JP2007103028A - Organic electroluminescent display device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an organic electroluminescent display device capable of restraining rise of drive voltage through restraint of degradation of an organic EL element part due to ultraviolet rays and maintaining excellent color display quality. <P>SOLUTION: The device is provided with an organic EL element part for emission of white light equipped with a red-color emission area, a green-color emission area, a blue-color emission area and a white-color emission area, a translucent substrate 1 at a light emission side against the organic EL element part, and color conversion layers CFR, CFG, CFB for converting the white light from the organic EL element part to a color corresponding to each emission area in the red-color emission area, the green-color emission area, and the blue-color emission area. An ultraviolet absorption layer 30 with a light absorption ratio of 10% or more at a wavelength of 380 nm is provided between the translucent substrate 1 and the organic EL element, in the white-color emission area. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to an organic electroluminescence display device (organic EL display device).

  In recent years, with the diversification of information equipment, development of a display using an organic electroluminescence element (organic EL element) is expected as a flat display element that consumes less power than a CRT that has been generally used. .

  Further, the organic EL element is also expected as a pollution-free (mercury-less) lighting device that replaces a fluorescent lamp or the like.

  In the organic EL element, electrons and holes are injected into the light emitting layer from the electron injection electrode and the hole injection electrode, respectively, so that the electrons and holes are recombined in the light emitting layer to bring the organic molecules into an excited state. The excited organic molecules emit light by fluorescence emitted when returning to the ground state. In this organic EL element, it is known that the luminous efficiency can be increased by laminating an electron transporting material, a hole transporting material, and a light emitting material as a multilayer structure.

  In recent years, an organic EL element including a plurality of light emitting layers having different emission wavelengths has been proposed (see, for example, Patent Document 1). This Patent Document 1 discloses an organic EL element including a first light emitting layer that emits orange light and a second light emitting layer that emits blue light. By this blue light emission and orange light emission, white light emission can be obtained.

  In order to apply these organic EL elements to a display, there is a method in which elements that emit three primary colors (RGB) of light are formed at corresponding positions in a pixel, but the manufacturing process is complicated. is there. On the other hand, there has been proposed a method for realizing a full color display by avoiding a complicated manufacturing process by using an element that emits white light in combination with a color filter layer that transmits RGB monochromatic light (for example, (See Patent Document 2).

In recent years, when white is displayed on a display by adding a white (W) light emitting region to the three primary colors of red (R), green (G), and blue (B) in a pixel, There has been proposed an organic EL display device that emits light in the W region instead of emitting light in the region to reduce power consumption (see, for example, Patent Document 3). In other words, when using an element that emits white light and converting it to monochromatic light with a color filter, the light that passes through the color filter is lost, but since the color filter is not used in the white light-emitting region, power consumption is greatly reduced. can do.
JP 2000-243563 A Japanese Patent Laid-Open No. 10-12383 JP 2004-334204 A

  The organic EL display device using the white light emitting region uses a color filter in the RGB light emitting region, but does not use a color filter in the W light emitting region. Since the color filter hardly transmits ultraviolet rays, ultraviolet rays from outside light such as sunlight are not directly incident on the organic EL element and adversely affected in the RGB emission region. However, in the light emitting region of W where no color filter is used, ultraviolet rays are directly incident, the organic EL element is deteriorated, the drive voltage is increased, and the element life is reduced. For this reason, the problem that the power consumption of the whole display apparatus increases or a lifetime falls will arise.

  In addition, as described above, in an organic EL element in which two light emitting layers such as an orange light emitting layer and a blue light emitting layer are laminated to form a white light emitting layer, the light emission balance is lost due to deterioration of the organic EL element, and white light emission is caused. Cause problems such as not being able to get.

  An object of the present invention is to provide an organic EL display device capable of suppressing deterioration of an organic EL element due to ultraviolet rays, suppressing an increase in driving voltage, and maintaining good color display quality.

