Such a composite material generates electrons in the organic compound due to the electron donor, thus exhibiting excellent electron injection and electron transport properties. In this case, the organic compound is preferably a material with excellent electron transport properties; specifically, substances constituting the electron transport layer as described above (metal complexes, heteroaromatic compounds, etc.) can be used. The electron donor can be any substance that exhibits electron-donating properties to the organic compound. Specifically, alkali metals, alkaline earth metals, and rare earth metals are preferred as electron donors, including lithium, cesium, magnesium, calcium, erbium, and ytterbium. Additionally, alkali metal oxides and alkaline earth metal oxides are preferred as electron donors, including lithium oxides, calcium oxides, and barium oxides. Lewis bases such as magnesium oxide can also be used. Furthermore, organic compounds such as tetrathiofulvalene (TTF) can also be used.

[0353] When the first light-emitting unit has a first electron transport region, the thickness of the first electron transport region (referring to its total thickness when it is formed by multiple layers) is preferably 0 nm or more and 200 nm or less, more preferably 0 nm or more and 150 nm or less, even more preferably 0 nm or more and 100 nm or less, and even more preferably 5 nm or more and 100 nm or less.

[0354] When the second light-emitting unit has a second electron transport region, the thickness of the second electron transport region (referring to its total thickness when it is formed by multiple layers) is preferably 0 nm or more and 200 nm or less, more preferably 0 nm or more and 150 nm or less, even more preferably 0 nm or more and 100 nm or less, and even more preferably 5 nm or more and 100 nm or less.

[0355] When the third light-emitting unit has a third electron transport region, the thickness of the third electron transport region (referring to its total thickness when it is formed by multiple layers) is preferably 0 nm or more and 200 nm or less, more preferably 0 nm or more and 150 nm or less, even more preferably 0 nm or more and 100 nm or less, and even more preferably 5 nm or more and 100 nm or less.

[0356] (First charge generation layer, second charge generation layer)

[0357] The first charge-generating layer comprises a first N layer located on the anode side and a first P layer located on the cathode side.

[0358] The second charge-generating layer comprises a second N layer located on the anode side and a second P layer located on the cathode side.

[0359] It should be noted that the first charge generation layer may have other layers (such as organic layers, metal layers, and metal oxide layers) between the first N layer and the first P layer. Similarly, the second charge generation layer may also have the aforementioned other layers between the second N layer and the second P layer.

[0360] ·N layers

[0361] The N-layer preferably comprises π-deficient compounds and electron-donating materials.

[0362] · π-electron-deficient compounds

[0363] Examples of π-electron-deficient compounds include those that can coordinate with metal atoms. Specifically, examples include phenanthrene-rholine compounds, benzimidazole compounds, and hydroxyquinoline compounds.

[0364] As phenanthroline compounds, compounds represented by formulas (I') to (III') are preferred. Among them, compounds represented by formulas (I') or (II') are preferred.

[0365]

Chemistry 10

[0366]

[0367] In the above equations (I') to (III'), R 1a ~R 7a R 1b ~R 7b and R 1c ~R 6c Each independently constitutes a hydrogen atom,

[0368] Substituted or unsubstituted aryl groups with 6 to 30 carbon atoms

[0369] Substituted or unsubstituted pyridinyl groups

[0370] Substituted or unsubstituted quinolinyl group

[0371] Substituted or unsubstituted alkyl groups having 1 to 30 carbon atoms

[0372] Substituted or unsubstituted cycloalkyl groups with 3 to 30 carbon atoms

[0373] Substituted or unsubstituted aralkyl groups with 7 to 30 carbon atoms

[0374] Substituted or unsubstituted alkoxy groups with 1 to 30 carbon atoms

[0375] Substituted or unsubstituted aryloxy groups with 6 to 30 carbon atoms,

[0376] Substituted or unsubstituted arylthio groups with 6 to 30 carbon atoms

[0377] Substituted or unsubstituted alkoxycarbonyl groups with 2 to 30 carbon atoms

[0378] Substituted or unsubstituted aryl-substituted amino groups with 6-30 carbon atoms

[0379] Halogen atoms,

[0380] cyano,

[0381] Nitro,

[0382] hydroxyl, or

[0383] carboxyl.

[0384] R 1a ~R 7a R 1b ~R 7b Or R 1c ~R 6c In this process, adjacent groups can bond with each other to form a ring. Examples of rings include benzene rings, naphthalene rings, pyrazine rings, pyridine rings, and furan rings.

[0385] L 1a and L 1b Each can be an independent single bond or a linking group. L acts as a linking group. 1a and L 1b Examples of substituted or unsubstituted aromatic groups having 6 to 20 carbon atoms, substituted or unsubstituted alkylene chains having 1 to 8 carbon atoms, and substituted or unsubstituted heterocycles can be independently cited. Specifically, substituted or unsubstituted benzene rings, substituted or unsubstituted naphthalene rings, substituted or unsubstituted methylene chains, or substituted or unsubstituted pyridine rings are preferred.

[0386] Ar 1a Ar 1b Ar 1c and Ar 2c Each is an aromatic group, either substituted or unsubstituted, consisting of 6 to 30 cyclic carbons.

[0387] When n is 1 to 4, and n is 2 or more, the groups with the phenanthroline skeleton inside the parentheses can be the same or different.

[0388] The following are specific examples of compounds represented by formulas (I') to (III').

[0389]

Chemistry 11

[0390]

[0391] · Electronic materials

[0392] Examples of electron-donating materials include elemental metals, metal compounds, and metal complexes. Specifically, a layer containing at least one of the following is preferred: alkali metal, alkali metal compound, organometallic complex containing alkali metal, alkaline earth metal, alkaline earth metal compound, organometallic complex containing alkaline earth metal, rare earth metal, rare earth metal compound, and organometallic complex containing rare earth metal. Preferably, a layer containing at least one of the following is preferred: elemental alkali metal, alkaline earth metal, rare earth metal, rare earth metal compound, and rare earth metal complex.

[0393] P layer

[0394] A P-layer is a layer containing acceptor material. A P-layer can also be a layer doped with acceptor material (P-doped layer).

[0395] When the acceptor material is an organic material, examples of acceptor materials include: compounds represented by the following general formula (I) (indenefluorene dione derivatives) and compounds represented by the following general formula (III).

[0396] When the acceptor material is an inorganic material, examples of acceptor materials include molybdenum oxide (MoO3), vanadium oxide (V2O5), and transparent oxides (such as ITO and IZO).

[0397] Alternatively, acceptor materials can be appropriately selected from the "substances with high hole-injectability" exemplified in the above-mentioned hole injection layer projects.

[0398] It should be noted that the first hole transport region, the second hole transport region, and the third hole transport region refer to regions that do not contain the recipient material.

[0399] As the acceptor material used in the P layer, for example, a compound (indofluorene dione derivative) represented by the following general formula (I) can be used.

[0400]

Chemistry 12

[0401]

[0402] In general formula (I), Ar 1 It is an aromatic ring with 6 to 24 carbon atoms or a heterocyclic ring with 5 to 24 atoms, preferably an aromatic ring with 6 to 14 carbon atoms or a heterocyclic ring with 5 to 14 atoms. Examples of aromatic rings include benzene rings, naphthyl rings, fluorene rings, 9,9-dimethylfluorene rings, and 9,9-dioctylfluorene rings. Examples of heterocyclic rings include pyrazine rings, pyridine rings, quinoxaline rings, thiophene rings, benzothiophene rings, dibenzothiophene rings, furan rings, benzofuran rings, dibenzofuran rings, phenanthroline rings, naphthidine rings, and tetrazine anthracene rings.

[0403] The aforementioned aromatic rings and heterocycles can be represented by the following R...1 ~R 4 What it replaced.

[0404] It should be noted that "nuclear carbon" refers to the carbon atom that makes up the aromatic ring, while "nuclear atom" refers to the carbon atom and heteroatom that make up the heterocycle (including saturated rings, unsaturated rings, and aromatic heterocycles).

[0405] Rg 1 and Rg 2 Each can be the same or different from the others, as shown in the following general formula (i) or general formula (ii).

[0406]

Chemistry 13

[0407]

[0408] In general formulas (i) and (ii), X 1 and X 2 They can be the same or different, and can be any of the divalent groups shown in the following general formulas (a) to (g).

[0409]

Chemistry 14

[0410]

[0411] In the above general formulas (a) to (g), R 21 ~R 24 Each can be the same or different from the others, and can be a hydrogen atom, a substituted or unsubstituted fluoroalkyl group, a substituted or unsubstituted alkyl group, a substituted or unsubstituted aryl group, or a substituted or unsubstituted heterocyclic group, R 22 and R 23 They can bond together to form a ring.

[0412] Y 1 ~Y 4 They can be the same or different, and can be -N=, -CH=, or C(R) 5 ) =, R 5 With R as described later 1 ~R 4 They have the same meaning. R 1 ~R 5 Adjacent groups can bond with each other to form a ring.

[0413] In general formula (I), R 1 ~R 4Each of these can be the same or different from the others, and can be a hydrogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted cycloalkyl group, a substituted or unsubstituted alkenyl group, a substituted or unsubstituted aryl group, a substituted or unsubstituted heterocyclic group, a halogen atom, a substituted or unsubstituted fluoroalkyl group, a substituted or unsubstituted alkoxy group, a substituted or unsubstituted fluoroalkoxy group, a substituted or unsubstituted aryloxy group, a substituted or unsubstituted arylalkoxy group, a substituted or unsubstituted amino group, a substituted or unsubstituted silyl group, or a cyano group. R 1 and R 2 They can bond together to form a ring. R 3 and R 4 They can bond together to form a ring.

[0414] As the acceptor material used in the P layer, for example, the compound shown in the following general formula (III) can also be used.

[0415]

Chemistry 15

[0416]

[0417] In general formula (III), R 1C ~R 6C Each of the following groups is independently a hydrogen atom, a substituted or unsubstituted aryl group having 6 to 30 carbon atoms, a substituted or unsubstituted pyridyl group, a substituted or unsubstituted quinolinyl group, a substituted or unsubstituted alkyl group having 1 to 30 carbon atoms, a substituted or unsubstituted cycloalkyl group having 3 to 30 carbon atoms, a substituted or unsubstituted aralkyl group having 7 to 50 carbon atoms, a substituted or unsubstituted alkoxy group having 1 to 30 carbon atoms, a substituted or unsubstituted aryloxy group having 6 to 30 carbon atoms, a substituted or unsubstituted aryl thio group having 6 to 30 carbon atoms, a substituted or unsubstituted alkoxycarbonyl group having 2 to 30 carbon atoms, an amino group substituted by a substituted or unsubstituted aryl group having 6 to 30 carbon atoms, a halogen atom, a cyano group, a nitro group, a hydroxyl group, or a carboxyl group.

[0418] <Substrate>

[0419] The substrate is used as a support for the light-emitting element. Materials such as glass, quartz, and plastic can be used as substrates. Flexible substrates can also be used. Flexible substrates are substrates that can be bent (flexible), and examples include plastic substrates formed from polycarbonate, polyarylate, polyethersulfone, polypropylene, polyester, polyvinyl fluoride, and polyvinyl chloride. Inorganic vapor-deposited films can also be used.

[0420] <Anode>

[0421] The anode formed on the substrate is preferably a metal, alloy, conductive compound, or mixture thereof with a high work function (specifically 4.0 eV or higher). Specifically, examples include indium tin oxide (ITO); indium tin oxide containing silicon or silicon oxide; indium zinc oxide; indium oxide containing tungsten oxide and zinc oxide; and graphene. Other examples include gold (Au), platinum (Pt), nickel (Ni), tungsten (W), chromium (Cr), molybdenum (Mo), iron (Fe), cobalt (Co), copper (Cu), palladium (Pd), titanium (Ti), or nitrides of metallic materials (e.g., titanium nitride).

[0422] These materials are typically formed by sputtering. For example, indium oxide-zinc oxide can be formed by sputtering using a target containing 1 to 10 wt% zinc oxide relative to indium oxide; indium oxide containing tungsten oxide and zinc oxide can be formed by sputtering using a target containing 0.5 to 5 wt% tungsten oxide and 0.1 to 1 wt% zinc oxide relative to indium oxide. Alternatively, they can be fabricated using vacuum evaporation, coating, inkjet printing, spin coating, etc.

[0423] The hole injection layer formed in the EL layer on the anode and grounded with the anode is formed using a composite material that is easy to inject holes in, regardless of the work function of the anode. Therefore, materials that can be used as electrode materials (such as metals, alloys, conductive compounds, and mixtures thereof, as well as elements belonging to Group 1 or Group 2 of the periodic table) can be used.

[0424] Elements belonging to Group 1 or Group 2 of the periodic table that have low work functions can also be used, namely alkali metals such as lithium (Li) and cesium (Cs), alkaline earth metals such as magnesium (Mg), calcium (Ca) and strontium (Sr), and alloys containing them (e.g., MgAg, AlLi), rare earth metals such as europium (Eu) and ytterbium (Yb), and alloys containing them. It should be noted that when using alkali metals, alkaline earth metals, and alloys containing them to form the anode, vacuum evaporation or sputtering methods can be used. Furthermore, when using silver paste, coating or inkjet printing methods can be used.

[0425] When the organic EL element is a bottom-emitting type, the anode is preferably formed of a transparent or semi-transparent metallic material that allows light from the emitting layer to pass through. In this specification, transparentness or semi-transparency refers to the property of allowing at least 50% (preferably 80% or more) of the light emitted from the emitting layer to pass through. The transparent or semi-transparent metallic material can be appropriately selected from the materials listed in the above-described anode items.

[0426] When the organic EL element is a top-emitting type, the anode is a reflective electrode with a reflective layer. The reflective layer is preferably formed of a metallic material with light reflectivity. In this specification, light reflectivity refers to the property of reflecting 50% or more (preferably 80% or more) of the light emitted from the light-emitting layer. The metallic material with light reflectivity can be appropriately selected from the materials listed in the above-described anode items.

[0427] The anode may consist of only a reflective layer, or it may be a multilayer structure having a reflective layer and a conductive layer (preferably a transparent conductive layer). When the anode has both a reflective layer and a conductive layer, the conductive layer is preferably disposed between the reflective layer and the hole transport region. The conductive layer may be appropriately selected from the materials listed in the above-described anode items.

[0428] <Cathode>

[0429] The cathode preferably utilizes metals, alloys, conductive compounds, and mixtures thereof with low work functions (specifically, below 3.8 eV). Specific examples of such cathode materials include elements belonging to Group 1 or Group 2 of the periodic table, namely alkali metals such as lithium (Li) and cesium (Cs), alkaline earth metals such as magnesium (Mg), calcium (Ca), and strontium (Sr), as well as alloys containing them (e.g., MgAg, AlLi), rare earth metals such as europium (Eu) and ytterbium (Yb), as well as alloys containing them.

[0430] It should be noted that when using alkali metals, alkaline earth metals, or alloys containing them to form the cathode, vacuum evaporation or sputtering methods can be used. Additionally, when using silver paste, coating or inkjet printing methods can be used.

[0431] It should be noted that by setting an electron injection layer, various conductive materials such as Al, Ag, ITO, graphene, and indium tin oxide containing silicon or silicon oxide can be used to form cathodes, regardless of the work function. These conductive materials can be deposited using sputtering, inkjet printing, spin coating, and other methods.

[0432] When the organic EL element is a bottom-emitting type, the cathode is a reflective electrode. The reflective electrode is preferably formed of a light-reflective metallic material. The light-reflective metallic material can be appropriately selected from the materials listed in the cathode section above.

