JPH08315986A - Organic electroluminescent element - Google Patents

Abstract

PURPOSE: To provide an organic electroluminescent element in which emissions of plural colors with sufficient luminances can be easily and efficiently performed. CONSTITUTION: A light emitting hole transporting layer 3 a light emitting electron transporting layer 4 and a light emitting layer 5 containing an organic material emitting fluorescence differed in color in visual area are provided between a hole injecting electrode 2 and an electron injecting electrode 6. In such an organic electroluminescent element, a non-light emitting hole transporting part 3a and a non-light emitting electron transporting part are partially provided between prescribed layers.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an organic electroluminescence device having a light emitting organic layer provided between a hole injecting electrode and an electron injecting electrode, and more particularly, it can easily and efficiently emit light of a plurality of colors. The present invention relates to an organic electroluminescence device.

[0002]

2. Description of the Related Art In recent years, along with the diversification of information equipment, the need for a flat display device that consumes less power and occupies less space than a CRT that has been generally used has been increased, and such a flat display device is required. As one of the above, an electroluminescence element (hereinafter, abbreviated as EL element) is receiving attention.

The EL element is roughly classified into an inorganic EL element and an organic EL element depending on the material used.
In the element, a high electric field is generally applied to the light emitting portion, electrons are accelerated in the high electric field to collide with the light emitting center, and thereby the light emitting center is excited to emit light. In the above, electrons and holes are respectively injected into the light emitting part from the electron injection electrode and the hole injection electrode, and the electrons and holes thus injected are recombined at the emission center to excite the organic material. The organic material emits fluorescence when the organic material returns from the excited state to the ground state.

In the inorganic EL element, since a high electric field is applied as described above, the driving voltage is 1
While a high voltage of 00 to 200 V is required, the above organic EL element has an advantage that it can be driven at a low voltage of about 5 to 20 V. In recent years, various studies have been conducted on such an organic EL element. It came to be done.

The element structure in such an organic EL element is called a DH structure in which a hole transport layer, a light emitting layer and an electron transport layer are laminated between a hole injection electrode and an electron injection electrode. A layer structure, a two-layer structure called SH-A structure in which a hole transport layer and an electron transporting light emitting layer are laminated between a hole injecting electrode and an electron injecting electrode, and a hole injecting electrode A two-layer structure called an SH-B structure, in which a light emitting layer having a hole transporting property and an electron transporting layer are stacked between a light emitting layer and an electron injecting electrode, has been generally known.

In the above organic EL device, a light emitting device which emits light in an appropriate color can be obtained by appropriately selecting a fluorescent substance which is a light emitting material.
In recent years, in order to use it as a display device for traffic signs, a multi-color display device, a full-color display device, or the like, research is being conducted to obtain light emission of a plurality of colors at the same time by using an organic EL element. Became.

In the prior art, in order to obtain light emission of a plurality of colors by using the organic EL element as described above, for example, in Japanese Patent Laid-Open No. 3-187192, a hole injection electrode and an electron injection electrode are provided. When providing a light-emitting layer between the two, using a mask to successfully bond multiple light-emitting layers with different emission peak wavelengths so that they do not overlap, forming a plurality of light-emitting layers on the same plane in a mosaic shape, each light emission It has been proposed that the layers can emit light of different colors.

However, as described above, it is very difficult to form a plurality of light emitting layers on the same plane by using the mask to properly bond the light emitting layers so as not to overlap each other.
There is a problem that the light emitting layers overlap each other at the joints of the light emitting layers, which lowers the emission brightness and changes the emission color.There is a gap at the joints of the light emitting layers, and the current flows through the gap. However, there is a problem in that light is leaked and light emission cannot be obtained.

Further, in Japanese Unexamined Patent Publication No. 6-68977, a plurality of organic EL elements having different emission peak wavelengths are stacked so that their light emitting portions do not overlap each other, and each organic EL element emits light to emit different colors. It has been proposed to obtain the above-mentioned luminescence.

However, in the device disclosed in the above publication, since a plurality of organic EL elements are stacked, the light emitted from the organic EL element located at a position away from the light extraction surface is conducted through another organic EL element. Therefore, this light is absorbed, reflected, or diffused by another organic EL element in the middle, so that the brightness of the light guided to the surface on the light extraction side is significantly reduced, and at the same time, the organic EL element is Since the color of the light emitted from the device may change on the way, there is a problem in that it is not possible to obtain light emission of an appropriate plurality of colors with sufficient brightness.

Further, in US Pat. No. 5,294,870, an organic E emitting blue light in the light emitting layer is disclosed.
By using an L element, the surface of the organic EL element on the side from which the light emitted is taken out, absorbs the blue light and absorbs the green light,
It has been proposed that each fluorescent layer that emits red light is provided to obtain light of a plurality of colors.

