JP2012038441A - Light emitting device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To solve the problem that a light emitting device which has an organic light emitting layer between a transparent electrode layer and a metal electrode layer decreases in contrast as ambient light is reflected on the metal electrode layer to decrease in visibility of an image, and a pattern of the metal electrode layer is thereby recognized.SOLUTION: The light emitting device includes a light-transmissive lower electrode layer 11 provided on a light-transmissive substrate 19, an organic light emitting layer 12 provided on the light-transmissive lower electrode layer, and an upper electrode layer 13 provided on the organic light emitting layer. The upper electrode layer contains a pigment. Consequently, the pigment of the upper electrode layer absorbs or scatters ambient light reflected on the upper electrode layer, so the reflectance of the ambient light reflected on the upper electrode layer decreases. As a result, the intensity of light in a light emitting area of the organic light emitting layer in non-emission state can be decreased.

Description

  The present invention relates to a light emitting device related to a display panel and the like, and more particularly to a light emitting device using an organic light emitting layer.

In recent years, display devices using organic electroluminescent elements (hereinafter referred to as organic EL elements) are used in various electronic devices such as mobile phones, computers, electronic notebooks, and portable game machines. For this reason, the user has more opportunities to view not only the display device of the electronic device indoors but also the display device outdoors. In general, an organic EL device has a structure in which an organic light emitting layer is sandwiched between a transparent electrode layer and a metal electrode layer on a transparent substrate. It is known that the light is reflected on the metal electrode layer, and as a result, the contrast between the light emitting region and the non-light emitting region of the organic light emitting layer is lowered and the image visibility is deteriorated. In addition, in the case of a display device that displays a certain pattern by forming the metal electrode layer in a pattern, the light emitting region pattern of the organic light emitting layer is reflected by the reflection of the metal electrode layer by external light even when the light emitting region of the organic light emitting layer is not emitting light. There was also a problem of being visually recognized.

Therefore, in order to improve the contrast and make the pattern of the metal electrode layer invisible when the light emitting region of the organic light emitting layer is not emitting light (hereinafter referred to as pattern camouflaging), as a conventional technique, (1) (1) A color filter provided on the surface of the transparent substrate on the light exit surface side (for example, Japanese Patent Application Laid-Open No. 10-321143), (2) An anti-reflection means provided on the sealing cover on the light exit surface side ( For example, Japanese Patent Laid-Open No. 2001-230072), (3) a light polarizing plate provided with a circularly polarizing plate (for example, Japanese Patent Laid-Open No. 8-321381), and (4) the opposite side of the light emitting surface side of the metal electrode layer. (5) A conductive black layer provided on the light emission surface side of the metal electrode layer (for example, a special feature). No. 2005-310799 Broadcast), and the like are known.

JP-A-10-32143 Japanese Patent Laid-Open No. 2001-230072 Japanese Patent Laid-Open No. 8-322138 JP 2002-532830 A JP 2005-310799 A

However, in the prior arts (1), (2), and (3), the influence of contrast reduction due to external light is reduced and the pattern is camouflaged, but the original output from the organic light emitting layer is possible. There has been a problem that the light intensity of the image is reduced, and the brightness of the entire screen is greatly reduced. Furthermore, the prior art (3) has a problem that an expensive circularly polarizing plate must be used. In the prior art (4), the reflection of external light by the metal electrode layer can be reduced. However, since the light absorption layer is provided on the back side of the metal electrode layer on the light emission surface side, the effect is significant. In addition, the material and thickness of the metal electrode layer are greatly limited.

Further, in the prior art (5), as in the display panel 900 shown in FIG. 10, the light emitting polymer light emitting layer 905 sandwiched between the metal electrode 902 on the substrate 901 and the transparent conductive film 906 has a metal structure. A black layer 911 formed of a carbon allotrope having conductivity is provided on the light emission surface side of the electrode 902 to prevent reflection of light from the metal electrode 902. In addition, a hole injecting and transporting layer 903 for injecting holes into the light emitting layer 905 is further provided between the black layer 911 and the light emitting layer 905.

In the prior art of (5), unlike the prior art of (4), since the black layer 911 is provided on the reflective surface side of the metal electrode 902, the antireflection effect is higher than that of the prior art of (4). . However, since the black layer 911 is provided in the configuration related to the light emission of the organic EL element, the hole injection transport layer 903 must be further provided, and the influence on the light emitting layer 905 is reduced. The black layer should be DLC (Diamond Like Carbon) and thinner. For this reason, there is a problem that it is difficult to form a DLC film or a thinner layer, so that the antireflection effect is lowered.

  SUMMARY OF THE INVENTION The present invention solves the above-described problems. The present invention greatly improves the decrease in contrast due to outside light without causing a decrease in the brightness of the original image, improves visibility, and makes the pattern camouflage. It is an object to provide a light emitting device using an organic light emitting layer.

In order to solve this problem, a light-emitting device of the present invention includes a light-transmitting lower electrode layer that transmits visible light and is provided on a light-transmitting substrate that transmits visible light that has a wavelength in the visible region. And an organic light emitting layer provided on the light transmissive lower electrode layer, and an upper electrode layer provided on the organic light emitting layer, wherein the upper electrode layer contains a pigment. It is characterized by that.
According to this, since the light emitting device of the present invention absorbs or scatters the external light applied to the upper electrode layer by the pigment of the upper electrode layer, the reflectance of the external light applied to the upper electrode layer decreases, The intensity of light in the light emitting region of the organic light emitting layer when not emitting light can be reduced. As a result, the contrast between the light emitting area and the non-light emitting area of the light emitting region of the organic light emitting layer is increased and visibility can be improved without significantly reducing the brightness as in the prior art. Furthermore, the contrast between the light emitting region and the non-light emitting region of the organic light emitting layer is reduced, and the pattern can be camouflaged.

The light emitting device of the present invention is characterized in that the upper electrode layer contains a binder resin and a conductive member.

According to this, since the light emitting device of the present invention uses a composite film that is not a metal film for the upper electrode layer, it can scatter the external light applied to the upper electrode layer and reduce the reflectance. The light intensity of the light emitting region of the organic light emitting layer during light emission can be reduced. As a result, the contrast between the light emitting area and the non-light emitting area of the light emitting region of the organic light emitting layer is increased without significantly reducing the brightness as in the prior art, and the visibility can be greatly improved. Furthermore, the contrast between the light emitting region and the non-light emitting region of the organic light emitting layer is reduced, and the pattern is more camouflaged.

In order to solve this problem, a light emitting device of the present invention is provided with a lower electrode layer provided on a substrate, an organic light emitting layer provided on the lower electrode layer, and the organic light emitting layer. A light-transmitting upper electrode layer that transmits visible light that is light having a wavelength in the visible region, and the lower electrode layer contains a pigment.

