JP2006107761A - Color filter with color conversion function and organic el display using it - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a filter of a color conversion system, and a display, with a manufacturing process simplified and at the same time enabling high-definition patterning, and capable of improving color conversion efficiency concerning each primary color. <P>SOLUTION: The color filter with a color conversion function includes a transparent substrate, a plurality of kinds of color filter layers formed on the transparent substrate, and a color conversion layer containing at least one color conversion element, integrally formed covering the plurality of kinds of color filter layers with a flat surface. At least one color conversion element absorbs a part of a wave range of incident light, irradiates light of a wave range different from that absorbed, and a part of the plurality of color filter layers is thicker than the other part. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a method for manufacturing a color conversion filter that enables multicolor display. The color conversion filter can be used for display of image sensors, personal computers, word processors, televisions, facsimiles, audio, video, car navigation, electronic desk calculators, telephones, portable terminals and industrial measuring instruments. is there.

  In recent years, color conversion that absorbs near-ultraviolet light, blue light, blue-green light, or white light and performs wavelength distribution conversion to emit light in the visible light range is an example of a method for multicoloring or full color display. A color conversion method using a dye as a filter has been studied (see Patent Documents 1 and 2). When the color conversion method is used, the light emission color of the light source is not limited to white, so that the degree of freedom in selecting the light source can be increased. For example, green and red light can be obtained by wavelength distribution conversion using a blue light emitting organic EL light emitting element. Therefore, the possibility of constructing a full-color light-emitting display using a more efficient light source and using weak energy rays such as near-ultraviolet light or visible light has been studied (Patent Literature). 3).

  An important practical issue as a color display is to provide a color conversion filter having high color conversion efficiency in addition to long-term stability including fine color display function and color reproducibility. . However, if the concentration of the color conversion dye is increased in order to increase the color conversion efficiency, a decrease in efficiency due to so-called density quenching and decomposition of the color conversion dye over time occur, so a color conversion layer containing the color conversion dye The present situation is that a desired color conversion efficiency is obtained by increasing the thickness. In order to prevent concentration quenching and decomposition of color conversion dyes, introduction of bulky substituents into the dye mother nucleus has been studied (see Patent Documents 4 to 6). In addition, mixing quenchers has also been studied for preventing decomposition of color conversion pigments (see Patent Document 7).

Japanese Patent Application Laid-Open No. 08-279394 Japanese Patent Laid-Open No. 08-286033 JP 09-80434 A JP-A-11-279426 JP 2000-44824 A JP 2001-164245 A JP 2002-231450 A JP 05-134112 A JP 07-218717 A Japanese Patent Laid-Open No. 07-306311 JP 05-119306 A Japanese Patent Application Laid-Open No. 07-104114 JP 07-48424 A Japanese Patent Laid-Open No. 06-300910 Japanese Patent Laid-Open No. 07-128519 JP 09-330793 A Japanese Patent Laid-Open No. 08-27934 Japanese Patent Laid-Open No. 05-36475 Monthly Display, 1997, Volume 3, Issue 7

  In order to increase the definition of a multi-color or full-color display using a color conversion method, it is necessary to pattern the color conversion layer with a high definition. However, for example, when patterning is performed such that the width of one pattern is smaller than the film thickness, pattern shape reproducibility or pattern deformation in a subsequent process becomes a problem. In addition, when patterning by ordinary photolithography is performed, a coating process, an exposure process with mask alignment, and a development process are required for the color conversion layers of the respective colors. For example, in order to obtain a full color display, at least red, green and blue color conversion layers are required, so that the manufacturing process requires many steps and becomes complicated. Further, when forming a multi-color or full-color display by a color conversion method, it is one of the important issues that have existed before to improve the efficiency of color conversion for each primary color (for example, RGB).

  Accordingly, an object of the present invention is to provide a method for manufacturing a color conversion filter that simplifies the manufacturing process and at the same time enables high-definition patterning and can improve the efficiency of color conversion for each primary color. To do.