  The organic EL display device of the present invention is provided with a red light emitting region, a green light emitting region, a blue light emitting region, and a white light emitting region, and is provided on the light emitting extraction side with respect to the white light emitting organic EL element portion and the organic EL element portion. In order to convert the white light emission from the organic EL element part into a color corresponding to each light emitting area in the red light emitting region, the green light emitting region, and the blue light emitting region, the organic EL element unit emits light. And a color conversion layer provided on the take-out side. In the white light emitting region, an ultraviolet absorption layer having a light absorption rate of 10% or more at a wavelength of 380 nm is provided between the translucent substrate and the organic EL element portion. It is characterized by being provided.

  In accordance with the present invention, in the white light emitting region, an ultraviolet ray absorbing layer having a light absorption rate of 10% or more at a wavelength of 380 nm is provided between the translucent substrate and the organic EL element part, so that the ultraviolet light incident from the white light emitting region is obtained. And the deterioration of the organic EL element due to ultraviolet rays can be suppressed. By setting the light absorption rate at a wavelength of 380 nm in the ultraviolet absorption layer to 10% or more, an effect of suppressing an increase in driving voltage due to deterioration can be rapidly obtained.

  Further, in the red light emitting region, the green light emitting region, and the blue light emitting region, a color conversion layer is provided between the translucent substrate and the organic EL element portion, and a planarizing film is provided on the color conversion layer. The planarizing film can be used as an ultraviolet absorbing layer in the white light emitting region. By using the planarizing film as the ultraviolet absorbing layer, it is not necessary to separately provide a process for forming the ultraviolet absorbing layer, and the manufacturing process can be simplified.

  Further, when the organic EL device of the present invention has a white light emitting layer having a laminated structure of an orange light emitting layer and a blue light emitting layer, the light emission balance between the orange light emitting layer and the blue light emitting layer is lost due to deterioration due to ultraviolet rays, and light emission. However, according to the present invention, since such deterioration of the organic EL element can be suppressed, a good color display quality can be maintained.

  ADVANTAGE OF THE INVENTION According to this invention, deterioration of the organic EL element part by an ultraviolet-ray can be suppressed, the raise of a drive voltage can be suppressed, and a favorable color display quality can be maintained.

  Hereinafter, the present invention will be described with reference to specific embodiments, but the present invention is not limited to the following embodiments.

(First embodiment)
FIG. 1 is a cross-sectional view showing an example of the organic EL display device of the first embodiment according to the present invention.

  As shown in FIG. 1, the display area WL of the organic EL display device includes a red light emitting area (area R), a green light emitting area (area G), a blue light emitting area (area B), and a white light emitting area (area W). The region R has a red color filter layer CFR as a color conversion layer, the region G has a green color filter layer (CFG) as a color conversion layer, and the region B has a blue color filter layer as a color conversion layer. (CFB) is provided, and no color conversion layer is provided in the region W. Therefore, in the region W, the light emitted from the organic EL element part is emitted as it is without passing through the color filter layer as the color conversion layer.

  Hereinafter, the detailed structure of the organic EL display device shown in FIG. 1 will be described.

As shown in FIG. 1, a laminated film 11 of a layer made of, for example, silicon oxide (SiO ₂ ) and a layer made of silicon nitride (SiN _x ) is formed on a transparent substrate 1 made of glass or plastic. Yes. A plurality of TFTs (thin film transistors) 20 are formed on the laminated film 11 so as to correspond to the regions R, G, B, and W, respectively. Each TFT 20 includes a drain electrode 13 d, a source electrode 13 s, a gate oxide film 14, and a gate electrode 15 in the channel region 12. The channel region 12 is formed from, for example, a polysilicon layer, and a drain electrode 13 d and a source electrode 13 s are formed on the channel region 12. A gate electrode 15 is formed on the channel region 12 via a gate oxide film 14.

  The drain electrode 13d of each TFT 20 is connected to a hole injection electrode 2 provided for each region R, G, B, and W. The source electrode 13s is connected to a power supply line (not shown). The TFT 20 drives the pixels in each region.