According to this, since the light emitting device of the present invention absorbs or scatters the external light applied to the upper electrode layer by the pigment of the lower electrode layer, the reflectance of the external light applied to the lower electrode layer decreases, The intensity of light in the light emitting region of the organic light emitting layer when not emitting light can be reduced. As a result, the contrast between the light emitting area and the non-light emitting area of the light emitting region of the organic light emitting layer is increased and visibility can be improved without significantly reducing the brightness as in the prior art. Furthermore, the contrast between the light emitting region and the non-light emitting region of the organic light emitting layer is reduced, and the pattern can be camouflaged.

  The light emitting device of the present invention is characterized in that the lower electrode layer contains a binder resin and a conductive member.

According to this, since the light emitting device of the present invention uses a composite film that is not a metal film for the lower electrode layer, it can scatter the external light applied to the lower electrode layer and reduce the reflectance. The light intensity of the light emitting region of the organic light emitting layer during light emission can be reduced. As a result, the contrast between the light emitting area and the non-light emitting area of the light emitting region of the organic light emitting layer is increased without significantly reducing the brightness as in the prior art, and the visibility can be greatly improved. Furthermore, the contrast between the light emitting region and the non-light emitting region of the organic light emitting layer is reduced, and the pattern is more camouflaged.

  The light emitting device of the present invention is characterized in that the material of the pigment contains carbon.

According to this, when carbon is included, the pigment becomes black, the upper electrode layer and the lower electrode layer containing the pigment have a black hue, and light applied from outside the upper electrode layer and the lower electrode layer is irradiated. It is absorbed and the reflectance of these electrode layers can be reduced. As a result, the light intensity of the light emitting region of the organic light emitting layer when not emitting light can be reduced, so that the contrast between the light emitting region and the light emitting region of the organic light emitting layer is increased and visibility is further improved. be able to. Further, the contrast between the light emitting region and the non-light emitting region of the organic light emitting layer is reduced, and the pattern is further camouflaged.

The light-emitting device of the present invention is characterized in that the conductive member contains nanoparticulate silver.

According to this, since the upper electrode layer and the lower electrode layer are conductive films made of nanoparticulate silver, the surface roughness of the film is reduced, and the surface of the upper electrode layer or the lower electrode layer is smoothed. The thickness of the organic light emitting layer provided under the upper electrode layer or on the lower electrode layer can be reduced. This makes it possible to reduce the energy loss by reducing the movement distance of electrons and holes in the organic light emitting layer, and increase the light emission efficiency.

The light-emitting device of the present invention is characterized in that a ratio of the carbon contained in the upper electrode layer and the lower electrode layer is 5 wt% or more and 10 wt% or less.

According to this, since the upper electrode layer and the lower electrode layer are made so that carbon is 5% by weight or more, the upper electrode layer and the lower electrode layer containing carbon are colored in black, and the upper electrode layer and Light applied from outside the lower electrode layer is absorbed, and the reflectance of these electrode layers can be reduced. In addition, since the upper electrode layer and the lower electrode layer are made so that the carbon content is 10% by weight or less, the conductivity of the upper electrode layer and the lower electrode layer is not significantly lowered, so that the emission luminance of the organic light emitting layer is greatly increased. There is no lowering. As a result, while preventing a decrease in light emission luminance, the difference in light intensity between the light emitting region and the non-light emitting region of the organic light emitting layer can be increased, the contrast can be increased, and the pattern can be camouflaged. The visibility can be further greatly improved.

The light emitting device of the present invention is characterized in that the pigment reflects light in a wavelength region including a peak wavelength of light emission from the organic light emitting layer.

According to this, since the pigment is a similar color that reflects the emission color of the organic light emitting layer, the upper electrode layer and the lower electrode layer containing the pigment have a similar color shade. For this reason, the light from the light emitting region is visually recognized because the color of the upper electrode layer or lower electrode layer overlaps with the color of the organic light emitting layer. As a result, the organic light emitting layer is visually recognized without impairing the original color of the emitted light. By this, the quality of the luminescent color of an organic light emitting layer can be improved.

The light emitting device of the present invention is characterized in that the light transmissive upper electrode layer is a transparent conductive polymer.

According to this, since the light transmissive upper electrode layer is a transparent conductive polymer, the light transmissive upper electrode layer is formed by wet coating the transparent conductive polymer, and drying and solidifying in dry air. be able to. By this, since the surface of the organic light emitting layer is not damaged by low temperature treatment and sputtering, the light emitting efficiency of the organic light emitting layer is not lowered.

According to this, the light emitting device of the present invention absorbs or scatters external light applied to the upper electrode layer and the lower electrode layer because the pigment of the upper electrode layer and the lower electrode layer absorbs or scatters the external light. The reflectance of the external light applied decreases, and the difference in light intensity between when the light emitting region of the organic light emitting layer emits light and when it does not emit light increases. As a result, the contrast is increased, the visibility is improved, and the camouflage of the pattern is also achieved, so that the visibility can be greatly improved. Therefore, the light-emitting device of the present invention can greatly improve the decrease in contrast due to external light, improve visibility, and make the pattern camouflage without causing a significant decrease in luminance as in the past. Provided is a light emitting device using an organic light emitting layer.

It is a figure explaining the structure of the light-emitting device of 1st Embodiment of this invention, Fig.1 (a) is the perspective view, FIG.1 (b) is the II line | wire shown to Fig.1 (a). FIG. It is a part of light-emitting device of 1st Embodiment of this invention, Comprising: It is a block diagram for demonstrating the structure of an upper electrode layer. It is a block diagram explaining the difference with dye about the pigment contained in the upper electrode layer of the light-emitting device of 1st Embodiment of this invention. It is a figure explaining the structure of the light-emitting device of 2nd Embodiment of this invention, Fig.4 (a) is the perspective view, FIG.4 (b) is the IV-IV line | wire shown to Fig.4 (a). FIG. It is a part of light-emitting device of 2nd Embodiment of this invention, Comprising: It is a block diagram for demonstrating the structure of a lower electrode layer. It is a figure explaining the structure of the light-emitting device of 3rd Embodiment of this invention, Fig.6 (a) is the perspective view, FIG.6 (b) is VI-VI line | wire shown to Fig.6 (a). FIG. It is a figure explaining the structure of the light-emitting device of 4th Embodiment of this invention, Fig.7 (a) is the perspective view, FIG.7 (b) is the VII-VII line | wire shown to Fig.7 (a). FIG. It is a top view explaining the light-emitting device of 5th Embodiment of this invention. It is a perspective view explaining the structure of the light-emitting device panel using the light-emitting device of 6th Embodiment of this invention. It is sectional drawing of a part of display panel shown by the prior art example (5). It is a photograph for demonstrating the nanoparticulate silver of the light-emitting device of 3rd Embodiment of this invention, Comprising: It is an electron micrograph of a silver nanoparticle.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

[First Embodiment]
FIG. 1 is a diagram for explaining the configuration of the light emitting device 111 according to the first embodiment of the present invention, FIG. 1 (a) is a perspective view thereof, and FIG. 1 (b) is shown in FIG. 1 (a). It is sectional drawing of the II line shown. In FIG. 1, the actually provided sealing layer is omitted.

