JP4737369B2 - Manufacturing method of organic EL element - Google Patents

Description

  The present invention relates to a method for producing an organic EL element having a plurality of light emitting layers exhibiting different emission colors.

  Conventionally, as an organic EL element, a transparent electrode made of ITO (Indium Tin Oxide) or the like to be an anode, an organic layer made of a hole injection layer, a hole transport layer, a light emitting layer, an electron transport layer, or the like, and a cathode It is known that a non-translucent back electrode made of aluminum (Al) or the like is sequentially stacked and formed. For example, as disclosed in Patent Document 1, at least 2 as the light emitting layer is disclosed. A layered structure of light emitting layers exhibiting more than one kind of different emission colors is known. Such an organic EL element can obtain display light of a predetermined color by mixing the light emitting layers exhibiting different emission colors. For example, a white display can be obtained by stacking a blue light emitting layer and a yellow light emitting layer. Light can be obtained.

Further, in the manufacturing process of the organic EL element, foreign matter such as dust or dust having a size of several μm or less may be mixed in a vacuum chamber when the electrodes and the layers are formed by vapor deposition or sputtering. When the organic layer is formed with the foreign matter adhered on the transparent electrode, the very thin organic layer having a thickness of 10 nm to 100 nm is partially further thinned, and the back electrode is formed on the organic layer. When formed, the transparent electrode and the back electrode could be short-circuited or leaked. In order to solve such a problem, the applicant of the present invention disclosed in Patent Document 2 that after forming the organic EL element on the support substrate, a predetermined gap between both electrodes in a nitrogen atmosphere having a predetermined oxygen concentration was obtained. A method is proposed in which an energization process of applying a voltage is performed, and at least a portion of the back electrode in contact with the transparent electrode is removed and peeled off from the transparent electrode.
JP-A-12-68057 JP 2003-282249 A

  However, the organic EL element that has been subjected to the energization treatment has a problem that the chromaticity of the display light obtained depending on the current density is greatly changed, making it impossible to obtain display light of the target color. Such a problem is particularly prominent in an organic EL element in which a plurality of the light emitting layers having different emission colors are stacked. The organic EL element emits light with high luminance at a high current density and has a low current density. There are cases where the emission color obtained differs depending on when the device emits light with low luminance. This is because the light emission luminance of each light emitting layer obtained with respect to the current density by performing the energization process changes to a different degree depending on each light emitting layer.

  FIG. 5 is a diagram showing the relationship between the chromaticity of display light and the current density before and after the energization process in a conventional organic EL device in which a yellow light emitting layer and a blue light emitting layer are stacked as the light emitting layer. The x value and y value of the CIE chromaticity coordinates in FIG. 5 indicate values when a predetermined reference value is 0. The yellow light-emitting layer is formed, for example, by doping a host material made of IDE120 manufactured by Idemitsu Kosan Co., Ltd. with a light-emitting material showing yellow light emission made of, for example, a naphthacene derivative, and further, for example, holes such as α-NPD Transportable materials have been added. The blue light-emitting layer is formed by doping a host material similar to the yellow light-emitting layer with, for example, a light-emitting material showing blue light emission made of BD102 made by Idemitsu Kosan Co., Ltd., and further adding the hole transporting material. It has been. In FIG. 5A, a characteristic S5 indicates a relationship between an x value of CIE chromaticity coordinates of display light and a current density in the conventional organic EL element before the energization process, and a characteristic S6 indicates the energization. The relationship between the x value of the CIE chromaticity coordinate of the display light and the current density in the conventional organic EL element after processing is shown. In FIG. 5B, a characteristic S7 indicates the relationship between the y value of the CIE chromaticity coordinates of the display light and the current density in the conventional organic EL element before the energization process, and the characteristic S8 is The relationship between the y value of the CIE chromaticity coordinate of the display light and the current density in the conventional organic EL element after the energization process is shown. As shown in FIG. 5, the conventional organic EL element after the energization processing is particularly when the chromaticity change amount Δx of the x value of the CIE chromaticity coordinates of the display light with respect to the current density, that is, when the current density is changed. The difference between the maximum value and the minimum value of the x value of the CIE chromaticity coordinates of the display light is larger than that before the energization process, and the emission color obtained by the light emission driving at the low current density and the light emission driving at the high current density is obtained. Is different.

