WO2009098793A1 - Organic el display and manufacturing method thereof - Google Patents

Abstract

An organic EL display has a substrate; a color conversion filter section including a planarized layer and at least one kind of color conversion layer; an organic EL element section having a plurality of luminescent sections, which define a plurality of sub-pixels; and an interface in the uneven form between the substrate and the planarized layer, wherein the uneven form has uneven density different for each of the sub-pixels. In such an arrangement, the top surface of the substrate has a predetermined form for each of the sub-pixels defined by the luminescent sections on the organic EL element section to make a fine adjustment of the directivity of light among different color sub-pixels, thereby preventing variation in the luminescent colors depending on viewing field angles at high levels.

Description

Organic EL display and manufacturing method thereof

The present invention relates to an organic electroluminescence display (hereinafter also referred to as “organic EL display”). More specifically, the organic EL display according to the present invention relates to an organic EL display in which light emitted from the organic EL element portion to the outside does not exhibit a different emission color depending on a viewing angle. The present invention relates to a method for manufacturing such an organic EL display.

Currently, display devices such as liquid crystal displays and organic EL displays are used as display units for electronic devices such as mobile phones, personal computers, digital copiers, and printers.

The light emitting form of the display device includes a self light emitting type and a non-light emitting type. The self-luminous type is applied to an electroluminescence element (EL element), a field emission display (FED), a cathode ray tube (CRT), and the like. On the other hand, the non-light emitting type is applied to a liquid crystal display element or the like.

Also, the color display method of the display device includes a multi-color method or a full-color method that realizes light emission of three primary colors of red, green, and blue. In these systems, a means for interposing a color filter layer between the light exit surface of the light emitting element and the image surface is frequently used. According to this means, it is possible to selectively emit light of a specific wavelength from the light emitting element and improve the color purity of light emission of the three primary colors, thereby improving the image display quality.

Among such display devices, the following technologies have been proposed particularly for organic EL displays.

Patent Document 1 discloses an organic EL element portion having an organic EL material portion and a fluorescent material portion that absorbs light emitted from the organic EL material portion and emits visible light fluorescence. This element is equipped with a color conversion filter containing a fluorescent material in the fluorescent material part, so that the light emitted from the organic EL material part is absorbed by the fluorescent material part to emit fluorescence in the visible light range, thereby realizing a color conversion method. To do.

In the technique disclosed in Patent Document 1, the light emission color of the organic EL element portion is not limited to white. For this reason, an organic EL element part having higher luminance than conventional ones can be applied as a light source. For example, blue light is wavelength-converted into green light or red light by a color conversion method using a blue light emitting organic EL element part. Can do.

In recent years, a weak energy ray in the wavelength range of near-ultraviolet light to visible light of an illuminant is obtained by patterning a fluorescent material portion containing a fluorescent material dye with high definition as disclosed in Patent Document 1. The color conversion type full color display used is attracting attention.

The color conversion layer (corresponding to the fluorescent material part) used in the color conversion method can be formed mainly by a wet process using a photoresist or a dry process using a vapor deposition method. However, since the material used for the color conversion layer has low heat resistance, it is difficult to completely dry the color conversion layer and the photoresist when a wet process is employed. For this reason, according to the wet process, moisture remaining after drying may move from the color conversion layer to the organic EL layer, and a non-luminous defect called a dark area may occur in the organic EL layer. Therefore, the color conversion layer is actively formed not by a wet process but by a dry process. For example, the following techniques have been proposed.

In Patent Document 2, a color filter layer, a fluorescence conversion layer (corresponding to a color conversion layer), a barrier layer, a hole injection electrode, and an electron injection electrode are provided on a substrate, and an organic layer involved in a light emitting function is provided between the electrodes. An organic EL display device having a color filter layer formed by a vapor deposition method is disclosed. In Patent Document 2, not only the color filter layer but also the color conversion layer is formed by a vapor deposition method (dry process). This is because the color conversion layer is weak against moisture and it is desired to suppress the occurrence of the dark area. Here, when the color conversion layer is formed by a dry process and the color filter layer or the flattening layer that is the base of the color conversion layer is formed by a wet process, the color conversion is performed after these are completely dried at a high temperature. It is desirable to form a layer.

In the formation of the color conversion layer by such a dry process, the color conversion layer can be selectively formed on the flattening layer according to the red, green, and blue subpixels. Since the refractive index of the planarization layer and the glass substrate is about 1.5, whereas the refractive index of the color conversion layer is about 2, the sub-pixel formed with the color conversion layer does not form the color conversion layer. Compared with sub-pixels, light directivity is low. For example, when the color conversion layer is formed only on the red sub-pixel, the red sub-pixel has lower light directivity than the green sub-pixel and the blue sub-pixel.

Further, when a plurality of types of color conversion layers are formed, the refractive index between the color conversion layers of the respective colors is different, so that there is a difference in the light directivity between the sub-pixels on which the color conversion layers are formed. For example, when a color conversion layer is formed on a red subpixel and a green subpixel, a difference regarding the directivity of light occurs between these subpixels.

For these reasons, red, green, and blue light emitted from the display may have different directivities, and the emission color of the screen may be different depending on the viewing angle with respect to the display.

In order to increase the amount of light extracted from the sub-pixel, it is important to reduce the refractive index of the planarization layer and / or the glass substrate. However, when the refractive index of the flattening layer or the like is reduced, the difference in refractive index between the flattening layer or the like and the color conversion layer increases. For this reason, the difference in the directivity of light between the subpixel in which the color conversion layer is formed and the subpixel in which the color conversion layer is not formed is further increased, and the emission color of the screen may be further different depending on the viewing angle.

In view of such circumstances, the following techniques have been disclosed as means for preventing a change in the emission color of the screen depending on the viewing angle with respect to the display.

Patent Document 3 includes a pixel having a light emitting functional layer sandwiched between a first electrode and a second electrode on a substrate and a unit pixel group including a plurality of the pixels, and is selected from the unit pixel group. In addition, an organic electroluminescence device is disclosed in which each pixel is provided with a scattering portion that scatters light emitted from the light emitting functional layer.

In the technique disclosed in Patent Document 3, it is said that only a blue subpixel and a green subpixel can be provided with a light diffusing surface by unevenness to prevent a change in emission color due to a viewing angle.

Japanese Patent Laid-Open No. 2003-152897 JP 2001-196175 A JP 2007-73219 A

However, since the unevenness in Patent Document 3 is formed under the same dimensional design in the blue subpixel and the green subpixel, the difference in the directivity of light between subpixels that generate light of different colors is finely adjusted. Therefore, it is impossible to prevent a change in emission color due to the viewing angle at a high level.

Therefore, various countermeasures against changes in emission color depending on the viewing angle have been studied. For example, attempts have been made to change the materials used for the red, green, and blue color conversion layers. However, the change of the material used for the color conversion layer cannot be easily performed because it may adversely affect the color purity and / or luminance of the light emitted from the color conversion layer.

Therefore, it is desired to solve the change in emission color due to the viewing angle without changing the color conversion layer material. As described above, the change in the emission color depending on the viewing angle is caused by the occurrence of different directivities in the red, green, and blue light emitted by the color conversion layer. Specifically, the red directivity is small, while the green and blue directivities are large. Therefore, the above problem can be solved if the difference in directivity of light between red, green, and blue can be reduced.