However, even in the case of the publication, since the low-energy visible light emitted in the light emitting layer is guided to each fluorescent layer through the transparent electrode or the glass substrate provided in the organic EL element, the light guided to the fluorescent layer is used. Is weak, and the light emitted while being guided to the fluorescent layer becomes weaker by being reflected, absorbed, or diffused by the transparent electrode or the glass substrate, and the fluorescent substance in each fluorescent layer is sufficiently excited. However, there is a problem in that it is difficult to emit green or red light in each fluorescent layer, and light of multiple colors having sufficient brightness cannot be obtained.

[0013]

SUMMARY OF THE INVENTION The present invention is an organic EL device.
It is an object of the present invention to solve the above problems in the case of emitting light of a plurality of colors using an element, and to provide an organic EL element capable of emitting light of a plurality of colors with sufficient brightness easily and efficiently. To do.

[0014]

In order to solve the above-mentioned problems, in the first organic electroluminescence device of the present invention, a different color is provided at least in the visible region between the hole injecting electrode and the electron injecting electrode. In the organic electroluminescent device, wherein the luminescent hole transport layer containing a fluorescent organic material and a luminescent electron transport layer are provided, and the luminescent hole transport layer emits light, wherein the luminescent hole transport layer is The non-emissive hole-transporting portion is partially provided between the light-emitting electron-transporting layer and the light-emitting electron-transporting layer.

Further, in the second organic electroluminescence device of the present invention, a luminescent hole transporting material containing an organic material that emits fluorescence of different colors at least in the visible region is provided between the hole injecting electrode and the electron injecting electrode. A layer and a luminescent electron transport layer are provided, and in the organic electroluminescent device in which the luminescent electron transport layer emits light, a non-luminous property is provided between the luminescent hole transport layer and the luminescent electron transport layer. That is, the electron transporting part is partially provided.

Further, in the third organic electroluminescent device of the present invention, a luminescent hole transporting material containing an organic material which emits fluorescence of different colors at least in the visible region is provided between the hole injecting electrode and the electron injecting electrode. A layer, a light emitting layer, and a light emitting electron transport layer are provided, and in the organic electroluminescent device in which the light emitting layer emits light, a non-light emitting electron transporting portion is provided between the light emitting hole transport layer and the light emitting layer. It is arranged to partially provide and / or partially provide a non-light emitting hole transporting portion between the light emitting layer and the light emitting electron transporting layer.

In each organic EL element of the present invention, a material having a large work function such as gold or ITO (indium-tin oxide) is used as the hole injecting electrode, while an electron injecting electrode is used. Uses an electrode material with a small work function such as magnesium, and
In order to extract light, at least one of the electrodes needs to be transparent, and in general, ITO having a large work function is used for the hole injecting electrode.

Further, each of the above organic ELs in the present invention
In the case of providing a light emitting hole transport layer or a light emitting electron transport layer in the device, a light emitting material having a low hole transport property or an electron transport property is used so that fluorescence of an appropriate color can be obtained and concentration quenching can be performed. In order to suppress and further facilitate the production of organic EL devices, in the case of a light emitting hole transport layer, a light emitting material suitable for the hole transport material used for the non-light emitting hole transport portion is contained. In the case of a luminescent electron transporting layer, it is preferable that a suitable luminescent material is contained in the electron transporting material used for the non-luminescent electron transporting portion.

[0019]

The operation of each of the above organic EL elements in the present invention will be described with reference to FIGS.

Here, in the first organic EL element, as shown in FIG. 1, the hole injection electrode 2 is provided on the substrate 1,
Between the hole injecting electrode 2 and the electron injecting electrode 6, a light emitting hole transporting layer 3 and a light emitting electron transporting layer 4 containing an organic material that emits fluorescence of different colors in the visible region are provided. In this state, the luminescent hole transport layer 3 emits light.

When the non-emissive hole-transporting portion 3a is partially provided between the light-emissive hole-transporting layer 3 and the light-emissive electron-transporting layer 4 as described above, the non-emissive hole-transporting portion 3a is transported. The portion 3a hinders the injection of electrons into the light-emitting hole transport layer 3 and suppresses the light emission in the light-emitting hole transport layer 3. Therefore, in the portion where the non-light emitting hole transporting portion 3a is provided, the light emitting electron transporting layer 4 emits light, and it is provided with the portion where the non-light emitting hole transporting portion 3a is not provided. Fluorescence of different color comes to be emitted from the part.

In addition, in the second organic EL element, as shown in FIG.
As shown in FIG. 3, a luminescent hole transport layer 3 and a luminescent electron transport layer 4 containing an organic material that emits fluorescence of different colors in the visible region are provided between the hole injection electrode 2 and the electron injection electrode 6. It is provided, and in this state, the luminescent electron transport layer 4 emits light.