In the light emitting device 111 according to the first embodiment of the present invention, as shown in FIG. 1, a light transmissive lower electrode layer 11 is provided on a light transmissive substrate 19, and an organic light emitting layer 12 is provided between the upper electrode layer 13. It is arranged. Then, by supplying current to the upper and lower electrode layers, the organic light emitting layer 12 emits light, and light from the entire light emitting area LA is directed downward DW, the light transmissive lower electrode layer 11 and the light transmissive substrate 19. And is visually recognized as emitted light of the light emitting device 111 (hereinafter referred to as a bottom emission type). The light emitting area LA shown in FIG. 1A is shown in a semicircular shape, but the shape of the light emitting area LA is not particularly limited to a semicircular shape, but is a circle, an ellipse, a rectangle such as a triangle, a rectangle, a square, or a polygon. It can also be made into a shape. In order to improve environmental resistance, a sealing layer is provided on the upper electrode layer 13 and the organic light emitting layer 12 (not shown), and a portion surrounded by the bank (sealing wall) 202 is sealed. Yes.

As the light-transmitting substrate 19, a rigid substrate such as a glass substrate or a synthetic resin substrate, or a film substrate such as a plastic film is used. In particular, since it has flexibility, a plastic film is preferably used. As the resin material of the plastic film or the synthetic resin substrate, resins such as PET (polyethylene terephthalate), PEN (polyethylene naphthalate), PP (polypropylene), PS (polystyrene), acrylic, polyimide, polyaramid, and the like are used. Among these, PET or PEN is particularly preferably used in terms of transparency, flexibility, and heat resistance. Further, the light transmissive substrate 19 having a thickness of about 100 μm is preferably used.

The light transmissive lower electrode layer 11 is preferably made of an inorganic transparent conductive material such as indium oxide-tin oxide (ITO). After the film is formed by a film forming method such as sputtering, photolithography and wet etching are used. And patterned into a pattern. In addition, the light transmissive lower electrode layer 11 can be formed by wet coating a light transmissive conductive polymer.

As the organic light emitting material of the organic light emitting layer 12, any material can be suitably used as long as it is used as a so-called organic EL (electroluminescence) material that emits light by an external electric field. Among these, a high molecular weight light emitting material is preferable because it can be printed as a solution, but a low molecular weight material may be used, or a high molecular weight material and a low molecular weight material may be mixed and used. For example, polyvinyl carbazole (PVK), which is a high molecular weight hole transporting material, and low molecular weight 2,5-bis (1-naphthyl) -1,3,4-oxadiazole (BND) (electron transporting material) And 3- (2′-benzothiazolyl) -7-diethylaminocoumarin (coumarin-6) (which is a luminescent material) can be used in combination. After printing, it is preferable to dry in dry air.

The banks (sealing walls) 202 provided on the light transmissive lower electrode layer 11 and the light transmissive substrate 19 are formed by screen printing. The material of the bank (sealing wall) 202 is not particularly limited as long as it has insulating properties, but a resin that can be printed is preferable, and a thermosetting resist used particularly for semiconductor manufacturing is preferable. Used for. There is no problem even if the bank (sealing wall) 202 is not transparent. However, when a transparent material is used, light from the light emitting layer, particularly light emitted in the lateral direction, passes through the inside of the bank (sealing wall) 202. Therefore, the amount of light emitted from the light emitting device 111 can be increased.

In FIG. 1, the bank (sealing wall) 202 is preferably formed by screen printing. However, the printing / coating technique is not limited to screen printing, and printing / coating such as spin coater, inkjet, gravure printing, roll coater, etc. A coating technique can also be suitably used. It is also possible to form the bank (sealing wall) 202 with a photo-curing resist layer and form it into a wall shape by development and etching processes. It is not limited to technology. Further, the height of the bank (sealing wall) 202 is substantially the same as or slightly higher than that obtained by stacking the light emitting structures formed inside, and in the present invention, the height of the bank (sealing wall) 202 is It was set to 1 to 20 μm.

FIG. 2 is a configuration diagram for explaining the configuration of the upper electrode layer 13 which is a part of the light emitting device 111 according to the first embodiment of the present invention. As shown in FIG. 2, the upper electrode layer 13 is composed of a layer having a pigment 14, a binder resin 15, and a conductive member 16, and the pigment 14 and the conductive member 16 are dispersed or dispersed in a matrix of the binder resin 15. It exists by forming a chain structure. The upper electrode layer 13 is produced by printing a conductive ink having a pigment 14, a binder resin 15, and a conductive member 16 on a screen plate, and drying and solidifying the conductive ink. The thickness of the upper electrode layer 13 is 1 to 50 μm, particularly 5 to 15 μm, and 10 μm is particularly preferable.

The pigment 14 is an inorganic pigment such as carbon, iron oxide, procyan blue, ultramarine blue, or the like, or an organic pigment such as phthalocyanine, anthraquinone, indigo, nitroso, violanthrone, xanthene, A wide variety of pigments such as isoindoline type are used. In particular, since carbon such as carbon black is a black pigment, if the carbon is included, the pigment becomes black, and the upper electrode layer 13 containing the pigment 14 has a black hue and is applied from outside the upper electrode layer 13. The absorbed light is absorbed, and the reflection of light by the upper electrode layer 13 can be reduced. Therefore, carbon such as carbon black is preferably used as the pigment 14.

Table 1 shows the result of using carbon black as the pigment 14 of the upper electrode layer 13 and changing the mixing ratio of carbon black at that time. Example 1, Example 2 and Example 3 in Table 1 show the results of changing the mixing ratio of carbon black, and Comparative 1 shows a conventional example in which no carbon black is added. In addition, Example 3 could not be evaluated because it did not emit light. As shown in Table 1, if the ratio of carbon contained in the upper electrode layer 13 is 5% by weight or more and 10% by weight or less, the electrode color becomes gray, and the light emission luminance is not greatly reduced, and the visibility is reduced. And the pattern can be camouflaged. However, if the proportion of carbon contained in the upper electrode layer 13 is within 5% by weight, the emission luminance is not lowered, but the visibility is poor and the pattern cannot be camouflaged. On the other hand, if the proportion of carbon contained in the upper electrode layer 13 is 20% by weight or more, the pattern is camouflaged, but no light is emitted. Thus, the proportion of carbon contained in the upper electrode layer 13 is preferably 5% by weight or more and 10% by weight or less.

Table 2 shows an example in which copper phthalocyanine green is used as another pigment of the upper electrode layer 13 (Example 4). When carbon black in Table 1 is used (Example 1), the pigment is The result of comparing the conventional case not used at all with (Comparison 1) is shown. As shown in Table 2, the ratio of the copper phthalocyanine green contained in the upper electrode layer 13 is 5% by weight, and the electrode color is light green. Can be improved and the pattern can be camouflaged.

Further, it is conceivable to use a dye having a coloring action similar to that of a pigment. However, as shown in FIG. 3B (the conductive member 16 is not shown), when the dye 214 is used, the solvent is dried. Occasionally, the dye 214 is segregated at the boundary portion on the organic light emitting layer 12 side, which causes a problem that electron injection from the electrode layer 213 is hindered. Further, even when the electrode layer 213 containing the dye 214 is formed by a method such as vapor deposition, the dye 214 is segregated at the boundary portion on the organic light emitting layer 12 side in the same manner, There arises a problem that the electron injection is hindered. On the other hand, when the pigment 14 is used, as shown in FIG. 3A (the conductive member 16 is not shown), the pigment 14 can be uniformly dispersed in the matrix of the binder resin 15. There is no hindrance to electron injection.