Therefore, the object of the present invention is to reduce the difference in the directivity of light between the sub-pixels of each color without adversely affecting the color purity and brightness of the light of each color generated from the color conversion layer, and depending on the viewing angle. An object of the present invention is to provide an organic EL display that does not exhibit different emission colors. Moreover, the objective of this invention is providing the manufacturing method of the said organic EL display.

The present invention includes a substrate, a color conversion filter unit including a planarization layer and at least one color conversion layer, and an organic EL element unit having a plurality of light emitting units, and a plurality of subpixels by the plurality of light emitting units. And an interface having a concavo-convex shape between the substrate and the planarizing layer, and the concavo-convex shape relates to an organic EL display having a different concavo-convex density for each sub-pixel. The organic EL display of the present invention can be used as a display unit of an electronic device such as a mobile phone.

The present invention also includes a substrate, a first laminate including a color conversion filter unit including a planarization layer and at least one color conversion layer, a base, and an organic EL element unit having a plurality of light emitting units. A plurality of sub-pixels are defined by the plurality of light emitting portions, an interface having a concavo-convex shape between the substrate and the planarization layer, and the concavo-convex shape is An organic EL display having different uneven density is included for each subpixel.

In such an organic EL display, at least one color filter layer can be interposed between the substrate and the planarizing layer. In this case, the interface between the substrate and the color filter layer has an uneven shape, and the uneven shape has a different uneven density for each sub-pixel.

In these organic EL displays, the concavo-convex shape can be an array shape of a plurality of concave portions and convex portions having at least one period and smaller than the sub-pixel width. Moreover, the said uneven | corrugated shape can be made into the shape which has a different period for every said subpixel.

The present invention provides a step of forming a color conversion filter portion including a planarization layer and at least one color conversion layer on a substrate, and an organic EL element portion having a plurality of light emitting portions on the color conversion filter portion. In manufacturing an organic EL display in which a plurality of sub-pixels are defined by the plurality of light emitting units, a concavo-convex shape is formed on a substrate surface in contact with the planarization layer, and the concavo-convex shape is formed for each sub-pixel. The manufacturing method of the organic electroluminescent display adjusted to different uneven | corrugated density is included.

The present invention also includes a step of forming a color conversion filter portion including a planarization layer and at least one color conversion layer on a substrate to obtain a first laminate, and an organic having a plurality of light emitting portions on a substrate. Including a step of forming an EL element portion to obtain a second stacked body, and a step of bonding the first stacked body and the second stacked body, wherein a plurality of sub-pixels are formed by the plurality of light emitting portions. In manufacturing an organic EL display as defined, an organic EL display manufacturing method is provided in which an uneven shape is formed on a substrate surface in contact with the planarization layer, and the uneven shape is adjusted to a different uneven density for each subpixel. Include.

In such an organic EL display manufacturing method, at least one color filter layer can be formed between the substrate and the planarization layer. In this case, an uneven shape is formed on the substrate surface in contact with the color filter layer, and the uneven shape is adjusted to a different uneven density for each sub-pixel.

In these organic EL displays, the concavo-convex shape can be adjusted to at least one cycle to form an array shape of a plurality of concave portions and convex portions smaller than the sub-pixel width. Moreover, the said uneven | corrugated shape can be adjusted to a different period for every said subpixel.

The organic EL display of the present invention finely adjusts the directivity of light between sub-pixels of different colors by forming the substrate surface into a predetermined shape for each sub-pixel defined by the light emitting unit of the organic EL element unit. In addition, it is possible to prevent a change in emission color due to the viewing angle at a high level.

FIG. 1 is a side sectional view showing an organic EL display of the present invention. FIG. 2 is a side sectional view showing the organic EL display of the present invention. FIG. 3 is a side sectional view showing the organic EL display of Comparative Example 1. FIG. 4 is a side sectional view showing the organic EL display of Comparative Example 2.

Explanation of symbols

DESCRIPTION OF SYMBOLS 100 Substrate 200 Color conversion filter part 210 Color filter layer 210R Red color filter layer 210G Green color filter layer 210B Blue color filter layer 220 Light-shielding layer 230 Flattening layer 240 Red conversion layer 250 Gas barrier layer 300 Organic EL element part 310 Transparent electrode 320 Organic EL layer 330 Reflective electrode 400 Base 500 Adhesive layer X First laminate Y Second laminate

Hereinafter, the principle of the present invention, the organic EL display of the present invention, and the manufacturing method thereof will be described.

<Principle of the present invention>
As a result of intensive studies on the phenomenon in which the emission color changes depending on the angle at which the organic EL display is viewed, the present inventor results from the fact that the directivity of light differs among sub-pixels of different colors (R, G, B). Turned out to be. Therefore, the present inventor has reached a conclusion that such a phenomenon can be avoided by reducing the difference in the directivity of light between these sub-pixels.

Specifically, in the subpixel region defined by the light emitting portion of the organic EL element portion in the interface portion between the substrate and the color filter layer or the flattening layer, uneven portions having different densities are formed for different subpixels. The light of R, G, B emitted from the organic EL element part is allowed to pass through the uneven part. As a result, the directivity of light of each color at the interface is controlled independently by the principle of light scattering, the difference in directivity of light of each color is reduced, and the emission color changes depending on the angle at which the organic EL display is viewed. Can solve the problem.

In addition, about this organic EL display created by the said method, this inventor observed the organic EL display from the front and the diagonal direction, and measured the angular distribution of the emission spectrum. As a result, it has been concluded that the reduction of the directivity difference in the light of each color can be realized while maintaining the performance of the organic EL element part such as chromaticity and luminance.

<Organic EL display and manufacturing method thereof>
[Organic EL display (Type 1)]
Hereinafter, an embodiment of the present invention will be described in detail with reference to FIG. In addition, although the example shown below is an example containing a color filter layer, it is a mere illustration of this invention, Comprising: Those skilled in the art can change a design suitably. That is, an example that does not include a color filter layer can be interpreted in the same manner as the following description.

(About overall configuration)
As shown in FIG. 1, the organic EL display (bottom emission type) of the present invention includes a transparent substrate 100, a color conversion filter unit 200 laminated on one surface of the transparent substrate 100, and light incident on the color conversion filter unit 200. The organic EL element unit 300 having the light-emitting surface facing the surface, and a sealing material (not shown) that blocks the color conversion filter unit 200 and the organic EL element unit 300 from outside air.

The transparent substrate 100 is a layer for supporting each component of the organic EL display sequentially formed thereon. The transparent substrate 100 is rich in light transmission, and the color filter layer 210 (R, G, B), the light shielding layer 220, a red conversion layer 240 described later, and the organic EL element unit 300 (electrode, organic light emitting layer, etc.) ) That can withstand the conditions (solvent, temperature, etc.) used in the formation of). In addition, the transparent substrate 100 is preferably excellent in dimensional stability because it is exposed to repeated formation conditions of each layer in each subsequent forming step. Further, it is important to use a transparent substrate 100 that does not cause a decrease in the light emission performance of the multicolor light emitting display, and examples thereof include glass, various plastics, and various films.