When the non-emissive electron transporting portion 4a is partially provided between the light-emissive hole transporting layer 3 and the light-emissive electron transporting layer 4 as described above, the non-emissive electron transporting portion 4a is provided. The injection of holes into the luminescent electron transport layer 4 is hindered by the portion 4a, and the luminescence in the luminescent electron transport layer 4 is suppressed. Therefore, the non-luminous electron transporting portion 4a
In the portion where is provided, the hole transporting layer 3 having a light emitting property is provided.
Light is emitted, and fluorescent light of different colors is emitted between the portion where the non-emissive electron transporting portion 4a is not provided and the portion where it is provided.

In addition, in the third organic EL element, as shown in FIG.
As shown in FIG. 5, between the hole injecting electrode 2 and the electron injecting electrode 6, the luminescent hole transporting layer 3, the luminescent layer 5, and the luminescent electron transporting layer containing an organic material that emits fluorescence of different colors in the visible region. The layer 4 is provided, and in this state, the light emitting layer 5 emits light.

When the non-emissive electron transporting portion 4a is partially provided between the light-emissive hole transporting layer 3 and the light-emitting layer 5 as described above, the non-emissive hole transporting portion 3a emits light. The injection of electrons into the layer 5 is hindered, and the light emission in the light emitting layer 5 is suppressed. Therefore, in the portion where the non-light emitting hole transporting portion 3a is provided, the light emitting electron transporting layer 4 emits light, and it is provided with the portion where the non-light emitting hole transporting portion 3a is not provided. Fluorescence of different color comes to be emitted from the part.

Further, when the non-light emitting hole transporting portion 3a is partially provided between the light emitting layer 5 and the light emitting electron transporting layer 4, the non light emitting electron transporting portion 4a allows the light emitting layer 5 to be formed.
The injection of holes into the layer is hindered, and the light emission in the light emitting layer 5 is suppressed. Therefore, in the portion where the non-light emitting electron transporting portion 4a is provided, the light emitting hole transporting layer 3 emits light, and the non-light emitting electron transporting portion 4 is formed.
Fluorescence having different colors is emitted between the portion where a is not provided and the portion where a is provided.

Further, as shown in FIG. 3, a non-luminous electron transporting portion 4 is provided between the luminescent hole transporting layer 3 and the luminescent layer 5.
When a is partially provided and the non-emissive hole transporting portion 3a is partially provided between the light emitting layer 5 and the light emitting electron transporting layer 4, the non-emissive electron transporting portion 4a and the non-emissive electron transporting portion 4a are provided. In the portion where the hole transporting portion 3a is not provided, the light emitting layer 5 emits light, and in the portion where the non-light emitting electron transporting portion 4a is provided, the light emitting electron transporting layer 4 emits light and the non light emitting In the portion where the electron transporting portion 4a is provided, the luminescent hole transporting layer 3 emits light, and fluorescence of three different colors can be obtained.

In each of the above organic EL elements, by providing the non-emissive electron transporting portion 4a and the non-emissive hole transporting portion 3a in an appropriate shape, various displays of different colors are possible. become.

Further, a portion provided with a non-emissive hole transporting portion 3a, a portion provided with a non-emissive electron transporting portion 4a, a non-emissive electron transporting portion 4a and a hole transporting portion 3a.
And a portion not provided with are provided in a matrix, which is driven by a matrix electrode and a liquid crystal filter is turned on and off.
When controlled by FF, multi-color display with high display quality can be performed.

[0030]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be specifically described below with reference to the accompanying drawings.

Example 1 Organic E in this Example 1
The L element is an example of the first organic EL element, and has the structure shown in FIG.

Here, in the organic EL device of this example, indium-tin oxide (hereinafter,
It is called ITO. ) Is formed into a transparent hole injecting electrode 2 having a film thickness of 2000 Å.
The pyrazoline compound represented by the following chemical formula 1 (hereinafter referred to as PYR
-9. ) Is used to form a luminescent hole transport layer 3 having a film thickness of 500 Å, and N, N′-diphenyl-N, N′-bis (shown in the following chemical formula 2 is formed on the hole transport layer 3. 3-Methylphenyl) -1,1'-biphenyl-
Non-emissive hole transport part 3a having a film thickness of 100 Å using 4,4'-diamine (hereinafter referred to as MTPD).
Is partially formed, and a film thickness of 500 is formed on the hole transport layer 3 and the hole transport portion 3a by using an azomethine complex (hereinafter, referred to as 1AZM-Hex) represented by Chemical Formula 3 below.
The structure is such that the Å light emitting electron transport layer 4 is formed, and the electron injection electrode 6 made of a magnesium-indium alloy and having a film thickness of 2000 Å is formed on the electron transport layer 4. The lead wires 10 are connected to the hole injection electrode 2 and the electron injection electrode 6, respectively, so that a positive bias voltage is applied to the hole injection electrode 2 and a negative bias voltage is applied to the electron injection electrode 6.

[0033]

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[0034]

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[0035]

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In manufacturing the organic EL device of Example 1, the glass substrate 1 having the hole injecting electrode 2 made of ITO formed on the surface thereof was washed with a neutral detergent and then washed with acetone in acetone. Ultrasonic cleaning was performed for 20 minutes each in ethanol for 20 minutes.

