JP5087837B2 - Color filter for organic electroluminescence device - Google Patents

Description

  The present invention relates to a color filter for an organic electroluminescence element used in, for example, an organic electroluminescence display device.

  An organic electroluminescence (hereinafter, abbreviated as “organic EL”) element has high luminous efficiency such as high luminance emission even when the applied voltage is less than 10 V, and can emit light with a simple element structure. Therefore, application to image display devices is expected, and research is actively conducted. In particular, the organic EL element has high visibility due to self-coloring, is different from a liquid crystal display in that it is an all-solid-state display, has excellent impact resistance, is less affected by temperature changes, and has a large viewing angle. In recent years, it has been put to practical use as a light emitting element in an image display device.

In order to obtain an organic EL display device capable of color display using an organic EL element, it is known to use a color filter. Generally, a color filter has a black matrix and red, green, and blue colored layers formed on a substrate, and a flattening layer is formed to flatten the level difference due to the pattern of the colored layer and the unevenness of the colored layer surface. It has been done.
However, when the level difference due to the pattern of the colored layer is large, it is necessary to make the planarizing layer thicker, and when the planarized layer is formed on the colored layer, there is a problem that the transmittance is lowered. .

  In addition, after forming the blue and green colored layers, the red colored layer composition is applied to form a red colored layer, and the gap between the blue and green colored layers is formed with the red colored layer composition. A method of flattening by filling and then polishing the surface of the colored layer has been proposed (see, for example, Patent Document 1). According to this method, it is not necessary to provide a flattening layer, and even if a flattening layer is provided, a relatively thin layer is sufficient, so that a decrease in transmittance can be prevented. However, since a red colored region is also provided in the gap between the blue and green colored layers, color mixing may occur.

JP 2005-173092 A

  The present invention has been made in view of the above problems, and a main object of the present invention is to provide a color filter for an organic EL element having high transparency and an organic EL display device having high luminance.

  In order to achieve the above object, the present invention has an organic EL device comprising a substrate, a colored layer formed in a pattern on the substrate, and a planarized portion formed between the colored layers. A color filter is provided.

  According to the present invention, by providing a flattened portion between the colored layers, a step due to the patterned colored layer can be filled, so there is no need to provide a flattened layer on the colored layer as in the prior art, and transparency is improved. It is possible to increase. Therefore, by using the color filter for organic EL elements of the present invention, an organic EL display device having high luminance and excellent color display characteristics can be obtained. Moreover, since the surface is planarized by the colored layer and the planarization part, when the color filter for organic EL elements of this invention is used for an organic EL display apparatus, the short circuit between electrodes can be prevented.

  In the said invention, the said planarization part may have light-shielding property. This is because the contrast can be improved.

  In the present invention, the colored layer is preferably a film in which a colorant is dispersed in ultrafine particles, and the flattened portion is preferably a film formed of ultrafine particles. In a film in which a colorant is dispersed in ultrafine particles, since the ultrafine particles function as a binder, it is not necessary to use a resin as a binder as in the prior art, and a colored layer having excellent low degassing properties can be obtained. Similarly, a film formed of ultrafine particles is also excellent in low outgassing properties. Therefore, when the color filter for organic EL elements of the present invention is used in an organic EL display device, the occurrence of dark spots can be suppressed and good image display can be achieved. In addition, since the generation of dark spots can be suppressed, it is not necessary to provide a thick barrier layer as in the prior art, and cost reduction and yield improvement can be achieved. Furthermore, a colored layer is formed by applying and baking a coating solution for forming a colored layer composed of an ultrafine particle dispersion in which ultrafine particles and a colorant are dispersed in a solvent, and ultrafine particle dispersion in which ultrafine particles are dispersed in a solvent. When the flattened part is formed by applying and firing a flattened part-forming coating liquid made of a liquid, the sintering temperature can be lowered by the size effect peculiar to ultrafine particles, and the heat resistance temperature of the colored layer The following firing is possible.

  In this case, the sintering temperature of the ultrafine particles is preferably 350 ° C. or lower. This is because by using ultrafine particles having a sintering temperature in the above range, as described above, when the colored layer and the flattened portion are formed, firing can be performed at a lower temperature.