The color conversion filter unit 200 is a color filter including red (R), green (G), and blue (B) color filter layers 210R, 210G, and 210B formed in a stripe shape on one surface of the transparent substrate 100. A layer 210, a light shielding layer 220 that fills the gaps between the color filter layers, a planarization layer 230 formed on the color filter layer 210 and the light shielding layer 220, a red color (R ) A red conversion layer 240 formed at a position corresponding to the color filter layer 210R, and a gas barrier layer 250 formed on the planarization layer 230 so as to wrap the red conversion layer 240.

The organic EL element unit 300 is formed on the gas barrier layer 250 and formed on the gas barrier layer 250 so as to wrap around the transparent electrode 310 formed at a position corresponding to the color filter layer 210. And an organic EL layer 320 and a reflective electrode 330 formed on the organic EL layer 320.

(About uneven shape)
In the example shown in FIG. 1, at least one color filter layer (green color filter layer 210G and blue color filter layer 210B in the example shown in FIG. 1) selected from the color filter layers 210R, 210G, and 210B of each color, The interface with the transparent substrate 100 in contact has an uneven shape.

The uneven shape of the interface (interface 1) between the green color filter layer 210G and the transparent substrate 100 and the uneven shape of the interface (interface 2) between the blue color filter layer 210B and the transparent substrate 100 are reflected at the interface of incident external light. And a shape that can enhance the amount of light outside the incident to the organic EL element unit 300 due to refraction. The uneven shape is a shape that allows the emitted light from the organic EL element unit 300 to be sufficiently scattered and emitted to the image plane.

In the uneven shape of the interfaces 1 and 2, the average depth of the valley is 0.4 to 0.625 μm. Here, the average depth of the valley is the vertical direction of the paper surface of the concave portion adjacent to the position of the vertical direction of the paper surface in each interface shape between each color filter layer 210 (G, B) and the transparent substrate 100 in FIG. The difference from the position means an average value obtained by measuring one representative position in the entire horizontal region of each color filter layer 210 (G, B). The depth is preferably 0.525 to 0.625 μm.

The uneven shape of the interfaces 1 and 2 has an uneven density of 0.83 to 1.99 / μm ² . Here, the uneven density is the number of protrusions per 1 μm ^{2 in the} shape of the interface between the green color filter layer 210G or the blue color filter layer 210B and the transparent substrate 100 (horizontal direction in FIG. 1 × vertical direction in FIG. 1). It means number. The uneven density is preferably 0.83 to 1.18 / μm ² .

Furthermore, the uneven shape of the interfaces 1 and 2 can be a regular or irregular shape having such an average depth of the valley and uneven density. By not excessively increasing the average depth or average density of the valleys, it is possible to suppress excessive irregular reflection of incident external light and to prevent luminance loss of the light emitting surface.

Such a concavo-convex shape has a different concavo-convex density for each sub-pixel (in the example shown in FIG. 1, for each of the green color filter layer 210G and the blue color filter layer 210B). This is to prevent a change in emission color due to the viewing angle at a high level by utilizing the directivity of light based on the principle of scattering. Specifically, the concave / convex shape is determined with a period of ½ or more of the wavelength of the light to be changed, thereby adjusting the concave / convex density, and changing the refractive index for each sub-pixel to direct the light emitted from each sub-pixel. Adjust gender. Here, in the example shown in FIG. 1, the period of the concavo-convex shape refers to a horizontal distance in the drawing between adjacent convex portions in each color filter layer 210 (G, B). For example, when the unevenness density of the uneven shape of the interface 1 is 0.83 to 0.91 piece / μm ² , the uneven density of the uneven shape of the interface 2 is 1.01 to 1.18 piece / μm ^2. Is preferred. By finely adjusting the unevenness density between the sub-pixels in this way, it is possible to reduce the difference in the directivity of light between the sub-pixels and to sufficiently prevent the emission color that varies depending on the viewing angle.

Here, the sub-pixel means a part corresponding to the light emitting part of the organic EL element part, that is, a part having the width of the transparent electrode 310 in the pixel (the whole of FIG. 1) as shown in FIG. . In addition, although the unevenness | corrugation is not attached | subjected at all to the interface of the red color filter layer 210R and transparent substrate 100 shown in FIG. 1, in this invention, the uneven | corrugated density in such an interface is set to 0, and also includes the said interface, This is interpreted as having different uneven density for each sub-pixel.

As a specific example of such a concavo-convex shape, it can be an array shape of a plurality of concave portions and convex portions having at least one period and smaller than the sub-pixel width. Moreover, as a specific means for making the uneven density of the uneven shapes of the interfaces 1 and 2 different, there is a means for attaching uneven shapes having different periods to each sub-pixel (for each of the interfaces 1 and 2).

Regarding the formation of the uneven shape of the interfaces 1 and 2, first, the unevenness is formed on the surface of the transparent substrate 100 corresponding to the pattern of the color filter layers 210G and 210B. Next, the selected color filter layers 210G and 210B are stacked on the pattern.

As a method of forming irregularities on the transparent substrate 100, a method generally used for surface roughening treatment, for example, a method of etching with a chemical agent, plasma or the like using a resist pattern as a mask can be used. Further, it is also possible to employ a sandblasting method, for example, a mechanical method of scratching the surface using comb teeth, or the like, using a mask and an abrasive.

When a glass substrate is used as the transparent substrate 100, a suitable irregularity is formed on the surface of the glass substrate by using an abrasive having an average particle size of 5 μm by sandblasting and treating for 2 to 8 seconds, preferably 3 to 7.5 seconds. Can be formed. By not excessively increasing the treatment time, it is possible to suppress the uneven density of the uneven shape from becoming excessive, and to prevent the brightness of the treatment surface from being impaired.

In the example illustrated in FIG. 1, the interface between the red color filter layer 210 </ b> R and the transparent substrate 100 is not provided with an uneven shape. The red color filter layer 210R can be laminated on the transparent substrate 100 by various known methods. For example, it can be formed by applying a known red color filter material by spin coating and performing patterning by photolithography.

(About components of organic EL display)
Hereinafter, among the constituent elements of the organic EL display shown in FIG. 1, elements other than the above-described substrate 100 will be described in detail.

Color filter layer 210
The color filter layer 210 is a layer for improving the color purity of light having a certain region of the incident light incident on the layer by blocking a specific wavelength. The color filter layer 210 (R, G, B) can be formed on the transparent substrate 100 using a material for a flat panel display. The color filter layer 210 has a structure in which a blue color filter layer that transmits a wavelength of 400 to 550 nm, a green color filter layer that transmits a wavelength of 500 to 600 nm, and a red color filter layer that transmits a wavelength of 600 nm or more are arranged. be able to.

These color filter layers are composed of a photosensitive resin layer in which a dye or pigment, preferably a pigment is dispersed. As the dispersed pigment, azo lake, insoluble azo, condensed azo, phthalocyanine, quinacridone, dioxazine, Indolinone, anthraquinone, berylone, thioin, berylene, and mixtures thereof are preferably used.