  In view of such a problem, the present invention is an organic EL device capable of obtaining a target luminescent color regardless of the current density even when an energization process of applying a predetermined voltage is performed after the organic EL element is formed. An object is to provide a method for manufacturing an element.

In order to solve the above-mentioned problems, the present invention provides a method for producing an organic EL element comprising an organic layer having at least a plurality of light-emitting layers having different emission colors and sandwiched between a pair of electrodes.
A step of forming each light emitting layer so that the amount of change in chromaticity of display light with respect to the current density is greater than 0.02, and a predetermined voltage is applied between the electrodes after the formation of the electrodes and the organic layer. and performing energization processing for, Ri name contains at least a
In the step of forming each light emitting layer, each light emitting layer is formed by mixing a light emitting material with a host material, or each light emitting layer is mixed with a light emitting material with a host material, and further a hole transporting material or electron Formed by adding a transport material, the thickness of the light emitting layer having at least a short emission wavelength among the light emitting layers, the concentration of the light emitting material contained in the light emitting layer having at least a short emission wavelength among the light emitting layers, The concentration of the hole transporting material contained in the light emitting layer having a short emission wavelength among the light emitting layers, the concentration of the electron transporting material contained in the light emitting layer having a short emission wavelength among the light emitting layers, or these By adjusting the amount of change in chromaticity of the display light with respect to the current density,
In the step of performing the energization processing, performs the energization processing by heating the organic layer over 50 ° C., Ru and remove a portion in contact with the other electrode of the one electrode is peeled from the other electrode It is characterized by that.

  Further, the energization process is performed such that the chromaticity change amount of the display light with respect to the current density after the energization process is 0.02 or less.

  Further, in the step of performing the energization process, a predetermined voltage is applied between the electrodes in the reverse bias direction.

  Further, in the step of performing the energization process, the energization process is performed in a nitrogen atmosphere having a predetermined oxygen concentration.

  The present invention relates to a method for manufacturing an organic EL element having a plurality of light emitting layers exhibiting different luminescent colors, and even when an energization process of applying a predetermined voltage is performed after the organic EL element is formed, the current density is adjusted. Regardless, it is possible to obtain a target emission color.

  Hereinafter, an embodiment in which the present invention is applied to a segment type organic EL panel will be described with reference to the accompanying drawings.

  In FIG. 1, the organic EL panel is formed by arranging an organic EL element 1 on a translucent support substrate 2. The organic EL element 1 mainly includes a translucent first electrode 3, an insulating layer 4, an organic layer 5, and a second electrode 6. Further, a sealing member 7 is disposed on the support substrate 2 so as to cover the organic EL element 1 in an airtight manner. Such an organic EL panel takes out light emitted from the organic EL element 1 from the support substrate 2 side, and obtains white display light by a complementary color of yellow light emission of a first light emitting layer and blue light emission of a second light emitting layer described later. It is.

  The support substrate 2 is a translucent glass substrate having a rectangular shape.

  The first electrode 3 serves as an anode, and a conductive material such as ITO is formed on the support substrate 2 in a layered form with a film thickness of 50 to 200 nm by means such as sputtering, and the photolithography method or the like is used for example. It is formed by patterning according to the character-shaped display design, and is provided at the day-shaped display segment portion 3a, the lead portion 3b that is drawn from each display segment 3a, and the terminal portion of the lead portion 3b. Electrode portion 3c. The electrode portion 3c is concentrated on one side of the support substrate 2.