As the binder resin 15 shown in FIG. 2, a polyester resin, a polyethylene resin, a polyurethane resin, or the like can be used, but any resin that is suitable for printing can be suitably used. The conductive member 16 shown in FIG. 2 is made of metal particles such as gold, silver, copper, platinum, aluminum, nickel, indium, yttrium, hafnium, zirconium, magnesium, manganese, vanadium, titanium, iron, and tungsten. Are preferably used. In particular, since the upper electrode layer 13 preferably uses an element having a low work function for injecting electrons, the conductive member 16 is preferably made of silver as an element having a low work function in the air. Further, when 0.01 to 3.0% by weight of a compound comprising an alkali metal and a compound comprising an alkaline earth metal, or an alkali metal or alkaline earth metal salt is added to silver, the upper electrode layer The work function of 13 is 4.21 to 4.49 eV, which is more preferable.

The supply of current to the light transmissive lower electrode layer 11 and the upper electrode layer 13 for causing the organic light emitting layer 12 to emit light is connected to the light transmissive lower electrode layer 11 via the extraction electrode 206 as shown in FIG. The lead electrode 207 and the lead electrode 208 connected to the upper electrode layer 13 are used. In FIG. 1, the extraction electrode 206 and the lead electrode 207 are formed separately in order to reduce the contact resistance with the light transmissive lower electrode layer 11, but they may be formed in the same layer.

The extraction electrode 206, the lead electrode 207, and the lead electrode 208 are made of the same type of binder resin and conductive member as the upper electrode layer 13, and are formed by a screen printing method or the like. The extraction electrode 206 is formed so as to overlap only a part of the light transmissive lower electrode layer 11 so as not to hinder the light transmission area in the light transmissive lower electrode layer 11 and lead to the outside of the light emitting region LA. I have to. Further, the extraction electrode 206, the lead electrode 207, and the lead electrode 208 may be a metal film or the like as long as they have conductivity, but a composite made of a binder resin and a conductive member similar to the upper electrode layer 13. By using a film, the manufacturing process can be simplified and the equipment can be shared. Therefore, it is more preferable to use a composite film.

As described above, in the light emitting device 111 according to the first embodiment of the present invention, since the upper electrode layer 13 contains the pigment 14, the pigment 14 in the upper electrode layer 13 is replaced with the light-transmitting substrate 19 and the light-transmitting lower portion. Since the external light applied to the upper electrode layer 13 through the electrode layer 11 and the organic light emitting layer 12 is absorbed or scattered, the reflectance of the external light applied to the upper electrode layer 13 is reduced, and the light is not emitted. The intensity of reflected light from the light emitting region LA of the organic light emitting layer 12 can be reduced. As a result, the contrast between the light emitting area LA and the non-light emitting area of the organic light emitting layer 12 is increased and visibility can be improved without causing a significant decrease in luminance as in the prior art. Furthermore, the contrast between the light emitting area LA and the non-light emitting area NL of the organic light emitting layer 12 is reduced, and the pattern can be camouflaged.

Since the upper electrode layer 13 contains the binder resin 15 and the conductive member 16, a composite film that is not a metal film is used for the upper electrode layer 13, so that the upper electrode layer 13 was applied to the upper electrode layer 13. It is possible to scatter outside light and reduce the reflectance, and to reduce the intensity of reflected light of the light emitting region LA of the organic light emitting layer 12 when not emitting light. As a result, the contrast of the light emitting area LA of the organic light emitting layer 12 when light is emitted and when the light is not emitted is increased without significantly reducing the luminance as in the conventional case, and the visibility can be greatly improved. Furthermore, the contrast between the light emitting area LA and the non-light emitting area NL of the organic light emitting layer 12 is reduced, and the pattern is camouflaged.

The material of the pigment 14 included in the upper electrode layer 13 includes carbon. If the material includes carbon, the pigment becomes black, and the upper electrode layer 13 including the pigment 14 has a black color. The light applied from the outside of the upper electrode layer 13 is absorbed, and the reflectance of the upper electrode layer 13 can be reduced. As a result, the intensity of the reflected light of the light emitting area LA of the organic light emitting layer 12 when not emitting light can be reduced, so that the contrast between the light emitting area LA of the organic light emitting layer 12 and the light emitting area LA increases, and visibility is improved. This can be greatly improved. Furthermore, the contrast between the light emitting area LA and the non-light emitting area NL of the organic light emitting layer 12 is reduced, and the pattern is further camouflaged.

In addition, since the upper electrode layer 13 is formed such that the ratio of carbon contained in the upper electrode layer 13 is 5% by weight or more, the upper electrode layer 13 containing carbon has a blackish color, and the upper electrode layer Light applied from outside 13 is absorbed, and the reflectance can be reduced. In addition, since the upper electrode layer 13 is formed so that the proportion of carbon contained in the upper electrode layer 13 is 10% by weight or less, the conductivity of the upper electrode layer 13 is not significantly lowered. The light emission brightness of is not greatly reduced. As a result, it is possible to increase the difference in light intensity between when the light emitting area LA of the organic light emitting layer 12 emits light and when it does not emit light while preventing a decrease in light emission luminance, thereby increasing the contrast and making the pattern camouflaged. Therefore, the visibility can be further greatly improved.

[Second Embodiment]
4A and 4B are diagrams for explaining the configuration of the light emitting device 121 according to the second embodiment of the present invention. FIG. 4A is a perspective view thereof, and FIG. 4B is a diagram shown in FIG. It is sectional drawing of the IV-IV line shown. Moreover, in FIG. 4, the sealing layer actually provided is abbreviate | omitted and described. In addition, the same member as 1st Embodiment has attached | subjected the same code | symbol, and abbreviate | omits description.

As shown in FIG. 4, the light emitting device 121 according to the second embodiment of the present invention is provided with an extraction electrode 226 on a substrate 29, and further provided with a lower electrode layer 27 on the extraction electrode 226, thereby transmitting a light transmissive upper electrode layer. The organic light emitting layer 22 is disposed between the organic light emitting layer 22 and the organic light emitting layer 22. Then, by supplying current to the upper and lower electrode layers, the organic light emitting layer 22 emits light, and light from the entire light emitting region LA passes through the light transmissive upper electrode layer 28 in the upward direction UP and passes through the light transmissive upper electrode layer 28. (Hereinafter referred to as the top emission type). As in the first embodiment, the light emitting area LA shown in FIG. 4A is shown in a semicircular shape, but the shape of the light emitting area LA is not particularly limited to a semicircular shape, and may be a circle, an ellipse, a triangle, a rectangle, It can also be a quadrangle such as a square, or a polygonal shape. In order to improve environmental resistance, a sealing layer (not shown) is provided on the light transmissive upper electrode layer 28 to seal a portion surrounded by the bank (sealing wall) 222.