In this case, the ultrafine particles are preferably at least one ultrafine particle selected from the group consisting of indium oxide, silicon oxide, silicon nitride, and silicon oxynitride. This is because by using these ultrafine particles, a colored layer and a flattened portion having high transparency and insulation can be formed.
Furthermore, it is also preferable that the ultrafine particles are at least one kind of ultrafine particles selected from the group consisting of indium, alkali metal, and alkaline earth metal whose surface is oxidized. This is because indium, alkali metal, and alkaline earth metal are highly oxidizable, so that oxidation is promoted even by firing at a relatively low temperature.

  The average particle size of the ultrafine particles is preferably in the range of 0.5 nm to 100 nm. This is because production of ultrafine particles having an average particle size that is too small is difficult, and if the average particle size of the ultrafine particles is too large, a decrease in the sintering temperature due to the size effect of the ultrafine particles cannot be expected.

  Furthermore, the present invention is a method for producing a color filter for an organic EL element, comprising a substrate, a colored layer formed in a pattern on the substrate, and a flattened portion formed between the colored layers, A method for producing a color filter for an organic EL element, comprising: a surface treatment step of polishing the surfaces of the colored layer and the planarized portion after forming the colored layer and the planarized portion on the surface.

  According to the present invention, the surface of the colored layer and the flattened part can be easily flattened by polishing, and when the flattened part is formed on the colored layer, Since the flattened portion can be removed, it is possible to obtain a color filter for an organic EL element that is unlikely to cause a short circuit between the electrodes and has high transparency.

  In the method for producing a color filter for an organic EL device of the present invention, a coating solution for forming a colored layer comprising an ultrafine particle dispersion in which ultrafine particles and a colorant are dispersed in a solvent is applied on the substrate, followed by baking. Applying a coating liquid for forming a flattened portion made of an ultrafine particle dispersion in which ultrafine particles are dispersed in a solvent on the above-mentioned substrate; It is preferable to include a flattening portion forming step for forming the flattening portion. In the colored layer forming step, since a resin is not used as a binder in the colored layer forming coating solution, a colored layer having excellent low degassing properties can be formed. In the flattening portion forming step, similarly, a flattening portion having excellent low degassing properties can be formed. Therefore, it is possible to manufacture a color filter for an organic EL element that hardly generates dark spots. Furthermore, because of the size effect peculiar to ultrafine particles, it can be fired at a temperature lower than the normal sintering temperature, so that the firing can be performed at a temperature lower than the heat resistance temperature of the colored layer.

  In this case, the boiling point of the solvent is preferably 120 ° C. or higher. If the boiling point of the solvent is relatively high, it is possible to prevent the solvent from evaporating at the time of drying after the application of the ultrafine particle dispersion, and this causes the ultrafine particles to aggregate and impair the flatness of the colored layer and the flattened portion. This is because it can be avoided.

  Further, in the colored layer forming step and the flattening portion forming step, baking may be performed in an atmosphere in which the ultrafine particles are not oxidized, and then baking in an oxidizing atmosphere. This is because the ultrafine particles can be sufficiently sintered to form a dense colored layer and a flattened portion.

  Furthermore, the present invention provides a color filter for an organic EL element described above, a transparent electrode layer formed on the color filter for organic EL element, an organic EL layer formed on the transparent electrode layer and including at least a light emitting layer, And an organic EL display device comprising a back electrode layer formed on the organic EL layer.

  Since the organic EL display device of the present invention uses the above-described color filter for organic EL elements, it has high luminance and excellent color display characteristics, and can display a good image without defects such as dark spots. Moreover, since it is not necessary to provide a thick barrier layer as in the prior art, an inexpensive organic EL display device can be provided.

  According to the present invention, it is possible to obtain a color filter for organic EL elements having a flat surface and high transparency, and it is possible to provide an organic EL display device having high luminance and excellent color display characteristics.

  Hereinafter, the color filter for organic EL elements of the present invention, the manufacturing method thereof, and the organic EL display device will be described in detail.