Next, the above-mentioned PYR-9 is vacuum-deposited on the above-mentioned hole injecting electrode 2 formed on the glass substrate 1 to form a luminescent hole transport layer 3, and one of the holes on the hole transport layer 3 is formed. The MTPD was vacuum-deposited using a metal mask on the portion to partially form the non-emissive hole transporting portion 3a. Then, the 1AZM-Hex is vacuum-deposited on the hole transporting portion 3a and the hole transporting layer 3 to form a luminescent electron transporting layer 4, and magnesium on the electron transporting layer 4 is formed. The electron injection electrode 6 made of an indium alloy was formed by vacuum vapor deposition. All of these vacuum vapor depositions were performed by a resistance heating method using a molybdenum boat, and the degree of vacuum was 1 × 10 ⁻⁵ Torr or less.
The substrate temperature was 20 to 30 ° C.

Then, 10 V is applied between the hole injecting electrode 2 and the electron injecting electrode 6 in the organic EL device of the first embodiment.
In the region where the non-emissive hole transporting portion 3a is formed, blue light having a luminance of 400 cd / m ² and an emission peak wavelength of 460 nm is obtained, while the non-emissive hole transporting portion 3a is formed. In the non-illuminated region, the luminance is 1000 cd / m ² , the emission peak wavelength is 490n.
m blue-green light emission was obtained, and at the same time, blue and blue-green light emission could be obtained. According to the emission spectrum, the blue emission in the region where the non-emissive hole transporting portion 3a4 is formed is due to 1AZM-Hex used in the electron transporting layer 4, and the non-emissive hole transporting portion 3a is formed. It was confirmed that the blue-green light emission in the non-illuminated region was due to PYR-9 used in the hole transport layer 3.

(Example 2) The organic EL element of this Example 2 is also an example of the first organic EL element like the organic EL element of the above Example 1 and has the structure shown in FIG. There is.

Here, in the organic EL device of the second embodiment, the material of the light emitting hole transport layer 3 is the MT used in the non-light emitting hole transport portion 3a of the first embodiment.
PD and rubrene shown in Chemical formula 4 below, which is a light emitting material, are used so that 5 wt% of rubrene is contained in the above MTPD, and both are co-deposited on the hole injecting electrode 2 to emit light. In addition to forming the hole transport layer 3, the material for the electron transport layer 5 having a light-emitting property is tris (8-
Hydroxyquinoline) aluminum (hereinafter referred to as Alq ₃ ) was used, and otherwise the organic EL device was obtained in the same manner as in Example 1 above.

[0041]

[Chemical 4]

[0042]

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Then, 10 V is applied between the hole injection electrode 2 and the electron injection electrode 6 in the organic EL device of the second embodiment.
In the region where the non-emissive hole transporting portion 3a is formed, green light having a luminance of 1500 cd / m ² and an emission peak wavelength of 520 nm is obtained, while the non-emissive hole transporting portion 3a is formed. In the non-illuminated region, the luminance is 1300 cd / m ² , the emission peak wavelength is 560
Yellow emission of nm was obtained, and at the same time, emission of green and yellow could be obtained. According to the emission spectrum, the green emission in the region where the non-emissive hole transporting portion 3a is formed is due to Alq ₃ used in the electron transporting layer 5, and the non-emissive hole transporting portion 3a is formed. It was confirmed that the yellow light emission in the region where no light was emitted was due to rubrene used in the hole transport layer 3.

(Example 3) Organic E in this Example 3
The L element is an example of the second organic EL element and has the structure shown in FIG.

Here, in the organic EL element of this embodiment, the film thickness of ITO is 2000 Å on the transparent glass substrate 1.
A transparent hole injecting electrode 2 having a thickness of 500 Å is formed on the hole injecting electrode 2 by using PYR-9 shown in Chemical Formula 1 above. A non-emissive electron transporting portion 4a having a film thickness of 100 Å is partially formed on the hole transporting layer 3 by using the oxadiazole compound represented by the following chemical formula 6 (hereinafter referred to as OXD-7). A film thickness of 5 is formed on the hole transport layer 3 and the electron transport portion 4a by using Alq ₃ shown in Chemical formula 5 above.
The structure is such that a luminescent electron transport layer 4 having a thickness of 00 Å is formed, and an electron injection electrode 6 made of a magnesium-indium alloy and having a thickness of 2000 Å is further formed on the electron transport layer 4. The lead wires 10 are connected to the hole injection electrode 2 and the electron injection electrode 6, respectively, so that a positive bias voltage is applied to the hole injection electrode 2 and a negative bias voltage is applied to the electron injection electrode 6.

[0046]

[Chemical 6]

In manufacturing the organic EL device of Example 3, the glass substrate 1 having the hole injecting electrode 2 made of ITO formed on the surface thereof was washed with a neutral detergent and then washed with acetone in acetone. Ultrasonic cleaning was performed for 20 minutes each in ethanol for 20 minutes.