  The insulating layer 4 is made of an insulating material such as polyimide or phenol, and is formed in a layer shape by means such as sputtering, and is formed into a predetermined shape on a non-light emitting portion on the support substrate 2 by means such as photolithography. Formed. The insulating layer 4 has a window portion 4a corresponding to the display segment 3a and a notch portion 4b corresponding to an electrode portion to be described later of the second electrode 6, and displays the outline of the light emitting region clearly. A window 4a is formed so as to slightly overlap the peripheral edge of the display segment 3a of the electrode 3, and is disposed so as to cover the lead 3b in order to ensure insulation between the first electrode 3 and the second electrode 6. Is done.

  The organic layer 5 is formed with a predetermined size on the first electrode 3 and the insulating layer 4 so as to correspond to the location of the window 4a in the insulating layer 4, and as shown in FIG. The hole transport layer 5a, the first light emitting layer 5b, the second light emitting layer 5c, the electron transport layer 5d, and the electron injection layer 5e are sequentially laminated by means such as vapor deposition.

  The hole transport layer 5a has a function of taking holes from the first electrode 3 and transmitting the holes to the light emitting layer 5c. For example, a hole transport material such as α-NPD is formed into a film by means such as vapor deposition. It is formed in a layer shape having a thickness of 10 to 60 nm.

  The first light emitting layer 5b is an organic material that is capable of transporting holes and electrons and has a hole transport property that is higher than the electron mobility. For example, IDE120 manufactured by Idemitsu Kosan Co., Ltd. A host material composed of, for example, a naphthacene derivative having a function of emitting light in response to recombination of electrons and holes, and the above-described hole transporting material constituting the hole transport layer 5a. One luminescent material is mixed by means such as co-evaporation, and formed into a layer having a thickness of, for example, about 20 nm.

  The second light-emitting layer 5c is capable of transporting holes and electrons, and the same host material as the first light-emitting layer 5b is combined with the hole-transporting material constituting the hole-transporting layer 5a and the electrons. Second light emission composed of, for example, BD102 manufactured by Idemitsu Kosan Co., Ltd., which has a function of emitting light in response to recombination of light and holes and exhibits blue light emission having a shorter emission wavelength than the yellow light emission of the first light emitting layer 5b. The material is mixed by means such as co-evaporation, and is formed into a layer thicker than the first light emitting layer 5b having a thickness of, for example, about 30 nm. Further, in the second light emitting layer 5c, the concentration of the hole transporting material in the entire layer is higher than the concentration of the hole transporting material in the entire blue light emitting layer of the conventional organic EL element shown in FIG. For example, it is 20% or more higher.

  The electron transport layer 5d has a function of transmitting electrons to the second light-emitting layer 5c. For example, an electron transport material such as aluminum quinolinol (Alq3), which is a chelate compound, has a thickness of 20 to 20 by means of a vapor deposition method or the like. It is formed in a 60 nm layer.

  The electron injection layer 5e has a function of injecting electrons from the second electrode 6. For example, lithium fluoride (LiF) or the like is formed in a layer shape having a film thickness of about 1 nm by means such as vapor deposition.

  The second electrode 6 serves as a cathode, and is formed by forming a conductive material such as aluminum (Al) or magnesium silver (Mg: Ag) into a layer having a thickness of 50 to 200 nm by means such as vapor deposition. And electrically connected to a lead portion 6 a provided on one side of the support substrate 2. Note that an electrode portion (leading portion) 6b is provided at the end portion of the lead portion 6a, and the lead portion 6a and the electrode portion 6b are formed of the same material as the first electrode 3.