A. First, the color filter for organic EL elements of the present invention will be described.
The color filter for organic EL elements of the present invention is characterized by having a substrate, a colored layer formed in a pattern on the substrate, and a flattened portion formed between the colored layers.

The color filter for organic EL elements of the present invention will be described with reference to the drawings.
FIG. 1 is a schematic cross-sectional view showing an example of a color filter for an organic EL element of the present invention. As shown in FIG. 1, the organic EL element color filter 10 has a patterned colored layer 2 formed on a substrate 1 and a planarized portion 3 formed between the patterned colored layers 2. .
In the present invention, that the flattened portion is formed between the colored layers means that there is no flattened portion on the colored layer. Moreover, that the planarization part does not exist on a colored layer means that the thickness of the planarization part on a colored layer is 10 nm or less.

An example of an organic EL display device using the color filter for organic EL elements of the present invention is shown in FIG. In the organic EL display device 20 illustrated in FIG. 2, the transparent electrode layer 21, the organic EL layer 22, and the back electrode layer 23 are formed on the colored layer 2 and the flattening portion 3 of the color filter 10 for the organic EL element. ing. An insulating layer 23 is formed between the organic EL layers 22, and a partition wall 24 is formed on the insulating layer 23.
In the color filter for organic EL elements of the present invention, since there is no flattened portion on the colored layer, light emitted from the organic EL layer passes through the colored layer without passing through the flattened portion. Therefore, it is possible to prevent the transmittance from being lowered due to the light emission from the organic EL layer being absorbed by the planarizing portion. Therefore, the organic EL display device using the color filter for organic EL elements of the present invention can display a high-quality image with high luminance.
In addition, since the surface is flattened by the colored layer and the flattened portion, a short circuit between the electrodes can be prevented.
Hereinafter, each structure of the color filter for organic EL elements is demonstrated.

1. Flattening portion The flattening portion used in the present invention is formed between the colored layers formed in a pattern on the substrate, and is provided for the purpose of filling a step due to the patterned colored layer.

The thickness of the flattened portion is preferably about the same as the thickness of the colored layer. In particular, as illustrated in FIG. 1, the difference between the thickness d1 of the flattened portion 3 and the thickness d2 of the colored layer 2 is 500 nm or less. It is preferable. Further, when a color conversion layer is formed on the colored layer as will be described later, the thickness d1 of the flattening portion 3, the thickness d2 of the colored layer 2, and the color conversion layer 5 are exemplified as shown in FIG. The difference from the combined thickness d3 is preferably 500 nm or less. Thereby, the level | step difference by a pattern-like colored layer and a color conversion layer can be planarized, and when the color filter for organic EL elements of this invention is used for an organic EL display apparatus, the short circuit between electrodes can be prevented. Because.
The thickness of the flattened portion is appropriately adjusted depending on the thickness of the colored layer or the color conversion layer, but can be set within a range of 500 nm to 5 μm, for example, when the colored layer is formed. Preferably, it exists in the range of 1 micrometer-3 micrometers. Moreover, when the colored layer and the color conversion layer are formed, it can set in the range of 1 micrometer-55 micrometers, for example, Preferably it exists in the range of 2 micrometers-13 micrometers.

  Further, the formation position of the flattened portion is not particularly limited as long as it is a region where the colored layer is not formed.

  The flattened portion used in the present invention may have transparency or may have light shielding properties. When the flattened portion has transparency, the luminance can be increased when an organic EL display device is formed using the color filter for organic EL elements of the present invention. Moreover, when a planarization part has light-shielding property, when it is set as an organic EL display apparatus using the color filter for organic EL elements of this invention, a contrast can be improved. In the following, description will be made separately on a planarizing portion having transparency and a planarizing portion having light shielding properties.