  A first interlayer insulating film 16 is formed on gate oxide film 14 so as to cover gate electrode 15. A second interlayer insulating film 17 is formed on the first interlayer insulating film 16 so as to cover the drain electrode 13d and the source electrode 13s. The gate electrode 15 is connected to a signal line (not shown). The gate oxide film 14 has a laminated structure of a layer made of, for example, silicon nitride and a layer made of silicon oxide. The first interlayer insulating film 16 has a stacked structure of, for example, a layer made of silicon oxide and a layer made of silicon nitride, and the second interlayer insulating film 17 is made of, for example, silicon nitride.

  On the second interlayer insulating film 17, a red color filter layer CFR, a green color filter layer CFG, and a blue color filter layer CFB are formed corresponding to the regions R, G, and B, respectively. The red color filter layer CFR transmits light in the red wavelength region. The green color filter layer CFG transmits light in the green wavelength region. The blue color filter layer CFB transmits light in the blue wavelength region.

  Each of the color filter layers described above can be formed from a material such as glass or plastic. Further, as each color filter layer, a CCM (color conversion medium) that converts the wavelength of incident light and emits it may be used. Further, the color conversion layer may be formed using both a material such as glass or plastic and CCM.

  A planarizing film 18 is formed on the second interlayer insulating film 17 so as to cover the color filter layers. In the region W where the color filter layer is not provided, the ultraviolet absorbing layer 30 is formed from the same material as the planarizing film 18. The planarization film 18 and the ultraviolet absorption layer 30 can be formed from the same material, and can be formed in the same manufacturing process. The planarizing film 18 and the ultraviolet absorbing layer 30 can be formed as follows.

  For example, an acrylic photosensitive resin is applied by spin coating, and then pre-baked (for example, at 80 ° C. for 10 minutes) in a thermostatic bath or a hot plate. Thereafter, the photosensitive resin on the drain electrode 13d is exposed and developed to form a contact hole, and further post-baked (for example, at 190 ° C. for 15 minutes) to completely harden the resin.

  In the embodiment shown in FIG. 1, the ultraviolet absorbing layer 30 is thicker than the planarizing film 18. In such a case, after the ultraviolet absorbing layer 30 having the same thickness as that of the planarizing film 18 is formed in the same manner as described above, a photosensitive resin is applied only to the region W and pre-baked. After that, the photosensitive resin on the drain electrode 13d is exposed and developed in the same manner as described above to form a contact hole, and then post-baking is performed.

  After forming a transparent conductive film made of indium-tin oxide (ITO) or the like on the planarizing film 18 and the ultraviolet absorbing layer 30 by sputtering or the like and forming a resist pattern on the transparent conductive film by a photolithography process The hole injection electrode 2 is formed by etching. The hole injection electrode 2 and the drain electrode 13d are electrically connected by a contact hole.

  An organic EL element portion is formed on the hole injection electrode 2. The organic EL element part is formed on a hole injection electrode 2, a hole injection layer 3, a hole transport layer 4, an orange light emitting layer 5 a that emits orange light, a blue light emitting layer 5 b that emits blue light, an electron transport layer 6, an electron injection The layer 7 and the electron injection electrode 8 are formed by laminating in this order.

  The hole injection electrode 2 is formed for each of the regions R, G, B, and W, and an insulating pixel isolation film 19 is formed between these regions so as to cover the hole injection electrode 2. . The hole injection electrode 2 is formed of a transparent conductive film such as ITO having a thickness of 100 nm, for example.

  A hole injection layer 3 is formed on the entire region so as to cover the hole injection electrode 2 and the pixel isolation film 19. The hole injection layer 3 is made of, for example, fluorocarbon (CFx) having a thickness of 1 nm.

  A hole transport layer 4 is formed on the hole injection layer 3. The hole transport layer 4 is formed of, for example, NPB (N, N′-di (naphthalen-1-yl) -N, N′-diphenylbenzidine) having a structure of the following (Chemical Formula 1) having a thickness of 60 nm. Yes.