The color filter layer 210 has a stripe pattern composed of red (R), green (G), and blue (B) repetitions. Each pattern is transparent with a pattern width of 60 to 100 μm and a pattern interval of 70 to 90 μm. It is provided on one surface of the substrate 100. As a method for forming the color filter layer 210, a coating method can be used, and it is particularly preferable to use a photo process.

Light shielding layer 220
The light shielding layer 220 is formed for the purpose of improving the contrast by preventing the visible region from being transmitted between the color filter layers. The light shielding layer 220 is formed using a material for a normal flat panel display. As a method for forming the light shielding layer 220, a coating method can be used, and it is particularly preferable to use a photo process.

Planarization layer 230
The planarization layer 230 is a layer formed for the purpose of protecting the color filter layer 210 (R, G, B). Further, the planarizing layer 230 is formed so that a step generated by the color filter layer 210 and the light shielding layer 220 does not adversely affect the dimensional accuracy of each layer formed above the layers 210 and 220. Layer. For this reason, the planarization layer 230 needs to be formed by selecting a material and a process that are rich in light transmittance and do not deteriorate the color filter layer 210 (R, G, B).

As a material applicable to the planarization layer 230, a photocurable or photothermal combination type curable resin is subjected to light and / or heat treatment to generate radical species and ionic species to be polymerized or crosslinked to be insoluble and infusible. Is common. In addition, the photocurable or photothermal combination type curable resin is preferably soluble in an organic solvent or an alkaline solution before curing in order to perform patterning.

Specifically, as photocurable or photothermal combination type curable resin,
(1) A composition film composed of an acrylic polyfunctional monomer or oligomer having a plurality of acroyl groups and methacryloyl groups, and light or a thermal polymerization initiator is subjected to light or heat treatment to generate photo radicals or heat radicals for polymerization. What
(2) A composition comprising a polyvinyl cinnamate ester and a sensitizer, which is dimerized by light or heat treatment and crosslinked.
(3) A composition film composed of a chain or cyclic olefin and a bisazide generated by nitrene generation by light or heat treatment to be crosslinked with the olefin, and (4) a monomer having an epoxy group and a photoacid generator And a composition film obtained by polymerizing an acid (cation) by light or heat treatment.

In particular, when the photocurable or photothermal combination curable resin (1) is used, patterning is possible because of a photo process, which is also preferable in terms of reliability such as solvent resistance and heat resistance.

Other photocurable or photothermal combination type curable resins include polycarbonate (PC), polyethylene terephthalate (PET), polyethersulfone, polyvinyl butyral, polyphenylene ether, polyamide, polyetherimide, norbornene resin, and methacrylic resin. , Isobutylene maleic anhydride copolymer resin, cyclic olefin thermoplastic resin, epoxy resin, phenol resin, urethane resin, acrylic resin, vinyl ester resin, imide resin, urethane resin, urea resin, melamine resin, etc. Examples thereof include a curable resin, or a polymer hybrid containing a trifunctional or tetrafunctional alkoxysilane with polystyrene, polyacrylonitrile, polycarbonate, or the like.

As a method for forming the planarization layer 230, a coating method can be used, and it is particularly preferable to use a photo process.

Note that FIG. 1 is an example including the color filter layer 210, but when the color filter layer 210 is not included at all, an uneven shape is formed at the interface between the transparent substrate 100 and the planarization layer 230. Also in this case, a coating method can be used, and it is particularly preferable to use a photo process.

Red conversion layer 240
The color conversion layer is a photosensitive material in which a fluorescent dye having a function of causing the fluorescent dye to absorb incident light having a wavelength in the near ultraviolet region or visible region and emitting fluorescent light in a visible light region having a wavelength different from that of the incident light is dispersed. It consists of a functional resin layer. In the example shown in FIG. 1, only the red color conversion layer 240 is used among the red color conversion layer, the green color conversion layer, and the blue color conversion layer.

Examples of the fluorescent dye used in the red conversion layer 240 that absorbs light in the blue or blue-green region emitted from the organic EL element unit 300 and emits fluorescence in the red region include, for example, rhodamine B, rhodamine 6G, rhodamine 3B, Rhodamine 101, rhodamine 110, sulforhodamine, basic violet 11, basic red 2 and other rhodamine dyes, cyanine dyes, 1-ethyl-2- [4- (p-dimethylaminophenyl) -1,3-butadienyl]- Examples thereof include pyridine dyes such as pyridinium perchlorate (pyridine 1), and oxazine dyes. Various dyes such as direct dyes, acid dyes, basic dyes, and disperse dyes can be used as long as they exhibit fluorescence.

Although not used in the example shown in FIG. 1, as a fluorescent dye used for a green conversion layer that absorbs light in a blue to blue-green region emitted from the organic EL element unit 300 and emits fluorescence in a green region, for example, 3- (2'-benzothiazolyl) -7-diethylamino-coumarin (coumarin 6), 3- (2'-benzoimidazolyl) -7-diethylamino-coumarin (coumarin 7), 3- (2'-N-benzoimidazolyl) -7 A coumarin dye such as diethylamino-coumarin (coumarin 30), 2,3,5,6-1H, 4H-tetrahydro-8-trifluoromethylquinolidine (9,9a, 1-gh) coumarin (coumarin 153), Coumarin dyes such as Basic Yellow 51, phthalimide colors such as Solvent Yellow 11 and Solvent Yellow 116 And the like. Various dyes such as direct dyes, acid dyes, basic dyes, and disperse dyes can be used as long as they exhibit fluorescence.

The blue conversion layer is usually omitted because the light emitted from the organic EL element unit 300 has substantially the same wavelength region as the wavelength region selected by the blue color filter layer 210B, and is not used in the example shown in FIG. . Instead of omitting the blue conversion layer, a transparent photosensitive resin layer can be formed as a dummy.

The color conversion layer (red conversion layer 240 in the example shown in FIG. 1) can be formed by various dry processes, and is preferably formed by vacuum deposition because it can be formed without decomposing the organic material. As a heating method of the vacuum evaporation method, either a direct heating method or an indirect heating method can be used, and specifically, resistance heating, electron beam heating, infrared heating, or the like can be used. When forming a color conversion layer using a plurality of types of color conversion dyes, a preliminary mixture prepared by mixing a plurality of types of color conversion dyes in a predetermined ratio is prepared in advance, and co-evaporation is performed using the preliminary mixture. Can do. It is also possible to perform co-evaporation by arranging a plurality of types of color conversion dyes in separate heating sites and heating each color conversion dye separately. In particular, in the case of a plurality of types of color conversion dyes, when the characteristics such as vapor deposition rate and / or vapor pressure are greatly different, it is advantageous to use the latter method.

The film thickness of the color conversion layer (red conversion layer 240 in the example shown in FIG. 1) is preferably 1 μm or less from the viewpoint of exhibiting the function of the color conversion layer, and is preferably 200 nm to 1 μm. It is more preferable at the point which can utilize a layer effectively.

Gas barrier layer 250
The gas barrier layer 250 is a layer formed to prevent moisture and / or oxygen from entering the color conversion layer (the red conversion layer 240 in the case shown in the figure) from the outside. This is because the color conversion dye is an organic substance and thus is vulnerable to moisture and oxygen.