  The color filter with a color conversion function according to the first embodiment of the present invention includes a transparent substrate, a plurality of types of color filter layers formed on the transparent substrate, and at least one color conversion pigment, and the plurality of types of colors. A color conversion layer having a flat surface and integrally formed covering the filter layer, wherein the at least one color conversion dye absorbs a part of the wavelength range of incident light and has a wavelength different from the absorbed wavelength range In this case, a part of the plurality of kinds of color filter layers is thicker than the other color filter layers. Here, it is preferable that light incident on the color conversion layer is blue or blue-green light, and the at least one color conversion dye emits light including a spectrum in a red region. Particularly preferably, the plurality of types of color filter layers are composed of a red color filter layer, a green color filter layer, and a blue color filter layer, and the green color filter layer and the blue color filter layer are formed from the red color filter layer. It is desirable to form a thick film. In this embodiment, the color conversion layer is preferably a layer in which the at least one color conversion pigment is dispersed in a matrix resin, and may function as a protective layer for the plurality of types of color filters. Furthermore, you may further provide the gas barrier layer which covers the said color conversion layer.

  The organic EL display according to the second embodiment of the present invention includes a transparent substrate, a plurality of types of color filter layers formed on the transparent substrate, and at least one color conversion dye. A color conversion layer having a flat surface, a transparent electrode, an organic EL layer including at least an organic light-emitting layer, and a reflective electrode, wherein the at least one color conversion dye It absorbs a part of the wavelength range, emits light in a wavelength range different from the absorbed wavelength range, and a part of the plurality of kinds of color filter layers is thicker than the other color filter layers. Here, it is preferable that the organic light emitting layer emits blue to blue-green light, and the at least one color conversion dye emits light including a spectrum in a red region. Particularly preferably, the plurality of types of color filter layers are composed of a red color filter layer, a green color filter layer, and a blue color filter layer, and the green color filter layer and the blue color filter layer are formed from the red color filter layer. It is desirable to form a thick film. In this embodiment, the color conversion layer is preferably a layer in which the at least one color conversion pigment is dispersed in a matrix resin, and may function as a protective layer for the plurality of types of color filters. Furthermore, you may further provide the gas barrier layer which covers the said color conversion layer.

  As described above, the color filter with a color conversion function of the present invention has unique advantages as a color filter for display. In this embodiment, light emitted from a light source that can be independently controlled at positions corresponding to sub-pixels provided in a matrix is changed in hue by the color conversion layer and becomes light including a spectrum in the red region. With such a configuration, the blue or blue-green light of the backlight source can be converted into light that includes the spectrum in the red region simply by forming a single color conversion layer, thus simplifying the process. Cost reduction by making it possible. In addition, when the display has a higher definition, the color conversion layer can be formed integrally without patterning, thereby preventing problems such as pattern shape reproducibility and deformation.

  Further, light including the spectrum of the red region is incident on each color filter of the sub-pixel. For blue to green sub-pixels, the color filter is thickened to make the color conversion layer relatively thin, and the amount of hue change in the color conversion layer is reduced to reduce the blue color contained in the backlight. In addition, the green component can be used more effectively. On the other hand, in the red sub-pixel, by reducing the thickness of the color filter and relatively increasing the thickness of the color conversion layer, the amount of hue change in the color conversion layer is increased, and the spectrum of the red region is increased. More light is obtained. Therefore, it is possible to emit red light with higher luminance in the red subpixel.

  The color filter with a color conversion function of the first embodiment of the present invention is a laminate in which a plurality of types of color filter layers 2 and a color conversion layer 3 containing a color conversion dye (CCM) are provided on a transparent substrate 1. Is the body. FIG. 1 illustrates the case where three types of color filter layers (red 2R, green 2G, and blue 2B) are provided. The color conversion layer 3 functions as a layer that changes the hue of incident light from the light source. Specifically, the color conversion dye in the color conversion layer 3 absorbs light in a part of the wavelength range of incident light, emits light in a wavelength range different from the absorption wavelength range, and the color conversion dye does not absorb. The light of the different wavelength range and the light emitted by the color conversion dye are combined to emit light of different hues. More specifically, the color conversion layer 3 absorbs light in a part of the wavelength range of the incident light and emits light including a lot of spectrum in the wavelength range that is not substantially included in the incident light. If it takes, the light which radiate | emits the color conversion layer 3 can be made into the light (for example, the light containing all the spectrum of three primary colors, white light) containing a wider range spectrum. In the present invention, “substantially not contained in incident light” means that it does not exist at an intensity that affects the hue of incident light. For example, by using blue or blue-green light as incident light, and converting part of the light in the blue wavelength range into light that includes the spectrum in the red region with a color conversion dye, the spectrum of the emitted light is changed from the incident light. Can also be a wide range.