  In general, a triarylamine derivative, a benzidine derivative, or the like can be used as the hole transporting material for forming the hole transport layer.

  On the hole transport layer 4, an orange light emitting layer 5a is formed. The orange light emitting layer 5a has a configuration in which a host material is doped with a first dopant and a second dopant. The orange light emitting layer 5a has a thickness of 30 nm, for example. As the host material of the orange light emitting layer 5a, for example, the same NPB as the material of the hole transport layer 4 can be used.

  As the first dopant of the orange light emitting layer 5a, for example, tBuDPN (5,12-bis (4-tertiarybutylphenyl) naphthacene) represented by (Chemical Formula 2) can be used. The first dopant is doped so as to be 20% by weight with respect to the orange light emitting layer 5a.

  As the second dopant of the orange light emitting layer 5a, for example, DBzR (5,12-bis (4- (6-methylbenzothiazol-2-yl) phenyl) -6,11- Diphenylnaphthacene) can be used. This second dopant is doped so as to be 3% by weight with respect to the orange light emitting layer 5a.

  In the orange light emitting layer 5a, the second dopant emits light, and the first dopant has both the highest occupied molecular orbital (HOMO) level and the lowest unoccupied molecular orbital (LUMO) level, and the host material and the second dopant. Therefore, it plays a role of assisting light emission of the second dopant by promoting energy transfer from the host material to the second dopant. Thereby, the orange light emitting layer 5a emits orange having a peak wavelength larger than 500 nm and smaller than 650 nm.

  Next, the blue light emitting layer 5b is formed on the orange light emitting layer 5a. The blue light emitting layer 5b has a configuration in which a host material is doped with a first dopant and a second dopant. The blue light emitting layer 5b has a thickness of 40 nm, for example.

  As a host material of the blue light emitting layer 5b, for example, TBADN (2-tertiarybutyl-9,10-di (2-naphthyl) anthracene) shown in (Chemical Formula 4) can be used.

  As the first dopant of the blue light emitting layer 5b, for example, the same NPB as the material of the hole transport layer 4 can be used. This first dopant is doped so as to be 10% by weight with respect to the blue light emitting layer 5b.

  As the second dopant of the blue light emitting layer 5b, for example, TBP (1,4,7,10-tetra-tert-butylphenylene) represented by (Chemical Formula 5) can be used. The second dopant is doped so as to be 2.5% by weight with respect to the blue light emitting layer 5b.

  In the blue light emitting layer 5b, the second dopant emits light, and the first dopant is made of a hole transporting material, promotes hole transport, and promotes carrier recombination in the blue light emitting layer 5b. It plays a role of assisting the light emission of the second dopant. Thereby, the blue light emitting layer 5b emits blue light having a peak wavelength larger than 400 nm and smaller than 500 nm.

  Next, the electron transport layer 6, the electron injection layer 7, and the electron injection electrode 8 are formed on the blue light emitting layer 5b.

  The electron transport layer 6 is made of, for example, Alq3 (tris (8-hydroxyquinolinato) aluminum) represented by (Chemical Formula 6) having a thickness of 10 nm.

  The electron injection layer 7 is made of, for example, lithium fluoride (LiF) having a thickness of 1 nm, and the electron injection electrode 8 is made of, for example, aluminum (Al) having a thickness of 200 nm.

  FIG. 2 is a plan view showing an example of an arrangement state of the regions R, G, B, and W. FIG.

  In the organic EL display device shown in FIG. 1, the regions R, G, B, and W are arranged in a line as shown in FIG. The area of each region is different in order to compensate for the difference in emission intensity in each region.

  The arrangement of each area may be an arrangement in which, for example, a quadrangle as shown in FIG. 3 is divided into four quadrangles.