Next, the above-mentioned PYR-9 is vacuum-deposited on the above-mentioned hole injecting electrode 2 formed on the glass substrate 1 to form a light-emitting hole transport layer 3, and one of the holes on the hole transport layer 3 is formed. The above-mentioned OXD-7 using a metal mask for the part
Was vacuum-deposited to partially form the non-luminous electron transporting portion 4a. Then, the Alq ₃ is vacuum-deposited on the electron transporting portion 4a and the hole transporting layer 3 to form a luminescent electron transporting layer 4, and magnesium / indium is further deposited on the electron transporting layer 5. The electron injection electrode 6 made of an alloy was formed by vacuum vapor deposition. All of these vacuum vapor depositions were carried out by a resistance heating method using a molybdenum boat, under conditions of a vacuum degree of 1 × 10 ⁻⁵ Torr or less and a substrate temperature of 20 to 30 ° C.

Then, 10 V is applied between the hole injecting electrode 2 and the electron injecting electrode 6 in the organic EL device of the third embodiment.
In the region where the non-emissive electron transporting portion 4a is formed, blue-green light emission with a luminance of 2000 cd / m ² and an emission peak wavelength of 490 nm is obtained, while the non-emissive electron transporting portion 4a is formed. In the non-illuminated region, the luminance is 1500 cd / m ² , and the emission peak wavelength is 520n.
m green light emission was obtained, and at the same time, blue green light and green light emission could be obtained. According to the emission spectrum, the blue-green light emission in the region where the non-emissive electron transporting portion 4a is formed is due to PYR-9 used in the hole transporting layer 3, and the non-emissive electron transporting portion 4a is The green light emission in the region not formed is Al used in the electron transport layer 4.
It was confirmed to be due to q ₃ .

Example 4 Like the organic EL element of Example 3, the organic EL element of Example 4 is also an example of the second organic EL element and has the structure shown in FIG. There is.

Here, in the organic EL device of the fourth embodiment, the material of the light emitting electron transport layer 5 is used as the material of the third embodiment.
O used in the non-emissive electron transporting part 4a in
Using XD-7 and the above-mentioned rubrene which is a light emitting material,
5 weight% of rubrene is contained in the OXD-7, and both are co-deposited on the hole transport layer 3 and the electron transport portion 4a to form a luminescent electron transport layer 5. An organic EL device was obtained in the same manner as in Example 3 except for the above.

Then, 10 V is applied between the hole injecting electrode 2 and the electron injecting electrode 6 in the organic EL device of the fourth embodiment.
In the region where the non-emissive electron transporting portion 4a is formed, blue-green light emission with a luminance of 2000 cd / m ² and an emission peak wavelength of 490 nm is obtained, while the non-emissive electron transporting portion 4a is formed. In the non-illuminated region, the luminance is 1000 cd / m ² , the emission peak wavelength is 560 n.
m yellow emission was obtained, and at the same time blue-green and yellow emission could be obtained. According to the emission spectrum, the blue-green light emission in the region where the non-emissive electron transporting portion 4a is formed is due to PYR-9 used in the hole transporting layer 3, and the non-emissive electron transporting portion 4a is It was confirmed that the yellow light emission in the region where no electron was formed was due to rubrene used in the electron transport layer 4.

(Embodiment 5) The organic EL element of this embodiment 5 is an example of the third organic EL element and has the structure shown in FIG.

Here, the organic EL device of this Example 5 is
On the transparent glass substrate 1, indium-tin oxide (IT
A transparent hole injecting electrode 2 made of O) having a film thickness of 2000 Å is formed, and the PYR-9 shown in the chemical formula 1 is used on the hole injecting electrode 2 to obtain a light emitting film having a film thickness of 500 Å. A hole transport layer 3 is formed, and a film thickness of 100 Å is formed on the hole transport layer 3 by using OXD-7 shown in the chemical formula 6 above.
Partially forming the non-emissive electron transporting portion 4a
On the hole transport layer 3 and the electron transport portion 4a, a light emitting layer 5 having a film thickness of 100 Å is formed by using Eu (TTA) ₃ phen shown in Chemical formula 7 below, and the light emitting layer 5 is formed on the light emitting layer 5. The MTPD shown in Chemical Formula 2 above is used to partially form a non-luminous hole transporting portion 3a having a film thickness of 100 liters, and the chemical formula 3 above is formed on the hole transporting portion 3a and the light emitting layer 5.
1AZM-Hex shown in FIG. 1 is used to form a luminescent electron transport layer 4 having a film thickness of 500Å, and an electron injection electrode 6 made of a magnesium-indium alloy and having a film thickness of 2000Å is further formed on the electron transport layer 4. It has a formed structure. Then, the hole injection electrode 2 and the electron injection electrode 6 described above
A lead wire 10 is connected to and, respectively, so that a positive bias voltage is applied to the hole injecting electrode 2 and a negative bias voltage is applied to the electron injecting electrode 6.