(1) Permeability flattening part The material for forming the permeation flattening part is not particularly limited as long as it can fill a step due to a patterned colored layer. Can be mentioned. The resin preferably has a visible light transmittance of 50% or more. For example, polymethyl methacrylate, polyacrylate, polycarbonate, polyvinyl alcohol, polyvinyl pyrrolidone, hydroxyethyl cellulose, carboxymethyl cellulose, polyvinyl chloride resin, melamine resin, phenol resin Alkyd resin, epoxy resin, polyurethane resin, polyester resin, maleic acid resin, polyamide resin and the like. In addition, a photosensitive resin can be used as the resin. For example, an ionizing radiation curable resin (electron beam curable resin or ultraviolet ray) having a reactive vinyl group such as acrylate, methacrylate, polyvinyl cinnamate, and cyclic rubber. Curable resin).

Further, the planarizing portion having permeability may be a film formed of ultrafine particles. Here, the “film formed of ultrafine particles” refers to a film obtained by applying and baking an ultrafine particle dispersion in which ultrafine particles are dispersed in a solvent. Since the film formed of ultrafine particles does not contain an organic material, degassing does not occur even when exposed to high temperatures. Therefore, when the color filter for organic EL elements of the present invention is used in an organic EL display device, it is possible to prevent the occurrence of dark spots and to display a good image. Further, as will be described later, since the average particle size of the ultrafine particles is smaller than the wavelength in the visible light region, light scattering by the ultrafine particles can be suppressed, and a flattened portion having high transparency can be obtained.
In the present invention, it is preferable that the flattened portion is a film formed of ultrafine particles because of the advantages described above.

  In the present invention, “ultrafine particles” are fine particles made of an inorganic material having an average particle diameter of 100 nm or less, and are fine particles that are individually and uniformly dispersed in a dispersion medium. For such ultrafine particles, reference can be made to JP-A Nos. 2002-121437 and 2005-81501.

  The ultrafine particles used in the present invention only need to have transparency, and preferably have insulating properties. This is because in general, the planarizing portion is required to have insulation. Examples of such ultrafine particles include inorganic oxides, inorganic nitrides, and inorganic oxynitride ultrafine particles. Specifically, inorganic oxides include indium oxide, silicon oxide, aluminum oxide, titanium oxide, tantalum oxide, zinc oxide, magnesium oxide, tin oxide, yttrium oxide, germanium oxide, calcium oxide, boron oxide, strontium oxide, and oxide. Examples include barium, lead oxide, zirconium oxide, sodium oxide, lithium oxide, and potassium oxide. Examples of the inorganic nitride include silicon nitride, aluminum nitride, titanium nitride, and silicon carbonitride. Examples of inorganic oxynitrides include silicon oxynitride. These may be used alone or in combination of two or more. Further, a mixed system of inorganic oxide and inorganic nitride may be used.

  Among these, at least one ultrafine particle selected from the group consisting of indium oxide, silicon oxide, silicon nitride, and silicon oxynitride is preferably used. This is because by using these ultrafine particles, a flattened portion having good transparency and insulation can be obtained. In addition, when forming a flattened part by applying and baking a coating liquid for forming a flattened part made of an ultrafine particle dispersion in which ultrafine particles are dispersed in a solvent, ultrafine particles of indium oxide are used. This is because the sintering temperature can be lowered. Furthermore, when ultrafine particles of silicon oxide, silicon nitride, and silicon oxynitride are used, adhesion with a substrate or the like can be improved.

  Moreover, as the ultrafine particles, ultrafine particles of metal whose surface is oxidized can also be used. Specifically, In, Al, Ti, Ta, Zn, Sn, Y, Ge, Pb, Zr, alkali metals (Li, Na, K), alkaline earth metals (Mg, Ca, Sr, Ba), etc. Examples include ultrafine particles. Among these, at least one kind of ultrafine particles selected from the group consisting of In (indium), alkali metals, and alkaline earth metals is preferably used. This is because indium, alkali metal, and alkaline earth metal are highly oxidizable, so that oxidation is promoted even by firing at a relatively low temperature. Since the ultrafine metal particles whose surface is oxidized have an insulating property, they can be used for the planarization portion.