  The transparent substrate 1 needs to be transparent to visible light (wavelength 400 to 700 nm), preferably to light converted by the color conversion layer 3. Further, the transparent substrate 1 should be able to withstand the conditions (solvent, temperature, etc.) used for forming the color conversion layer 3 and other layers (described later) provided as necessary, and further to improve dimensional stability. It is preferable that it is excellent. Preferred materials for the transparent substrate 1 include glass and resins such as polyethylene terephthalate and polymethyl methacrylate. Borosilicate glass or blue plate glass is particularly preferable.

  The color filter layer 2 is a layer that transmits only light in a desired wavelength range. The color filter layer 2 is effective in blocking light transmitted through the color conversion layer 3 and obtaining light in a desired wavelength region (hue) from the light subjected to wavelength distribution conversion in the color conversion layer 3. The color filter layer 2 contains a pigment and a photosensitive resin. As the dye, it is preferable to use a pigment having high light resistance. The photosensitive resin includes (1) a composition comprising an acrylic polyfunctional monomer and oligomer having a plurality of acryloyl groups and methacryloyl groups, and a photopolymerization initiator, and (2) a composition comprising a polyvinylcinnamic acid ester and a sensitizer. And (3) a composition comprising a chain or cyclic olefin and bisazide (nitrene is generated to crosslink the olefin), (4) a composition comprising an epoxy group-containing monomer and a photoacid generator, etc. including. For example, the color filter layer 2 may be formed using a commercially available color filter material for liquid crystal (such as a color mosaic manufactured by Fuji Film Arch).

  The color filter layer 2 also has a function of relatively changing the thickness of the color conversion layer 3 formed thereon by changing the thickness thereof. In the present invention, the color filter layer that transmits the spectrum included in the incident light is thickened, and the color filter layer that is not substantially included in the incident light and transmits the spectrum obtained by wavelength distribution conversion by the color conversion layer is thinned. With such a configuration, in the color filter layer that transmits the spectrum included in the incident light, the color conversion layer 3 formed on the color filter layer is relatively thin, and the wavelength distribution conversion amount by the color conversion layer 3 is reduced. Thus, the spectrum included in the incident light can be used more effectively. On the other hand, in the color filter layer that transmits the spectrum obtained by the wavelength distribution conversion by the color conversion layer that is not substantially contained in the incident light, the color conversion layer 3 formed thereon is relatively thick to perform the color conversion. By increasing the wavelength distribution conversion amount in the layer 3, it is possible to increase the spectrum transmitted through the color filter layer and realize higher luminance.

  For example, when blue or blue-green light is used as incident light to obtain blue (B), green (G) and red (R) light as shown in FIG. 1, the blue color filter layer 2B and the green color are obtained. It is desirable to make the thickness of the filter layer 2G larger than the thickness of the red color filter layer 2R. The red color filter layer 2R depends on the pigment content, but preferably has a thickness of about 1 to 1.5 μm. On the other hand, the blue color filter layer 2B and the green color filter layer 2G are preferably at least twice the thickness of the red color filter layer 2R, and are desirably about 2 to 3 μm (of course, the pigment content is also high). Dependent). By setting the thickness of each color filter layer in such a range, the upper surface of the color conversion layer 3 formed thereon is planarized (that is, the thickness of the color conversion layer 3 on each color filter layer is increased). At the same time as performing (control), it becomes possible to efficiently emit light having a desired spectrum from each color filter layer.

  Optionally, a black mask 5 (see FIG. 2) that does not transmit visible light may be provided between and / or around the plurality of types of color filter layers 2 to improve the contrast ratio. The black mask 5 is obtained by dispersing a black pigment or dye in a resin, and can be formed using, for example, a commercially available black mask material for liquid crystal.