  FIG. 4 is a diagram illustrating absorption spectra of the red color filter layer CFR, the green color filter layer CFG, and the blue color filter layer CFB. In FIG. 4, the vertical axis represents the light transmittance of each color filter layer, and the horizontal axis represents the wavelength of light transmitted through each color filter layer. In FIG. 4, the absorption spectrum of the red color filter layer CFR is indicated by ◯, the absorption spectrum of the green color filter layer CFG is indicated by Δ, and the absorption spectrum of the blue color filter layer CFB is indicated by □.

  As shown in FIG. 4, in the ultraviolet region (400 nm or less), the transmittance of all color filter layers is 40% or less (absorption rate of 60% or more), and at a wavelength of 380 nm, the transmittance is It is 10% or less (absorption rate is 90% or more), and almost no ultraviolet rays are transmitted. For this reason, in the regions R, G, and B where the color filter layer is disposed, there is almost no adverse effect such as deterioration due to ultraviolet rays.

  In the present embodiment, the ultraviolet absorbing layer 30 is formed in the region W. The ultraviolet absorbing layer 30 is made of an acrylic photosensitive resin and has a thickness of 2.0 μm.

  Here, in order to examine the relationship between the ultraviolet absorptance in the ultraviolet absorbing layer and the light degradation, the organic EL device shown in FIG. 5 was produced.

As shown in FIG. 5, an ultraviolet absorbing layer 30 made of an acrylic photosensitive resin is applied on a glass substrate 1 by spin coating so as to have various film thicknesses, and is applied on a hot plate. It was cured by baking at 190 ° C. for 15 minutes. On top of this, a hole injection electrode 2 (anode) made of ITO is formed with a film thickness of 100 nm, and the glass substrate 1 on which the hole injection electrode 2 is formed is washed with a neutral detergent and immersed in acetone to obtain 10 Ultrasonic cleaning was performed for 1 minute, followed by immersion in ethanol and ultrasonic cleaning for 10 minutes, and then the surface of the glass substrate 1 was cleaned with an ozone cleaner. Next, a hole injection layer 3 made of CFx was formed on the hole injection electrode (anode) 2 by a plasma CVD method using CHF ₃ gas.

  A hole transport layer 4 made of NPB having a thickness of 60 nm was formed on the hole injection layer 3 by a vacuum deposition method. On the hole transport layer 4, an orange light emitting layer 5a having a thickness of 30 nm was formed by a vacuum deposition method. The orange light emitting layer 5a contains NPB as a host material, and contains 20% by weight of tBuDPN and 3% by weight of DBzR as dopants.

  A blue light-emitting layer 5b having a thickness of 40 nm was formed on the orange light-emitting layer 5a by a vacuum deposition method. The blue light emitting layer 5b contains TBADN as a host material, and contains 10% by weight of NPB and 2.5% by weight of TBP as dopants.

  An electron transport layer 6 made of Alq3 is formed with a thickness of 10 nm on the blue light emitting layer 5b, an electron injection layer 7 made of LiF is formed thereon with a thickness of 1 nm, and an electron injection electrode 8 made of Al is made 200 nm. The thickness was formed.

All of the vacuum deposition methods were performed in an atmosphere having a degree of vacuum of 1 × 10 ⁻⁶ Torr without controlling the substrate temperature.

  The ultraviolet absorbing layer 30 was formed with thicknesses of 0.5 μm, 1.0 μm, 1.5 μm, 2.0 μm, 2.5 μm, 3.0 μm, and 3.5 μm, respectively.

For each organic EL element formed by changing the thickness of the ultraviolet absorbing layer as described above, the voltage increase after light irradiation was measured. The initial drive voltage was 6.5 V for any organic EL element. The drive voltage was adjusted so that the current density was 20 mA / cm ^2, and the initial drive voltage and the drive voltage after light irradiation were measured. As light irradiation conditions, 100 mW / cm ² of light in an air mass (hereinafter referred to as AM) 1.5 was irradiated for 30 hours.

  For each organic EL element, a voltage increase value after light irradiation is obtained, and the relationship between the light absorption rate at a wavelength of 380 nm caused by the difference in film thickness of the ultraviolet absorption layer and the voltage increase after light irradiation is shown in Table 1 and FIG. It was.