The ultrafine particles preferably have a sintering temperature of 350 ° C. or lower. By using ultrafine particles having a sintering temperature in the above range, the firing temperature at the time of forming the flattened portion can be lowered. In addition, the lower the sintering temperature of the ultrafine particles, the better, but the lower limit is usually about 180 ° C. Some metals have a melting point of less than 180 ° C., and the sintering temperature of ultrafine particles containing such a metal is usually less than 180 ° C., but a metal having a melting point of less than 180 ° C. is very oxidized. The lower limit of the sintering temperature is within the above range because it is easy to do and leads to an increase in the sintering temperature.
Here, sintering refers to a phenomenon in which when an aggregate of ultrafine particles is heated to a high temperature, it is baked and solidified into a dense polycrystalline body. The ultrafine particles are in a thermodynamically non-equilibrium state, and mass transfer occurs in the direction of decreasing the surface area. As a result, bonding occurs between the particles and the particles become dense. That is, the driving force for sintering is a force that attempts to minimize the surface energy of the system. The sintering temperature is a temperature at which the ultrafine particles become dense and baked when the aggregate of ultrafine particles is heated at a temperature below the melting point of the ultrafine particles.
The sintering temperature can be measured by differential thermal analysis (DTA). In DTA, a temperature difference between a sample and a reference material (generally alumina) can be measured to obtain a transition temperature, and a temperature difference (sample) generated when heat is applied to the sample and the reference material. Thus, the sintering temperature can be determined. That is, when the sample and the reference material are heated in the same atmosphere, the temperature of the reference material is increased, whereas when the sample temperature is not increased, heat is applied to the sintering of the ultrafine particles. It can be said that an endothermic phenomenon has occurred. Therefore, the temperature at which the endothermic phenomenon is observed, that is, the endothermic start temperature in the DTA curve is defined as the sintering temperature in the present invention.
Note that a TG-DTA apparatus (TG 8120) manufactured by Rigaku is used for the measurement of the sintering temperature.

  The ultrafine particles preferably contain a metal having a melting point of about 700 ° C. or lower. This is because if the melting point of a single metal is relatively low as in the above range, the sintering temperature of the ultrafine particles is expected to be relatively low. Examples of such metal include Al (660 ° C.), In (156.4 ° C.), Mg (651 ° C.), Sn (231.85 ° C.), Zn (419.43 ° C.), Pb (327.5 ° C.). ), Na (97.5 ° C.), Li (186 ° C.), K (62.3 ° C.) and the like. The numbers in parentheses are melting points.

Furthermore, the average particle diameter of the ultrafine particles is not limited as long as the sintering temperature can be lowered. Specifically, it is preferably in the range of 0.5 nm to 100 nm, more preferably 1 nm to 50 nm, and still more preferably. It is in the range of 1 nm to 10 nm. If the average particle size is too small, it is difficult to produce. On the other hand, if the average particle size is too large, a decrease in sintering temperature due to the size effect unique to ultrafine particles cannot be expected.
Here, the average particle diameter of the ultrafine particles can be confirmed by a scanning electron microscope (SEM) observation photograph (high magnification).

  The method for producing the ultrafine particles is not particularly limited, and for example, a gas evaporation method, a wet reduction method, a thermal reduction method by spraying an organometallic compound in a high temperature atmosphere, or the like is used.

  Examples of the method for forming the flattened portion using a resin include a spin coating method, a roll coating method, a bar coating method, a casting method, and an ink jet method.

  When a film formed of ultrafine particles is formed as the flattening portion, the film is flattened by applying and baking a flattening portion forming coating solution made of an ultrafine particle dispersion in which ultrafine particles are dispersed in a solvent. It is preferable to form a chemical conversion part. That is, the flattened part is preferably a coating film formed of ultrafine particles. By forming the flattened portion by such a method, the sintering temperature can be lowered compared with the normal sintering temperature due to the size effect peculiar to the ultrafine particles, and the temperature is lower than the heat resistance temperature of a general colored layer. Can be fired. Therefore, the choice of the colorant used for the colored layer is widened, and for example, an optimal colorant can be selected in order to obtain good color characteristics. Note that a method for forming such a flattened portion is described in “B. Method for manufacturing color filter for organic EL element” which will be described later, and thus the description thereof is omitted here.

(2) Flattening part having light-shielding property The planarizing part having light-shielding property may be the light-shielding part 3a as illustrated in FIG. 4, and the light-shielding part 3a and the transmissive part 3b as illustrated in FIG. And may be laminated.