  The color conversion layer 3 is a layer made of a color conversion dye and a matrix resin and having a flat surface. The color conversion dye is a dye that converts the wavelength distribution of incident light and emits light having a spectrum in a wavelength region that is not substantially included in the incident light, and preferably converts the wavelength distribution of blue to blue-green light. Is a dye that emits light including a spectrum of a red region transmitted through the red color filter layer 2R. The color conversion layer 3 may contain a plurality of color conversion dyes to adjust the spectrum of the obtained wavelength region. Alternatively, a first color conversion dye that converts blue to blue-green light into light including a spectrum in the green region, and light including the spectrum in the green region in addition to blue to blue-green light is converted into a spectrum in the red region. The efficiency of the wavelength distribution conversion of incident light may be improved by using in combination with the second type color conversion dye that converts the light to contained light.

  Examples of color conversion dyes that absorb light in the blue to blue-green region and emit light including a spectrum in the red region include rhodamine B, rhodamine 6G, rhodamine 3B, rhodamine 101, rhodamine 110, sulforhodamine, basic violet 11, and basic. Rhodamine dyes such as red 2, cyanine dyes, pyridine dyes such as 1-ethyl-2- [4- (p-dimethylaminophenyl) -1,3-butadienyl] -pyridinium perchlorate (pyridine 1), or Contains oxazine dyes.

  Examples of the color conversion dye that absorbs light in the blue to blue-green region and emits light including a spectrum in the green region include 3- (2′-benzothiazolyl) -7-diethylamino-coumarin (coumarin 6), 3- ( 2'-Benzimidazolyl) -7-diethylamino-coumarin (coumarin 7), 3- (2'-N-methylbenzimidazolyl) -7-diethylamino-coumarin (coumarin 30), 2,3,5,6-1H, 4H- Coumarin-based dyes such as tetrahydro-8-trifluoromethylquinolidine (9,9a, 1-gh) coumarin (coumarin 153), or basic yellow 51 which is a coumarin dye-based dye, and further, solvent yellow 11 and solvent yellow 116 Including naphthalimide dyes.

  Even if it is a thing other than the above-mentioned pigment | dye, (1) Various dyes (a direct dye, an acid dye, a basic dye, a disperse dye, etc.) can be used on the condition of performing desired wavelength distribution conversion.

  The matrix resin that can be used for the color conversion layer 3 includes polycarbonate, polyester (polyethylene terephthalate, etc.), polyethersulfone, polyvinyl butyral, polyphenylene ether, in addition to those obtained by curing the photosensitive resin for the color filter layer described above. Polyamide, polyetherimide, norbornene resin, methacrylic resin, isobutylene-maleic anhydride copolymer resin, cyclic olefin resin, polyvinyl chloride, vinyl chloride-vinyl acetate copolymer resin, alkyd resin, aromatic sulfonamide resin, etc. Thermoplastic resins such as epoxy resins, phenol resins, urethane resins, acrylic resins, vinyl ester resins, imide resins, urethane resins, urea resins, melamine resins; Ronitoriru includes such a polycarbonate, a polymer hybrid or the like containing a trifunctional or tetrafunctional alkoxysilane. A mixture of these resins may be used as the matrix resin.

  In the present invention, it is preferable to use 0.2 μmol or more, preferably 1 to 20 μmol, more preferably 3 to 15 μmol of a color conversion dye per 1 g of the matrix resin used. Further, the color conversion layer 3 has a film thickness of 5 μm or more, preferably 5 to 15 μm (a film thickness of a portion where no color filter layer is provided, or a film thickness on the upper surface of the black mask when a black mask is provided). By having such a pigment content and film thickness, it is possible to obtain color-converted output light having a desired intensity.

  The color conversion layer 3 of the present invention can be formed by applying on the transparent substrate 1 a coating solution in which the above-described color conversion dye and matrix resin are dissolved in an organic solvent. Any coating method may be used as long as the surface (upper surface) of the color conversion layer 3 can be flattened. For example, the spin coating method, roll coating method, casting method, dip coating method, etc. It may be a method known in the art. By adopting such a forming method, the color conversion layer 3 is manufactured so as to have a relatively different thickness by changing the thickness of the color filter layer in a portion where the color filter layer exists. Is done. That is, if the color filter layer 2 is thick, the color conversion layer 3 is relatively thin, and if the color filter layer 2 is thin, the color conversion layer 3 is relatively thick.