  As shown in Table 1 and FIG. 6, when the light absorptance at a wavelength of 380 nm is 10% or more, the voltage increase value after light irradiation decreases rapidly. Therefore, by setting the light absorption rate at a wavelength of 380 nm in the ultraviolet absorbing layer to 10% or more, an increase in driving voltage due to deterioration can be suppressed, and power consumption can be reduced and the life can be extended.

  In addition, an organic EL element having an ultraviolet absorption layer thickness of 1.0 μm (light absorption rate 5.3% at a wavelength of 380 nm) and an ultraviolet absorption layer thickness of 2.0 μm (light absorption rate 13 at a wavelength of 380 nm). .5%) organic EL elements were measured for changes in chromaticity after light irradiation.

  The chromaticity of the organic EL element before light irradiation was CIEx = 0.31 and CIEy = 0.33. Here, CIEEx and CIEy are the x coordinate and y coordinate in the CIE color system in which the color space is expressed in the XY coordinate system, respectively. After light irradiation, when the film thickness of the ultraviolet absorbing layer was 2.0 μm, there was almost no change as CIEx = 0.31 and CIEy = 0.34, but when the film thickness of the ultraviolet absorbing layer was 1.0 μm Changed to a color closer to orange with CIEx = 0.33 and CIEy = 0.40. This is considered to be because when the film thickness of the ultraviolet light absorbing layer becomes 1.0 μm, the deterioration of the blue light emitting material due to the ultraviolet light greatly proceeds as compared with the orange light emitting material, and the blue light emission intensity relatively decreases. .

(Second Embodiment)
FIG. 7 is a cross-sectional view showing an example of the organic EL display device of the second embodiment according to the present invention. The organic EL display device shown in FIG. 7 is a so-called top emission type organic EL display device that extracts light emitted from the organic EL element portion from the side opposite to the substrate side provided with the drive circuit.

  In the organic EL display device shown in FIG. 7, similarly to the organic EL display device shown in FIG. 1, on the substrate 1, a laminated film 11, a TFT 20, a first interlayer insulating film 16, a second interlayer insulating film 17, A planarization film 18 and a pixel isolation film 19 are formed, and an organic EL element portion is formed thereon.

  A sealing substrate 21 is bonded above the organic EL element portion through a transparent adhesive layer 23. On the bonding surface of the sealing substrate 21, a red color filter layer CFR, a green color filter layer CFG, and a blue color filter layer CFB are formed corresponding to the regions R, G, and B. A protective film 22 is formed on the surface of the sealing substrate 21 on the adhesive side so as to cover these color filter layers, CFR, CFG, and CFG. The protective film 22 can be formed of, for example, an acrylic photocurable resin.

  In the region W, the ultraviolet absorbing layer 30 is formed by forming the protective film 22 thick. In this embodiment, the ultraviolet absorbing layer 30 is formed to have a thickness of 1.5 μm.

In this embodiment, the sealing substrate 21 can be formed from, for example, a layer made of glass, silicon oxide (SiO ₂ ), or a layer made of silicon nitride (SiNx).

  In the organic EL display device of this embodiment, the substrate 1 may be formed of an opaque material. The hole injection electrode 2 is formed, for example, by laminating ITO having a thickness of about 50 nm and aluminum, chromium, silver, or an alloy thereof having a thickness of 100 nm. In this case, the hole injection electrode 2 reflects the light emitted from the organic EL element to the sealing substrate 21 side.

  The electron injection electrode 7 is made of a transparent material. The electron injection electrode 7 can be formed, for example, by laminating ITO having a thickness of 100 nm and silver having a thickness of 20 nm.

  Other configurations of the organic EL display device shown in FIG. 7 are substantially the same as those of the organic EL display device shown in FIG.