Examples of the material for forming the light shielding part include a resin composition containing a black colorant, and metal materials such as chromium, chromium oxide, and chromium nitride.
The light shielding part may be a film in which a black colorant is dispersed in ultrafine particles. The film in which the black colorant is dispersed in the ultrafine particles contains almost no organic material, so that it is difficult for outgassing to occur even when exposed to high temperatures, and the generation of dark spots can be prevented. In the present invention, the film in which the black colorant is dispersed in the ultrafine particles is included in the film formed of the ultrafine particles.
Among these, a light-shielding part using a metal material and a light-shielding part that is a film in which a black colorant is dispersed in ultrafine particles have an advantage of excellent low degassing properties. On the other hand, the light shielding part using the resin composition containing the black colorant can be subjected to sufficient heat treatment, and the degassing component can be removed when the light shielding part is formed. In particular, from the viewpoint of low degassing property and improvement in contrast, the light shielding part is preferably a film in which a black colorant is dispersed in ultrafine particles.

  As the black colorant used in the present invention, a pigment can be used, which may be an organic pigment or an inorganic pigment. Here, even when an organic pigment is used, the amount of the black colorant contained in the light-shielding part is very small compared to the content of the ultrafine particles. It is thought that it does not become a big cause of.

Examples of the black colorant include titanium pigments such as titanium nitride, titanium oxide, and titanium oxynitride, and carbon black. Of these, titanium pigments are preferably used because of their high volume resistivity.
Content of the said black coloring agent can be about 5 to 50 weight% in a light-shielding part. This is because if the content of the black colorant is less than the above range, the light shielding property is lowered, and if the content of the black colorant is more than the above range, the dispersibility of the black colorant may be deteriorated.

In addition, as the black colorant, at least two kinds selected from the group consisting of a blue colorant, a red colorant, and a yellow colorant can be mixed and used. As the blue colorant, the red colorant, and the yellow colorant, an organic pigment or an inorganic pigment can be used.
Organic pigments are compounds classified as Pigments in the Color Index (CI: published by The Society of Dyers and Colorists) from the viewpoint of spectral characteristics and insulating properties, that is, the following Color Index (CI ) Those numbered are preferably used.
Examples of red colorants include CI Pigment Red 1, CI Pigment Red 2, CI Pigment Red 3, CI Pigment Red 9, CI Pigment Red 97, CI Pigment Red 122, CI Pigment Red 123, CI Pigment Red 144, and CI Pigment Red. 149, CI Pigment Red 166, CI Pigment Red 177, CI Pigment Red 180, CI Pigment Red 192, CI Pigment Red 215, CI Pigment Red 216, CI Pigment Red 224, CI Pigment Red 254, and the like.
Examples of yellow coloring agents include CI Pigment Yellow 1, CI Pigment Yellow 3, CI Pigment Yellow 12, CI Pigment Yellow 13, CI Pigment Yellow 20, CI Pigment Yellow 24, CI Pigment Yellow 83, CI Pigment Yellow 86, CI Pigment Yellow 93, CI Pigment Yellow 94, CI Pigment Yellow 109, CI Pigment Yellow 110, CI Pigment Yellow 117, CI Pigment Yellow 125, CI Pigment Yellow 137, CI Pigment Yellow 138, CI Pigment Yellow 139, CI Pigment Yellow 147, CI Pigment Yellow 148, CI pigment yellow 150, CI pigment yellow 153, CI pigment yellow 154, CI pigment yellow 166, CI pigment yellow 173, CI pigment yellow 180, CI pigment yellow 185 and the like.
Examples of blue colorings include CI Pigment Blue 15, CI Pigment Blue 15: 3, CI Pigment Blue 15: 4, CI Pigment Blue 15: 6, CI Pigment Blue 21, CI Pigment Blue 22, CI Pigment Blue 60, CI Pigment Blue pigments such as Blue 64 can be listed.
As specific examples of inorganic pigments, red iron oxide (III), cadmium red, etc. as red colorants, yellow lead, yellow zinc, etc. as yellow colorants, ultramarine blue, bitumen, etc. as blue colorants Can do.
The total content of the red colorant, the yellow colorant, and the blue colorant varies depending on whether the colorant is an organic pigment or an inorganic pigment, but can be about 5 to 50% by weight in the light shielding portion. This is because if the content of these colorants is less than the above range, the light shielding property may be lowered. On the other hand, if the content is more than the above range, the coating characteristics at the time of forming the light-shielding part may deteriorate, the difference in light-shielding property may occur due to the lower dispersibility of the colorant, and the flatness may be poor. Because there is a possibility of becoming.