Furthermore, in the method of the present embodiment, a gas barrier layer 4 that covers the color conversion layer 3 may be provided. The material that can be used to form the gas barrier layer 4 exhibits high transparency in the visible region (transmittance of 50% or more in the range of 400 to 700 nm), Tg of 100 ° C. or more, and surface hardness of 2H or more of pencil hardness. The material can be selected from materials that do not deteriorate the function of the color conversion layer 3 or the color conversion layer 4 below the material. Preferred materials for forming the gas barrier layer 4 _{comprises SiO x, SiN x, SiN x} O y, AlO x, TiO x, TaO x, an inorganic oxide or an inorganic nitride such as ZnO _x.

Furthermore, when the gas barrier layer 4 is provided in the method of the present invention, the gas barrier layer 4 may be a single layer or may have a multilayer structure using a plurality of separate materials. When the gas barrier layer 4 has a multilayer structure, the above-described inorganic oxide or inorganic nitride may be stacked. Alternatively, for the purpose of further improving the flatness of the surface of the gas barrier layer 4, the above-described inorganic oxide or inorganic nitride layer and an organic material layer may be laminated. Examples of the organic material that can be used include imide-modified silicone resins (see, for example, Patent Documents 8 to 10), acrylic, polyimide, or inorganic metal compounds dispersed in a silicone resin (TiO ₂ , Al ₂ O ₃ , SiO _2, etc.). , Patent Documents 11 and 12), epoxy-modified acrylate resins, UV curable resins such as acrylate monomers / oligomers / polymers containing reactive vinyl groups (see Patent Document 13), resist resins (Patent Documents 1 and 14-16) Reference), inorganic compounds (which may be formed by a sol-gel method, see Non-Patent Document 1 and Patent Document 17), photo-curing and / or thermosetting resins such as fluorine-based resins (see Patent Documents 16 and 18) )including.

  When forming the gas barrier layer 4 from the above materials, for example, a dry method (sputtering method, vapor deposition method, CVD method, etc.) and a wet method (spin coating method, roll coating method, casting method, dip coating method). Any method known in the art may be used. In addition, when the gas barrier layer 4 is provided, sufficient barrier properties against gas (oxygen, water vapor, organic solvent vapor, etc.) are achieved in order to minimize the viewing angle dependency (change in hue due to change in observation angle). As much as possible, it is preferable that the thickness of the gas barrier layer 4 is small.

  As described above, according to the present embodiment, a color filter with a color conversion function that provides three RGB colors necessary for full color display can be obtained. Therefore, a multicolor display can be formed by arranging a plurality of independently controllable light sources corresponding to the position of the color conversion layer. Here, since the matrix resin of the color conversion layer 3 is integrated as it is without being patterned, problems such as pattern shape reproducibility or deformation do not occur. Furthermore, since the color conversion layer 3 of the present embodiment is formed so as to cover a plurality of types of color filter layers 2 existing thereunder, the color filter layer 2 is protected from the influence of the surrounding environment (humidity, oxygen, etc.). It also has a function as a protective layer.

  Although the present embodiment has been described with respect to the case where the RGB color filter layer 2 is formed, it should be understood that other colors may be used. If desired, two or more, preferably 2 to 6 color filter layers may be formed.

  The color filter with a color conversion function of this embodiment is particularly useful in combination with a light source that can be independently controlled and can be arranged in a matrix with high definition. The light source is disposed on the color conversion layer 3 side. For example, it can be combined with a light valve with a liquid crystal shutter, an EL light emitting device, a plasma light emitting device, a light emitting diode (LED), etc., preferably an EL light emitting device, more preferably an organic EL light emitting device, most preferably blue to blue green light. It can be combined with an organic EL light emitting element that emits light. For example, the color filter with a color conversion function of the present embodiment and the organic EL light emitting element formed on another substrate may be bonded to produce a top emission type organic EL display. An organic EL light emitting element may be formed on a color filter with a color conversion function to form a bottom emission type organic EL display.