[0055]

[Chemical 7]

Then, in manufacturing the organic EL device of Example 5, the glass substrate 1 having the hole injecting electrode 2 made of ITO formed on the surface thereof was washed with a neutral detergent and then washed with acetone in acetone. Ultrasonic cleaning was performed for 20 minutes each in ethanol for 20 minutes.

Next, the above-mentioned PYR-9 is vacuum-deposited on the above-mentioned hole injecting electrode 2 formed on the glass substrate 1 to form a luminescent hole transporting layer 3, and one of the holes on the hole transporting layer 3 is formed. The above-mentioned OXD-7 using a metal mask for the part
Is vacuum-deposited to partially form the non-emissive electron-transporting portion 4a, and the Eu (TTA) ₃ phen is vacuum-deposited on the electron-transporting portion 4a and the hole-transporting layer 3. The light emitting layer 5 was formed. Then, using the metal mask on the light emitting layer 5, the MTPD is vacuum-deposited on the portion where the non-emissive electron transporting portion 4a is not provided to partially form the non-emissive hole transporting portion 3a. 1AZM-Hex is vacuum-deposited on the hole-transporting portion 3a and the light-emitting layer 5 to form a luminescent electron-transporting layer 4. Then, a magnesium-indium alloy is formed on the electron-transporting layer 4. The electron injection electrode 6 is formed by vacuum vapor deposition. All of these vacuum vapor depositions were carried out by a resistance heating method using a molybdenum boat under the conditions of a vacuum degree of 1 × 10 ⁻⁵ Torr or less and a substrate temperature of 20 to 30 ° C.

Then, 10 V is applied between the hole injecting electrode 2 and the electron injecting electrode 6 in the organic EL device of the fifth embodiment.
In the region where the non-emissive electron transporting portion 4a is formed, a blue-green light emission with a luminance of 500 cd / m ² and an emission peak wavelength of 490 nm is obtained, and a non-emissive hole transporting portion 3a is formed. Brightness is 2
A blue light emission with an emission peak wavelength of 460 nm of 00 cd / m ² is obtained, and a luminance of 50 is obtained in a region where the non-emissive electron transporting portion 4a and hole transporting portion 3a are not formed.
Red light emission of cd / m ² and an emission peak wavelength of 615 nm was obtained, and at the same time light emission of three colors of blue-green and blue and red could be obtained. According to the emission spectrum, the blue-green light emission in the region where the non-emissive electron transporting portion 4a is formed is due to the PYR-9 used in the hole transporting layer 3. The blue emission in the formed region is 1AZM-He used in the electron transport layer 4.
The red light emission in the region where the non-emissive electron transporting portion 4a and the hole transporting portion 3a are not formed is caused by x. Eu (TTA) ₃ phen used in the light emitting layer 5.
It was confirmed that it was due to.

(Example 6) In manufacturing the organic EL device of Example 6, as shown in FIG. 4, the hole injection electrode 2 made of ITO was formed on the glass substrate 1 with a line width d1 of 0.4 mm, After forming a stripe shape with a center distance d2 of 0.5 mm, this was washed with a neutral detergent and further washed with acetone for 20 minutes and then with ethanol for 2 minutes.
Ultrasonic cleaning was performed for 0 minutes.

Next, as shown in FIG. 5, on the glass substrate 1 on which the hole injecting electrode 2 is formed, M shown in the above chemical formula 2 is formed.
Lubrene shown in the chemical formula 4 was contained in 5% by weight with respect to TPD, and both were co-evaporated to form a luminescent hole transport layer 3.

Then, as shown in FIG. 6, the metal mask 11 having 0.45 mm square holes 11 opened vertically and horizontally at intervals of 0.55 mm is used, and the 0.45 mm square holes in the metal mask 11 are used. As shown in FIG. 7, the center of 11a and the center of the stripe of the hole injecting electrode 2 are overlapped with each other, and M shown in the chemical formula 2 is formed on the hole transporting layer 3.
Each hole 11 of the metal mask 11 is formed by vacuum-depositing TPD.
A non-luminous hole transporting portion 3a corresponding to the portion a was formed.

Next, as shown in FIG. 8, 1AZM-Hex shown in the above chemical formula is evacuated onto the hole transport layer 3 including the region where the non-emissive hole transport portion 3a is formed as described above. To form a luminescent electron transport layer 4, and an electron injection electrode 6 made of a magnesium-indium alloy is vacuum-deposited on the electron transport layer 4 so as to be orthogonal to the hole injection electrode 2 as shown in FIG. In the direction of
As in the case of the hole injection electrode 2, the line width d1 is 0.4 m
m, the center interval d2 was 0.5 mm, and the stripes were formed so that the center of the stripe-shaped electron injection electrode 6 overlaps the center of the dot of the non-emissive hole transporting portion 3a. .