  In the organic EL display device shown in FIG. 7, the white light emitted from the organic EL element portion is transparent adhesive layer 23, protective film 22, each color filter layer, and transparent sealing in regions R, G, and B. The light passes through the stop substrate 21 and is extracted to the outside as red light, green light, and blue light, respectively. On the other hand, in the region W, there is no color filter layer, and the colored light from the organic EL element portion passes directly through the transparent adhesive layer 23, the ultraviolet absorbing layer 30, and the transparent sealing substrate 21. The white light is extracted outside.

  In the organic EL display device according to the present embodiment, the ultraviolet absorbing layer 30 having a thickness of 1.5 μm is provided in the region W where the color filter layer is not provided. The ultraviolet absorption layer 30 has a light absorption rate of 10% or more at a wavelength of 380 nm, and can cut ultraviolet rays that enter the organic EL element portion from the outside. For this reason, in the organic EL display device of the present embodiment, it is possible to suppress deterioration of the organic EL element portion due to ultraviolet rays and to suppress an increase in driving voltage. In addition, it is possible to suppress deterioration in the balance of light emission in the organic EL element portion, and it is possible to maintain good color display quality.

  The organic EL display device shown in FIG. 7 has a top emission structure, and an area on the TFT can also be used as a pixel area. For this reason, since a wider area | region can be used as a pixel area | region, the brightness | luminance of an organic electroluminescent display apparatus can be raised further.

Sectional drawing which shows the organic electroluminescence display of 1st Embodiment according to this invention. The top view which shows an example of arrangement | positioning of area | region R, G, B, and W. FIG. The top view which shows the other example of arrangement | positioning of area | region R, G, B, and W. FIG. The figure which shows the transmittance | permeability in each wavelength in a red color filter, a green color filter, and a blue color filter. Sectional drawing which shows the structure of the organic electroluminescence display produced in order to examine the relationship between the light absorptivity in wavelength 380nm, and the voltage rise after light irradiation. The figure which shows the relationship between the light absorption factor in wavelength 380nm, and the voltage rise after light irradiation. Sectional drawing which shows an organic electroluminescence display in 2nd Embodiment according to this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Substrate 2 ... Hole injection electrode 3 ... Hole injection layer 4 ... Hole transport layer 5a ... Orange light emitting layer 5b ... Blue light emitting layer 6 ... Electron transport layer 7 ... Electron injection layer 8 ... Electron injection electrode 11 ... Multilayer film 14 ... Gate oxide film 16 ... first interlayer insulating film 17 ... second interlayer insulating film 18 ... flattening film 19 ... pixel isolation film 20 ... TFT
DESCRIPTION OF SYMBOLS 21 ... Sealing substrate 22 ... Protective film 23 ... Adhesive layer 30 ... Ultraviolet absorption layer CFR ... Red color filter layer CFG ... Green color filter layer CFB ... Blue color filter layer

Claims (3)

A red light emitting area, a green light emitting area, a blue light emitting area, and a white light emitting area are provided,
A white light emitting organic EL element,
A translucent substrate provided on the light emission extraction side with respect to the organic EL element portion;
In the red light emitting region, the green light emitting region, and the blue light emitting region, the light emission side of the organic EL element unit is changed to convert white light emission from the organic EL element unit into a color corresponding to each light emitting region. An organic electroluminescence display device comprising a color conversion layer provided in
In the white light-emitting region, an organic electroluminescent device is characterized in that an ultraviolet absorption layer having a light absorptance of 10% or more at a wavelength of 380 nm is provided between the translucent substrate and the organic EL element portion. Luminescence display device.   In the red light emitting region, the green light emitting region, and the blue light emitting region, the color conversion layer is provided between the translucent substrate and the organic EL element part, and is provided on the color conversion layer. An organic electroluminescence display device, wherein the planarized film constitutes the ultraviolet absorbing layer in the white light emitting region. 3. The organic electroluminescence display device according to claim 1, wherein the organic EL element portion has a white light emitting layer having a laminated structure of an orange light emitting layer and a blue light emitting layer.

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