  The organic EL display of the second embodiment of the present invention is a combination of the color filter with a color conversion function of the first embodiment of the present invention and an organic EL light emitting element. FIG. 2 shows a top emission type organic EL display formed by bonding a color filter with a color conversion function and an organic EL light emitting element. An organic EL element including a planarizing film 12, a lower electrode 13, an organic EL layer 14, an upper electrode 15, and a passivation layer 16 is formed on a substrate 10 on which a TFT 11 is previously formed as a switching element. The lower electrode 13 is divided into a plurality of portions, each of which is a reflective electrode connected to the TFT 11 on a one-to-one basis, and the upper electrode 15 is a transparent electrode formed uniformly on the entire surface. Each layer forming the organic EL element can be formed using materials and methods known in the art.

  On the other hand, on the transparent substrate 1, blue, green and red color filter layers 2B, 2G and 2R and a color conversion layer 3 are formed. As optional components, a black mask 5 between and around each color filter layer, and a gas barrier layer 4 covering each color filter layer 2, the color conversion layer 3, and the black mask 5 are formed.

  Next, the organic EL element and the color conversion filter are aligned and bonded together while forming a filler layer 22 (which may be optionally provided) between them, and finally the peripheral portion is attached. An organic EL display is obtained by sealing using the outer peripheral sealing layer (adhesive) 21. Although FIG. 2 shows an active matrix drive type display, it goes without saying that a passive matrix drive type organic EL element may be used.

  FIG. 3 shows a bottom emission type organic EL display in which an organic EL light emitting element is directly formed on the color filter with a color conversion function of the present invention. The color filter with color conversion function in FIG. 3 includes blue, green and red color filter layers 2B, 2G and 2R formed on the transparent substrate 1, a color conversion layer 3, and a gas barrier layer 4 covering them. Including. As a matter of course, a black mask 5 may be provided between and around each color filter layer as an optional component. The organic EL light emitting device shown in FIG. 3 is a passive matrix drive type, and includes a first electrode 31 composed of a plurality of stripe-shaped partial electrodes extending in the first direction, an organic EL layer 32, and a plurality extending in the second direction. And a second electrode 33 made of a stripe-shaped partial electrode. Here, the first direction and the second direction are preferably crossed, more preferably orthogonal. In the configuration of FIG. 3, the first electrode 31 is a transparent electrode, and the second electrode 33 is a reflective electrode.

The aforementioned organic EL layers (14, 32) emit light in the near ultraviolet to visible region, preferably in the blue to blue-green region. The emitted light enters the color conversion filter layer, and the wavelength distribution is converted into visible light having a desired color. The organic EL layer (14, 32) 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. Specifically, those having the following layer structure are employed.
(1) Organic light emitting layer (2) Hole injection layer / organic light emitting layer (3) Organic light emitting layer / electron injection layer (4) Hole injection layer / organic light emitting layer / electron injection layer (5) Hole injection layer / Hole transport layer / organic light emitting layer / electron injection layer (6) Hole injection layer / hole transport layer / organic light emitting layer / electron transport layer / electron injection layer (in the above, the anode is an organic light emitting layer or a hole injection layer) And the cathode is connected to the organic light emitting layer or electron injection layer)

  Known materials are used as the material for each of the above layers. In order to obtain light emission from blue to blue-green, in the organic light emitting layer, for example, a fluorescent whitening agent such as benzothiazole, benzimidazole, and benzoxazole, a metal chelated oxonium compound, a styrylbenzene compound, Aromatic dimethylidin compounds are preferably used. In addition, a phthalocyanine compound such as copper phthalocyanine or a triphenylamine derivative such as m-MTDATA can be used as the hole injection layer, and a biphenylamine such as TPD or α-NPD can be used as the hole transport layer. Derivatives and the like can be used. On the other hand, an oxadiazole derivative such as PBD, a triazole derivative, a triazine derivative, or the like can be used for the electron transport layer, and an aluminum quinolinol complex or the like can be used for the electron injection layer. Furthermore, an alkali metal, an alkaline earth metal, an alloy containing them, an alkali metal fluoride, or the like may be used as the electron injection layer.

The transparent electrode can be formed by stacking conductive metal oxides such as SnO ₂ , In ₂ O ₃ , ITO, IZO, and ZnO: Al using a sputtering method. The transparent electrode preferably has a transmittance of 50% or more, more preferably 85% or more with respect to light having a wavelength of 400 to 800 nm. On the other hand, the reflective electrode can be formed by laminating a highly reflective metal, amorphous alloy, or microcrystalline alloy by vapor deposition or sputtering. High reflectivity metals include Al, Ag, Mo, W, Ni, Cr, and the like. High reflectivity amorphous alloys include NiP, NiB, CrP, CrB, and the like. The highly reflective microcrystalline alloy includes NiAl and the like. Alternatively, other alloys (for example, Mg / Ag alloy) containing the above-described highly reflective metal can be used.