As the substrate 29, a rigid substrate such as a glass substrate or a synthetic resin substrate, or a film substrate such as a plastic film is used. In particular, since it has flexibility, a plastic film is preferably used. As the resin material for the plastic film or the synthetic resin substrate, resins such as PET (polyethylene terephthalate), PEN (polyethylene naphthalate), PP (polypropylene), PS (polystyrene), acrylic (PMMA), polyimide, polyaramid, and the like are used. Among these, PET or PEN is particularly preferably used in terms of flexibility and heat resistance. The substrate 29 having a thickness of about 100 μm is preferably used.

FIG. 5 is a configuration diagram for explaining the configuration of the lower electrode layer 27, which is a part of the light emitting device 121 according to the second embodiment of the present invention. As shown in FIG. 5, the lower electrode layer 27 is composed of a layer having a pigment 24, a binder resin 25, and a conductive member 26, like the upper electrode layer 13 of the first embodiment. The member 26 exists in a dispersed or chain structure in the matrix of the binder resin 25. The lower electrode layer 27 is produced by printing a conductive ink having a pigment 24, a binder resin 25, and a conductive member 26 on a screen plate, and drying and solidifying the conductive ink. The film thickness of the lower electrode layer 27 is 1 to 50 μm, particularly 5 to 15 μm, and 10 μm is particularly preferable.

The pigment 24 is an inorganic pigment such as carbon, iron oxide, procyan blue, ultramarine blue or the like, or an organic pigment such as phthalocyanine, anthraquinone, indigo, nitroso, violanthrone, xanthene, A wide variety of pigments such as isoindoline type are used. In particular, since carbon such as carbon black is a black pigment, if the carbon is included, the pigment becomes black, and the lower electrode layer 27 containing the pigment 24 has a black hue and is applied from the outside of the lower electrode layer 27. The absorbed light is absorbed, and reflection of light by the lower electrode layer 27 can be reduced. Therefore, carbon such as carbon black is particularly preferably used for the pigment 24.

Further, since the lower electrode layer 27 has the same configuration as the upper electrode layer 13 of the first embodiment, when carbon black is used as the pigment 24 of the lower electrode layer 27, the results shown in Table 1 are the same. Result. That is, if the proportion of carbon contained in the lower electrode layer 27 is 5% by weight or more and 10% by weight or less, the light emission luminance is not significantly reduced, the visibility is improved, and the pattern can be camouflaged. The proportion of carbon contained in the lower electrode layer 27 is preferably 5 wt% or more and 10 wt% or less.

As the binder resin 25, a polyester resin, a polyethylene resin, a polyurethane resin, or the like can be used, but any resin that is suitable for printing can be suitably used. The conductive member 26 is preferably made of metal particles such as gold, silver, copper, platinum, aluminum, nickel, indium, yttrium, hafnium, zirconium, magnesium, manganese, vanadium, titanium, iron, and tungsten. . In particular, since the lower electrode layer 27 preferably uses an element having a low work function for injecting electrons, the conductive member 26 preferably uses silver as an element having a work function lower than that of other metal particles. It is done. Further, when 0.01 to 3.0 wt% of a compound made of an alkali metal and a compound made of an alkaline earth metal, or an alkali metal or alkaline earth metal salt is added to silver, the lower electrode layer The work function of 27 is 4.21 to 4.49 eV, which is more preferable.

Also, the organic light emitting material of the organic light emitting layer 22 shown in FIG. 4 may be used as a so-called organic EL (electroluminescence) material that emits light by an external electric field, like the organic light emitting layer 12 of the first embodiment. Any material can be suitably used. Among these, a high molecular weight light emitting material is preferable because it can be printed as a solution, but a low molecular weight material may be used, or a high molecular weight material and a low molecular weight material may be mixed and used. For example, polyvinyl carbazole (PVK), which is a high molecular weight hole transporting material, and low molecular weight 2,5-bis (1-naphthyl) -1,3,4-oxadiazole (BND) (electron transporting material) And 3- (2′-benzothiazolyl) -7-diethylaminocoumarin (coumarin-6) (which is a luminescent material) can be used in combination. After printing, it is preferable to dry in dry air.

The light transmissive upper electrode layer 28 is more preferably formed by wet coating a transparent conductive polymer. That is, the light transmissive upper electrode layer 28 is coated on the organic light emitting layer 22 with a transparent conductive polymer solution using an inkjet or a dispenser, more preferably a tubing dispenser, and dried in dry air. It is produced by solidifying. Further, a dopant may be added to the transparent conductive polymer. The film thickness of the light transmissive upper electrode layer 28 is preferably 100 to 700 nm. If the film thickness is smaller than 100 nm, the voltage applied to the organic light emitting layer 22 is not sufficient, and if the film thickness is larger than 700 nm, the light emission from the organic light emitting layer 22 becomes weak. More preferably, it is 200-500 nm.

The transparent conductive polymer is not particularly limited as long as it has conductivity and is a transparent polymer, but poly-3,4-ethylenedioxythiophene (hereinafter referred to as PEDOT) is particularly preferably used. When PEDOT is used for the conductive polymer, it is preferable to use polystyrene sulfonic acid (PPS) as a dopant.

The light transmissive upper electrode layer 28 is preferably made of a transparent conductive polymer, but, like the light transmissive lower electrode layer 11 of the first embodiment, an inorganic material such as indium oxide-tin oxide (ITO). A transparent conductive material can also be used. However, it is necessary to devise a film forming method such as vapor deposition or a patterning method using masking at the time of film forming so as not to damage the organic light emitting layer 22.

The bank (sealing wall) 222 provided on the substrate 29 and the extraction electrode 226 is formed by screen printing in the same manner as the bank (sealing wall) 202 of the first embodiment. The material of the bank (sealing wall) 222 is not particularly limited as long as it has an insulating property, but a resin that can be printed is preferable, and a thermosetting resist used particularly for semiconductor manufacturing is preferable. Used for. There is no problem even if the bank (sealing wall) 222 is not transparent, but if a transparent material is used, light from the light emitting layer, particularly light emitted in the lateral direction, passes through the inside of the bank (sealing wall) 222. Therefore, the amount of light emitted from the light emitting device 121 can be increased.

As shown in FIG. 4, the supply of current to the lower electrode layer 27 and the light-transmissive upper electrode layer 28 for causing the organic light-emitting layer 22 to emit light is performed by the extraction electrode 226 connected to the lower electrode layer 27 and the light-transmissive property. This is performed with the lead electrode 228 connected to the upper electrode layer 28. The extraction electrode 226 and the lead electrode 228 are made of the same kind of binder resin and conductive member as the lower electrode layer 27, and are formed by a screen printing method or the like. The lead electrode 228 is formed so as to overlap only a part of the light transmissive upper electrode layer 28 so as not to hinder the light transmission area in the light transmissive upper electrode layer 28 and lead outside the light emitting region LA. I have to. The extraction electrode 226 and the lead electrode 228 may be a metal film or the like as long as it has conductivity, but a composite film made of a binder resin and a conductive member similar to the lower electrode layer 27 is used. As a result, the manufacturing process can be simplified and the equipment can be shared, which is more preferable.