Here, the purpose of forming the gas barrier layer 250 is to protect the red color conversion layer 240, but in the example shown in FIG. 1, not only the red color conversion layer 240 but also the planarization layer 230 is protected. This structure is also effective for protecting the organic EL layer 320, which will be described later, since it is necessary to prevent moisture from being emitted from the color conversion filter unit 200.

As a material applicable to the gas barrier layer 250, a material having electrical insulating properties and a barrier property against a gas and an organic solvent and having high transparency in the visible region (transmittance in a range of 400 to 700 nm). 50% or more) can be used. Further, it is preferable to use a material having a film hardness (pencil hardness) of 2H or more, which is a hardness that can withstand the formation of a transparent electrode 310 and the like, which will be described later, formed on the gas barrier layer 250. The film hardness (pencil hardness) conforms to JIS K5600-5-4. As the specific gas barrier layer 250, for example, an inorganic oxide such as SiOx, SiNx, SiNxOy, AlOx, TiOx, TaOx, ZnOx, or an inorganic nitride can be used.

The formation method of the gas barrier layer 250 is not particularly limited, and a sputtering method, a CVD method, a vacuum deposition method, or the like can be used. In addition, the gas barrier layer 250 can be a single layer or a laminate including a plurality of layers. As a result, the color conversion filter unit 200 is formed on the transparent substrate 100.

Transparent electrode 310
Materials applicable to the transparent electrode 310 include ITO, tin oxide, indium oxide, IZO, zinc oxide, zinc-aluminum oxide, zinc-gallium oxide, or a dopant such as F or Sb added to these oxides. Conductive transparent metal oxides can be used. The transparent electrode 310 can be obtained by forming using a vapor deposition method, a sputtering method, or a chemical vapor deposition (CVD) method and then patterning using a photolithographic method or the like. Among such formation methods, it is particularly preferable to use a sputtering method.

The transparent electrode 310 can be either an anode or a cathode. When the transparent electrode 310 is used as a cathode, it is preferable to form a cathode buffer layer (not shown) between the transparent electrode 310 and the organic EL layer 320 to improve the electron injection efficiency for the organic EL layer 320. As a material applicable to the cathode buffer layer, an alkali metal such as Li, Na, K or Cs, an alkaline earth metal such as Ba or Sr, an alloy containing them, a rare earth metal, or a fluoride of these metals is used. be able to. The thickness of the cathode buffer layer is preferably 10 nm or less from the viewpoint of ensuring transparency. On the other hand, when the transparent electrode 310 is used as an anode, a conductive transparent metal oxide layer is provided between the transparent electrode 310 and the organic EL layer 320 to increase the hole injection efficiency for the organic EL layer 320. It is preferable to improve. Examples of materials applicable as the conductive transparent metal oxide include ITO, tin oxide, indium oxide, IZO, zinc oxide, zinc-aluminum oxide, zinc-gallium oxide, and oxides such as F or Sb. A material to which a dopant is added can be used.

Organic EL layer 320
The organic EL layer 320 includes at least an organic light emitting layer, and has a structure in which a hole injection layer, a hole transport layer, an electron transport layer and / or an electron injection layer are interposed as required. As a specific layer structure of the organic EL element portion, the following structure can be adopted.
(1) Anode / organic light emitting layer / cathode
(2) Anode / hole injection layer / organic light emitting layer / cathode
(3) Anode / organic light emitting layer / electron injection layer / cathode
(4) Anode / hole injection layer / organic light emitting layer / electron injection layer / cathode
(5) Anode / hole transport layer / organic light emitting layer / electron injection layer / cathode
(6) Anode / hole injection layer / hole transport layer / organic light emitting layer / electron injection layer / cathode
(7) Anode / hole injection layer / hole transport layer / organic light emitting layer / electron transport layer / electron injection layer / cathode
In the layer structures (1) to (7), the anode and the cathode are either the transparent electrode 310 or the reflective electrode 330.

As a material of each layer constituting the organic EL layer 320, a known material can be used. Moreover, each layer which comprises the organic EL layer 320 can be formed using arbitrary methods well-known in the said techniques, such as a vapor deposition method.

In the case of using the red conversion layer 240 as shown in FIG. 1, it is important that the organic EL layer 320 realizes light emission from blue to blue-green. Examples of materials applicable to the organic light emitting layer for obtaining blue to blue-green light emission include fluorescent brighteners such as benzothiazole, benzimidazole, or benzoxazole, metal chelated oxonium compounds, and styrylbenzene. It is preferable to use a compound or an aromatic dimethylidin compound. In the example shown in FIG. 1, the light emission of the organic light emitting layer can be white light as necessary. In this case, it is important to use a known red dopant.

On the other hand, although not shown in FIG. 1, when a green conversion layer is used as the color conversion layer, it is important that the light emission of the organic light emitting layer is changed from blue to red.

Reflective electrode 330
As a material applicable to the reflective electrode 330, it is preferable to use a metal with high reflectivity, an amorphous alloy with high reflectivity, or a microcrystalline alloy with high reflectivity. Examples of the highly reflective metal include Al, Ag, Mo, W, Ni, and Cr. Examples of the highly reflective amorphous alloy include NiP, NiB, CrP, and CrB. An example of the highly reflective microcrystalline alloy is NiAl.

The reflective electrode 330 can be either a cathode or an anode. When the reflective electrode 330 is used as a cathode, it is preferable to form a cathode buffer layer (not shown) between the reflective electrode 330 and the organic EL layer 320 to improve the electron injection efficiency for the organic EL layer 320. Alternatively, a material having a high reflectivity characteristic as described above and having a low work function relative to a metal, an amorphous alloy or a microcrystalline alloy, ie, an alkali metal such as lithium, sodium or potassium, or an alkali such as calcium, magnesium or strontium It is also preferable to add an earth metal and alloy it to improve the electron injection efficiency. On the other hand, when the reflective electrode 330 is used as an anode, a conductive transparent metal oxide layer is provided between the reflective electrode 330 and the organic EL layer 320 to increase the hole injection efficiency for the organic EL layer 320. It is preferable to improve. Examples of materials applicable as the conductive transparent metal oxide include ITO, tin oxide, indium oxide, IZO, zinc oxide, zinc-aluminum oxide, zinc-gallium oxide, and oxides such as F or Sb. A material to which a dopant is added can be used.

As a method for forming the reflective electrode 330, any means known in the technical field such as vacuum deposition, sputtering, ion plating, or laser ablation can be used depending on the material to be used. Unlike the example shown in FIG. 1, when the reflective electrode 330 made up of a plurality of partial electrodes is required, the reflective electrode 330 made up of the plurality of partial electrodes is formed using a mask that gives a desired shape. You can also.

In the example shown in FIG. 1, the reflective electrode 330 has a striped pattern that intersects the pattern of the transparent electrode 310, and this intersecting region forms a light emitting subpixel.

The organic EL display obtained as described above is bonded to a sealing glass (not shown) by UV curing in a dry nitrogen atmosphere in the glove box (an atmosphere in which both O ₂ concentration and H ₂ O concentration are 10 ppm or less). It seals using the contact bonding layer which consists of an agent.

[Organic EL display (Type 2)]
Next, another embodiment (type 2) of the present invention will be described with reference to FIG. In the following, only the overall configuration and differences from the above-described organic EL display (type 1) will be described in detail.