  In the organic EL display having the above-described configuration, only the single color conversion layer 3 is formed, and blue to blue-green light emitted from the organic EL element as a light source (substantially does not include the spectrum in the red region). ) Can be converted into light that contains a large amount of spectrum in the red region, so that the cost can be reduced by simplifying the process. In addition, in blue or green sub-pixels, the color filter is made thicker to make the color conversion layer relatively thin, and the amount of hue change in the color conversion layer is reduced to be included in the backlight. The blue or green component can be used more effectively. On the other hand, in the red sub-pixel, by reducing the thickness of the color filter and relatively increasing the thickness of the color conversion layer, the amount of hue change in the color conversion layer is increased, and the spectrum of the red region is increased. More light is obtained. Therefore, it is possible to emit red light with higher luminance in the red subpixel.

Example 1
On a transparent substrate (Corning 1737 glass substrate), a black mask material (Fuji Film Arch: Color Mosaic CK-7000), a blue filter material (Fuji Film Arch: Color Mosaic CB-7001), a green filter material, and a red color Using a filter material (manufactured by Fuji Film Arch: Color Mosaic CR-7001), a color filter layer and a black mask were prepared by a photolithographic method.

  Here, the size of each subpixel is 300 μm × 100 μm; the gap between adjacent subpixels (that is, the region where the black mask is formed) is 30 μm in the vertical direction and 10 μm in the horizontal direction; blue, green and red subpixels Are arranged so as to form one pixel. In addition, 50 pixels in the vertical direction and 50 pixels in the horizontal direction are arranged to obtain a total of 2500 pixels. The film thickness of each color filter layer was 1.5 μm for red and 3 μm for blue and green. The film thickness of the black mask was 1 μm.

  Next, 0.05 g of coumarin 6 and 0.04 g of rhodamine B were added to 25 g of photoresist V259PAP5 (manufactured by Nippon Steel Chemical Co., Ltd.) to obtain a coating solution. This was applied to the upper surface of the color filter layer and the black mask to obtain a color conversion layer having a film thickness of 5 μm (film thickness on the upper surface of the black mask).

Next, a gas barrier layer made of a SiO ₂ film having a thickness of 0.5 μm was formed so as to cover the color conversion layer by sputtering, and a color filter with a color conversion function was obtained. An RF-planar magnetron type device was used as the sputtering device, SiO ₂ as the target, and Ar as the sputtering gas. The substrate temperature at the time of forming the SiO ₂ film was set to 80 ° C.

  A first electrode (reflective anode) made of Al having a thickness of 500 nm and ITO having a thickness of 100 nm was formed on a separate glass substrate by sputtering and photolithography. The first electrode had a stripe pattern extending in the vertical direction, and the width of each stripe was 105 μm and the pitch was 110 μm (the interval between adjacent stripes was 5 μm).

Next, the substrate on which the first electrode is formed is placed in a resistance heating vapor deposition apparatus, and at a vacuum chamber internal pressure of 10 ⁻⁴ Pa, CuPc with a film thickness of 100 nm as a hole injection layer and a film with a thickness of 20 nm as a hole transport layer. α-NPD, DPVBi with a thickness of 30 nm as a light emitting layer, and Alq with a thickness of 20 nm as an electron injection layer were stacked to form an organic EL layer.

  And the 2nd electrode which consists of Mg / Ag (mass ratio 10/1) with a film thickness of 10 nm and ITO with a film thickness of 10 nm was laminated | stacked on the organic EL layer using the mask. The second electrode had a stripe pattern extending in the lateral direction, and the width of each stripe was set to 300 μm, and the pitch was arranged to be 330 μm (the interval between adjacent stripes was 30 μm).

Finally, a passivation layer made of SiO ₂ having a thickness of 500 nm was formed so as to cover the structure below the second electrode, thereby obtaining an organic EL light emitting device.