  The sealing member 7 is formed by forming a concave portion 7a in a flat plate member made of, for example, a glass material by an appropriate method such as sandblasting, cutting, and etching. The sealing member 7 is airtightly disposed on the support substrate 2 via an adhesive (not shown) made of, for example, an ultraviolet curable epoxy resin, with the support portion 7b formed so as to surround the recess 7a. The organic EL element 1 is sealed with the sealing member 7 and the support substrate 2. The sealing member 7 is configured to be slightly smaller than the support substrate 2 so that the electrode portion 3c of the first electrode 3 and the electrode portion 6b of the second electrode 6 are exposed to the outside.

  Next, the manufacturing method of the organic EL element 1 and the organic EL panel will be described with reference to FIG.

  First, a conductive material such as ITO is formed on the support substrate 2 in a layer shape having a film thickness of 50 to 200 nm by means such as sputtering, and is further patterned according to the display design by the photolithography method or the like, thereby displaying the display segment portion 3a. The first electrode 3 having the lead portion 3b and the electrode portion 3c and serving as an anode is formed (see FIG. 3A). At this time, the lead portion 6 a and the electrode portion 6 b are formed of the same material as the first electrode 3.

  Next, an insulating material such as polyimide or phenol is formed into a layer by means of sputtering or the like, and the portion corresponding to the display segment 3a of the first electrode 3 and the electrode of the second electrode 6 by means of photolithography or the like The insulating layer 4 having the window portion 4a and the cutout portion 4b is formed by removing the portion corresponding to the portion 6b (see FIG. 3B).

  Next, the organic layer 5 having a predetermined size is formed on the first electrode 3 and the insulating layer 4 so as to correspond to the location of the window 4a in the insulating layer 4 (see FIG. 3C). Specifically, the hole transport layer 5a, the first light-emitting layer 5b, the second light-emitting layer 5c, the electron transport layer 5d, and the electron injection layer 5e are sequentially stacked by means such as vapor deposition to form the organic layer 5. . First, the hole transport material is formed into a layer having a film thickness of 10 to 60 nm by means such as vapor deposition to obtain the hole transport layer 5a. Next, the host material, the hole transporting material, and the first light emitting material are mixed by means such as co-evaporation, and formed into a layer having a thickness of about 20 nm, for example, to obtain the first light emitting layer 5b. . Next, the host material, the hole transporting material, and the second light emitting material are mixed by means of a co-evaporation method or the like to form a layer having a film thickness of, for example, about 30 nm, and the second light emitting layer 5c is formed. obtain. In the step of forming the first and second light emitting layers 5b and 5c, in the present embodiment, in the second light emitting layer 5c, the concentration of the hole transporting material in the entire layer is as shown in FIG. The hole transport material is mixed so as to be 20 percent or more higher than the concentration of the hole transport material in the entire blue light emitting layer of the organic EL element. By mixing a large amount of the hole transporting material, the second light emitting layer 5c can have a light emission peak intensity larger than that of the blue light emitting layer of the conventional organic EL element. It is possible to adjust the chromaticity change amount in the CIE chromaticity coordinates with respect to the current density of the display light. In the present embodiment, by increasing the light emission peak intensity of the second light emitting layer 5b, the chromaticity change of the x value of the CIE chromaticity coordinates with respect to the current density of the display light of the organic EL element 1 before energization processing described later is performed. The amount is adjusted to be greater than 0.02 (more preferably greater than 0.03). After the formation of the first and second light emitting layers 5b and 5c, the electron transporting material is formed into a layer having a film thickness of 20 to 60 nm by means such as vapor deposition to obtain the electron transport layer 5d. Further, for example, lithium fluoride (LiF) or the like is formed into a layer having a film thickness of about 1 nm by means such as vapor deposition to obtain the electron injection layer 5e.

  Next, a conductive material such as aluminum (Al) or magnesium silver (Mg: Ag) is formed into a layer having a film thickness of 50 to 200 nm by means such as vapor deposition to obtain the second electrode 6 serving as a cathode (FIG. 3). (See (d)). The second electrode 6 is connected to an electrode portion 6 b provided on one side of the support substrate 2.