As described above, in the light emitting device 121 according to the second embodiment of the present invention, since the lower electrode layer 27 contains the pigment 24, the pigment 24 in the lower electrode layer 27 is converted into the light transmissive upper electrode layer 28, the organic light emission. Since the external light applied to the lower electrode layer 27 through the layer 22 is absorbed or scattered, the reflectance of the external light applied to the lower electrode layer 27 is reduced, and the organic light emitting layer 22 emits light when no light is emitted. The intensity of the reflected light in the area LA can be reduced. As a result, the contrast between the light emitting area LA and the non-light emitting area of the organic light emitting layer 22 is increased and visibility can be improved without causing a significant decrease in luminance as in the prior art. Further, the contrast between the light emitting area LA and the non-light emitting area NL of the organic light emitting layer 22 is reduced, and the pattern can be camouflaged.

Further, since the lower electrode layer 27 contains the binder resin 25 and the conductive member 26, a composite film that is not a metal film is used for the lower electrode layer 27, so that the lower electrode layer 27 was applied to the lower electrode layer 27. It is possible to scatter external light and reduce the reflectance, and to increase the difference in light intensity between when the light emitting area LA of the organic light emitting layer 22 emits light and when it does not emit light. The intensity of the reflected light of the light emitting area LA of the organic light emitting layer 22 when not emitting light can be reduced. As a result, the contrast between the light emitting area LA and the non-light emitting area of the organic light emitting layer 22 is increased without significantly reducing the luminance as in the conventional case, and the visibility can be greatly improved. Furthermore, the contrast between the light emitting area LA and the non-light emitting area NL of the organic light emitting layer 22 is reduced, and the pattern is more camouflaged.

  Further, the material of the pigment 24 included in the lower electrode layer 27 includes carbon, and when the material includes carbon, the pigment becomes black, and the lower electrode layer 27 including the pigment 24 has a black color, Light applied from the outside of the electrode layer 27 is absorbed, and the reflectance of the lower electrode layer 27 can be reduced. As a result, the intensity of the reflected light of the light emitting area LA of the organic light emitting layer 22 when not emitting light can be reduced, so that the contrast between the light emitting area LA of the organic light emitting layer 22 and the light emitting area LA increases, and visibility is improved. This can be greatly improved. Further, the contrast between the light emitting area LA and the non-light emitting area NL of the organic light emitting layer 22 is reduced, and the pattern is further camouflaged.

In addition, since the lower electrode layer 27 is formed such that the proportion of carbon contained in the lower electrode layer 27 is 5% by weight or more, the lower electrode layer 27 containing carbon has a blackish color, and the lower electrode layer The light applied from outside 27 is absorbed, and the reflectance can be reduced. In addition, since the lower electrode layer 27 is formed so that the proportion of carbon contained in the lower electrode layer 27 is 10% by weight or less, the conductivity of the lower electrode layer 27 is not significantly lowered, so that the organic light emitting layer 22 The light emission brightness of is not greatly reduced. As a result, it is possible to increase the difference in light intensity between the light emitting area LA and the non-light emitting area of the organic light emitting layer 22 while preventing a decrease in light emission luminance, to increase the contrast and to make the pattern camouflage. Therefore, the visibility can be further greatly improved.

Further, since the light transmissive upper electrode layer 28 is a transparent conductive polymer, the light transmissive upper electrode layer 28 is formed by wet coating the transparent conductive polymer, and drying and solidifying in dry air. be able to. By this, since the surface of the organic light emitting layer 22 is not damaged by low temperature treatment and sputtering, the light emitting efficiency of the organic light emitting layer 22 is not lowered.

Further, since the step of forming the lower electrode layer 27 can be taken before the formation of the organic light emitting layer 22, the process of the lower electrode layer 27 can be changed without worrying about damage to the organic light emitting layer 22. This makes it possible to devise processes such as adding additives to the lower electrode layer 27, making it a high temperature processing process, etc., further improving the visibility by the lower electrode layer 27, Simplification can be achieved.

[Third Embodiment]
6A and 6B are diagrams for explaining the configuration of the light emitting device 131 according to the third embodiment of the present invention. FIG. 6A is a perspective view thereof, and FIG. 6B is a diagram shown in FIG. It is sectional drawing of the VI-VI line shown. The light emitting device 131 of the third embodiment of the present invention is different from the light emitting device 111 of the first embodiment in that the upper electrode layer 33 is different from the upper electrode layer 13. In addition, the same member as 1st Embodiment has attached | subjected the same code | symbol, and abbreviate | omits description.

Similar to the upper electrode layer 13 of the first embodiment, the upper electrode layer 33 is composed of a layer having the pigment 14, the binder resin 15, and a conductive member, but the upper electrode layer 33 is made of a conductive member. The difference lies in that all or at least a part is nanoparticulate silver NPG. The upper electrode layer 33 is present in a portion surrounded by the bank (sealing wall) 202 in which the pigment 14 and the conductive member are dispersed or formed in a chain structure in the matrix of the binder resin 15. Is formed. Nanoparticulate silver NPG is a combined body of silver nanoparticles AGP having a particle diameter of several tens of nm or less (less than 100 nm) shown in the electron micrograph of FIG. Therefore, since the upper electrode layer 33 containing nanoparticulate silver NPG, which is a combined body of silver nanoparticle AGPs, forms a very dense uniform layer, the surface roughness thereof is nanoparticulate silver. The surface roughness of the electrode layer not containing NPG is very small.

Nanoparticulate silver NPG can be produced by dispersing silver nanoparticle AGP in a solvent in which protective colloid is dissolved and drying at a predetermined temperature. The silver nanoparticle AGP is dispersed in a solvent in a state where the surface of the silver nanoparticle AGP is covered with a protective colloid. However, when the solvent and the protective colloid are removed by heating, the silver nanoparticle AGP is bonded to the nanoparticle AGP. It becomes particulate silver NPG. When metals such as silver are refined into nanometer-order nanoparticles, the reactivity is greatly enhanced and the particles can be bonded to each other even at room temperature. The protective colloid that is a dispersing agent for dispersing the silver nanoparticle AGP is preferably a comb block copolymer, and the particle size of the silver nanoparticle AGP is several tens of nm or less, more preferably an average particle size of about 20 nm or less or 10 nm. The following are preferred. Alcohol is preferably used as the solvent in which the silver nanoparticles AGP are dispersed, but ethylene glycol is more preferable among the alcohols.

As described above, in the light emitting device 131 according to the third embodiment of the present invention, since the conductive member included in the upper electrode layer 33 includes nanoparticulate silver NPG, the upper electrode layer 33 includes nanoparticulate silver. Since the conductive film is made of NPG, the surface roughness of the film is reduced, the surface of the upper electrode layer 33 can be smoothed, and the thickness of the organic light emitting layer 12 provided below the upper electrode layer 33 Can be made thinner. This makes it possible to reduce the movement distance of electrons and holes in the organic light emitting layer 12 to reduce energy loss and increase the light emission efficiency.