Each of the above-mentioned vacuum vapor depositions was carried out by a resistance heating method using a molybdenum boat under the conditions of a vacuum degree of 1 × 10 ⁻⁵ Torr or less and a substrate temperature of 20 to 30 ° C.

When a voltage of 10 V is applied between the hole injecting electrode 2 and the electron injecting electrode 6 in the display panel composed of the organic EL device of this Example 6 thus produced, as shown in FIG. In the lattice portion where the non-emissive hole transporting portion 3a is formed, the brightness of 4
1 AZM with 00 cd / m ² and emission peak wavelength of 460 nm
While blue light emission by -Hex is obtained, in the lattice portion where the non-emissive hole transporting portion 3a is not formed,
Yellow emission was obtained by rubrene having a luminance of 800 cd / m ² and an emission peak wavelength of 560 nm, and when this display was driven, images of various emission colors from blue to yellow could be displayed.

The organic EL devices of Examples 2, 4 and 6 above
In the device, rubrene was used as the light emitting material contained in the hole transporting layer 3 and the electron transporting layer 4, but the light emitting material used is not limited to this and various known light emitting materials can be used. , Tetraphenyl butadiene shown in Chemical formula 8, coumarin 343 shown in Chemical formula 9, and chemical formula 1 having an emission color and an emission peak wavelength as shown in Table 1 below.
Coumarin 6 shown in 0, quinacridone shown in Chemical formula 11,
NK-757 shown in Chemical formula 12, DCM shown in Chemical formula 13,
Zn (ac) ₂ shown in Chemical formula 14 or the like can be used.

[0066]

[Table 1]

[0067]

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[0068]

[Chemical 9]

[0069]

[Chemical 10]

[0070]

[Chemical 11]

[0071]

[Chemical 12]

[0072]

[Chemical 13]

[0073]

Embedded image

Regarding the amount of the luminescent material to be contained, the content of rubrene, which is the luminescent material, was set to 5% by weight in each of the above-mentioned examples, but the content is not limited to this and may be used. It can be changed as necessary to suit the properties of the light emitting material or the like and to adjust the emission color or brightness.

Further, in the organic EL devices of the above-mentioned respective embodiments, the hole transporting layer 3 and the electron transporting layer 4 which are in contact with the hole injecting electrode 2 and the electron injecting electrode 6 are single layers. In order to improve transportability, the layer in contact with the hole injecting electrode 2 may be a laminated layer or a mixed layer using a plurality of hole transporting materials having different ionization potentials,
Further, the layer in contact with the electron injection electrode 6 may be a laminated layer or a mixed layer using a plurality of electron transport materials having different electron affinities.

Further, in the organic EL devices of the above-mentioned respective embodiments, the film thickness of the non-emissive hole transporting portion 3a and the non-emissive electron transporting portion 4a is made extremely thin as 100Å. This is to suppress as much as possible the decrease in the brightness due to the increase in the thickness of the portion of FIG. However, the film thickness of the non-emissive hole transporting portion 3a and the non-emissive electron transporting portion 4a is not limited to this, and the region other than the region in which the hole transporting portion 3a and the electron transporting portion 4a are formed is not limited. When the brightness in the area is low, the hole transport section 3a and the electron transport section 4a
The film thickness can be changed to an appropriate film thickness in consideration of the balance with other light emitting regions and the effect of display, for example, by increasing the film thickness of the film and lowering the brightness.

[0077]

As described above in detail, in the organic EL device of the present invention, the non-emissive hole transporting portion and the non-emissive electron transporting portion are provided, and a portion provided with these and a portion not provided with In this case, since different colors of light are emitted, by forming the non-emissive hole transporting section and the non-emissive electron transporting section into appropriate shapes such as letters and pictures, it is possible to achieve high display quality. It is now possible to use such displays as traffic signs, information boards, etc.

Further, in the organic EL element of the present invention, a portion provided with a non-emissive hole transporting portion and a non-emissive electron transporting portion, and a portion not provided with these are arranged in a matrix, and this is arranged in a matrix. By controlling by driving with electrodes and turning on and off the liquid crystal filter, it has become possible to easily perform multi-color display and full-color display with high display quality.

[Brief description of drawings]

FIG. 1 is a first organic E in Examples 1 and 2 of the invention.
It is a schematic explanatory drawing which showed the element structure of L element.

FIG. 2 is a second organic E in Examples 3 and 4 of the present invention.
It is a schematic explanatory drawing which showed the element structure of L element.

FIG. 3 is a schematic explanatory view showing an element structure of a third organic EL element in Example 5 of the present invention.

FIG. 4 is a plan view showing a state in which hole injection electrodes are formed in stripes on a glass substrate in manufacturing the organic EL element in Example 6 of the present invention.

FIG. 5 is a plan view showing a state in which a luminescent hole transport layer is formed on the above hole injection electrode in manufacturing the organic EL device of Example 6.