  Next, the sealing member 7 having the recess 7a and the support 7b is hermetically disposed on the support substrate 2 via the adhesive 8 made of, for example, an ultraviolet curable epoxy resin. The organic EL element 1 is sealed with the sealing member 7 and the support substrate 2 (see FIG. 3E). At this time, the sealing member 7 is disposed on the support substrate 2 so that the electrode portion 3c of the first electrode 3 and the electrode portion 6b of the second electrode 6 are exposed to the outside.

  After forming the organic EL element 1 on the support substrate 2, the organic EL element 1 is heated to 50 ° C. or higher and 15 V or higher between the first and second electrodes 3 and 6 in a nitrogen atmosphere having a predetermined oxygen concentration. An energization process is performed in which a voltage of 1 is applied in the reverse bias direction. By the energization process, at least a portion of the back electrode that is in contact with the transparent electrode is removed and separated from the transparent electrode. Through the above steps, an organic EL panel having the organic EL element 1 is obtained. Note that the energization process is performed so that the chromaticity change amount with respect to the current density of the x-value and y-value of the CIE chromaticity coordinates of the organic EL element 1 to be described later is 0.02 or less after the energization process. This is performed by adjusting the heating temperature of the element 1 and the voltage application time.

  FIG. 4 is a diagram showing the relationship between the chromaticity of the display light and the current density before and after the energization process in the organic EL element 1 of the present embodiment. The energization process is the same as that performed for the conventional organic EL element in FIG. Further, the x value and y value of the CIE chromaticity coordinates in FIG. 4 indicate values when a predetermined reference value is set to zero. In FIG. 4A, the characteristic S1 indicates the relationship between the x value of the CIE chromaticity coordinates of the display light and the current density in the organic EL element 1 before the energization process, and the characteristic S2 is after the energization process. The relationship between the x value of the CIE chromaticity coordinate of the display light and the current density in the organic EL element 1 is shown. In FIG. 4B, a characteristic S3 indicates the relationship between the y value of the CIE chromaticity coordinates of the display light and the current density in the organic EL element 1 before the energization process, and the characteristic S4 indicates the organic EL element. 1 shows the relationship between the y value of the CIE chromaticity coordinates of the display light after the energization process 1 and the current density. As shown in FIG. 4A, the organic EL element 1 before the energization process is obtained when the chromaticity change amount Δx of the x value in the CIE chromaticity coordinates of the display light with respect to the current density, that is, the current density is changed. Although the difference between the maximum value and the minimum value of the x value of the CIE chromaticity coordinates of the display light is larger than 0.03, the organic EL element 1 after the energization process has the chromaticity change amount Δx with respect to the current density. Is 0.02 or less. Therefore, the organic EL element 1 after the energization process has substantially the same emission color when emitting light with a low current density and when emitting light with a high current density, and the user does not recognize the color change. It is possible to suppress it. The inventor of the present application improves the light emission efficiency of the light emitting layer having a long wavelength by performing the energization process in the organic EL element having a plurality of light emitting layers having different light emission wavelengths, and particularly the light emission luminance at the time of light emission driving with a low current density Has been found to be higher than before the energization treatment. On the other hand, the light emission efficiency of the short wavelength light emitting layer does not improve as much as that of the long wavelength light emitting layer even after the energization treatment, and the light emission luminance at the time of light emission driving at a low current density is the same as that of the long wavelength light emitting layer. Similarly, it will not be high. In the present embodiment, the second light emitting layer 5c that emits light having a shorter wavelength than the first light emitting layer 5b suppresses the chromaticity change amount of the display light with respect to the current density before the energization processing as in the conventional case. The amount of change in chromaticity of display light with respect to the current density after the energization treatment as described above is obtained by mixing a larger amount of the hole transporting material and improving the luminous efficiency of the second light emitting layer 5c in advance. It is possible to obtain the organic EL element 1 in which is suppressed.