  In addition, since it is the same as that of what was described in the term of the said planarization part which has the transparency about ultrafine particles, description here is abbreviate | omitted.

As a method for forming the light shielding portion, for example, when a resin composition containing a black colorant is used, a photolithography method or the like can be used. In the case of using a metal material, for example, a method of forming a thin film by a sputtering method, a vacuum deposition method, or the like, and forming it in a pattern using a photolithography method can be given. Moreover, an electroless plating method, a printing method, etc. can also be used.
Further, when forming a film in which the black colorant is dispersed in the ultrafine particles as the light shielding part, a coating solution for forming the light shielding part comprising the ultrafine particle dispersion liquid in which the ultrafine particles and the black colorant are dispersed in the solvent is used. It is preferable to form the light shielding part by coating and baking. That is, the light shielding part is preferably a coating film in which a black colorant is dispersed in ultrafine particles. By forming the light-shielding portion by such a method, the sintering temperature can be lowered to the heat resistance temperature of the colored layer or less due to the size effect unique to the ultrafine particles. In addition, since the formation method of such a light-shielding part is described in the section of “B. Manufacturing method of color filter for organic EL element” described later, description thereof is omitted here.

  In the case where the light-shielding flattening portion is a laminate of a light-shielding portion and a transmissive portion, the transmissive portion is the same as the flattening portion having the light-transmitting property, and the description thereof is omitted here.

2. Colored layer The colored layer used in the present invention is formed in a pattern on the substrate, and emits from the light emitting layer of the organic EL display device when the organic EL display device is formed using the color filter for organic EL elements of the present invention. It is a layer that changes the color tone of the emitted light. As illustrated in FIG. 1, the colored layer 2 generally includes a red colored pattern 2R, a green colored pattern 2G, and a blue colored pattern 2B. By forming the colored layer, when the color filter for organic EL elements of the present invention is used in an organic EL display device, it is possible to achieve high-purity color development and high color reproducibility.

As a material for forming the colored layer, pigments and binder resins that can be generally used for color filters can be used.
Examples of the pigment used in the red coloring pattern include perylene pigments, lake pigments, azo pigments, quinacridone pigments, anthraquinone pigments, anthracene pigments, and isoindoline pigments. These pigments may be used alone or in combination of two or more.
Examples of the pigment used in the green coloring pattern include halogen multi-substituted phthalocyanine pigments, halogen multi-substituted copper phthalocyanine pigments, triphenylmethane basic dyes, isoindoline pigments, and isoindolinone pigments. . These pigments may be used alone or in combination of two or more.
Examples of the pigment used in the blue coloring pattern include copper phthalocyanine pigments, indanthrene pigments, indophenol pigments, cyanine pigments, dioxazine pigments and the like. These pigments may be used alone or in combination of two or more.
The colorant is usually contained in each colored pattern within a range of 5 to 50% by weight.

  The binder resin used for the colored layer is preferably a resin having a visible light transmittance of 50% or more. In addition, about resin, since it is the same as that of what was described in the term of the said planarization part, description here is abbreviate | omitted.