Next, the color filter with a color conversion function and the organic EL light emitting element were carried into a glove box controlled to have a moisture concentration of 1 ppm and an oxygen concentration of 1 ppm. Then, a UV curable adhesive (trade name 30Y-437, manufactured by ThreeBond Co., Ltd.) in which beads having a diameter of 6 μm are dispersed on the outer periphery of the transparent substrate of the color filter with a color conversion function using a dispenser robot. It was applied as a stop layer. While performing alignment, the color fill with color conversion function and the organic EL light emitting element were adhered to form an assembly. Then, 100 mW / cm < ² > ultraviolet-ray was irradiated over 30 second, the outer periphery sealing layer was hardened, and the organic EL display was obtained.

  The light emission characteristics of the organic EL display produced as described above were measured. Specifically, the chromaticity value when all the pixels are lit (W), and the chromaticity value and the luminance ratio (all pixels) when only the sub-pixels corresponding to each color are lit (R, G, B) The relative value with respect to 100 when the was turned on was measured. The results are shown in Table 1.

It is the schematic which shows the manufacturing method of the filter with a color conversion function of the 1st Embodiment of this invention. It is a schematic sectional drawing which shows an example of the organic electroluminescent display formed using the filter with a color conversion function manufactured by the method of this invention. It is a schematic sectional drawing which shows another example of the organic electroluminescent display formed using the filter with a color conversion function manufactured by the method of this invention.

Explanation of symbols

1 Transparent substrate 2 (R, G, B) Color filter layer (red, green, blue)
3 Color conversion layer 4 Gas barrier layer 5 Black mask 10 Substrate 11 TFT
DESCRIPTION OF SYMBOLS 12 Planarization film | membrane 13, 31 1st electrode 14, 32 Organic EL layer 15, 33 2nd electrode 16 Passivation layer 21 Periphery sealing layer 22 Filler layer

Claims (12)

A transparent substrate;
A plurality of color filter layers formed on a transparent substrate;
A color conversion layer that includes at least one color conversion dye and is integrally formed to cover the plurality of types of color filter layers and has a flat surface, wherein the at least one color conversion dye is a part of incident light. A color filter having a color conversion function, wherein the color filter layer emits light in a wavelength range different from the absorbed wavelength range, and a part of the plurality of types of color filter layers is thicker than the other color filter layers .   The color filter with a color conversion function according to claim 1, wherein the color conversion layer also functions as a protective layer for the plurality of types of color filters.   The incident light to the color conversion layer is blue or blue-green light, and the at least one color conversion dye radiates light including a spectrum in a red region. Color filter.   The plurality of types of color filter layers are composed of a red color filter layer, a green color filter layer, and a blue color filter layer, and the green color filter layer and the blue color filter layer are thicker than the red color filter layer. The color filter with a color conversion function according to claim 3.   2. The color filter with a color conversion function according to claim 1, wherein in the color conversion layer, the at least one color conversion pigment is dispersed in a matrix resin.   The color filter with a color conversion function according to claim 1, further comprising a gas barrier layer covering the color conversion layer. A transparent substrate;
A plurality of color filter layers formed on a transparent substrate;
A color conversion layer comprising at least one color conversion dye, integrally formed to cover the plurality of types of color filter layers, and having a flat surface;
A transparent electrode;
An organic EL layer including at least an organic light emitting layer;
The at least one color conversion dye absorbs a part of the wavelength range of the incident light, emits light in a wavelength range different from the absorbed wavelength range, and includes one of the plurality of types of color filter layers. An organic EL display characterized in that the portion is thicker than other color filter layers.   The organic EL display according to claim 7, wherein the color conversion layer also functions as a protective layer of the at least one color filter.   8. The organic EL display according to claim 7, wherein the organic light emitting layer emits blue or blue-green light, and the at least one color conversion dye emits light including a spectrum in a red region.   The plurality of types of color filter layers are composed of a red color filter layer, a green color filter layer, and a blue color filter layer, and the green color filter layer and the blue color filter layer are thicker than the red color filter layer. The organic EL display according to claim 9.   8. The organic EL display according to claim 7, wherein in the color conversion layer, the at least one color conversion dye is dispersed in a matrix resin.   The organic EL display according to claim 7, further comprising a gas barrier layer covering the color conversion layer.

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