(Overall configuration)
In the organic EL display (top emission type) of the present invention, as shown in FIG. 2, the first laminate X in which the color conversion filter unit 200 is formed on the substrate 100 and the organic EL element unit 300 on the base 400 are formed. The second laminated body Y is bonded to the light incident surface of the color conversion filter unit 200 with the light emitting surface of the organic EL element unit 300 by a thermosetting adhesive layer 500. is there. The organic EL display shown in FIG. 2 includes a sealing material (not shown) that blocks the color conversion filter unit 200 and the organic EL element unit 300 from the outside air.

The transparent substrate 100 supports the components (the color filter layer 210, the light shielding layer 220, the planarization layer 230, the red color conversion layer 240, and the gas barrier layer 250) of the color conversion filter unit 200 that are sequentially formed thereon. Is a layer. The transparent substrate 100 is one that can withstand the conditions (solvent, temperature, etc.) used for forming these components. Other conditions for the transparent substrate 100 are the same as those of the transparent substrate 100 shown in FIG.

Various conditions for the color conversion filter unit 200 and the organic EL element 300 are the same as those of the transparent substrate 100 shown in FIG.

The substrate 400 is a component for supporting the organic EL element 300. As the substrate 400, a substrate that can withstand the conditions (solvent, temperature, etc.) used for forming the organic EL element 300 is used.
Other conditions for the substrate 400 are the same as those of the transparent substrate 100.

The adhesive layer 500 is a component used for bonding the first laminate X and the second laminate Y together. The adhesive layer 500 is not particularly limited as long as it has visible light transparency and can be formed without causing adverse effects such as damage to the red color conversion layer 240 and the organic EL layer 320. For example, a general thermoplastic resin, a thermosetting resin that can be cured by heat at room temperature to 120 ° C., a resin that can be cured by visible light, or a combination of heat and light can be used.

(Manufacturing method of organic EL display (type 2))
First, similarly to the organic EL display (type 1) shown in FIG. 1, a color filter 210, a light shielding layer 220, a planarization layer 230, a red color conversion layer 240, and a gas barrier layer 250 are sequentially formed on the substrate 100. 1 laminate X is obtained.

Next, separately from the first stacked body X, the reflective electrode 330, the organic EL layer 320, and the transparent electrode 310 are sequentially formed on the substrate 400 to obtain the second stacked body Y. The formation mode of the reflective electrode 330 and the like on the substrate 400 is performed in accordance with the formation mode of the corresponding component in the organic EL display (type 1) shown in FIG.

Further, the first stacked body X and the second stacked body Y are interposed through the thermosetting adhesive layer 500 in a state where the light incident surface of the color conversion filter unit 200 faces the light emitting surface of the organic EL element unit 300. to paste together.

Finally, the obtained organic EL display was subjected to a sealing layer made of a UV curable sealing agent (not shown) under a dry nitrogen atmosphere (an atmosphere in which both O ₂ concentration and H ₂ O concentration were 10 ppm or less) in the glove box. Is used to seal the color conversion filter unit 200 and the organic EL element unit 300.

Hereinafter, the effects of the present invention will be demonstrated by examples and comparative examples. The following examples and comparative examples all relate to an organic EL display in which 160 pixels including R, G, and B subpixels are formed at a pitch of 0.33 mm in the vertical direction and 120 in the horizontal direction.

<Production of organic EL display>
Example 1
The organic EL display of Example 1 was a display of the type shown in FIG. A glass substrate of 200 mm × 200 mm × 0.7 mm was prepared. A dry etching method (C ₄ F ₈ : 16 msccm, CH ₂ F ₂ : 16 sccm, gas pressure 0.8 Pa, and power 2 kW) is used with a Cr film (film thickness 100 nm) first patterned at a predetermined pitch as a mask. The blue subpixel area on the color filter layer side of the substrate is formed into a right-cone-shaped irregularity with a depth of 0.6 μm and a pitch of 0.2 μm, and then the green subpixel area is formed with a depth of 0.4 μm and a pitch of 0. A substrate 100 having a 3 μm right conical unevenness was obtained.

On the substrate 100, a light-shielding layer coating solution (CK8400L manufactured by Fuji Film ARCH) was applied to the entire surface by a spin coating method, and dried at 80 ° C. by heating. Thereafter, a pattern having a sub-pixel size (vertical direction of 80 μm × horizontal direction of 300 μm, thickness direction of 1 μm) was formed at a pitch of 330 μm by using a photolithography method, and the light shielding layer 220 was laminated on the substrate 100.

Regarding the formation of the blue color filter layer 210B, a blue color filter material (manufactured by Fuji Film ARCH: Color Mosaic CB-7001) was applied on the substrate 100 by spin coating, and patterning was performed by photolithography. Specifically, the substrate 100 formed into a conical unevenness having a depth of 0.6 μm and a pitch of 0.2 μm was traced. As a result, the substrate side of the blue color filter layer 210B has an area size of 80 μm × 300 μm and a thickness of 0.6 μm in depth, a pitch of 0.2 μm, and an average density of 0.88 pieces / μm ² formed into a right cone shape. A 2 μm line pattern was obtained.

For the formation of the green color filter layer 210G, a green color filter material (manufactured by Fuji Film ARCH: Color Mosaic CG-7001) was applied on the substrate 100 by spin coating, and patterning was performed by photolithography. Specifically, the substrate 100 formed into a conical unevenness having a depth of 0.4 μm and a pitch of 0.3 μm was traced. As a result, the substrate side of the green color filter layer 210G is an area size of 80 μm × 300 μm, formed into a conical unevenness having a depth of 0.4 μm, a pitch of 0.3 μm, and an average density of 1.99 / μm ² A 2 μm line pattern was obtained.

For the formation of the red color filter layer 210R, a red color filter material (manufactured by Fuji Film ARCH: Color Mosaic CR-7001) was applied on the substrate 100 by spin coating, and patterning was performed by photolithography. Specifically, a line pattern having an area size of 80 μm × 300 μm and a film thickness of 2 μm was obtained.

Next, the planarization layer 230 was formed by applying a planarization layer material (Nippon Steel Chemical Co., Ltd .: V-259PA) on the color filter layer 210 and the light shielding layer 220 by spin coating. The thickness of the planarizing layer 230 in the region in contact with the light shielding layer 220 was 2.5 μm. Incidentally, when a planarization film was separately formed under the same conditions on a glass substrate and the refractive index was measured, it was found that the planarization layer of this example had a refractive index of 1.5.

The layered product having the flattening layer 230 or less obtained as described above is heated to 200 ° C. for 20 minutes under a dry nitrogen atmosphere (moisture concentration of 1 ppm or less) to remove residual moisture. Removed.

This laminate was attached to a vacuum deposition apparatus, and DCM-R was deposited at a deposition rate of 0.3 Å / s under a pressure of 1 × 10 ⁻⁴ Pa to form a red conversion layer 240 having a thickness of 500 nm. . Incidentally, when a DCM-R film was separately formed on a glass substrate under the same conditions and the refractive index was measured, it was found that the red conversion layer of this example had a refractive index of 1.9.