[0433] When the organic EL element is a top-emitting type, the cathode is preferably formed of a transparent or semi-transparent metallic material that allows light from the light-emitting layer to pass through. The transparent or semi-transparent metallic material can be appropriately selected from the materials listed in the cathode items above.

[0434] <Capping Layer>

[0435] When an organic EL element is a top-emitting type, the organic EL element usually has a capping layer on the top of the cathode.

[0436] As a capping layer, for example, polymer compounds, metal oxides, metal fluorides, metal borides, silicon nitrides, and silicon compounds (silicon oxides, etc.) can be used.

[0437] Alternatively, aromatic amine derivatives, anthracene derivatives, pyrene derivatives, fluorene derivatives, or dibenzofuran derivatives can also be used as capping layers.

[0438] In addition, a laminate containing these substances can also be used as a capping layer.

[0439] (Layer thickness)

[0440] In organic EL devices, the thickness of the light-emitting layer and other layers disposed between the anode and cathode is not particularly limited unless otherwise specified above. Generally speaking, if the layer thickness is too thin, defects such as pinholes are easily generated. Conversely, if the thickness is too thick, a high applied voltage is required, resulting in poor efficiency. Therefore, the preferred thickness is usually in the range of several nm to 1 μm.

[0441] (Manufacturing method of organic EL device)

[0442] There are no particular restrictions on the manufacturing method of organic EL devices; the manufacturing methods used for organic EL devices in the past can be used. Specifically, various layers can be formed on the substrate by vacuum evaporation, casting, coating, spin coating, etc.

[0443] In addition to casting, coating, and spin coating methods using solutions of organic materials dispersed in transparent polymers such as polycarbonate, polyurethane, polystyrene, polyarylate, and polyester, it can also be formed by simultaneous vapor deposition of organic materials and transparent polymers.

[0444] [Second Implementation]

[0445] The organic EL element of the second embodiment is an organic EL element in which the hole transport region (third hole transport region) of the third light-emitting unit contains two or more hole transport layers. In other respects, it is the same as the organic EL element of the first embodiment, therefore descriptions are omitted or simplified.

[0446] It is believed that in the organic EL element of the second embodiment, the third hole transport region includes two or more hole transport layers, thereby enabling effective hole injection from the second charge generation layer.

[0447] Here, the hole transport layer sometimes also has an electron blocking function, and is therefore sometimes called the electron blocking layer.

[0448] The materials contained in the hole transport layer typically possess exciton resistance. Therefore, by configuring two or more hole transport layers in the third hole transport region, the degradation of the interface between the hole transport layer and the third light-emitting layer can be suppressed. This makes it easier to improve the lifetime of organic EL devices.

[0449] Furthermore, the material contained in the hole transport layer typically has a larger band gap than the host material (e.g., compound BH used in the embodiment) contained in the third luminescent layer. Therefore, by configuring two or more hole transport layers in the third hole transport region, the luminescent energy of the third luminescent layer can be effectively confined, thus suppressing the deactivation of luminescent energy. This also facilitates the improvement of luminescent efficiency.

[0450] Therefore, the organic EL element according to the second embodiment can reduce the driving voltage and increase the lifetime. Furthermore, an increase in luminous efficiency (preferably the luminous efficiency of blue fluorescence emission) is also expected.

[0451] From the viewpoint of further demonstrating the effect of this embodiment, the hole transport region (third hole transport region) of the third light-emitting unit is preferably formed of two or more layers (preferably two or more layers and four or fewer layers), and more preferably two layers. Specifically, it is more preferably formed of two hole transport layers.

[0452] From the viewpoint of further demonstrating the effect of this embodiment, the hole transport region (second hole transport region) of the second light-emitting unit is preferably formed of two or more layers (preferably two or more layers and four or fewer layers), and more preferably two layers. Specifically, it is more preferably formed of two hole transport layers.

[0453] The hole transport region (first hole transport region) of the first light-emitting unit is preferably formed of 3 or more layers (preferably 3 or more layers and 5 or less), and more preferably 3 layers. Specifically, it is preferably formed of 1 hole injection layer connected to the anode side and 2 hole transport layers stacked on the hole injection layer.

[0454] Figure 3 This is a diagram showing the general configuration of an example of an organic EL element according to the second embodiment.

[0455] Figure 3 The organic EL element represented is relative to Figure 1 The organic EL element 1 shown differs from the organic EL element of the first embodiment in that the third hole transport region and the second hole transport region contain two hole transport layers, and the first hole transport region contains one hole injection layer and two hole transport layers.

[0456] Specifically, the organic EL element 2 is constructed by sequentially stacking an anode 12, a first light-emitting unit 13A, a first charge-generating layer 14, a second light-emitting unit 15A, a second charge-generating layer 16, a third light-emitting unit 17A, and a cathode 18 on a substrate 11.

[0457] The thickness d3(d) of the third hole transport region 171 31 and d 32 The total thickness of the first layer (dN) is between 10nm and 30nm, which is thinner than the thickness of the second N layer (dN).

[0458] The third hole transport region 171 includes, from the anode side, a first hole transport layer 171A and a second hole transport layer 171B in sequence. The first hole transport layer 171A is connected to the P layer 162 of the second charge generation layer 16.

[0459] The second hole transport region 151 includes, from the anode side, a first hole transport layer 151A and a second hole transport layer 151B in sequence. The first hole transport layer 151A is connected to the P layer 142 of the first charge generation layer 14.

[0460] The first hole transport region 131 includes, from the anode side, a hole injection layer 131C, a first hole transport layer 131A, and a second hole transport layer 131B in sequence, with the hole injection layer 131C connected to the anode 12.

[0461] The thickness of the first hole transport layer in each hole transport region ( Figure 3 The middle is d 11 d 21 、 and d 31 Each of the elements is preferably 2nm or more and 38nm or less, more preferably 5nm or more and 25nm or less, and even more preferably 5nm or more and 15nm or less.

[0462] The thickness of the second hole transport layer in each hole transport region ( Figure 3 The middle is d 12 d 22 、 and d 32 Each of the elements is preferably 2nm or more and 38nm or less, more preferably 5nm or more and 25nm or less, and even more preferably 5nm or more and 15nm or less.

[0463] The ratio of the thickness of the second hole transport layer to the thickness of the first hole transport layer in each hole transport region ( Figure 3 The middle is d 12 / d 11 d 22 / d 21 、 and d 32 / d 31Each of the following is preferably 0.05 or more and 19 or less, more preferably 0.2 or more and 5 or less, and even more preferably 0.3 or more and 3 or less.

[0464] [Third Implementation Method]

[0465] [Electronic Devices]

[0466] The electronic device of this embodiment incorporates the organic EL element of the first or second embodiment. Examples of electronic devices include display devices and light-emitting devices. Examples of display devices include display components (e.g., organic EL panel modules), televisions, mobile phones, tablet computers, and personal computers. Examples of light-emitting devices include lighting and vehicle lamps.

[0467] The electronic device according to this embodiment, by incorporating the organic EL element of this embodiment, can reduce the driving voltage and increase its lifespan.

[0468] In this specification, the numerical range indicated by “~” refers to the range included by taking the value recorded before “~” as the lower limit and the value recorded after “~” as the upper limit.

[0469] In this specification, the mutual bonding of Rx and Ry to form a ring means, for example, that Rx and Ry contain carbon, nitrogen, oxygen, sulfur, or silicon atoms, and that the atoms (carbon, nitrogen, oxygen, sulfur, or silicon) in Rx are bonded to the atoms (carbon, nitrogen, oxygen, sulfur, or silicon) in Ry via single, double, triple, or divalent connecting groups, forming a ring with 5 or more carbon atoms (specifically, a heterocyclic or aromatic hydrocarbon ring). x is a number, a letter, or a combination of numbers and letters. y is a number, a letter, or a combination of numbers and letters.

[0470] There are no particular limitations on the divalent linking group. Examples include -O-, -CO-, -CO2-, -S-, -SO-, -SO2-, -NH-, -NRa-, and groups composed of two or more of these linking groups.

[0471] As a specific example of a heterocycle, one can cite the ring structure (heterocycle) formed by removing the connecting bonds from the "heteroaryl group with 5 to 30 cyclic atoms" illustrated in the "Explanation of Substituents in the General Formula" described later. These heterocycles may have substituents.

[0472] As a specific example of an aromatic hydrocarbon ring, one can cite the ring structure (aromatic hydrocarbon ring) formed by removing the linking bond from the "aryl group having 6 to 30 carbon atoms" illustrated in the "Explanation of Substituents in the General Formula" described later. These aromatic hydrocarbon rings may have substituents.

[0473] Examples of Ra include alkyl groups with 1 to 30 carbon atoms that are substituted or unsubstituted, aryl groups with 6 to 30 carbon atoms that are substituted or unsubstituted, and heteroaryl groups with 5 to 30 carbon atoms that are substituted or unsubstituted.

[0474] For example, the formation of a ring by mutual bonding of Rx and Ry means that, in the molecular structure shown by the general formula (E1), the atoms contained in Rx1 and the atoms contained in Ry1 form a ring (ring structure) E as shown by the general formula (E2); in the molecular structure shown by the general formula (F1), the atoms contained in Rx1 and the atoms contained in Ry1 form a ring F represented by the general formula (F2); in the molecular structure shown by the general formula (G1), the atoms contained in Rx1 and the atoms contained in Ry1 form a ring G as shown by the general formula (G2); in the molecular structure shown by the general formula (H1), the atoms contained in Rx1 and the atoms contained in Ry1 form a ring H as shown by the general formula (H2); and in the molecular structure shown by the general formula (I1), the atoms contained in Rx1 and the atoms contained in Ry1 form a ring I as shown by the general formula (I2).

[0475] In general formulas (E1) to (I1), each * independently represents a bonding position with other atoms in a molecule. The two * in general formula (E1) correspond to the two * in general formula (E2), the two * in general formula (F1) correspond to the two * in general formula (F2), the two * in general formula (G1) correspond to the two * in general formula (G2), the two * in general formula (H1) correspond to the two * in general formula (H2), and the two * in general formula (I1) correspond to the two * in general formula (I2).

[0476]

Chemistry 16

[0477]

[0478]

Chemistry 17

[0479]

[0480] In the molecular structures represented by general formulas (E2) to (I2), E to I each represent a ring structure (a ring with 5 or more ring atoms). In general formulas (E2) to (I2), each * independently represents a bonding position with other atoms in a molecule. The two * in general formula (E2) correspond to the two * in general formula (E1). Similarly, the two * in general formulas (F2) to (I2) correspond to the two * in general formulas (F1) to (I1).

[0481] For example, in general formula (E1), when Rx1 and Ry1 are bonded together to form ring E in general formula (E2), and ring E is an unsubstituted benzene ring, the molecular structure shown in general formula (E1) becomes the molecular structure shown in general formula (E3) below. Here, the two asterisks in general formula (E3) each independently correspond to the two asterisks in general formula (E2) and general formula (E1).

[0482] For example, in general formula (E1), when Rx1 and Ry1 bond to each other to form ring E in general formula (E2), and ring E is an unsubstituted pyrrole ring, the molecular structure shown in general formula (E1) becomes the molecular structure shown in general formula (E4) below. Here, the two asterisks in general formula (E4) each independently correspond to the two asterisks in general formula (E2) and general formula (E1). In general formulas (E3) and (E4), each asterisk independently indicates a bonding position with other atoms in a molecule.

[0483] [Chemistry 18]

[0484]

[0485] In this specification, the number of carbon atoms forming a ring refers to the number of carbon atoms in the atoms constituting the ring itself in a compound with a cyclic structure formed by atomic bonds (e.g., monocyclic compounds, fused-ring compounds, bridged-ring compounds, carbocyclic compounds, heterocyclic compounds). When the ring is substituted with a substituent, the carbon atoms contained in the substituent are not included in the number of carbon atoms forming the ring. Unless otherwise specified, the term "number of carbon atoms forming the ring" as used below has the same meaning. For example, the number of carbon atoms forming the ring of a benzene ring is 6, the number of carbon atoms forming the ring of a naphthalene ring is 10, the number of carbon atoms forming the ring of a pyridyl group is 5, and the number of carbon atoms forming the ring of a furanyl group is 4. Furthermore, when an alkyl group, for example, is substituted as a substituent on a benzene or naphthalene ring, the number of carbon atoms in that alkyl group is not included in the number of carbon atoms forming the ring. Additionally, when a fluorene ring (including a spirofluorene ring) is bonded as a substituent on a fluorene ring, the number of carbon atoms in the fluorene ring that is the substituent is not included in the number of carbon atoms forming the ring.

[0486] In this specification, the number of cyclic atoms refers to the number of atoms constituting the ring itself in compounds with a cyclic structure (e.g., monocyclic, fused-ring, aggregated ring) formed by atomic bonds (e.g., monocyclic compounds, fused-ring compounds, bridged-ring compounds, carbocyclic compounds, heterocyclic compounds). Atoms that do not constitute a ring, and atoms contained in substituents when the ring is substituted, are not included in the number of cyclic atoms. Unless otherwise specified, "number of cyclic atoms" as used below has the same meaning. For example, the number of cyclic atoms in a pyridine ring is 6, in a quinazoline ring it is 10, and in a furan ring it is 5. Hydrogen atoms bonded to the carbon atoms of the pyridine and quinazoline rings, and atoms constituting substituents, are not included in the number of cyclic atoms. Furthermore, in cases where a fluorene ring (including spirofluorene ring) is bonded to a fluorene ring as a substituent, the number of atoms in the fluorene ring as a substituent is not included in the number of cyclic atoms.

[0487] • Description of each substituent in the general formula in this specification (Description of each substituent)

[0488] Examples of aryl groups (sometimes referred to as aromatic hydrocarbon groups) with 6 to 30 carbon atoms in this specification include, for example, phenyl, biphenyl, terphenyl, naphthyl, anthraceneyl, phenanthryl, fluorenyl, pyrene, etc. Benzyl, fluoranthryl, benzo[a]anthrayl, benzo[c]phenanthryl, triphenylene, benzo[k]fluoranthryl, benzo[g] Benzyl, benzo[b]triphenylene, styrene, and perylene, etc.

[0489] The aryl group used in this specification preferably has 6 to 20 carbon atoms in the cyclic ring, more preferably 6 to 14, and even more preferably 6 to 12. Among the above-mentioned aryl groups, phenyl, biphenyl, naphthyl, phenanthryl, terphenyl, and fluorenyl are even more preferred. For 1-fluorenyl, 2-fluorenyl, 3-fluorenyl, and 4-fluorenyl groups, the carbon atom at position 9 is preferably substituted with an alkyl group having 1 to 30 carbon atoms, or a substituted or unsubstituted aryl group having 6 to 18 carbon atoms in the cyclic ring, as described later in this specification.

[0490] The heteroaryl group (sometimes called heterocyclic group, heteroaromatic cyclic group, or aromatic heterocyclic group) with 5 to 30 cyclic atoms in this specification preferably includes at least one atom selected from the group consisting of nitrogen, sulfur, oxygen, silicon, selenium and germanium atoms, and more preferably includes at least one atom selected from the group consisting of nitrogen, sulfur and oxygen.

[0491] Examples of heterocyclic groups with 5 to 30 cyclic atoms as used in this specification include: pyridinyl, pyrimidinyl, pyrazinyl, pyridazinyl, triazinyl, quinolinyl, isoquinolinyl, naphthidyl, phthalazinyl, quinoxalinyl, quinazolinyl, phenanthridine, acridineyl, phenanthroxolinyl, pyrroleyl, imidazolyl, pyrazolyl, triazolyl, tetrazolyl, indoleyl, benzimidazolyl, indazolyl, imidazopyridyl, benzotriazolyl, carboxyl, etc. Azolyl, furanyl, thiophene, oxazolyl, thiazolyl, isoxazolyl, isothiazolyl, oxadiazolyl, thiazolyl, benzofuranyl, benzothiophene, benzooxazolyl, benzothiazolyl, benzoisooxazolyl, benzoisothiazolyl, benzooxadiazolyl, dibenzofuranyl, dibenzothiophene, piperidinyl, pyrrolylyl, piperazinyl, morpholinyl, phenazinyl, phenthiazinyl, and phenoxazinyl, etc.