  In the manufacturing method of the organic EL element 1 in the present embodiment, the organic layer 5 having at least the first and second light emitting layers 5 b and 5 c having different emission colors is sandwiched between the pair of first and second electrodes 3 and 6. The first and second light emitting layers 5b and 5c are formed so that the amount of change in chromaticity of the display light before the energization process with respect to the current density is greater than 0.02. And a step of performing an energization process of applying a predetermined voltage between the first and second electrodes 3 and 6 after the first and second electrodes 3 and 6 and the organic layer 5 are formed. It is. Further, the energization process is performed so that the chromaticity change amount of the display light with respect to the current density after the energization process is 0.02 or less. In the step of performing the energization process, a predetermined voltage is applied in the reverse bias direction between the first and second electrodes 3 and 6. Further, in the step of performing the energization process, the energization process is performed in a nitrogen atmosphere having a predetermined oxygen concentration. Further, in the step of performing the energization process, the energization process is performed by heating the organic EL element 1 including the organic layer 5 to 50 ° C. or more.

  With this manufacturing method, the organic EL element 1 has the chromaticity of the display light with respect to the current density before the energization process in order to cope with the change in the light emission efficiency of the first and second light emitting layers 5b and 5c by the energization process in advance. By setting the change amount Δx to be larger than 0.02, the chromaticity change amount Δx of the display light with respect to the current density after the energization process can be made 0.02 or less, and the current density due to the low current density can be reduced. Regardless of the value, the luminescent color obtained can be made substantially the same, and the change in the color of the display light can be suppressed to the extent that the user does not recognize it.

  When the hole transporting material is added to the first and second light emitting layers 5b and 5c, the energization treatment is performed depending on the concentration of the hole transporting material contained in the second light emitting layer 5c having a short emission wavelength. Corresponding to the change in the light emission efficiency of the first light emitting layer 5b, the light emission efficiency of which easily changes, the emission peak intensity of the second light emitting layer 5c, which is difficult to improve the light emission efficiency by the energization treatment, can be increased in advance. The amount of change in chromaticity of display light with respect to the current density before the energization process can be easily adjusted.

  In the present embodiment, the emission peak intensity of the second light emitting layer 5c is increased in advance according to the concentration of the hole transporting material contained in the second light emitting layer 5c having a short emission wavelength, before the energization treatment. The amount of change in chromaticity of the display light with respect to the current density is adjusted, but as another method, the energization is performed according to the film thickness of the second light emitting layer 5c having a short emission wavelength or the concentration of the second light emitting material. The amount of change in chromaticity of display light relative to the current density before processing may be adjusted, and the concentration of the hole transporting material, the thickness of the second light emitting layer 5c, and the second light emitting material. The amount of change in chromaticity of the display light with respect to the current density before the energization process may be adjusted by combining the densities of the above. Specifically, the thickness of the second light emitting layer 5c is made thinner than the conventional case where the chromaticity change amount of the display light with respect to the current density is 0.02 or less before the energization processing as in the prior art. The emission peak intensity of the second light emitting layer 5c can be made larger in advance than the blue light emitting layer of the conventional organic EL element. Further, the concentration of the second light-emitting material contained in the second light-emitting layer 5c is set to be lower than that in the case where the chromaticity change amount of the display light with respect to the current density is 0.02 or less before the energization processing as in the prior art. By making it higher, the emission peak intensity of the second light emitting layer 5c can be made larger in advance than the blue light emitting layer of the conventional organic EL element.

  In the present embodiment, the hole transporting material is added to the first and second light emitting layers 5b and 5c. However, the organic EL element includes a plurality of light emitting layers having different emission colors. When an electron transporting material such as aluminum quinolinol (Alq3) is added to each of the light emitting layers, the concentration of the electron transporting material in the light emitting layer having a short light emission wavelength among the light emitting layers, the organic EL element with respect to the current density before the energization treatment. The amount of change in chromaticity of display light may be adjusted. Specifically, when the concentration of the electron transporting material contained in the light emitting layer having a short emission wavelength is set to 0.02 or less of the chromaticity change amount of the display light with respect to the current density before the energization processing as in the past. The emission peak intensity of the light emitting layer having a short emission wavelength can be increased in advance, and the chromaticity change amount of the display light of the organic EL element with respect to the current density before the energization treatment is greater than 0.02. It becomes possible to adjust so that it becomes.