Further, a 300 nm-thick SiNH film was laminated by using a plasma CVD method to obtain a gas barrier layer 250. 100 SCCM SiH ₄ , 500 SCCM NH ₃ , and 2000 SCCM N ₂ were used as source gases, and the gas pressure was set to 80 Pa. Moreover, 0.5 kW of 27 MHz RF power was applied as plasma generation power. Incidentally, when a SiNH film was separately formed on a glass substrate under the same conditions and the refractive index was measured, it was found that the gas barrier layer of this example had a refractive index of 1.95.

On the substrate 100 and the color conversion filter part 200 formed sequentially as described above, the transparent electrode 310 / organic EL layer 320 (hole injection layer / hole transport layer / organic light emitting layer / electron transport layer) / reflection electrode 330 The organic EL element part 300 which consists of was formed.

The transparent electrode 310 formed an In—Zn oxide pattern. An In—Zn oxide film having a thickness of 200 nm was formed at room temperature by DC sputtering. An In—Zn oxide target was used as the sputtering target, and Ar and oxygen were used as the sputtering gas. After patterning the resist by photolithography, patterning was performed using oxalic acid as an etchant to form a pattern with a wiring width of 100 μm. After patterning, drying treatment (150 ° C.) and UV treatment (room temperature and 150 ° C.) were performed.

After the UV treatment, the laminate is mounted in a resistance heating vapor deposition apparatus, and a hole injection layer, a hole transport layer, an organic light emitting layer, and an electron injection layer are sequentially formed without breaking the vacuum to form an organic EL layer 320. did. During film formation, the internal pressure of the vacuum chamber was reduced to 1 × 10 ⁻⁵ Pa. As the hole injection layer, copper phthalocyanine (CuPc) was laminated to a thickness of 100 nm. As the hole transport layer, 4,4′-bis [N- (1-naphthyl) -N-phenylamino] biphenyl (α-NPD) was laminated to a thickness of 20 nm. As the organic light emitting layer, 4,4′-bis (2,2′-diphenylvinyl) biphenyl (DPVBi) was laminated to 30 nm. The electron injection layer was formed by laminating 20 nm of aluminum chelate (Alq).

Next, a reflection made of a Mg / Ag (10: 1 weight ratio) layer having a thickness of 200 nm is used by using a mask capable of obtaining a stripe pattern having a width of 0.30 mm and a gap of 0.03 mm perpendicular to the line of the transparent electrode 310. The electrode 330 was formed without breaking the vacuum. Using a dispenser robot, a UV curable adhesive (trade name 30Y-437, manufactured by ThreeBond Co., Ltd.) in which beads having a diameter of 6 μm were dispersed was placed on the outer periphery of the laminate thus obtained using a dispenser robot in a dry nitrogen atmosphere inside the glove box. The organic EL display of Example 1 was obtained by bonding using the sealing glass applied to the substrate and irradiating with 100 mW / cm ² ultraviolet rays for 30 seconds to cure the outer peripheral sealing layer.

(Example 2)
The organic EL display of Example 2 was a display of the type shown in FIG. The formation of the substrate 100 and the sequential formation of the light shielding layer 220, the color filter layer 210, the planarization layer 230, the red color conversion layer 240, and the gas barrier layer 250 on the substrate 100 are performed in the same manner as in Example 1. 1 laminate X was obtained.

Next, a glass substrate as a substrate 400 was separately prepared, and a reflective electrode 330 made of indium / tin oxide (ITO) having a thickness of 200 nm was formed by sputtering and photolithography. The shape of the reflective electrode 330 was a stripe pattern with a wiring width of 100 μm extending in the vertical direction.

Furthermore, the laminated body in which the reflective electrode 330 is formed on the substrate 400 is mounted in a resistance heating vapor deposition apparatus, and the electron injection layer, the organic EL light emitting layer, the hole transport layer, and the hole injection layer are set in a vacuum chamber. The organic EL layer 320 was formed by sequentially stacking the layers while maintaining the pressure at 1 × 10 ⁻⁵ Pa.
Thereafter, using a mask on which a stripe pattern orthogonal to the reflective electrode 330 having a pattern width of 0.30 mm and an inter-pattern distance of 0.03 mm is obtained on the organic EL layer 320, the Mg / An Ag layer (weight ratio: Mg: Ag = 10: 1) was formed as the transparent electrode 310.

Finally, a passivation layer (not shown) made of SiN having a thickness of 500 nm was formed so as to cover the stacked body from the base body 400 to the transparent electrode 310, and a second stacked body Y was obtained.

The first laminated body X and the second laminated body Y obtained in this manner were carried into a bonding apparatus managed with a moisture concentration of 1 ppm and an oxygen concentration of 1 ppm. Using a dispenser robot, a UV curable adhesive (trade name 30Y-437, manufactured by ThreeBond Co., Ltd.) in which beads having a diameter of 6 μm are dispersed is applied to the first laminate X as an outer peripheral sealing layer, and at the center. A predetermined amount of a thermosetting adhesive was dropped, and the atmosphere was removed with a vacuum of 1 Pa in a bonding apparatus. Next, the gas barrier layer 250 and a passivation layer (not shown) were opposed to each other, the laminated body Y was placed on the upper surface of the passivation layer, and the laminated bodies X and Y were bonded together by pressure bonding. After protecting with a mask except for the outer periphery sealing part, 100 mW / cm ² ultraviolet ray was irradiated for 30 seconds to cure, then heating at 100 ° C. for 1 hour to heat the outer periphery sealing part and the thermosetting adhesive Curing was performed to obtain an organic EL display of Example 2.

(Comparative Example 1)
The organic EL display of Comparative Example 1 was a display of the type shown in FIG. A glass substrate of 200 mm × 200 mm × 0.7 mm was prepared. First, a light shielding layer coating solution (CK8400L manufactured by Fuji Film ARCH) was applied on the entire surface of the substrate 100 by a spin coat method and dried by heating at 80 ° C. Then, using a photolithographic method, at a pitch of 330 μm, A pattern with a subpixel size (vertical direction 80 μm × horizontal direction 300 μm, thickness direction 1 μm) was formed, and a light shielding layer 220 was laminated on the substrate 100.

For the formation of the blue color filter layer 210B, a blue color filter material (manufactured by Fuji Film ARCH: Color Mosaic CB-7001) was applied on the substrate 100 by spin coating, and patterning was performed by photolithography. Specifically, a line pattern having an area size of 80 μm × 300 μm and a film thickness of 2 μm was obtained.

For the formation of the green color filter layer 210G, a green color filter material (manufactured by Fuji Film ARCH: Color Mosaic CG-7001) was applied on the substrate 100 by a spin coating method, and patterning was performed by a photolithographic method. Specifically, a line pattern having an area size of 80 μm × 300 μm and a film thickness of 2 μm was obtained.

Thereafter, the red color filter layer 210R, the flattening layer 230, the red color conversion layer 240, the gas barrier layer 250, the transparent electrode 310, the organic EL layer 320, and the reflective electrode 330 are formed and sealed in the same manner as in the example. The organic EL display of Comparative Example 1 was obtained.