[0492] The heterocyclic group in this specification preferably has 5 to 20 cyclic atoms, more preferably 5 to 14. Among the aforementioned heterocyclic groups, 1-dibenzofuranyl, 2-dibenzofuranyl, 3-dibenzofuranyl, 4-dibenzofuranyl, 1-dibenzothiophenyl, 2-dibenzothiophenyl, 3-dibenzothiophenyl, 4-dibenzothiophenyl, 1-carbazoleyl, 2-carbazoleyl, 3-carbazoleyl, 4-carbazoleyl, and 9-carbazoleyl are even more preferred. For 1-carbazoleyl, 2-carbazoleyl, 3-carbazoleyl, and 4-carbazoleyl, the nitrogen atom at position 9 is preferably substituted with an aryl group having 6 to 30 cyclic carbon atoms, or a heterocyclic group having 5 to 30 cyclic atoms, as specified in this specification.

[0493] In addition, in this specification, the heterocyclic group can be a group derived, for example, from the local structure shown in the following general formulas (XY-1) to (XY-18).

[0494]

Chemistry 19

[0495]

[0496]

Chemistry 20

[0497]

[0498]

Chemistry 21

[0499]

[0500] In the above general formulas (XY-1) to (XY-18), X A and Y A Each atom is an independent heteroatom, preferably an oxygen atom, sulfur atom, selenium atom, silicon atom, or germanium atom. The local structures shown in the above general formulas (XY-1) to (XY-18) have connecting bonds at optional positions to form heterocyclic groups, which may have substituents.

[0501] Furthermore, in this specification, the substituted or unsubstituted carbazole group may, for example, include a group formed by further fused ring-forming of the carbazole ring as shown in the following general formulas (XY-19) to (XY-22). Such a group may also have substituents. In addition, the position of the linking bond may be appropriately changed.

[0502]

Chemistry 22

[0503]

[0504] The alkyl group having 1 to 30 carbon atoms in this specification can be any type of straight-chain, branched, or cyclic alkyl group. Alternatively, it can be a haloalkyl group.

[0505] Examples of straight-chain or branched alkyl groups include methyl, ethyl, n-propyl, isopropyl, n-butyl, sec-butyl, isobutyl, tert-butyl, n-pentyl, n-hexyl, n-heptyl, n-octyl, n-nonyl, n-decyl, n-undecyl, n-dodecyl, n-tridecyl, n-tetradecyl, n-pentadecanyl, n-hexadecyl, n-heptadecyl, n-octadecyl, neopentyl, pentyl, isopentyl, 1-methylpentyl, 2-methylpentyl, 1-pentylhexyl, 1-butylpentyl, 1-heptyloctyl, and 3-methylpentyl.

[0506] The number of carbon atoms in the straight-chain or branched alkyl groups in this specification is preferably 1 to 10, and more preferably 1 to 6. Among the above-mentioned straight-chain or branched alkyl groups, methyl, ethyl, propyl, isopropyl, n-butyl, sec-butyl, isobutyl, tert-butyl, n-pentyl, n-hexyl, pentyl, isopentyl, and neopentyl are even more preferred.

[0507] Examples of cyclic alkyl groups as used in this specification include cycloalkyl groups having 3 to 30 carbon atoms.

[0508] Examples of cycloalkyl groups with 3 to 30 carbon atoms in the ring as used in this specification include cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, 4-methylcyclohexyl, adamantyl, and norbornyl. The number of carbon atoms in the ring of the cycloalkyl group is preferably 3 to 10, and more preferably 5 to 8. Among the above-mentioned cycloalkyl groups, cyclopentyl and cyclohexyl are even more preferred.

[0509] As a haloalkyl group formed by substituting halogen atoms into alkyl groups in this specification, examples include groups formed by substituting one or more halogen atoms, preferably fluorine atoms, into alkyl groups having 1 to 30 carbon atoms.

[0510] Examples of halogenated alkyl groups having 1 to 30 carbon atoms in this specification include fluoromethyl, difluoromethyl, trifluoromethyl, fluoroethyl, trifluoromethylmethyl, trifluoroethyl, and pentafluoroethyl.

[0511] Examples of substituted silyl groups in this specification include alkylsilyl groups having 3 to 30 carbon atoms and arylsilyl groups having 6 to 30 carbon atoms.

[0512] Examples of alkylsilyl groups having 3 to 30 carbon atoms in this specification include trialkylsilyl groups having alkyl groups exemplified among the alkyl groups having 1 to 30 carbon atoms. Specifically, these include trimethylsilyl, triethylsilyl, tri-n-butylsilyl, tri-n-octylsilyl, triisobutylsilyl, dimethylethylsilyl, dimethylisopropylsilyl, dimethyl-n-propylsilyl, dimethyl-n-butylsilyl, dimethyl-tert-butylsilyl, diethylisopropylsilyl, vinyldimethylsilyl, propyldimethylsilyl, and triisopropylsilyl. The three alkyl groups in a trialkylsilyl group may be the same or different from each other.

[0513] Examples of arylsilyl groups with 6 to 30 carbon atoms in this specification include dialkylarylsilyl groups, alkyldiarylsilyl groups, and triarylsilyl groups.

[0514] Examples of dialkylarylsilyl compounds include those having two alkyl groups exemplified from the above-described alkyl groups having 1 to 30 carbon atoms, and those having one aryl group having 6 to 30 carbon atoms in a cyclic formation. The preferred carbon number of the dialkylarylsilyl compound is 8 to 30.

[0515] Examples of alkyl diarylsilyl compounds include those having one alkyl group from the alkyl groups with 1 to 30 carbon atoms, and those having two aryl groups with 6 to 30 carbon atoms in the cyclic formation. The preferred carbon number of the alkyl diarylsilyl compound is 13 to 30.

[0516] Examples of triarylsilanes include triarylsilanes having three aryl groups having 6 to 30 carbon atoms in the cyclic formation described above. The preferred number of carbon atoms in a triarylsilane is 18 to 30.

[0517] In this specification, the alkyl sulfonyl group is represented by -SO2R w express. -SO2R w R in w Indicates substituted or unsubstituted alkyl groups.

[0518] Examples of substituted or unsubstituted alkyl sulfonyl groups having 1 to 30 carbon atoms in this specification include the aforementioned -SO2R. w R in w The group consisting of a substituted or unsubstituted alkyl group having 1 to 30 carbon atoms.

[0519] In this specification, the aryl group in aralkyl (sometimes referred to as arylalkyl) is an aromatic hydrocarbon group or a heterocyclic group.

[0520] In the present specification, the aralkyl group having 7 to 30 carbon atoms is preferably a group having an aryl group with 6 to 30 ring-forming carbon atoms, represented as -Z3-Z4. Examples of Z3 include an alkylene group corresponding to the above-mentioned alkyl group having 1 to 30 carbon atoms. Examples of Z4 include, for example, the above-mentioned aryl groups with 6 to 30 ring-forming carbon atoms. The aralkyl group preferably has an aryl part with 6 to 30 carbon atoms (preferably 6 to 20, more preferably 6 to 12) and an alkyl part with 1 to 30 carbon atoms (preferably 1 to 20, more preferably 1 to 10, further preferably 1 to 6). Examples of the aralkyl group include, for example: benzyl, 2-phenylpropan-2-yl, 1-phenylethyl, 2-phenylethyl, 1-phenylisopropyl, 2-phenylisopropyl, phenyl tert-butyl, α-naphthylmethyl, 1-α-naphthylethyl, 2-α-naphthylethyl, 1-α-naphthylisopropyl, 2-α-naphthylisopropyl, β-naphthylmethyl, 1-β-naphthylethyl, 2-β-naphthylethyl, 1-β-naphthylisopropyl, and 2-β-naphthylisopropyl, etc.

[0521] The alkoxy group having 1 to 30 carbon atoms in the present specification is expressed as -OZ¹. Examples of Z¹ include the above-mentioned alkyl groups having 1 to 30 carbon atoms. Examples of the alkoxy group include, for example, methoxy, ethoxy, propoxy, butoxy, pentyloxy, and hexyloxy, etc. The carbon number of the alkoxy group is preferably 1 to 20.

[0522] As the haloalkoxy group formed by substituting a halogen atom for the alkoxy group, for example, a group formed by substituting one or more fluorine atoms for the above-mentioned alkoxy group having 1 to 30 carbon atoms can be cited.

[0523] In the present specification, the aryl group in the aryloxy group (sometimes referred to as an aralkyloxy group (original Japanese: アリールアルコキシ基)) also includes a heteroaryl group.

[0524] The aralkyloxy group having 6 to 30 ring-forming carbon atoms in the present specification is expressed as -OZ². Examples of Z² include, for example, the above-mentioned aryl groups with 6 to 30 ring-forming carbon atoms. The ring-forming carbon number of the aralkyloxy group is preferably 6 to 20. Examples of the aralkyloxy group include, for example, phenoxy.

[0525] The substituted amino group in the present specification is expressed as -NHR V 、or -N(R V )₂. Examples of R V include, for example, the above-mentioned alkyl groups having 1 to 30 carbon atoms, and the above-mentioned aryl groups with 6 to 30 ring-forming carbon atoms, etc.

[0526] The alkenyl group having 2 to 30 carbon atoms in this specification can be any type of straight chain or branched chain, such as vinyl, propenyl, butenyl, oleyl, eicosaptenyl, docosahexaenoyl, styryl, 2,2-diphenylvinyl, 1,2,2-triphenylvinyl, and 2-phenyl-2-propenyl.

[0527] The alkynyl group with 2 to 30 carbon atoms in this specification can be any type of straight chain or branched chain, such as ethynyl, propynyl, and 2-phenylethynyl.

[0528] In this specification, alkylthio groups with 1 to 30 carbon atoms and arylthio groups with 6 to 30 carbon atoms are represented as -SR. V As the R V Examples include alkyl groups with 1 to 30 carbon atoms and aryl groups with 6 to 30 carbon atoms in the cyclic formation. The alkylthio group preferably has 1 to 20 carbon atoms. The arylthio group preferably has 6 to 20 carbon atoms in the cyclic formation.

[0529] Examples of halogen atoms in this specification include fluorine atoms, chlorine atoms, bromine atoms, and iodine atoms, with fluorine atoms being preferred.

[0530] Examples of substituted phosphine groups in this specification include, for example, phenylphosphine.

[0531] In this specification, aryl carbonyl groups with 6 to 30 carbon atoms in a cyclic structure are represented as -COY'. Examples of this Y' include the aforementioned "aryl group with 6 to 30 carbon atoms in a cyclic structure". Examples of aryl carbonyl groups with 6 to 30 carbon atoms in a cyclic structure in this specification include, for example, phenyl carbonyl, diphenyl carbonyl, naphthyl carbonyl, and triphenyl carbonyl.

[0532] In this specification, acyl groups having 2 to 31 carbon atoms are represented as -COR'. Examples of this R' include alkyl groups having 1 to 30 carbon atoms as described above. Examples of acyl groups having 2 to 31 carbon atoms in this specification include, for example, acetyl and propionyl groups.

[0533] The substituted phosphoryl groups in this specification are represented by the following general formula (P).

[0534]

Chemistry 23

[0535]

[0536] In the above general formula (P), Ar P1 and Ar P2Examples of substituents include any substituent selected from the group consisting of alkyl groups having 1 to 30 carbon atoms (preferably 1 to 10 carbon atoms, more preferably 1 to 6 carbon atoms) and aryl groups having 6 to 30 cyclic carbon atoms (preferably 6 to 20 cyclic carbon atoms, more preferably 6 to 14 cyclic carbon atoms). Examples of alkyl groups having 1 to 30 carbon atoms include the aforementioned alkyl groups. Examples of aryl groups having 6 to 30 cyclic carbon atoms include the aforementioned aryl groups.

[0537] Examples of ester groups used in this specification include alkyl ester groups. Alkyl ester groups are represented as -C(=O)OR E As R E Examples can be given of the above alkyl groups, whether substituted or unsubstituted.

[0538] In this specification, siloxane refers to a silicon compound group separated by an ether bond, such as trimethylsiloxane.

[0539] In this specification, "cyclic carbon" refers to the carbon atom that constitutes a saturated ring, an unsaturated ring, or an aromatic ring. "Cyclic atom" refers to the carbon atom and heteroatom that constitute a heterocycle (including saturated rings, unsaturated rings, and aromatic rings).

[0540] In addition, in this specification, hydrogen atoms include isotopes with different numbers of neutrons, namely protium, deuterium, and tritium.

[0541] In this specification, when described as "substituted or unsubstituted", examples of substituents include at least one group selected from the group consisting of an aryl group having 6 to 30 carbon atoms in a ring, a heteroaryl group having 5 to 30 carbon atoms in a ring, a straight-chain alkyl group having 1 to 30 carbon atoms, a branched alkyl group having 3 to 30 carbon atoms, a cycloalkyl group having 3 to 30 carbon atoms in a ring, a haloalkyl group having 1 to 30 carbon atoms, a substituted or unsubstituted silyl group (e.g., an alkylsilyl group having 3 to 30 carbon atoms, and an arylsilyl group having 6 to 30 carbon atoms in a ring), an alkoxy group having 1 to 30 carbon atoms, an aryloxy group having 6 to 30 carbon atoms in a ring, a substituted or unsubstituted amino group, an alkylthio group having 1 to 30 carbon atoms, an arylthio group having 6 to 30 carbon atoms in a ring, an arylalkyl group having 7 to 30 carbon atoms, an alkenyl group having 2 to 30 carbon atoms, a halogen atom, an alkynyl group having 2 to 30 carbon atoms, a cyano group, a hydroxyl group, a nitro group, a carboxyl group, and a substituted phosphoryl group.

[0542] In this specification, diarylboryl (Ar) can also be cited as a substituent when described as "substituted or unsubstituted". B1 Ar B2 B-). As the Ar B1 and Ar B2 An example of this could be the aforementioned "aryl groups with 6 to 30 carbon atoms in a ring".

[0543] As specific examples and preferred groups of substituents described as "substituted or unsubstituted", groups that are the same as those in the "Description of Substituents" can be cited.

[0544] When described as "substituted or unsubstituted," the substituents may be further substituted with at least one group selected from the group consisting of aryl (6-30 carbon atoms), heteroaryl (5-30 carbon atoms), straight-chain alkyl (1-30 carbon atoms), branched alkyl (3-30 carbon atoms), cycloalkyl (3-30 carbon atoms), haloalkyl (1-30 carbon atoms), alkylsilyl (3-30 carbon atoms), arylsilyl (6-30 carbon atoms), alkoxy (1-30 carbon atoms), aryloxy (6-30 carbon atoms), substituted amino, alkylthio (1-30 carbon atoms), arylthio (6-30 carbon atoms), arylalkyl (7-30 carbon atoms), alkenyl (2-30 carbon atoms), alkynyl (2-30 carbon atoms), halogen atom, cyano, hydroxyl, nitro, and carboxyl. Furthermore, two or more of these substituents may be bonded together to form a ring.

[0545] When expressed as "substituted or unsubstituted", "unsubstituted" means that it is not substituted by the aforementioned substituents but is bonded with hydrogen atoms.