  Moreover, although this embodiment applied the manufacturing method of the organic EL element of this invention to the organic EL panel provided with the segment type organic EL element 1, the manufacturing method of the organic EL element of this invention is a dot matrix type organic EL. It can also be applied to elements. In addition, the organic EL panel according to the present embodiment is provided with the translucent first electrode 3 and takes out the light emitted from the organic EL element 1 from the support substrate 2 side to perform a predetermined display. The organic EL element manufacturing method includes a so-called top emission type organic EL panel in which the second electrode on the organic layer is formed of a light-transmitting conductive material, and a predetermined display is performed by taking out light from the sealing member side. It is also applicable to.

  In the present embodiment, the organic EL element 1 is configured to include two light emitting layers, the first and second light emitting layers 5b and 5c. However, the organic EL element in the present invention emits three or more layers. A layer may be provided.

The figure which shows the organic electroluminescent panel which is embodiment of this invention. The expanded sectional view which shows the organic layer of an organic EL element same as the above. The figure which shows the manufacturing process of an organic electroluminescent panel same as the above. The figure which shows the relationship between the chromaticity of the display light of an organic EL element same as the above, and current density. The figure which shows the relationship between the chromaticity of the display light of a conventional organic EL element, and current density.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Organic EL element 2 Support substrate 3 1st electrode 4 Insulating layer 5 Organic layer 5a Hole transport layer 5b 1st light emitting layer 5c 2nd light emitting layer 5d Electron transport layer 5e Electron injection layer 5f 3rd light emitting layer 5g 1st Four light emitting layers 6 Second electrode

Claims (4)

A method for producing an organic EL element, wherein an organic layer having at least a plurality of light emitting layers having different emission colors is sandwiched between a pair of electrodes,
A step of forming each light emitting layer so that the amount of change in chromaticity of display light with respect to the current density is greater than 0.02, and a predetermined voltage is applied between the electrodes after the formation of the electrodes and the organic layer. and performing energization processing for, Ri name contains at least a
In the step of forming each light emitting layer, each light emitting layer is formed by mixing a light emitting material with a host material, or each light emitting layer is mixed with a light emitting material with a host material, and further a hole transporting material or electron Formed by adding a transport material, the thickness of the light emitting layer having at least a short emission wavelength among the light emitting layers, the concentration of the light emitting material contained in the light emitting layer having at least a short emission wavelength among the light emitting layers, The concentration of the hole transporting material contained in the light emitting layer having a short emission wavelength among the light emitting layers, the concentration of the electron transporting material contained in the light emitting layer having a short emission wavelength among the light emitting layers, or these By adjusting the amount of change in chromaticity of the display light with respect to the current density,
In the step of performing the energization processing, performs the energization processing by heating the organic layer over 50 ° C., Ru and remove a portion in contact with the other electrode of the one electrode is peeled from the other electrode The manufacturing method of the organic EL element characterized by the above-mentioned. 2. The method of manufacturing an organic EL element according to claim 1, wherein the energization process is performed such that a chromaticity change amount of the display light with respect to a current density after the energization process is 0.02 or less. 2. The method of manufacturing an organic EL element according to claim 1, wherein, in the step of performing the energization process, a predetermined voltage is applied between the electrodes in a reverse bias direction. 2. The method of manufacturing an organic EL element according to claim 1, wherein in the step of performing the energization process, the energization process is performed in a nitrogen atmosphere having a predetermined oxygen concentration.

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