(Comparative Example 2)
The organic EL display of Comparative Example 2 was a display of the type shown in FIG. A glass substrate of 200 mm × 200 mm × 0.7 mm was prepared. A dry etching method (C ₄ F ₈ : 16 msccm, CH ₂ F ₂ : 16 sccm, gas pressure 0.8 Pa, and power 2 kW) is used with a Cr film (film thickness 100 nm) first patterned at a predetermined pitch as a mask. Thus, a substrate 100 was obtained in which the blue subpixel area and the green subpixel area on the color filter layer side of the substrate were formed in a conical irregularity having a depth of 0.6 μm and a pitch of 0.2 μm.

On the substrate 100, a light-shielding layer coating solution (CK8400L manufactured by Fuji Film ARCH) was applied to the entire surface by a spin coating method, and dried at 80 ° C. by heating. Thereafter, a pattern having a sub-pixel size (vertical direction of 80 μm × horizontal direction of 300 μm, thickness direction of 1 μm) was formed at a pitch of 330 μm by using a photolithography method, and the light shielding layer 220 was laminated on the substrate 100.

Regarding the formation of the blue color filter layer 210B, a blue color filter material (manufactured by Fuji Film ARCH: Color Mosaic CB-7001) was applied on the substrate 100 by spin coating, and patterning was performed by photolithography. Specifically, the substrate 100 formed into a conical unevenness with a depth of 0.6 μm and a pitch of 0.2 μm was traced. As a result, the substrate side of the blue color filter layer 210B has an area size of 80 μm × 300 μm and a thickness of 0.6 μm in depth, a pitch of 0.2 μm, and an average density of 0.88 pieces / μm ² formed into a right cone shape. A 2 μm line pattern was obtained.

For the formation of the green color filter layer 210G, a green color filter material (manufactured by Fuji Film ARCH: Color Mosaic CG-7001) was applied on the substrate 100 by spin coating, and patterning was performed by photolithography. Specifically, the substrate 100 formed into a conical unevenness having a depth of 0.6 μm and a pitch of 0.2 μm was traced. As a result, the substrate side of the green color filter layer 210G is an area size of 80 μm × 300 μm formed in a right-cone-shaped unevenness with a depth of 0.6 μm, a pitch of 0.2 μm, and an average density of 0.88 / μm ^2. A 2 μm line pattern was obtained.

Thereafter, the red color filter layer 210R, the flattening layer 230, the red color conversion layer 240, the gas barrier layer 250, the transparent electrode 310, the organic EL layer 320, and the reflective electrode 330 are formed and sealed in the same manner as in the example. The organic EL display of Comparative Example 2 was obtained.

<Evaluation items>
The organic EL displays of Examples 1 and 2 and Comparative Examples 1 and 2 were subjected to subjective light emission evaluation observed from the front and oblique directions when D65 white light was lit. The results are shown in Table 1. The oblique observation is observation from a position at 45 degrees with respect to the normal line of the organic EL display screen.

From the results of Table 1, in Examples 1 and 2 in which the interface between the substrate 100 and the blue and green color filter layers 210B and 210G has different uneven density, the bottom emission type (Example 1) and the top emission type (Example 2). In either case, it was found that there was no change in the light emission color of the screen depending on the observation angle.

On the other hand, in Comparative Example 1 where the interface between the substrate 100 and the blue and green color filter layers 210B and 210G is not uneven, it was found that the change in the emission color of the screen depending on the observation angle was significant.

Further, it was found that in the comparative example 2 in which the interface between the substrate 100 and the blue and green color filter layers 210B and 210G has the same uneven density, the emission color of the screen changes depending on the observation angle.

Incidentally, no change was seen in the luminance and chromaticity in Examples 1 and 2 and Comparative Examples 1 and 2.

Therefore, the organic EL displays of Examples 1 and 2 have a structure in which the unevenness density is adjusted for each of R, G, and B at the interface between the substrate and the color filter, so that the luminance and chromaticity are maintained. It has been found that the difference in directivity of light between G, B and B can be reduced.

The above results are examples in which the interface between the substrate and the color filter is appropriately adjusted, but when the color filter is not present, an equivalent result is obtained in an example in which the interface between the substrate and the planarization layer is appropriately adjusted. Expected to be obtained.

The present invention has a predetermined shape at the interface between the substrate and the color filter or the flattening layer, thereby finely adjusting the difference in directivity of light between different-colored subpixels and increasing the change in emission color depending on the viewing angle. Can be prevented by level. Therefore, the present invention is promising in that it can provide various electronic devices such as a mobile phone having a display unit that does not change the emission color depending on the viewing angle.

Claims (10)

1. A substrate, a color conversion filter unit including a planarization layer and at least one color conversion layer, and an organic EL element unit having a plurality of light emitting units, wherein a plurality of subpixels are defined by the plurality of light emitting units. In organic EL displays,
   An organic EL display comprising an interface having a concavo-convex shape between the substrate and the planarization layer, wherein the concavo-convex shape has a different concavo-convex density for each sub-pixel.
2. A first laminate including a substrate, a color conversion filter portion including a planarization layer and at least one color conversion layer, and a second laminate including an organic EL element portion having a base and a plurality of light-emitting portions; In an organic EL display in which a plurality of sub-pixels are defined by the plurality of light emitting units,
   An organic EL display comprising an interface having a concavo-convex shape between the substrate and the planarization layer, wherein the concavo-convex shape has a different concavo-convex density for each sub-pixel.
3. The organic EL display according to claim 1, further comprising at least one color filter layer between the substrate and the planarizing layer.
4. 4. The organic EL display according to claim 1, wherein the concavo-convex shape is an array shape of a plurality of concave portions and convex portions having at least one period and smaller than the sub-pixel width.
5. 5. The organic EL display according to claim 1, wherein the uneven shape has a different period for each sub-pixel.
6. Including a step of forming a color conversion filter portion including a planarization layer and at least one color conversion layer on a substrate, and a step of forming an organic EL element portion having a plurality of light emitting portions on the color conversion filter portion, A method of manufacturing an organic EL display in which a plurality of subpixels are defined by the plurality of light emitting units,
   A method of manufacturing an organic EL display, comprising: forming a concavo-convex shape on a substrate surface in contact with the planarizing layer; and adjusting the concavo-convex shape to a different concavo-convex density for each subpixel.
7. Forming a color conversion filter portion including a planarizing layer and at least one color conversion layer on a substrate to obtain a first laminate, and forming an organic EL element portion having a plurality of light emitting portions on a substrate. An organic EL display including a step of obtaining a second stacked body and a step of bonding the first stacked body and the second stacked body, wherein a plurality of sub-pixels are defined by the plurality of light emitting portions. A manufacturing method of
   A method of manufacturing an organic EL display, comprising: forming a concavo-convex shape on a substrate surface in contact with the planarizing layer; and adjusting the concavo-convex shape to a different concavo-convex density for each subpixel.
8. 8. The method of manufacturing an organic EL display according to claim 6, wherein at least one color filter layer is further formed between the substrate and the planarizing layer.
9. The organic EL display according to any one of claims 6 to 8, wherein the uneven shape is adjusted to at least one cycle to form an array shape of a plurality of recesses and protrusions smaller than the sub-pixel width. Production method.
10. 10. The method of manufacturing an organic EL display according to claim 6, wherein the uneven shape is adjusted to a different period for each sub-pixel.

Images