[0546] It should be noted that in this specification, the "carbon number XX to YY" in the expression "ZZ group with substituted or unsubstituted carbon number XX to YY" refers to the carbon number when the ZZ group is unsubstituted, and the carbon number of the substituent when substituted is not included.

[0547] In this specification, the "number of atoms XX to YY" in the expression "ZZ group with substituted or unsubstituted atoms" refers to the number of atoms when the ZZ group is unsubstituted, and the number of atoms of the substituents when substituted is not included.

[0548] The same applies to compounds or parts thereof described in this specification that are described as "substituted or unsubstituted".

[0549] In this specification, when substituents bond together to form a ring, the ring structure is a saturated ring, an unsaturated ring, an aromatic hydrocarbon ring, or a heterocyclic ring.

[0550] In this specification, the aromatic hydrocarbon group, heterocyclic group, etc., in the linking group can be a divalent or higher group obtained by removing one or more atoms from the above-mentioned monovalent group.

[0551] Example

[0552] The following describes embodiments of the present invention. The present invention is not limited to these embodiments in any way.

[0553] <Compound>

[0554] The following shows the compounds used in the manufacture of organic EL elements.

[0555]

Chemistry 24

[0556]

[0557]

Chemistry 25

[0558]

[0559]

Chemistry 26

[0560]

[0561]

Chemistry 27

[0562]

[0563]

Chemistry 28

[0564]

[0565]

Chemistry 29

[0566]

[0567]

Transformation 30

[0568]

[0569]

Chemistry 31

[0570]

[0571]

Chemistry 32

[0572]

[0573]

Transformation 33

[0574]

[0575]

Transformation 34

[0576]

[0577]

Chemistry 35

[0578]

[0579]

Transformation 36

[0580]

[0581] <Fabrication of Organic EL Components>

[0582] The following describes how to fabricate an organic EL element.

[0583] (Example 1)

[0584] A glass substrate (manufactured by Geomatec Corporation) with an ITO transparent electrode (anode) and a thickness of 25mm × 75mm × 1.1mm was ultrasonically cleaned in isopropanol for 5 minutes, followed by UV ozone cleaning for 1 minute. The ITO film thickness was 130nm.

[0585] • Formation of the first light-emitting unit

[0586] The cleaned glass substrate with transparent electrode lines was mounted on the substrate holder of a vacuum evaporation apparatus. First, compound HT-1 and compound HI were co-deposited on the side with the transparent electrode lines to cover the transparent electrode, forming a hole injection layer with a thickness of 10 nm. The concentration of compound HT-1 in the hole injection layer was set to 97% by mass, and the concentration of compound HI was set to 3% by mass.

[0587] Next, compound HT-1 was deposited on the hole injection layer to form a first hole transport layer with a thickness of 117 nm.

[0588] Next, compound HT-2 was deposited on the first hole transport layer to form a second hole transport layer with a thickness of 10 nm.

[0589] Next, compounds PGH-1 and PGD were co-deposited on the second hole transport layer to form a yellow phosphorescent layer with a thickness of 40 nm, serving as the first emitting layer. The concentration of compound PGH-1 in the yellow phosphorescent layer was set to 80% by mass, and the concentration of compound PGD was set to 20% by mass.

[0590] Next, compound ET-1 was deposited on the yellow phosphorescent layer to form an electron transport layer with a thickness of 10 nm.

[0591] • Formation of the first charge generation layer

[0592] Next, compound ET-2 and lithium (Li) were co-deposited on the electron transport layer to form a first N layer with a thickness of 10 nm. The concentration of compound ET-2 in the first N layer was set to 96% by mass, and the concentration of Li was set to 4% by mass.

[0593] Next, compound HT-1 and compound HI were co-deposited on the first N layer to form a first P layer with a thickness of 10 nm. The concentration of compound HT-1 in the first P layer was set to 90% by mass, and the concentration of compound HI was set to 10% by mass.

[0594] • Formation of the second light-emitting unit

[0595] Next, compound HT-1 was deposited on the first P layer to form a first hole transport layer with a thickness of 10 nm.

[0596] Next, compound HT-2 was deposited on the first hole transport layer to form a second hole transport layer with a thickness of 10 nm.

[0597] Next, compounds BH and BD-1 were co-deposited on the second hole transport layer to form a blue fluorescent emissive layer with a thickness of 25 nm, serving as the second emissive layer. The concentration of compound BH in the blue fluorescent emissive layer was set to 96% by mass, and the concentration of compound BD-1 was set to 4% by mass.

[0598] Next, compound PGH-2 was deposited on the blue fluorescent emitting layer to form an electron transport layer with a thickness of 10 nm.

[0599] • Formation of the second charge generation layer

[0600] Next, compound ET-2 and lithium (Li) were co-deposited on the electron transport layer to form a second N layer with a thickness of 56 nm. The concentration of compound ET-2 in the second N layer was set to 96% by mass, and the concentration of Li was set to 4% by mass.

[0601] Next, compound HT-1 and compound HI were co-deposited on the second N layer to form a second P layer with a thickness of 10 nm. The concentration of compound HT-1 in the second P layer was set to 90% by mass, and the concentration of compound HI was set to 10% by mass.

[0602] • Formation of the third light-emitting unit

[0603] Next, compound HT-1 was deposited on the second P layer to form a first hole transport layer with a thickness of 10 nm.

[0604] Next, compound HT-2 was deposited on the first hole transport layer to form a second hole transport layer with a thickness of 10 nm.

[0605] Next, compounds BH and BD-1 were co-deposited on the second hole transport layer to form a blue fluorescent emissive layer with a thickness of 25 nm, serving as the third emissive layer. The concentration of compound BH in the blue fluorescent emissive layer was set to 96% by mass, and the concentration of compound BD-1 was set to 4% by mass.

[0606] Next, compound PGH-2 was deposited on the blue fluorescent emitting layer to form a first electron transport layer with a thickness of 10 nm.

[0607] Next, compound ET-1 was deposited on the first electron transport layer to form a second electron transport layer with a thickness of 12 nm.

[0608] Next, lithium fluoride (LiF) was deposited on the second electron transport layer to form an electron injection layer with a thickness of 1 nm.

[0609] Then, metallic aluminum (Al) was deposited on the electron injection layer to form a metallic Al cathode with a film thickness of 80 nm.

[0610] Bottom-emitting organic EL devices are manufactured in accordance with the above method.

[0611] If the component configuration of the organic EL element of Example 1 is shown in a simplified manner, it is as follows.

[0612] ITO(130) /

[0613] HT-1:HI(10, 97%:3%) / HT-1(117) / HT-2(10) / PGH-1:PGD(40, 80%:20%) / ET-1(10) /

[0614] ET-2:Li(10,96%:4%) / HT-1:HI(10,90%:10%) /

[0615] HT-1(10) / HT-2(10) / BH:BD-1(25, 96%:4%) / PGH-2(10) /

[0616] ET-2: Li (56, 96%: 4%) / HT-1: HI (10, 90%: 10%) /

[0617] HT-1(10) / HT-2(10) / BH:BD-1(25,96%:4%) / PGH-2(10) / ET-1(12) / LiF(1) /

[0618] Al(80)

[0619] It should be noted that the numbers in parentheses represent the film thickness (unit: nm).

[0620] Within the same parentheses, when the figure is expressed as a percentage, for example, HT-1∶HI (10, 97%∶3%), it indicates that the ratio (mass%) of compound HT-1 and compound HI in the hole injection layer is HT-1∶HI = 97 mass%∶3 mass%. The same notation will be used hereafter.

[0621] (Example 2)

[0622] By varying the film thickness and material of each layer in a manner that forms the following element configuration, a bottom-emitting organic EL element was fabricated in the same manner as in Example 1.

[0623] If the component configuration of the organic EL element of Example 2 is shown in a simplified manner, it is as follows.

[0624] ITO(80) /

[0625] HT-1: HI (10, 97%: 3%) / HT-1 (10) / HT-2 (10) / BH: BD-1 (25, 96%: 4%) / PGH-3 (10) /

[0626] ET-2:Li(10,96%:4%) / HT-1:HI(10,90%:10%) /

[0627] HT-1(10) / HT-2(10) / PGH-1:PGD(48,80%:20%) / ET-1(10) /

[0628] ET-2:Li(95,96%:4%) / HT-1:HI(10,90%:10%) /

[0629] HT-1(10) / HT-2(10) / BH:BD-1(25,96%:4%) / PGH-1(10) / ET-1(10) / LiF(1) /

[0630] Al(80)

[0631] (Example 3)

[0632] By varying the film thickness and material of each layer in a manner that forms the following element configuration, a bottom-emitting organic EL element was fabricated in the same manner as in Example 1.

[0633] If the component configuration of the organic EL element of Example 3 is shown in a simplified manner, it is as follows.

[0634] ITO(130) /

[0635] HT-1: HI (10, 97%: 3%) / HT-1 (70) / HT-2 (10) / BH: BD-1 (25, 96%: 4%) / PGH-3 (10) /

[0636] ET-2:Li(10,96%:4%) / HT-1:HI(10,90%:10%) /

[0637] HT-1(10) / HT-2(10) / PGH-1:PGD(48,80%:20%) / ET-1(10) /

[0638] ET-2:Li(95,96%:4%) / HT-1:HI(10,90%:10%) /

[0639] HT-1(10) / HT-2(10) / BH:BD-1(25,96%:4%) / PGH-2(10) / ET-1(10) / LiF(1) /

[0640] Al(80)

[0641] (Example 4)

[0642] On a glass substrate (25mm × 75mm × 0.7mm thick) used for component fabrication, an APC (Ag-Pd-Cu) layer (reflective layer) with a thickness of 100nm, serving as a silver alloy layer, and an indium oxide-zinc oxide (IZO: registered trademark) film (transparent conductive layer) with a thickness of 10nm were sequentially formed by sputtering. This yielded a conductive material layer formed by the APC layer and the IZO film.

[0643] Next, using conventional photolithography techniques, the conductive material layer is patterned by etching a resist pattern through a mask to form the lower electrode (anode).

[0644] • Formation of the first light-emitting unit

[0645] Next, on the lower electrode, compounds HT-1 and HI were co-deposited using vacuum evaporation to form a hole injection layer with a thickness of 10 nm. The concentration of compound HT-1 in the hole injection layer was set to 97% by mass, and the concentration of compound HI was set to 3% by mass.

[0646] Next, compound HT-1 was deposited on the hole injection layer to form a first hole transport layer with a thickness of 10 nm.

[0647] Next, compound HT-3 was deposited on the first hole transport layer to form a second hole transport layer with a thickness of 5 nm.

[0648] Next, compounds BH and BD-2 were co-deposited on the second hole transport layer to form a blue fluorescent emissive layer with a thickness of 20 nm, serving as the first emissive layer. The concentration of compound BH in the blue fluorescent emissive layer was set to 98% by mass, and the concentration of compound BD-2 was set to 2% by mass.

[0649] Next, compound PGH-2 was deposited on the blue fluorescent emitting layer to form an electron transport layer with a thickness of 5 nm.

[0650] • Formation of the first charge generation layer

[0651] Next, compound ET-3 and lithium (Li) were co-deposited on the electron transport layer to form a first N layer with a thickness of 58 nm. The concentration of compound ET-3 in the first N layer was set to 96% by mass, and the concentration of Li was set to 4% by mass.

[0652] Next, compound HT-1 and compound HI were co-deposited on the first N layer to form a first P layer with a thickness of 10 nm. The concentration of compound HT-1 in the first P layer was set to 90% by mass, and the concentration of compound HI was set to 10% by mass.

[0653] • Formation of the second light-emitting unit

[0654] Next, compound HT-1 was deposited on the first P layer to form a first hole transport layer with a thickness of 10 nm.

[0655] Next, compound HT-3 was deposited on the first hole transport layer to form a second hole transport layer with a thickness of 5 nm.

[0656] Next, compounds BH and BD-2 were co-deposited on the second hole transport layer to form a blue emitting layer with a thickness of 20 nm, serving as the second emitting layer. The concentration of compound BH in the blue emitting layer was set to 98% by mass, and the concentration of compound BD-2 was set to 2% by mass.

[0657] Next, compound PGH-2 was deposited on the blue luminescent layer to form an electron transport layer with a thickness of 5 nm.

[0658] • Formation of the second charge generation layer

[0659] Next, compound ET-3 and lithium (Li) were co-deposited on the electron transport layer to form a second N layer with a thickness of 64 nm. The concentration of compound ET-3 in the second N layer was set to 96% by mass, and the concentration of Li was set to 4% by mass.

[0660] Next, compound HT-1 and compound HI were co-deposited on the second N layer to form a second P layer with a thickness of 10 nm. The concentration of compound HT-1 in the second P layer was set to 90% by mass, and the concentration of compound HI was set to 10% by mass.

[0661] • Formation of the third light-emitting unit

[0662] Next, compound HT-1 was deposited on the second P layer to form a first hole transport layer with a thickness of 10 nm.

[0663] Next, compound HT-3 was deposited on the first hole transport layer to form a second hole transport layer with a thickness of 5 nm.

[0664] Next, compounds BH and BD-2 were co-deposited on the second hole transport layer to form a blue fluorescent emissive layer with a thickness of 20 nm, serving as the third emissive layer. The concentration of compound BH in the blue fluorescent emissive layer was set to 98% by mass, and the concentration of compound BD-2 was set to 2% by mass.

[0665] Next, compound PGH-2 was deposited on the blue fluorescent emitting layer to form a first electron transport layer with a thickness of 5 nm.

[0666] Next, compound ET-1 was deposited on the first electron transport layer to form a second electron transport layer with a thickness of 15 nm.

[0667] Next, lithium fluoride (LiF) was deposited on the second electron transport layer to form an electron injection layer with a thickness of 1 nm.

[0668] Then, a top electrode (cathode) made of a semi-transparent MgAg alloy was formed by co-evaporation on the electron-injected layer with a Mg to Ag mixing ratio (mass % ratio) of 1:9. The total film thickness was 12 nm.

[0669] Next, a capping layer with a thickness of 70 nm was formed by depositing the compound Cap1 over the entire surface of the upper electrode.

[0670] Following the above steps, a top-emitting organic EL device was fabricated.

[0671] If the component configuration of the organic EL element of Example 4 is shown in a simplified manner, it is as follows.

[0672] APC(100) / IZO(10) /

[0673] HT-1: HI (10, 97%: 3%) / HT-1 (10) / HT-3 (5) / BH: BD-2 (20, 98%: 2%) / PGH-2 (5) /

[0674] ET-3: Li (58, 96%: 4%) / HT-1: HI (10, 90%: 10%) /

[0675] HT-1(10) / HT-3(5) / BH:BD-2(20, 98%:2%) / PGH-2(5) /

[0676] ET-3: Li (64, 96%: 4%) / HT-1: HI (10, 90%: 10%) /

[0677] HT-1(10) / HT-3(5) / BH:BD-2(20, 98%, 2%) / PGH-2(5) / ET-1(15) / LiF(1) /

[0678] Mg:Ag(12,10%:90%) / Cap1(70)

[0679] (Example 5)

[0680] By varying the film thickness and material of each layer in a manner that forms the following element configuration, a bottom-emitting organic EL element was fabricated in the same manner as in Example 1.

[0681] If the component configuration of the organic EL element of Example 5 is shown in a simplified manner, it is as follows.