In addition, nanoparticulate silver NPG can also be applied to the lower electrode layer 27 of the light emitting device 121 of the second embodiment of the present invention. According to this, since the conductive member contained in the lower electrode layer contains nanoparticulate silver NPG, the lower electrode layer is a conductive film made of nanoparticulate silver NPG. The surface roughness is reduced, the surface of the lower electrode layer can be smoothed, and the thickness of the organic light emitting layer provided on the lower electrode layer can be reduced. This makes it possible to reduce the energy loss by reducing the movement distance of electrons and holes in the organic light emitting layer, and increase the light emission efficiency.

[Fourth Embodiment]
FIG. 7 is a diagram for explaining the configuration of a light emitting device 141 according to the fourth embodiment of the present invention, FIG. 7 (a) is a perspective view thereof, and FIG. 7 (b) is shown in FIG. 7 (a). It is sectional drawing of the VII-VII line shown. The light emitting device 141 according to the fourth embodiment of the present invention is a device in which the combination of the upper electrode layer 43 and the organic light emitting layer 42 is specified in the light emitting device 111 according to the first embodiment. In addition, the same member as 1st Embodiment has attached | subjected the same code | symbol, and abbreviate | omits description.

The upper electrode layer 43 uses phthalocyanine-based copper phthalocyanine green, which is an organic pigment, as the pigment 14, and its electrode color is light green. In the upper electrode layer 43, the pigment 14 and the conductive member 16 are dispersed in the matrix of the binder resin 15, and the upper electrode layer 43 is formed in the light emitting region LA in the portion surrounded by the bank (sealing wall) 202. Is formed.

In addition, the organic light emitting layer 42 is made of polyvinyl carbazole (PVK), which is a high molecular material hole transport material, and low molecular 2,5-bis (1-naphthyl) -1,3,4-oxadiazole (BND). ) (Which is an electron transporting material), 3- (2′-benzothiazolyl) -7-diethylaminocoumarin (coumarin-6) (which is a luminescent material) is added and used, and its emission color is green. is there.

When the light emission in the light emitting region LA of the organic light emitting layer 42 sandwiched between the upper electrode layer 43 and the light transmissive lower electrode layer 11 is viewed from the light transmissive substrate 19 side of the light emitting device 141, the light emission of the organic light emitting layer 42 is observed. The color is visually recognized by overlapping the light green electrode color of the upper electrode layer 43 with the green light emission color of the organic light emitting layer 42.

As described above, in the light emitting device 141 according to the fourth embodiment of the present invention, since the pigment 14 included in the upper electrode layer 43 is a similar color that reflects the emission color of the organic light emitting layer 42, the upper portion including the pigment 14 is included. The electrode layer 43 has a similar color shade. For this reason, the light from the light emitting region LA is visually recognized because the color of the upper electrode layer 43 overlaps with the color of the organic light emitting layer 42, so that the organic light emitting layer depends on the electrode color of the upper electrode layer 43. Thus, the original color of the 42 emission colors is visually recognized. By this, the quality of the luminescent color of the organic light emitting layer 42 can be improved.

Further, the present invention can also be applied to the lower electrode layer 27 and the organic light emitting layer 22 of the light emitting device 121 according to the second embodiment of the present invention. According to this, since the pigment contained in the lower electrode layer is a similar color that reflects the emission color of the organic light emitting layer, the lower electrode layer containing the pigment has a hue of the similar color. For this reason, the light from the light emitting region LA is visually recognized because the electrode color of the lower electrode layer and the light emission color of the organic light emitting layer overlap each other, so the light emission color of the organic light emitting layer depends on the electrode color of the lower electrode layer. It will be visible without compromising the original color of the. By this, the quality of the luminescent color of an organic light emitting layer can be improved.

[Fifth Embodiment]
FIG. 8 is a plan view for explaining a light emitting device 151 according to the fifth embodiment of the present invention. Moreover, in FIG. 8, the sealing layer actually provided is abbreviate | omitted and described. As shown in FIG. 8, the light emitting device 151 according to the fifth embodiment of the present invention is provided with a lower electrode layer 57 on a substrate (not shown) and an organic light emitting layer 52 between the light transmissive upper electrode layer 58. Is arranged. Then, by supplying current to the upper and lower electrode layers via the lead electrode 257 and the lead electrode 258, the light from the light emitting region LA sandwiched between the lower electrode layer 57 and the light transmissive upper electrode layer 58 can be It is visually recognized as emitted light of the light emitting device 151 through the light transmissive upper electrode layer 58 toward the surface side (top emission type). In order to improve the environmental resistance, a sealing layer (not shown) is provided on part of the organic light emitting layer 52, the lower electrode layer 57, the light transmissive upper electrode layer 58, and the lead electrode 258 so that the light emitting region LA is formed. It is sealed.

The lower electrode layer 57 has the same configuration and material as the lower electrode layer 27 of the light emitting device 121 according to the second embodiment of the present invention. Similarly, the organic light emitting layer 52, the light transmissive upper electrode layer 58, the lead electrode 257, and the lead electrode 258 have the same configuration and materials as those of the light emitting device 121 according to the second embodiment of the present invention.

As described above, in the light emitting device 151 according to the fifth embodiment of the present invention, since the lower electrode layer 57 contains the pigment, the pigment in the lower electrode layer 57 is changed to the light transmissive upper electrode layer 58 and the organic light emitting layer 52. The external light applied to the lower electrode layer 57 through the light is absorbed or scattered, so that the reflectance of the external light applied to the lower electrode layer 57 is reduced and the light emitting region LA of the organic light emitting layer 52 when not emitting light is reduced. The intensity of the reflected light can be reduced. As a result, the contrast between the light emitting area LA and the non-light emitting area of the organic light emitting layer 52 is increased and visibility can be improved without causing a significant decrease in luminance as in the prior art. Further, the contrast between the light emitting area LA and the non-light emitting area NL of the organic light emitting layer 52 is reduced, and the pattern can be camouflaged.

Further, since the lower electrode layer 57 contains a binder resin and a conductive member, a composite film that is not a metal film is used for the lower electrode layer 57, so that external light applied to the lower electrode layer 57 is used. And the reflectance can be lowered, and the difference in light intensity between when the light emitting region LA of the organic light emitting layer 52 emits light and when it does not emit light can be increased. The intensity of the reflected light of the light emitting area LA of the organic light emitting layer 52 when not emitting light can be reduced. As a result, the contrast between the light emitting area LA and the non-light emitting area of the organic light emitting layer 52 is increased without significantly reducing the brightness as in the prior art, and the visibility can be greatly improved. Furthermore, the contrast between the light emitting area LA and the non-light emitting area NL of the organic light emitting layer 52 is reduced, and the pattern is camouflaged.

The embodiment shown in FIG. 8 is a 7-segment display having seven light emitting areas LA, but is widely applied to other products such as other segment displays and dot matrix displays. Further, the substrate can be used as a bottom emission type by using a light-transmitting substrate, the lower electrode layer 57 as a light-transmitting lower electrode layer, and the light-transmitting upper electrode layer 58 as an upper electrode layer.