FIG. 6 is a plan view of a metal mask used to partially form a non-emissive hole transport portion on the hole transport layer in manufacturing the organic EL device of Example 6;

FIG. 7 is a plan view showing a state in which a non-light emitting hole transporting portion is partially formed on the hole transporting layer in manufacturing the organic EL device of Example 6.

FIG. 8 is a plan view showing a state in which a luminescent electron transport layer is formed on a hole transport layer in which a non-luminescent hole transport portion is partially formed in manufacturing the organic EL device of Example 6. Is.

FIG. 9 is a plan view showing a state in which electron injection electrodes are formed in stripes on the electron transport layer in manufacturing the organic EL device of Example 6.

FIG. 12 is a plan view showing a state of colors emitted in a portion provided with a non-light emitting hole transporting portion and a portion not provided with it in the organic EL device of Example 6.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Substrate 2 Hole injecting electrode 3 Emissive hole transporting layer 3a Non-emissive hole transporting part 4 Emitting electron transporting layer 4a Non-emissive electron transporting part 5 Light emitting layer 6 Electron injecting electrode

[Procedure amendment]

[Submission date] October 26, 1995

[Procedure Amendment 1]

[Document name to be amended] Statement

[Name of item to be corrected] Brief description of the drawing

[Correction method] Change

[Correction content]

[Brief description of drawings]

FIG. 1 is a first organic E in Examples 1 and 2 of the invention.
It is a schematic explanatory drawing which showed the element structure of L element.

FIG. 2 is a second organic E in Examples 3 and 4 of the present invention.
It is a schematic explanatory drawing which showed the element structure of L element.

FIG. 3 is a schematic explanatory view showing an element structure of a third organic EL element in Example 5 of the present invention.

FIG. 4 is a plan view showing a state in which hole injection electrodes are formed in stripes on a glass substrate in manufacturing the organic EL element in Example 6 of the present invention.

FIG. 5 is a plan view showing a state in which a luminescent hole transport layer is formed on the above hole injection electrode in manufacturing the organic EL device of Example 6.

FIG. 6 is a plan view of a metal mask used to partially form a non-emissive hole transport portion on the hole transport layer in manufacturing the organic EL device of Example 6;

FIG. 7 is a plan view showing a state in which a non-light emitting hole transporting portion is partially formed on the above hole transporting layer in manufacturing the organic EL device of Example 6.

FIG. 8 is a plan view showing a state in which a luminescent electron transport layer is formed on a hole transport layer in which a non-luminescent hole transport portion is partially formed in manufacturing the organic EL device of Example 6. Is.

FIG. 9 is a plan view showing a state in which electron injection electrodes are formed in stripes on the electron transport layer in manufacturing the organic EL device of Example 6.

FIG. 10 is a plan view showing a state of colors emitted in a portion provided with a non-light emitting hole transporting portion and a portion not provided with it in the organic EL element of Example 6.

[Explanation of reference numerals] 1 substrate 2 hole injecting electrode 3 light emitting hole transporting layer 3a non-light emitting hole transporting portion 4 light emitting electron transporting layer 4a non light emitting electron transporting portion 5 light emitting layer 6 electron injecting electrode

 ─────────────────────────────────────────────────── ─── Continued front page (72) Inventor Kosuke Takeuchi 2-5-5 Keihan Hondori, Moriguchi-shi, Osaka Sanyo Electric Co., Ltd. (72) Inventor Kenichi Shibata 2-chome, Keihan Hondori, Moriguchi-shi, Osaka No. 5 Sanyo Electric Co., Ltd.

Claims (3)

[Claims] 1. A luminescent hole transporting layer and a luminescent electron transporting layer are provided between a hole injecting electrode and an electron injecting electrode, the luminescent hole transporting layer and the luminescent electron transporting layer containing an organic material that emits fluorescence of different colors at least in a visible region. In the organic electroluminescence device in which the light emitting hole transport layer emits light, a non-light emitting hole transport portion is partially provided between the light emitting hole transport layer and the light emitting electron transport layer. Characteristic organic electroluminescence device. 2. A luminescent hole transporting layer and a luminescent electron transporting layer containing an organic material that emits fluorescence of different colors at least in the visible region are provided between the hole injecting electrode and the electron injecting electrode, In the organic electroluminescent device in which the light-emitting electron transport layer emits light, a non-light-emitting electron transport portion is partially provided between the light-emitting hole transport layer and the light-emitting electron transport layer. Characteristic organic electroluminescence device. 3. A luminescent hole transporting layer, a luminescent layer, and a luminescent electron transporting layer containing an organic material that emits fluorescence of different colors at least in the visible region are provided between the hole injecting electrode and the electron injecting electrode. In the organic electroluminescence device, wherein the light emitting layer emits light, a non-light emitting electron transporting portion is partially provided between the light emitting hole transport layer and the light emitting layer and / or emits light from the light emitting layer. An organic electroluminescent device, characterized in that a non-emissive hole transporting portion is partially provided between the organic electroluminescent layer and the electron transporting layer.