[0682] ITO(130) /

[0683] HT-1:HI(10, 97%:3%) / HT-1(117) / HT-2(10) / PGH-1:PGD(40, 80%:20%) / ET-1(10) /

[0684] ET-2:Li(10,96%:4%) / HT-1:HI(10,90%:10%) /

[0685] HT-1(10) / HT-2(10) / BH:BD-1(25, 96%:4%) / PGH-2(10) /

[0686] ET-2: Li (56, 96%: 4%) / HT-1: HI (10, 90%: 10%) /

[0687] HT-1(10) / HT-2(10) / BH:BD-1(25,96%:4%) / PGH-2(10) / ET-1(70) / LiF(1) /

[0688] Al(80)

[0689] (Example 6)

[0690] By varying the film thickness and material of each layer in a manner that forms the following element configuration, a bottom-emitting organic EL element was fabricated in the same manner as in Example 1.

[0691] If the component configuration of the organic EL element of Example 6 is shown in a simplified manner, it is as follows.

[0692] ITO(130) /

[0693] HT-1: HI (10, 97%: 3%) / HT-1 (117) / HT-2 (10) / PGH-1: PRD (5, 98%: 2%, /

[0694] PGH-1:PGD(35,80%:20%) / ET-1(10) /

[0695] ET-2:Li(10,96%:4%) / HT-1:HI(10,90%:10%) /

[0696] HT-1(10) / HT-2(10) / BH:BD-3(25, 96%:4%) / PGH-2(10) /

[0697] ET-2: Li (56, 96%: 4%) / HT-1: HI (10, 90%: 10%) /

[0698] HT-1(10) / HT-2(10) / BH:BD-3(25,96%:4%) / PGH-2(10) / ET-1(12) / LiF(1) /

[0699] Al(80)

[0700] (Example 7)

[0701] By varying the film thickness and material of each layer in a manner that forms the following element configuration, a bottom-emitting organic EL element was fabricated in the same manner as in Example 1.

[0702] If the component configuration of the organic EL element of Example 7 is shown in a simplified manner, it is as follows.

[0703] ITO(80) /

[0704] HT-1: HI (10, 97%: 3%) / HT-1 (10) / HT-2 (10) / BH-2: BD-4 (25, 96%: 4%) / PGH-3 (10) /

[0705] ET-2:Li(10,96%:4%) / HT-1:HI(10,90%:10%) /

[0706] HT-1(10) / HT-2(10) / PGH-1:PRD(5,98%:2%) / PGH-1:PGD-2(43,80%:20%) / ET-1(10) /

[0707] ET-2:Li(95,96%:4%) / HT-1:HI(10,90%:10%) /

[0708] HT-1(10) / HT-2(10) / BH-2:BD-4(25,96%:4%) / PGH-1(10) / ET-1(1) / LiF(1) /

[0709] Al(80)

[0710] (Example 8)

[0711] The film thickness of each layer was varied in a manner that formed the following element configuration. Otherwise, a top-emitting organic EL element was fabricated in the same manner as in Example 4.

[0712] If the component configuration of the organic EL element of Example 8 is shown in a simplified manner, it is as follows.

[0713] APC(100) / IZO(10) /

[0714] HT-1: HI (10, 97%: 3%) / HT-1 (10) / HT-3 (5) / BH: BD-2 (20, 98%: 2%) / PGH-2 (5) /

[0715] ET-3: Li(96, 96%: 4%) / HT-1: HI (10, 90%: 10%) /

[0716] HT-1(10) / HT-3(5) / BH:BD-2(20, 98%:2%) / PGH-2(5) /

[0717] ET-3: Li (64, 96%: 4%) / HT-1: HI (10, 90%: 10%) /

[0718] HT-1(10) / HT-3(5) / BH:BD-2(20, 98%, 2%) / PGH-2(5) / ET-1(15) / LiF(1) /

[0719] Mg:Ag(12,10%:90%) / Cap1(70)

[0720] (Comparative Example 1)

[0721] By varying the film thickness and material of each layer in a manner that forms the following element configuration, a bottom-emitting organic EL element was fabricated in the same manner as in Example 1.

[0722] If the component configuration of the organic EL element of Comparative Example 1 is shown in a simplified manner, it is as follows.

[0723] ITO(130) /

[0724] HT-1:HI(10, 97%:3%) / HT-1(117) / HT-2(10) / PGH-1:PGD(40, 80%:20%) / ET-1(10) /

[0725] ET-2:Li(10,96%:4%) / HT-1:HI(10,90%:10%) /

[0726] HT-1(10) / HT-2(10) / BH:BD-1(25, 96%:4%) / PGH-2(10) /

[0727] ET-2:Li(10,96%:4%) / HT-1:HI(10,90%:10%) /

[0728] HT-1(56) / HT-2(10) / BH:BD-1(25, 96%:4%) / PGH-2(10) / ET-1(12) / LiF(1) /

[0729] Al(80)

[0730] (Comparative Example 2)

[0731] By varying the film thickness and material of each layer in a manner that forms the following element configuration, a bottom-emitting organic EL element was fabricated in the same manner as in Example 1.

[0732] If the component configuration of the organic EL element of Comparative Example 2 is shown in a simplified manner, it is as follows.

[0733] ITO(80) /

[0734] HT-1: HI (10, 97%: 3%) / HT-1 (10) / HT-2 (10) / BH: BD-1 (25, 96%: 4%) / PGH-3 (10) /

[0735] ET-2:Li(10,96%:4%) / HT-1:HI(10,90%:10%) /

[0736] HT-1(10) / HT-2(10) / PGH-1:PGD(48,80%:20%) / ET-1(10) /

[0737] ET-2:Li(10,96%:4%) / HT-1:HI(10,90%:10%) /

[0738] HT-1(95) / HT-2(10) / BH:BD-1(25, 96%:4%) / PGH-2(10) / ET-1(10) / LiF(1) /

[0739] Al(80)

[0740] (Comparative Example 3)

[0741] By varying the film thickness and material of each layer in a manner that forms the following element configuration, a bottom-emitting organic EL element was fabricated in the same manner as in Example 1.

[0742] If the component configuration of the organic EL element of Comparative Example 3 is shown in a simplified manner, it is as follows.

[0743] ITO(80) /

[0744] HT-1: HI (10, 97%: 3%) / HT-1 (10) / HT-2 (10) / BH: BD-1 (25, 96%: 4%) / PGH-3 (10) /

[0745] ET-2:Li(10,96%:4%) / HT-1:HI(10,90%:10%) /

[0746] HT-1(10) / HT-2(10) / BH:BD-1(25, 96%:4%) / ET-1(10) /

[0747] ET-2:Li(95,96%:4%) / HT-1:HI(10,90%:10%) /

[0748] HT-1(10) / HT-2(10) / PGH-1:PGD(48,80%:20%) / PGH-2(10) / ET-1(10) / LiF(1) /

[0749] Al(80)

[0750] (Comparative Example 4)

[0751] By varying the film thickness and material of each layer in a manner that forms the following element configuration, a bottom-emitting organic EL element was fabricated in the same manner as in Example 1.

[0752] If the component configuration of the organic EL element in Comparative Example 4 is shown in a simplified manner, it is as follows.

[0753] ITO(130) /

[0754] HT-1:HI(10, 97%:3%) / HT-1(117) / HT-2(10) / PGH-1:PGD(40, 80%:20%) / ET-1(10) /

[0755] ET-2:Li(10,96%:4%) / HT-1:HI(10,90%:10%) /

[0756] HT-1(10) / HT-2(10) / BH:BD-1(25, 96%:4%) / PGH-2(10) / ET-2(46) /

[0757] ET-2:Li(10,96%:4%) / HT-1:HI(10,90%:10%) /

[0758] HT-1(10) / HT-2(10) / BH:BD-1(25,96%:4%) / PGH-2(10) / ET-1(12) / LiF(1) /

[0759] Al(80)

[0760] (Comparative Example 5)

[0761] A bottom-emission type organic EL device was fabricated in the same manner as in Example 1, except that the film thickness and material of each layer were changed to form the following components, and the third light-emitting unit was not formed.

[0762] If the component structure of the organic EL device of Comparative Example 5 is shown briefly, it is as follows.

[0763] ITO(120) /

[0764] HT-1∶HI(14, 97%∶3%) / HT-1(60) / BH∶BD-1(22, 96%∶4%) / ET-1(20) /

[0765] ET-2∶Li(20, 96%∶4%) / HT-1∶HI(10, 90%∶10%) /

[0766] HT-1(30) / PGH-1∶PGD(40, 80%∶20%) / ET-1(10) /

[0767] ET-2∶Li(15, 96%∶4%) /

[0768] Al(80)

[0769] <m1 to m3, L1 to L3, and Φ1 to Φ3>

[0770] For the organic EL devices fabricated in Examples 1 to 8 and Comparative Examples 1 to 5, m1 to m3, L1 to L3, and Φ1 to Φ3 in the above mathematical formulas (1-1) to (1-3) and the above mathematical formulas (2-1) to (2-3) were determined. The results are shown in Table 1.

[0771] The main peak wavelengths of the light emitted from the blue light-emitting layer, yellow phosphorescent light-emitting layer, red-yellow phosphorescent light-emitting layer, and red-green phosphorescent light-emitting layer were measured using the method described above.

[0772] Note that the red-yellow phosphorescent light-emitting layer refers to the first light-emitting layer of Example 6 (a phosphorescent light-emitting layer formed by a red phosphorescent light-emitting layer and a yellow phosphorescent light-emitting layer). The red-green phosphorescent light-emitting layer refers to the second light-emitting layer of Example 7 (a phosphorescent light-emitting layer formed by a red phosphorescent light-emitting layer and a green phosphorescent light-emitting layer).

[0773] Φ1 is calculated using the complex refractive index N = n - jk (n: refractive index, k: extinction coefficient) of the reflective electrode (cathode in the case of Example 1), n ​​and k, and the refractive index n0 of the organic layer constituting the first light-emitting unit (first hole transport region (hole injection layer, first hole transport layer, and second hole transport layer), first light-emitting layer, and first electron transport region (electron transport layer) in the case of Example 1).

[0774] Φ2 is calculated using the complex refractive index N = n - jk (n: refractive index, k: extinction coefficient) of the reflective electrode (cathode in the case of Example 1), n ​​and k, and the refractive index n0 of the organic layer constituting the second light-emitting unit (second hole transport region (first hole transport layer and second hole transport layer), second light-emitting layer, and second electron transport region (electron transport layer) in the case of Example 1).

[0775] Φ3 is calculated using the complex refractive index N = n - jk (n: refractive index, k: extinction coefficient) of the reflective electrode (cathode in the case of Example 1), n ​​and k, and the refractive index n0 of the organic layer constituting the third light-emitting unit (third hole transport region (first hole transport layer and second hole transport layer), third light-emitting layer, and third electron transport region (first electron transport layer, second electron transport layer, and electron injection layer) in the case of Example 1).

[0776] The calculation of Φ1 to Φ3 can be performed by referring to Principles of Optics, Max Born and Emil Wolf, 1974 (PERGAMON PRESS).

[0777] Φ1 to Φ3 in Examples 2 to 8 and Comparative Examples 1 to 5 can also be calculated in the same way as above.

[0778] The refractive index of the above organic layer was measured using a spectroscopic ellipsometric apparatus.

[0779] It should be noted that the refractive index refers to the refractive index in the direction perpendicular to the surface in which the layer is formed.

[0780] Table 1

[0781]

[0782] 〔evaluate〕

[0783] The organic EL elements fabricated in Examples 1-8 and Comparative Examples 1-5 were evaluated as follows. The results are shown in Table 2.

[0784] <Main peak wavelength and peak intensity of blue fluorescence>

[0785] The main peak wavelength of blue fluorescence emitted by an organic EL element was determined using the following method. Its intensity was also measured.

[0786] With a current density reaching 10 mA / cm 2 A voltage is applied to the organic EL element, and the spectroradiance spectrum at this time is measured using a CS-2000 spectroradiometer (manufactured by Konica Minolta).

[0787] In the obtained spectroradiance spectrum, the peak wavelength and intensity of the emission spectrum at which the emission intensity reaches the maximum were measured and set as the "main peak wavelength (unit: nm)" and "main peak intensity of blue fluorescence emission" in this evaluation.

[0788] • Drive voltage

[0789] For a current density reaching 10 mA / cm 2 The voltage (in V) when current is applied between the anode and cathode is measured. The driving voltage is evaluated based on the following criteria.

[0790] -Evaluation Criteria-

[0791] A: Drive voltage less than 12V

[0792] B: Drive voltage is 12V or higher

[0793] • Lifetime of blue fluorescence

[0794] With a current density of 50 mA / cm 2 A voltage was applied to the component, and the emission spectrum was measured per unit of energization time using a CS-2000 spectroradiometer (manufactured by Konica Minolta Co., Ltd.). The emission peak intensity at 460 nm, which is the blue wavelength region, was measured. The ratio of the emission peak intensity after energization to the initial emission peak intensity was calculated. The time it took for the peak intensity to decrease by 5% relative to the initial emission peak intensity was defined as the 5% degradation lifetime (in minutes), and the 5% degradation lifetime ratio (%) was calculated using the following formula. That is, when the initial emission peak intensity is set to X, the 5% degradation lifetime refers to the time it takes for the emission peak intensity to decrease to 0.95X.

[0795] For each example of the component, the 5% degradation lifetime ratio (%) relative to Example 1 was compared.

[0796] In addition, the lifetime of blue fluorescence emitted by organic EL elements is evaluated based on the following evaluation criteria.

[0797] Calculation formula: 5% degradation lifetime ratio (%) = (5% degradation lifetime of each example / 5% degradation lifetime of Example 1) × 100

[0798] -Evaluation Criteria-

[0799] A: A 5% degradation rate results in a lifespan of over 90%.

[0800] B: 5% of the lifespan has a degradation rate of 80% or more but less than 90%.

[0801] C: 5% degradation rate is less than 80% of the lifespan.

[0802] Table 2

[0803]

[0804] (Explanation of Table 2)

[0805] ■HT region represents the hole transport region.

[0806] ■The HI layer represents the hole injection layer.

[0807] ■ HT layer 1 represents the first hole transport layer, and HT layer 2 represents the second hole transport layer.

[0808] ■ET area indicates electronic transmission area.

[0809] ■ET layer represents the electronic transport layer.

[0810] ■The thickness of the ET layer represents the total thickness when the electron transport layer is formed by multiple layers.

[0811] ■5 / 35 indicates that the stacked red phosphorescent layer is 5nm and the yellow phosphorescent layer is 35nm.

[0812] ■5 / 43 indicates that the stacked red phosphorescent layer is 5nm and the green phosphorescent layer is 43nm.

[0813] As shown in Table 2, the organic EL elements of Examples 1-8 have lower driving voltages and higher "5% degradation lifetime ratio" for blue fluorescence emission compared to the organic EL elements of Comparative Examples 1-5.

[0814] Therefore, the organic EL elements according to Examples 1 to 8 can reduce the driving voltage and increase the lifespan.

[0815] Furthermore, the organic EL elements of Examples 1-4, 6, and 7, which satisfy the optical interference formulas (specifically, mathematical formulas (1-3) and (2-3)) for the third light-emitting unit, exhibit a high main peak intensity of blue fluorescence emission. Therefore, the luminous efficiency of blue fluorescence emission can be improved according to the organic EL elements of Examples 1-4, 6, and 7.

[0816] Symbol Explanation

[0817] 1, 2... Organic EL element, 11... Substrate, 12... Anode, 13, 13A... First light-emitting unit, 14... First charge generation layer, 15, 15A... Second light-emitting unit, 16... Second charge generation layer, 17, 17A... Third light-emitting unit, 18... Cathode, 12A, 18A... Reflective interface, 131... First hole transport region, 131A, 151A, 171A... First hole transport layer, 131B, 151B, 171... B...Second hole transport layer, 131C...Hole injection layer, 132...First light-emitting layer, 133...First electron transport region, 141...First N layer, 142...First P layer, 151...Second hole transport region, 152...Second light-emitting layer, 153...Second electron transport region, 161...Second N layer, 162...Second P layer, 171...Third hole transport region, 172...Third light-emitting layer, 173...Third electron transport region.