[Sixth Embodiment]
FIG. 9 is a perspective view illustrating the configuration of a light emitting device panel 361 using the light emitting device 161 according to the sixth embodiment of the present invention. The light emitting device 161 according to the sixth embodiment of the present invention is a light emitting device 121 according to the second embodiment, in which the organic light emitting layer 62 and the substrate 69 are particularly limited. In addition, the same member as 2nd Embodiment attaches | subjects the same code | symbol, and abbreviate | omits description.

As the substrate 69 of the light emitting device 161 according to the sixth embodiment of the present invention, a substrate having optical transparency is used among rigid substrates such as a glass substrate and a synthetic resin substrate, and film substrates such as a plastic film. In particular, since it has flexibility, a plastic film is preferably used. As a resin material for a plastic film or a synthetic resin substrate having optical transparency, resins such as PET (polyethylene terephthalate), PEN (polyethylene naphthalate), PP (polypropylene), PS (polystyrene), and acrylic (PMMA) are used. . Among these, PET or PEN is particularly preferably used in terms of light transmittance, flexibility, and heat resistance.

In addition, the organic light emitting layer 62 of the light emitting device 161 uses a light transmissive layer. For example, polyvinylcarbazole (PVK) is added to low molecular weight 2,5-bis (1-naphthyl) -1,3,4-oxadiazole (BND), 3- (2′-benzothiazolyl) -7-diethylaminocoumarin ( The organic light emitting layer 62 used by adding coumarin-6) is a green transparent layer.

Since the organic light emitting layer 62 is a colored transparent layer, for example, when carbon black is used as the pigment 24 of the lower electrode layer 27, the electrode color of the lower electrode layer 27 is blackish gray, and the lower electrode is made of copper phthalocyanine green. The electrode color of the layer 27 is green light green. Further, since the substrate 69 has light transmittance and the organic light emitting layer 62 is a colored transparent layer, the non-light emitting region NL without the lower electrode layer 27 has light transmittance.

The light emitting device panel 361 using the light emitting device 161 of the sixth embodiment of the present invention has a structure in which a synthetic resin panel 300 is attached to the back side of the light emitting device 161 that is not the viewing side. The panel 300 is characterized by similarly reflecting light in a wavelength region including a specific peak wavelength reflected by the pigment 24, that is, a color similar to that of the pigment 24. Further, the panel 300 has a plate shape as shown in FIG. 9, but may be a box-like case, a curved panel, or the like, and is not limited to the plate shape. Further, the panel 300 only needs to have a color similar to that of the pigment 24, and the panel 300 can be replaced by providing a similar color layer on the exterior parts of other products of the same color or the back surface of the substrate 69. You can also.

From the light transmissive upper electrode layer 28 side of the light emitting device 161, the light emitting area LA of the organic light emitting layer 62 sandwiched between the light transmissive upper electrode layer 28 and the lower electrode layer 27 and the non-light emitting area NL without the lower electrode layer 27. Since the color of the panel 300 is visually recognized in the non-light emitting area NL having light transmittance, the electrode color of the lower electrode layer 27 containing the pigment 24 and the non-light emitting area NL are similar. Visible as a color. That is, when the organic light emitting layer 62 is not emitting light, the light emitting area LA and the non-light emitting area NL of the organic light emitting layer 62 are visually recognized as similar colors.

As described above, in the light emitting device panel 361 using the light emitting device 161 according to the sixth embodiment of the present invention, the substrate 69 of the light emitting device 161 is light transmissive, and the organic light emitting layer 62 is a colored transparent layer. At the same time, since the panel 300 of the light emitting device 161 reflects light in the wavelength region including the same specific peak wavelength as the pigment 24, the electrode color of the lower electrode layer 27 containing the pigment 24 and the color of the panel 300 are different. The visually recognized non-light emitting area NL is visually recognized as a similar color. As a result, when the organic light emitting layer 62 is not emitting light, the chromaticity difference between the light emitting area LA and the non-light emitting area NL of the organic light emitting layer 62 is reduced, and the camouflage of the pattern is further achieved.

Further, when carbon such as carbon black is used as the pigment 24 of the lower electrode layer 27, the electrode color of the lower electrode layer 27 is blackish gray, and the panel 300 is also blackish color. When the light is not emitted, the pattern is further camouflaged, and the light applied from the outside of the lower electrode layer 27 is absorbed, so that the reflectance of the lower electrode layer 27 can be reduced. As a result, the intensity of the reflected light of the light emitting area LA of the organic light emitting layer 62 when not emitting light can be reduced, so that the contrast between the light emitting area LA and the light emitting area of the organic light emitting layer 62 is increased, and visibility is improved. This can be greatly improved.

Moreover, it is applicable also to the bottom emission type of the light-emitting device 111 of 1st Embodiment of this invention. Further, the sealing layer provided on the upper electrode layer 13 and the organic light emitting layer 12 is formed into a layer that similarly reflects light in a wavelength region including a specific peak wavelength reflected by the pigment 14. It can also be replaced.

The present invention is not limited to the above-described embodiment, and can be modified as appropriate without departing from the scope of the object of the present invention.

11 Light transmissive lower electrode layer 12, 22, 42, 52, 62 Organic light emitting layer 13, 33, 43 Upper electrode layer 14, 24 Pigment 15, 25 Binder resin 16, 26 Conductive member 27, 57 Lower electrode layer 28, 58 Light-transmissive upper electrode layer 19 Light-transmissive substrate 29, 69 Substrate 111, 121, 131, 141, 151, 161 Light-emitting device NPG Nanoparticle-shaped silver

Claims (9)

A light-transmitting lower electrode layer that transmits visible light provided on a light-transmitting substrate that transmits visible light that has a wavelength in the visible region; and
An organic light emitting layer provided on the light transmissive lower electrode layer;
An upper electrode layer provided on the organic light emitting layer,
The light emitting device, wherein the upper electrode layer contains a pigment.   2. The light emitting device according to claim 1, wherein the upper electrode layer contains a binder resin and a conductive member. A lower electrode layer provided on the substrate;
An organic light emitting layer provided on the lower electrode layer;
A transparent upper electrode layer that transmits visible light, which is light having a wavelength in the visible region, provided on the organic light emitting layer;
The light emitting device, wherein the lower electrode layer contains a pigment.   The light emitting device according to claim 3, wherein the lower electrode layer contains a binder resin and a conductive member. The light emitting device according to claim 1, wherein the pigment material includes carbon. The light emitting device according to claim 2, wherein the conductive member contains nanoparticulate silver. The light emitting device according to claim 5, wherein a ratio of the carbon contained in the upper electrode layer and the lower electrode layer is 5 wt% or more and 10 wt% or less. 5. The light emitting device according to claim 1, wherein the pigment reflects light in a wavelength region including a peak wavelength of light emission from the organic light emitting layer. 4. The light emitting device according to claim 3, wherein the light transmissive upper electrode layer is a transparent conductive polymer.