Claims

1. An organic electroluminescent element comprising an anode, a cathode, a first light-emitting unit having a first light-emitting layer, a first charge-generating layer, a second light-emitting unit having a second light-emitting layer, a second charge-generating layer, and a third light-emitting unit having a third light-emitting layer, wherein the first light-emitting unit, the first charge-generating layer, the second light-emitting unit, the second charge-generating layer, and the third light-emitting unit are successively provided between the anode and the cathode from the anode side, the second charge-generating layer has an N layer on the anode side and a P layer on the cathode side, the third light-emitting layer contains a compound having blue fluorescent light-emitting property, at least one of the first light-emitting layer and the second light-emitting layer contains a compound having blue fluorescent light-emitting property, the third light-emitting unit further has a hole-transporting region of the third light-emitting unit between the second charge-generating layer and the third light-emitting layer, the hole-transporting region of the third light-emitting unit is in contact with the second charge-generating layer, the thickness of the hole-transporting region of the third light-emitting unit is 5 nm or more and 40 nm or less, and the thickness of the N layer is 40 nm or more.

2. The organic electroluminescent element according to claim 1, wherein one of the anode and the cathode is a reflective electrode, the organic electroluminescent element satisfies the following mathematical expression (1-3) and the following mathematical expression (2-3), n3 - 0.25 < m3 < n3 + 0.25 (1-3) in the mathematical expression (1-3), n3 is an integer of 0 or more, and m3 is an interference order between the reflective electrode and a light-emitting center of the third light-emitting layer, and in the general formula (2-3), m3 has the same meaning as m3 in the mathematical expression (1-3), L3 is an optical distance between the reflective electrode and the light-emitting center of the third light-emitting layer, λ3 is a main peak wavelength of light emission from the third light-emitting layer, and Φ3 is a phase change when the light emission from the third light-emitting layer is reflected by the reflective electrode.

3. The organic electroluminescent element according to claim 2, wherein in the general formula (1-3), n3 is an integer of 0 or more and 3 or less.

4. The organic electroluminescent element according to claim 2, wherein the organic electroluminescent element further satisfies the following mathematical expression (1-2) and the following mathematical expression (2-2), n2 - 0.25 < m2 < n2 + 0.25 (1-2) in the mathematical expression (1-2), n2 is an integer of 0 or more, and m2 is an interference order between the reflective electrode and a light-emitting center of the second light-emitting layer, and in the mathematical expression (2-2), m2 has the same meaning as m2 in the mathematical expression (1-2), L2 is an optical distance between the reflective electrode and the light-emitting center of the second light-emitting layer, λ2 is a main peak wavelength of light emission from the second light-emitting layer, and Φ2 is a phase change when the light emission from the second light-emitting layer is reflected by the reflective electrode.

5. The organic electroluminescent element according to claim 4, wherein ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ The thickness d of the N layer of the second charge generation layer N The ratio of the thickness d of the N layer of the second charge generation layer to the thickness d3 of the hole transport region of the third light emitting unit is 2 or more and 10 or less. N / The thickness d3 is 2 or more and 10 or less. ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ In the mathematical expression (1-2), n2 is an integer of 0 or more and 3 or less.

6. The organic electroluminescent device according to claim 2, wherein The organic electroluminescent device also satisfies the following mathematical expression (1-1) and the following mathematical expression (2-1), n1 - 0.25 < m1 < n1 + 0.25 (1-1) In the mathematical expression (1-1), n1 is an integer of 0 or more, and m1 is the number of interference stages between the reflective electrode and the light emission center of the first light-emitting layer, In the mathematical expression (2-1), m1 has the same meaning as m1 in the mathematical expression (1-1), L1 is the optical distance between the reflective electrode and the light emission center of the first light-emitting layer, and has a unit of nm, λ1 is the main peak wavelength of the light emission from the first light-emitting layer, and has a unit of nm, and Φ1 is the phase change when the light emission from the first light-emitting layer is reflected by the reflective electrode.

7. The organic electroluminescent device according to claim 6, wherein In the mathematical expression (1-1), n1 is an integer of 0 or more and 3 or less.

8. The organic electroluminescent device according to claim 1, wherein The main peak wavelength of the light emission from the third light-emitting layer is 430 nm or more and 500 nm or less.

9. The organic electroluminescent device according to claim 1, wherein The main peak wavelength of the light emission from the third light-emitting layer is 440 nm or more and 470 nm or less.

10. The organic electroluminescent device according to claim 1, wherein The thickness of the N layers of the second charge generation layer is 200 nm or less.

11. The organic electroluminescent device according to claim 1, wherein The thickness of the N layers of the second charge generation layer is 45 nm or more.

12. The organic electroluminescent device according to claim 1, wherein The thickness of the N layers of the second charge generation layer is 45 nm or more and 160 nm or less.

13. The organic electroluminescent device according to claim 1, wherein The thickness of the N layers of the second charge generation layer is 50 nm or more.

14. The organic electroluminescent device according to claim 1, wherein The thickness of the N layers of the second charge generation layer is 50 nm or more and 120 nm or less.

15. The organic electroluminescent device according to claim 1, wherein The hole transport region of the third light-emitting unit is formed of 2 or more layers.

16. The organic electroluminescent device according to claim 1, wherein The hole transport region of the third light-emitting unit is formed of 2 or more layers and 4 or less layers.

17. The organic electroluminescent device according to claim 1, wherein The hole transport region of the third light-emitting unit is formed of a first hole transport layer and a second hole transport layer.

18. The organic electroluminescent device according to claim 17, wherein The thickness of the first hole transport layer in the hole transport region of the third light-emitting unit is 2 nm or more and 38 nm or less, and the thickness of the second hole transport layer is 2 nm or more and 38 nm or less.

19. The organic electroluminescent device according to claim 17, wherein the thickness of the first hole-transporting layer in the hole-transporting region of the third light-emitting unit is greater than or equal to 5 nm and less than or equal to 25 nm, and the thickness of the second hole-transporting layer is greater than or equal to 5 nm and less than or equal to 25 nm.

20. The organic electroluminescent device according to claim 17, wherein the thickness of the first hole-transporting layer in the hole-transporting region of the third light-emitting unit is greater than or equal to 5 nm and less than or equal to 15 nm, and the thickness of the second hole-transporting layer is greater than or equal to 5 nm and less than or equal to 15 nm.

21. The organic electroluminescent device according to claim 17, wherein the ratio of the thickness of the second hole-transporting layer to the thickness of the first hole-transporting layer in the hole-transporting region of the third light-emitting unit is greater than or equal to 0.05 and less than or equal to 19.

22. The organic electroluminescent device according to claim 17, wherein the ratio of the thickness of the second hole-transporting layer to the thickness of the first hole-transporting layer in the hole-transporting region of the third light-emitting unit is greater than or equal to 0.2 and less than or equal to 5.

23. The organic electroluminescent device according to claim 17, wherein the ratio of the thickness of the second hole-transporting layer to the thickness of the first hole-transporting layer in the hole-transporting region of the third light-emitting unit is greater than or equal to 0.3 and less than or equal to 3.

24. The organic electroluminescent device according to claim 1, wherein the thickness of the hole-transporting region of the third light-emitting unit is greater than or equal to 10 nm and less than or equal to 30 nm.

25. The organic electroluminescent device according to claim 1, wherein the thickness of the hole-transporting region of the third light-emitting unit is greater than or equal to 15 nm and less than or equal to 25 nm.

26. The organic electroluminescent device according to claim 1, wherein the thickness of the hole-transporting region of the third light-emitting unit is greater than or equal to 15 nm and less than or equal to 20 nm.

27. The organic electroluminescent device according to claim 1, wherein The thickness d of the N layer of the second charge generation layer N The ratio of the thickness d of the N layer of the second charge generation layer to the thickness d3 of the hole transport region of the third light emitting unit is 2.5 or more and 6 or less. N The ratio of the thickness d of the N layer of the second charge generation layer to the thickness d3 of the hole transport region of the third light emitting unit is 2.5 or more and 6 or less.

28. The organic electroluminescent device according to claim 1, wherein the second light-emitting unit has a hole-transporting region of the second light-emitting unit between the first charge-generating layer and the second light-emitting layer, the hole-transporting region of the second light-emitting unit is in contact with the first charge-generating layer, the thickness of the hole-transporting region of the second light-emitting unit is greater than or equal to 5 nm and less than or equal to 40 nm.

29. The organic electroluminescent device according to claim 28, wherein the thickness of the hole-transporting region of the second light-emitting unit is greater than or equal to 10 nm and less than or equal to 30 nm.

30. The organic electroluminescent device according to claim 28, wherein the thickness of the hole-transporting region of the second light-emitting unit is greater than or equal to 15 nm and less than or equal to 25 nm.

31. The organic electroluminescent device according to claim 28, wherein the hole-transporting region of the second light-emitting unit is formed of two or more layers.

32. The organic electroluminescent device according to claim 28, wherein the hole-transporting region of the second light-emitting unit is formed of two or more layers and less than or equal to four layers.

33. The organic electroluminescent device according to claim 28, wherein the hole-transporting region of the second light-emitting unit is formed of a first hole-transporting layer and a second hole-transporting layer.

34. The organic electroluminescent device according to claim 33, wherein the thickness of the first hole-transporting layer in the hole-transporting region of the second light-emitting unit is 2 nm or more and 38 nm or less, and the thickness of the second hole-transporting layer is 2 nm or more and 38 nm or less.

35. The organic electroluminescent device according to claim 33, wherein the thickness of the first hole-transporting layer in the hole-transporting region of the second light-emitting unit is 5 nm or more and 25 nm or less, and the thickness of the second hole-transporting layer is 5 nm or more and 25 nm or less.

36. The organic electroluminescent device according to claim 33, wherein the thickness of the first hole-transporting layer in the hole-transporting region of the second light-emitting unit is 5 nm or more and 15 nm or less, and the thickness of the second hole-transporting layer is 5 nm or more and 15 nm or less.

37. The organic electroluminescent device according to claim 33, wherein the ratio of the thickness of the second hole-transporting layer to the thickness of the first hole-transporting layer in the hole-transporting region of the second light-emitting unit is 0.05 or more and 19 or less.

38. The organic electroluminescent device according to claim 33, wherein the ratio of the thickness of the second hole-transporting layer to the thickness of the first hole-transporting layer in the hole-transporting region of the second light-emitting unit is 0.2 or more and 5 or less.

39. The organic electroluminescent device according to claim 33, wherein the ratio of the thickness of the second hole-transporting layer to the thickness of the first hole-transporting layer in the hole-transporting region of the second light-emitting unit is 0.3 or more and 3 or less.

40. The organic electroluminescent device according to claim 1, wherein the second light-emitting layer comprises a compound having blue fluorescent light-emitting property.

41. The organic electroluminescent device according to claim 40, wherein the main peak wavelength of the light emission from the second light-emitting layer is 430 nm or more and 500 nm or less.

42. The organic electroluminescent device according to claim 40, wherein the main peak wavelength of the light emission from the second light-emitting layer is 440 nm or more and 470 nm or less.

43. The organic electroluminescent device according to claim 1, wherein the second light-emitting layer is a yellow fluorescent light-emitting layer.

44. The organic electroluminescent device according to claim 1, wherein the second light-emitting layer is a red fluorescent light-emitting layer.

45. The organic electroluminescent device according to claim 1, wherein the second light-emitting layer is a green fluorescent light-emitting layer.

46. The organic electroluminescent device according to claim 1, wherein the first light-emitting unit has a hole-transporting region of the first light-emitting unit between the anode and the first light-emitting layer, the hole-transporting region of the first light-emitting unit is in contact with the anode, the hole-transporting region of the first light-emitting unit is in contact with the first light-emitting layer, The thickness of the hole-transporting region of the first light-emitting unit is greater than or equal to 5 nm and less than or equal to 40 nm.

47. The organic electroluminescent device according to claim 46, wherein The hole-transporting region of the first light-emitting unit is formed of three or more layers.

48. The organic electroluminescent device according to claim 46, wherein The thickness of the hole-transporting region of the first light-emitting unit is greater than or equal to 10 nm and less than or equal to 30 nm.

49. The organic electroluminescent device according to claim 46, wherein The thickness of the hole-transporting region of the first light-emitting unit is greater than or equal to 15 nm and less than or equal to 25 nm.

50. The organic electroluminescent device according to claim 1, wherein The first light-emitting layer contains a compound having blue fluorescent light-emitting property.

51. The organic electroluminescent device according to claim 1, wherein The first light-emitting layer is a yellow fluorescent light-emitting layer.

52. The organic electroluminescent device according to claim 1, wherein The first light-emitting layer is a red fluorescent light-emitting layer.

53. The organic electroluminescent device according to claim 1, wherein The first light-emitting layer is a green fluorescent light-emitting layer.

54. The organic electroluminescent device according to claim 1, wherein The first light-emitting layer and the third light-emitting layer are blue fluorescent light-emitting layers.

55. The organic electroluminescent device according to claim 1, wherein The second light-emitting layer and the third light-emitting layer are blue fluorescent light-emitting layers.

56. The organic electroluminescent device according to claim 1, wherein The first light-emitting layer, the second light-emitting layer, and the third light-emitting layer are all blue fluorescent light-emitting layers.

57. The organic electroluminescent device according to claim 1, wherein The first light-emitting layer is a yellow phosphorescent light-emitting layer, the second light-emitting layer is a blue fluorescent light-emitting layer, and the third light-emitting layer is a blue fluorescent light-emitting layer.

58. The organic electroluminescent device according to claim 1, wherein The first light-emitting layer is a blue fluorescent light-emitting layer, the second light-emitting layer is a yellow phosphorescent light-emitting layer, and the third light-emitting layer is a blue fluorescent light-emitting layer.

59. The organic electroluminescent device according to claim 1, wherein The first light-emitting layer is a red-yellow phosphorescent light-emitting layer, the second light-emitting layer is a blue fluorescent light-emitting layer, and the third light-emitting layer is a blue fluorescent light-emitting layer.

60. The organic electroluminescent device according to claim 1, wherein The first light-emitting layer is a blue fluorescent light-emitting layer, the second light-emitting layer is a red-green phosphorescent light-emitting layer, and the third light-emitting layer is a blue fluorescent light-emitting layer.

61. The organic electroluminescent device according to claim 50, wherein The main peak wavelength of the light emission from the first light-emitting layer is greater than or equal to 430 nm and less than or equal to 500 nm.

62. The organic electroluminescent device according to claim 50, wherein The main peak wavelength of the light emission from the first light-emitting layer is greater than or equal to 440 nm and less than or equal to 470 nm.

63. The organic electroluminescent device according to claim 46, wherein The hole-transporting region of the first light-emitting unit is formed of three layers.

64. The organic electroluminescent device according to claim 46, wherein the hole-transporting region of the first light-emitting unit is formed of 3 or more and 5 or less layers.

65. The organic electroluminescent device according to claim 46, wherein the hole-transporting region of the first light-emitting unit comprises, in order from the anode side, a hole-injection layer, a first hole-transporting layer, and a second hole-transporting layer.

66. The organic electroluminescent device according to claim 65, wherein the thickness of the first hole-transporting layer in the hole-transporting region of the first light-emitting unit is 2 nm or more and 38 nm or less, and the thickness of the second hole-transporting layer is 2 nm or more and 38 nm or less.

67. The organic electroluminescent device according to claim 65, wherein the thickness of the first hole-transporting layer in the hole-transporting region of the first light-emitting unit is 5 nm or more and 25 nm or less, and the thickness of the second hole-transporting layer is 5 nm or more and 25 nm or less.

68. The organic electroluminescent device according to claim 65, wherein the thickness of the first hole-transporting layer in the hole-transporting region of the first light-emitting unit is 5 nm or more and 15 nm or less, and the thickness of the second hole-transporting layer is 5 nm or more and 15 nm or less.

69. The organic electroluminescent device according to claim 65, wherein the ratio of the thickness of the second hole-transporting layer to the thickness of the first hole-transporting layer in the hole-transporting region of the first light-emitting unit is 0.05 or more and 19 or less.

70. The organic electroluminescent device according to claim 65, wherein the ratio of the thickness of the second hole-transporting layer to the thickness of the first hole-transporting layer in the hole-transporting region of the first light-emitting unit is 0.2 or more and 5 or less.

71. The organic electroluminescent device according to claim 65, wherein the ratio of the thickness of the second hole-transporting layer to the thickness of the first hole-transporting layer in the hole-transporting region of the first light-emitting unit is 0.3 or more and 3 or less.

72. The organic electroluminescent device according to claim 1, wherein the first light-emitting layer comprises a host material and a dopant material, the second light-emitting layer comprises a host material and a dopant material, the third light-emitting layer comprises a host material and a dopant material.

73. The organic electroluminescent device according to claim 72, wherein the host material is selected from the group consisting of an amine derivative, an azine derivative, and a fused polycyclic aromatic derivative, the amine derivative is selected from the group consisting of a monoamine compound, a diamine compound, a triamine compound, a tetraamine compound, and a carbazolyl-substituted amine compound, the azine derivative is selected from the group consisting of a monoxazine derivative, a diazine derivative, and a triazine derivative, the fused polycyclic aromatic derivative is a fused polycyclic aromatic hydrocarbon having no heterocyclic skeleton.

74. The organic electroluminescent device according to claim 72, wherein the host material is an anthracene derivative represented by the following general formula (11), In the general formula (11), R 101 ~R 110 each independently is a hydrogen atom or a substituent, and R 101 ~R 110 each independently is a substituted or unsubstituted alkyl group with a carbon number of 1 to 30, a substituted or unsubstituted alkenyl group with a carbon number of 2 to 30, a substituted or unsubstituted alkynyl group with a carbon number of 2 to 30, a substituted or unsubstituted aryl group with a carbon number of 6 to 13, a substituted or unsubstituted cycloalkyl group having 3 to 30 ring-forming carbon atoms, a substituted or unsubstituted alkoxy group having 1 to 30 carbon atoms, a substituted or unsubstituted alkylthio group having 1 to 50 carbon atoms, a substituted or unsubstituted aryloxy group having 6 to 30 ring-forming carbon atoms, a substituted or unsubstituted arylthio group having 6 to 30 ring-forming carbon atoms, a substituted or unsubstituted aralkyl group having 7 to 30 carbon atoms, -Si(R 121 )(R 122 )(R 123 ), - C(=O)R 124 , - COOR 125 , -N(R 126 )(R 127 ), a halogen atom, a cyano group, a nitro group, a substituted or unsubstituted aryl group having 6 to 30 ring-forming carbon atoms, a substituted or unsubstituted heterocyclic group having 5 to 30 ring-forming atoms, or - L 101 - Ar 101 the groups shown, R 101 ~R 110 when 2 or more substituents adjacent to each other are optionally bonded to form a saturated or unsaturated ring, R 121 ~R 127 each independently is a hydrogen atom, or a substituent, R 121 ~R 127 each independently is a substituted or unsubstituted alkyl group having 1 to 30 carbon atoms, a substituted or unsubstituted aryl group having 6 to 30 ring-forming carbon atoms, or a substituted or unsubstituted heterocyclic group having 5 to 30 ring-forming atoms, R 101 ~R 110 at least one of R 101 -Ar 101 the groups shown in the formulae L 101 is a single bond, or a linking group, L as a linking group 101 substituted or unsubstituted arylene having 6 to 30 ring-forming carbons, or a substituted or unsubstituted heteroarylene having 5 to 30 ring-forming atoms, Ar 101 substituted or unsubstituted aryl having 6 to 30 ring-forming carbons, or a substituted or unsubstituted heterocyclic group having 5 to 30 ring-forming atoms, In L 101 When two or more exist, the two or more L 101 are the same or different from each other, in Ar 101 When two or more exist, the two or more Ar 101 are the same or different from each other, in R 121 When two or more exist, the two or more R 121 are the same or different from each other, in R 122 When two or more exist, the two or more R 122 are the same or different from each other, in R 123 When two or more exist, the two or more R 123 are the same or different from each other, in R 124 When two or more exist, the two or more R 124 are the same or different from each other, in R 125 When two or more exist, the two or more R 125 are the same or different from each other, in R 126 When two or more exist, the two or more R 126 are the same or different from each other, in R 127 When two or more exist, the two or more R 127 are the same or different from each other.

75. The organic electroluminescent device according to claim 74, wherein In the general formula (11), R 101 ~R 110 each independently is a hydrogen atom, a substituted or unsubstituted alkyl group having a carbon number of 1 to 30, a substituted or unsubstituted aryl group having a ring-constituting carbon number of 6 to 30, a substituted or unsubstituted heterocyclic group having a ring-constituting atom number of 5 to 30, or a group represented by 101 -Ar 101 .

76. The organic electroluminescent device according to claim 74, wherein In the general formula (11), R 101 ~R 110 each independently is a hydrogen atom, a substituted or unsubstituted aryl group having 6 to 30 ring-forming carbon atoms, a substituted or unsubstituted heterocyclic group having 5 to 30 ring-forming atoms, or a group of -L 101 -Ar 101 indicated.

77. The organic electroluminescent device according to claim 74, wherein In the general formula (11), R 101 ~R 110 each independently is a group represented by -L 109 and R 110 each independently is a group represented by -Ar 101 -Ar 101 .

78. The organic electroluminescent device according to claim 74, wherein In the general formula (11), R 109 and R 110 At least one of them is -L 101 -Ar 101 The group shown.

79. The organic electroluminescent device according to claim 74, wherein In the general formula (11), Ar 101 - Ar 101 in the group represented by -L 101 is an aryl group, Ar 101 is a substituted or unsubstituted phenyl group, or a substituted or unsubstituted naphthyl group.

80. The organic electroluminescent device according to claim 74, wherein In the general formula (11), Ar 101 - Ar 101 in the group represented by 101 In the case where Ar 101 is a substituted or unsubstituted dibenzofuranyl group, a substituted or unsubstituted dibenzothiophenyl group, a substituted or unsubstituted naphthobenzofuranyl group, or a substituted or unsubstituted naphthobenzothiophenyl group.

81. The organic electroluminescent device according to claim 74, wherein the compound represented by General Formula (11) is any one of the following compounds, 。 82. The organic electroluminescent device according to claim 72, wherein when the first light-emitting layer or the second light-emitting layer is a phosphorescent light-emitting layer, a host material included in the phosphorescent light-emitting layer is selected from the group consisting of a carbazole derivative, a triazole derivative, an oxazole derivative, an oxadiazole derivative, an imidazole derivative, a polyarylalkane derivative, a pyrazoline derivative, a pyrazoline ketone derivative, a phenylenediamine derivative, an arylamine derivative, an amino-substituted chalcone derivative, a styrylanthracene derivative, a fluorenone derivative, a hydrazone derivative, a stilbene derivative, a silazane derivative, an aromatic tertiary amine compound, a styrylamine compound, an aromatic dimethylidene compound, a porphyrin compound, an anthraquinone dimethane derivative, an anthrone derivative, a diphenylquinone derivative, a thiopyran dioxide derivative, a carbodiimide derivative, a fluorenylidene methane derivative, a diphenylstyrylpyrazine derivative, a tetracarboxylic anhydride, a phthalocyanine derivative, a metal complex of an 8-hydroxyquinoline derivative, a metal phthalocyanine, a metal complex having a benzoxazole or benzothiazole as a ligand, a polysilane compound, a poly(N-vinylcarbazole) derivative, an aniline-based copolymer, a thiophene oligomer, a polythiophene, a polythiophene derivative, a polystyryl derivative, a polystyryl derivative, and a polyfluorene derivative.

83. The organic electroluminescent device according to claim 72, wherein the content of the host material included in the first light-emitting layer is 80 mass% or more and 99.9 mass% or less with respect to the entire first light-emitting layer, the content of the host material included in the second light-emitting layer is 80 mass% or more and 99.9 mass% or less with respect to the entire second light-emitting layer, The content of the host material included in the third light-emitting layer is 80% by mass or more and 99.9% by mass or less with respect to the entire third light-emitting layer.

84. The organic electroluminescent device according to claim 72, wherein The content of the host material included in the first light-emitting layer is 90% by mass or more and 99.9% by mass or less with respect to the entire first light-emitting layer, The content of the host material included in the second light-emitting layer is 90% by mass or more and 99.9% by mass or less with respect to the entire second light-emitting layer, The content of the host material included in the third light-emitting layer is 90% by mass or more and 99.9% by mass or less with respect to the entire third light-emitting layer.

85. The organic electroluminescent device according to claim 72, wherein The content of the host material included in the first light-emitting layer is 95% by mass or more and 99.9% by mass or less with respect to the entire first light-emitting layer, The content of the host material included in the second light-emitting layer is 95% by mass or more and 99.9% by mass or less with respect to the entire second light-emitting layer, The content of the host material included in the third light-emitting layer is 95% by mass or more and 99.9% by mass or less with respect to the entire third light-emitting layer.

86. The organic electroluminescent device according to claim 72, wherein when the third light-emitting layer, and at least one of the first light-emitting layer and the second light-emitting layer is a blue fluorescent light-emitting layer, a blue-series fluorescent light-emitting material is included as a dopant material, the blue-series fluorescent light-emitting material is selected from styrylamine derivatives, chrysenyl derivatives, fluoranthenyl derivatives, fluorenyl derivatives, monoamine derivatives, diamine derivatives, and triarylamine derivatives.

87. The organic electroluminescent device according to claim 86, wherein the first light-emitting layer or the second light-emitting layer is a light-emitting layer other than a blue fluorescent light-emitting layer.

88. The organic electroluminescent device according to claim 87, wherein when the first light-emitting layer or the second light-emitting layer is a light-emitting layer other than a blue fluorescent light-emitting layer, the first light-emitting layer or the second light-emitting layer includes a fluorescent light-emitting material other than a blue-series fluorescent light-emitting material or a phosphorescent light-emitting material, the fluorescent light-emitting material other than a blue-series fluorescent light-emitting material is selected from: a red-series fluorescent light-emitting material selected from naphthacene derivatives and diamine derivatives; a green-series fluorescent light-emitting material that is an aromatic amine derivative; a yellow-series fluorescent light-emitting material selected from anthracene derivatives and fluoranthenyl derivatives; the phosphorescent light-emitting material is selected from: a blue-series phosphorescent light-emitting material selected from iridium complexes, osmium complexes, and platinum complexes; a green-series phosphorescent light-emitting material that is an iridium complex; a red-series phosphorescent light-emitting material selected from iridium complexes, platinum complexes, terbium complexes, and europium complexes; and a yellow-series phosphorescent light-emitting material that is an iridium complex.

89. The organic electroluminescent device according to claim 86, wherein the blue-series fluorescent light-emitting material used in the blue fluorescent light-emitting layer is a monoamine derivative or a diamine derivative represented by the following general formula (1), in the general formula (1), A represents a substituted or unsubstituted aryl group having a ring-forming carbon number of 10 to 40, or a substituted or unsubstituted aryl group having a ring-forming carbon number of 10 to 40, or a substituted or unsubstituted heteroaryl group having 5 to 12 ring-forming carbon atoms, L1and L2each independently represent a single bond, a substituted or unsubstituted aryl group having 6 to 12 ring-forming carbon atoms, or a substituted or unsubstituted heteroaryl group having 5 to 12 ring-forming carbon atoms, Ar1and Ar2each independently represent a substituted or unsubstituted aryl group having 6 to 25 ring-forming carbon atoms, or a substituted or unsubstituted heteroaryl group having 3 to 25 ring-forming carbon atoms, n is 1 or 2, as a substituent when substituted, represents a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted aryl group having 6 to 25 ring-forming carbon atoms, a substituted or unsubstituted aralkyl group having 7 to 25 ring-forming carbon atoms, a substituted or unsubstituted cycloalkyl group having 3 to 25 ring-forming carbon atoms, a substituted or unsubstituted alkoxy group having 3 to 20 carbon atoms, a substituted or unsubstituted aryloxy group having 6 to 25 ring-forming carbon atoms, a substituted or unsubstituted arylamino group having 6 to 20 ring-forming carbon atoms, a fluorine atom, a substituted or unsubstituted alkylamino group having 1 to 20 carbon atoms, or a cyano group.

90. The organic electroluminescent device according to claim 89, wherein the monoamine derivative or the diamine derivative represented by General Formula (1) is any one of the following compounds, 。 91. The organic electroluminescent device according to claim 1, wherein the compound having blue fluorescent emission included in the third light-emitting layer is a compound represented by General Formula (D2) below, in General Formula (D2), ring α, ring β, and ring γ are each independently selected from the group consisting of a substituted or unsubstituted aromatic hydrocarbon ring having 6 to 30 ring-forming carbon atoms, and a substituted or unsubstituted aromatic heterocycle having 5 to 30 ring-forming atoms, R a and R b each independently is selected from the group consisting of a substituted or unsubstituted aryl group having 6 to 30 ring-forming carbon atoms, a substituted or unsubstituted heteroaryl group having 5 to 30 ring-forming atoms, and a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, R a optionally bonded directly or via a linking group to one or both of ring alpha and ring beta, R b optionally bonded directly or via a linking group to one or both of ring alpha and ring gamma.

92. The organic electroluminescent device according to claim 91, wherein the compound having blue fluorescent emission included in at least one of the first light-emitting layer and the second light-emitting layer is a compound represented by General Formula (D2).

93. The organic electroluminescent device according to claim 91, wherein in General Formula (D2), the aromatic hydrocarbon ring has 6 to 24 ring-forming carbon atoms.

94. The organic electroluminescent device according to claim 91, wherein in General Formula (D2), the aromatic hydrocarbon ring has 6 to 18 ring-forming carbon atoms.

95. The organic electroluminescent device according to claim 91, wherein in General Formula (D2), the aromatic hydrocarbon ring is selected from the group consisting of a benzene ring, a biphenyl ring, a naphthalene ring, a terphenyl ring, an anthracene ring, an acenaphthylene ring, a fluorene ring, a phenalene ring, a phenanthrene ring, a triphenylene ring, a fluoranthene ring, a pyrene ring, a naphthacene ring, a perylene ring, and a pentacene ring.

96. The organic electroluminescent device according to claim 91, wherein in General Formula (D2), the aromatic heterocycle has 5 to 18 ring-forming atoms.

97. The organic electroluminescent device according to claim 91, wherein in General Formula (D2), the aromatic heterocycle has 5 to 13 ring-forming atoms.

98. The organic electroluminescent device according to claim 91, wherein the aromatic heterocyclic ring in the general formula (D2) is selected from the group consisting of a pyrrole ring, an oxazole ring, an isoxazole ring, a thiazole ring, an isothiazole ring, an imidazole ring, an oxadiazole ring, a thiadiazole ring, a triazole ring, a tetrazole ring, a pyrazole ring, a pyridine ring, a pyrimidine ring, a pyridazine ring, a pyrazine ring, a triazine ring, an indole ring, an isoindole ring, a lH-indazole ring, a benzimidazole ring, a benzoxazole ring, a benzothiazole ring, a lH-benzotriazole ring, a quinoline ring, an isoquinoline ring, a cinnoline ring, a quinazoline ring, a quinoxaline ring, a phthalazine ring, a naphthyridine ring, a purine ring, a pteridine ring, a carbazole ring, an acridine ring, a phenoxathiine ring, a phenoxazine ring, a phenothiazine ring, a phenoxazine ring, an indolizine ring, a furan ring, a benzofuran ring, an isobenzofuran ring, a dibenzofuran ring, a thiophene ring, a benzothiophene ring, a dibenzothiophene ring, a furazan ring, and a thianthrene ring.

99. The organic electroluminescent device according to claim 91, wherein the ring α, the ring β, and the ring γ in the general formula (D2) are each independently a five-membered ring or a six-membered ring.

100. The organic electroluminescent device according to claim 91, wherein the substituents D in the expression "substituted or unsubstituted" in the ring α, the ring β, and the ring γ in the general formula (D2) are each independently at least one selected from the group consisting of a substituted or unsubstituted aryl group having a ring-constituting carbon number of 6 to 30, a substituted or unsubstituted heteroaryl group having a ring-constituting atom number of 5 to 30, a diarylamino group, a diheteroarylamino group, or an arylheteroarylamino group substituted with at least one selected from the group consisting of a substituted or unsubstituted aryl group having a ring-constituting carbon number of 6 to 30 and a substituted or unsubstituted heteroaryl group having a ring-constituting atom number of 5 to 30, a substituted or unsubstituted alkyl group having a carbon number of 1 to 20, a substituted or unsubstituted alkoxy group having a carbon number of 1 to 20, and a substituted or unsubstituted aryloxy group having a carbon number of 6 to 30.

101. The organic electroluminescent device according to claim 100, wherein the substituents D in the expression "substituted or unsubstituted" in the ring α, the ring β, and the ring γ in the general formula (D2) are each independently at least one selected from the group consisting of a substituted or unsubstituted aryl group having a ring-constituting carbon number of 6 to 24, a substituted or unsubstituted heteroaryl group having a ring-constituting atom number of 5 to 18, a diarylamino group, a diheteroarylamino group, or an arylheteroarylamino group substituted with at least one selected from the group consisting of a substituted or unsubstituted aryl group having a ring-constituting carbon number of 6 to 24 and a substituted or unsubstituted heteroaryl group having a ring-constituting atom number of 5 to 18, a substituted or unsubstituted alkyl group having a carbon number of 1 to 10, a substituted or unsubstituted alkoxy group having a carbon number of 1 to 10, and a substituted or unsubstituted aryloxy group having a carbon number of 6 to 24.

102. The organic electroluminescent device according to claim 100, wherein the substituents D in the expression "substituted or unsubstituted" in the ring α, the ring β, and the ring γ in the general formula (D2) are each independently at least one selected from the group consisting of a substituted or unsubstituted aryl group having a ring-constituting carbon number of 6 to 18, a substituted or unsubstituted heteroaryl group having a ring-constituting atom number of 5 to 13, a substituted or unsubstituted alkyl group having a carbon number of 1 to 10, a substituted or unsubstituted alkoxy group having a carbon number of 1 to 10, and a substituted or unsubstituted aryloxy group having a carbon number of 6 to 18. at least one group selected from the group consisting of a substituted or unsubstituted aryl group having 6 to 18 ring-forming carbon atoms, and a substituted or unsubstituted heteroaryl group having 5 to 13 ring-forming atoms, a substituted or unsubstituted alkyl group having 1 to 6 carbon atoms, a substituted or unsubstituted alkoxy group having 1 to 6 carbon atoms, and a substituted or unsubstituted aryloxy group having 6 to 18 carbon atoms.

103. The organic electroluminescent device according to claim 100, wherein when the substituent D further has a substituent E, the substituent E is each independently at least one selected from the group consisting of a substituted or unsubstituted aryl group having 6 to 30 ring-forming carbon atoms, a substituted or unsubstituted heteroaryl group having 5 to 30 ring-forming atoms, and a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms.

104. The organic electroluminescent device according to claim 100, wherein when the substituent D further has a substituent E in the general formula (D2), the substituent E is each independently at least one selected from the group consisting of a substituted or unsubstituted aryl group having 6 to 24 ring-forming carbon atoms, a substituted or unsubstituted heteroaryl group having 5 to 18 ring-forming atoms, and a substituted or unsubstituted alkyl group having 1 to 10 carbon atoms.

105. The organic electroluminescent device according to claim 100, wherein when the substituent D further has a substituent E in the general formula (D2), the substituent E is each independently at least one selected from the group consisting of a substituted or unsubstituted aryl group having 6 to 18 ring-forming carbon atoms, a substituted or unsubstituted heteroaryl group having 5 to 13 ring-forming atoms, and a substituted or unsubstituted alkyl group having 1 to 6 carbon atoms.

106. The organic electroluminescent device according to claim 91, wherein when two substituents adjacent to each other on the ring α, the ring β, and the ring γ in the general formula (D2) are bonded to each other to form a ring, the ring is a substituted or unsubstituted aromatic hydrocarbon ring having 6 to 30 ring-forming carbon atoms, or a substituted or unsubstituted aromatic heterocyclic ring having 5 to 30 ring-forming atoms.

107. The organic electroluminescent device according to claim 91, wherein when two substituents adjacent to each other on the ring α, the ring β, and the ring γ in the general formula (D2) are bonded to each other to form a ring, the ring is a substituted or unsubstituted aromatic hydrocarbon ring having 6 to 24 ring-forming carbon atoms, or a substituted or unsubstituted aromatic heterocyclic ring having 5 to 18 ring-forming atoms.

108. The organic electroluminescent device according to claim 91, wherein when two substituents D adjacent to each other on the ring α, the ring β, and the ring γ in the general formula (D2) are bonded to each other to form a ring, the ring is a substituted or unsubstituted aromatic hydrocarbon ring having 6 to 18 ring-forming carbon atoms, or a substituted or unsubstituted aromatic heterocyclic ring having 5 to 13 ring-forming atoms.

109. The organic electroluminescent device according to claim 91, wherein In the general formula (D2), R a and R b each independently is selected from the group consisting of a substituted or unsubstituted aryl group having 6 to 24 ring-forming carbon atoms, a substituted or unsubstituted heteroaryl group having 5 to 18 ring-forming atoms, and a substituted or unsubstituted alkyl group having 1 to 10 carbon atoms.

110. The organic electroluminescent device according to claim 91, wherein In the general formula (D2), R a and R b each independently is selected from the group consisting of a substituted or unsubstituted aryl group having 6 to 18 ring-forming carbon atoms, a substituted or unsubstituted heteroaryl group having 5 to 13 ring-forming atoms, and a substituted or unsubstituted alkyl group having 1 to 6 carbon atoms.

111. The organic electroluminescent device according to claim 91, wherein in General Formula (D2), the linking group is - O-, -S-, or -CR c R d -, R c and R d each independently is a hydrogen atom, or a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, the number of carbon atoms in the substituted or unsubstituted alkyl group having 1 to 20 carbon atoms is 1 to 10.

112. The organic electroluminescent device according to claim 91, wherein in General Formula (D2), the linking group is - O-, -S-, or -CR c R d -, R c and R d each independently is a hydrogen atom, or a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, the number of carbon atoms in the substituted or unsubstituted alkyl group having 1 to 20 carbon atoms is 1 to 6.

113. The organic electroluminescent device according to claim 86, wherein the dopant material used in the blue fluorescent light-emitting layer is a compound represented by General Formula (D3), in General Formula (D3), R 11 ~R 20 and R a1 ~R a10 Each is independently a hydrogen atom or a substituent, wherein R 11 and R 12 group, R 12 and R 13 group, R 13 and R 14 group, R 14 and R 15 group, R 15 and R 16 group, R 17 and R 18 Group, R 18 and R 19 group, R 19 and R 20 group, R a1 and R a2 group, R a2 and R a3 group, R a3 and R a4 group, R a4 and R a5 group, R a6 and R a7 group, R a7 and R a8 group, R a8 and R a9 The group, and R a9 and R a10 One or more groups in the group bond with each other to form a saturated or unsaturated ring with 3 to 30 substituted or unsubstituted cyclic atoms. R as a substituent 11 ~R 20 , and R a1 ~R a10 each independently is selected from the group consisting of a substituted or unsubstituted alkyl group having 1 to 30 carbon atoms, a substituted or unsubstituted cycloalkyl group having 3 to 30 ring-forming carbon atoms, a substituted or unsubstituted alkyl group having 1 to 30 carbon atoms, a substituted or unsubstituted alkylthio group having 1 to 30 carbon atoms, a substituted or unsubstituted amino group, a substituted or unsubstituted aryl group having 6 to 30 ring-forming carbon atoms, a substituted or unsubstituted heterocyclic group having 5 to 30 ring-forming atoms, a substituted or unsubstituted alkenyl group having 2 to 30 carbon atoms, a substituted or unsubstituted aryloxy group having 6 to 30 ring-forming carbon atoms, a substituted or unsubstituted arylthio group having 6 to 30 ring-forming carbon atoms, a substituted or unsubstituted phosphino group, a substituted or unsubstituted phosphoryl group, a substituted or unsubstituted silyl group, a substituted or unsubstituted arylcarbonyl group having 6 to 30 ring-forming carbon atoms, a cyano group, a nitro group, a carboxyl group, and a halogen atom.

114. The organic electroluminescent device according to claim 72, wherein the content of the dopant material contained in the first light-emitting layer is 0.1 mass% or more and 20 mass% or less with respect to the entire first light-emitting layer, the content of the dopant material contained in the second light-emitting layer is 0.1 mass% or more and 20 mass% or less with respect to the entire second light-emitting layer, the content of the dopant material contained in the third light-emitting layer is 0.1 mass% or more and 20 mass% or less with respect to the entire third light-emitting layer.

115. The organic electroluminescent device according to claim 72, wherein the content of the dopant material contained in the first light-emitting layer is 0.1 mass% or more and 10 mass% or less with respect to the entire first light-emitting layer, the content of the dopant material contained in the second light-emitting layer is 0.1 mass% or more and 10 mass% or less with respect to the entire second light-emitting layer, the content of the dopant material contained in the third light-emitting layer is 0.1 mass% or more and 10 mass% or less with respect to the entire third light-emitting layer.

116. The organic electroluminescent device according to claim 72, wherein the content of the dopant material included in the first light-emitting layer is 0.1 mass% or more and 5 mass% or less with respect to the entire first light-emitting layer, the content of the dopant material included in the second light-emitting layer is 0.1 mass% or more and 5 mass% or less with respect to the entire second light-emitting layer, the content of the dopant material included in the third light-emitting layer is 0.1 mass% or more and 5 mass% or less with respect to the entire third light-emitting layer.

117. The organic electroluminescent device according to claim 1, wherein the thickness of the first light-emitting layer is 5 nm or more and 100 nm or less, the thickness of the second light-emitting layer is 5 nm or more and 100 nm or less, the thickness of the third light-emitting layer is 5 nm or more and 100 nm or less.

118. The organic electroluminescent device according to claim 1, wherein the thickness of the first light-emitting layer is 10 nm or more and 80 nm or less, the thickness of the second light-emitting layer is 10 nm or more and 80 nm or less, the thickness of the third light-emitting layer is 10 nm or more and 80 nm or less.

119. The organic electroluminescent device according to claim 1, wherein the thickness of the first light-emitting layer is 15 nm or more and 60 nm or less, the thickness of the second light-emitting layer is 15 nm or more and 60 nm or less, the thickness of the third light-emitting layer is 15 nm or more and 60 nm or less.

120. The organic electroluminescent device according to claim 1, wherein the second charge generation layer has a second N layer as the N layer on the anode side and a second P layer as the P layer on the cathode side, the second N layer includes a π-electron deficient compound and an electron-donating material, the second P layer is a layer including an acceptor material.

121. The organic electroluminescent device according to claim 120, wherein the second P layer is a layer doped with an acceptor material.

122. The organic electroluminescent device according to claim 1, wherein the first charge generation layer includes a first N layer on the anode side and a first P layer on the cathode side, the first N layer includes a π-electron deficient compound and an electron-donating material, the first P layer is a layer including an acceptor material.

123. The organic electroluminescent device according to claim 122, wherein the first P layer is a layer doped with an acceptor material.

124. The organic electroluminescent device according to claim 1, wherein the third light-emitting unit further has a third electron transport region of the third light-emitting unit between the cathode and the third light-emitting layer, the thickness of the third electron transport region is 5 nm or more and 100 nm or less.

125. The organic electroluminescent device according to claim 1, wherein the second light-emitting unit further has a second electron transport region of the second light-emitting unit between the cathode and the second light-emitting layer, the thickness of the second electron transport region is 5 nm or more and 100 nm or less.

126. The organic electroluminescent device according to claim 1, wherein The first light-emitting unit further has a first electron transport region of the first light-emitting unit between the cathode and the first light-emitting layer, The thickness of the first electron transport region is 5 nm or more and 100 nm or less.

127. The organic electroluminescent device according to claim 1, wherein One of the anode and the cathode is a reflective electrode, The organic electroluminescent device satisfies the following mathematical expression (1-3) and the following mathematical expression (2-3), The organic electroluminescent device satisfies the following mathematical expression (1-2) and the following mathematical expression (2-2), The organic electroluminescent device satisfies the following mathematical expression (1-1) and the following mathematical expression (2-1), n3 - 0.25 < m3 < n3 + 0.25 (1-3) In the mathematical expression (1-3), n3 is an integer of 0 or more, and m3 is the number of interference orders between the reflective electrode and the center of light emission of the third light-emitting layer, In the general formula (2-3), m3 has the same meaning as m3 in the mathematical expression (1-3), L3 is an optical distance between the reflective electrode and the center of light emission of the third light-emitting layer, which is nm, λ3 is a peak wavelength of light emission from the third light-emitting layer, which is nm, and Φ3 is a phase change when the light emission from the third light-emitting layer is reflected by the reflective electrode, n2 - 0.25 < m2 < n2 + 0.25 (1-2) In the mathematical expression (1-2), n2 is an integer of 0 or more, and m2 is the number of interference orders between the reflective electrode and the center of light emission of the second light-emitting layer, In the mathematical expression (2-2), m2 has the same meaning as m2 in the mathematical expression (1-2), L2 is an optical distance between the reflective electrode and the center of light emission of the second light-emitting layer, which is nm, λ2 is a peak wavelength of light emission from the second light-emitting layer, which is nm, and Φ2 is a phase change when the light emission from the second light-emitting layer is reflected by the reflective electrode, n1 - 0.25 < m1 < n1 + 0.25 (1-1) In the mathematical expression (1-1), n1 is an integer of 0 or more, and m1 is the number of interference orders between the reflective electrode and the center of light emission of the first light-emitting layer, In the mathematical expression (2-1), m1 has the same meaning as m1 in the mathematical expression (1-1), L1 is an optical distance between the reflective electrode and the center of light emission of the first light-emitting layer, which is nm, λ1 is a peak wavelength of light emission from the first light-emitting layer, which is nm, and Φ1 is a phase change when the light emission from the first light-emitting layer is reflected by the reflective electrode.

128. The organic electroluminescent device according to any one of claims 1 to 127, wherein The anode is a reflective electrode, and light is extracted from the cathode side.

129. The organic electroluminescent device according to any one of claims 1 to 127, wherein The cathode is a reflective electrode, and light is extracted from the anode side.

130. An electronic device provided with the organic electroluminescent device according to any one of claims 1 to 129.

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