In the present invention, the colored layer may be a film in which a colorant is dispersed in ultrafine particles. Since a film in which a colorant is dispersed in ultrafine particles contains almost no organic material, degassing hardly occurs even when exposed to high temperatures, and generation of dark spots can be prevented. Further, since the average particle diameter of the ultrafine particles is smaller than the wavelength in the visible light region, light scattering by the ultrafine particles can be suppressed, and a colored layer having high transparency and excellent color characteristics can be obtained. Further, when the thickness of the colored layer is relatively thin, concentration quenching is likely to occur due to aggregation of the colorant. However, in the film in which the colorant is dispersed in the ultrafine particles, the dispersibility of the ultrafine particles is good, Then, since the colorant can be dispersed without agglomerating with the ultrafine particles, the thickness of the colored layer can be reduced without deteriorating the color characteristics.
Furthermore, when the colored layer is a film in which a colorant is dispersed in ultrafine particles, and the flattened portion is a film formed of ultrafine particles, it is possible to suppress the occurrence of dark spots. There is no need to provide such a thick barrier layer, and the cost can be reduced and the yield can be improved.
In the present invention, since the above-described advantages are obtained, the colored layer is preferably a film in which a colorant is dispersed in ultrafine particles.

Examples of the colorant used in this case include pigments, which may be organic pigments or inorganic pigments. Here, even when an organic pigment is used, it is considered that the amount of the colorant contained in the colored layer is smaller than the content of the ultrafine particles, so that it does not cause a large dark spot. As the colorant, those described above can be used.
Moreover, although content of a coloring agent changes with whether it is an organic pigment or an inorganic pigment, it is normally made into the range of 5 to 50 weight% normally in each coloring pattern. This is because if the content of the colorant is less than the above range, sufficient color correction may not be performed. Further, if the content of the colorant is more than the above range, the dispersibility of the colorant is deteriorated, the coating characteristics at the time of forming the colored layer are deteriorated, or the concentration difference is partially due to the decrease in the dispersibility of the colorant. This is because there is a possibility of the occurrence of the occurrence of the problem and the flatness may be deteriorated.

  In addition, since it is the same as that of what was described in the term of the said planarization part about ultrafine particles, description here is abbreviate | omitted.

  The thickness of the colored layer is not particularly limited as long as it is a thickness capable of correcting the color of light. Specifically, it can be set within a range of 500 nm to 5 μm, and preferably within a range of 1 μm to 3 μm. Is within. This is because if the thickness of the colored layer is too thick, the permeability may be lowered or peeling from the substrate or the like may occur. Furthermore, if the thickness of the colored layer is too thick, a step due to the patterned colored layer becomes large, and flattening by the flattening portion may be difficult. On the other hand, if the thickness of the colored layer is too thin, there is a possibility that sufficient color correction cannot be performed.

As a method for forming a colored layer using a pigment or a binder resin, a general method for forming a color filter, for example, a photolithography method, an inkjet method, a printing method, or the like can be used.
In addition, when forming a colored layer, which is a film in which a colorant is dispersed in ultrafine particles, a coating solution for forming a colored layer comprising an ultrafine particle and an ultrafine particle dispersion in which a colorant is dispersed in a solvent is applied. Then, it is preferable to form a colored layer by firing. That is, the colored layer is preferably a coating film in which a colorant is dispersed in ultrafine particles. By forming the colored layer by such a method, the sintering temperature can be lowered below the heat resistant temperature of the colored layer due to the size effect unique to the ultrafine particles. Therefore, it is possible to obtain a colored layer having excellent low degassing properties without narrowing the choice of the colorant used for the colored layer. In addition, since the formation method of such a colored layer is described in the section of “B. Manufacturing method of color filter for organic EL element” described later, description thereof is omitted here.

3. Color Conversion Layer In the present invention, for example, as shown in FIG. 3, a color conversion layer 5 may be formed on the colored layer 2. The color conversion layer is a layer that absorbs light emitted from the light emitting layer and emits fluorescence in the visible light region when an organic EL display device is formed using the color filter for organic EL elements of the present invention. There is no particular limitation as long as the light can be red, green, or blue.

  For example, as shown in FIG. 3, the color conversion layer may be composed of color conversion patterns 5R, 5G, and 5B that emit red, green, and blue fluorescence. When the blue light emitting layer is used, a red conversion pattern for converting blue light emission into red and a green conversion pattern for converting blue light emission into green may be formed. In this case, a transparent pattern may be formed instead of the blue conversion pattern, or the blue conversion pattern may not be formed. Furthermore, when a white light emitting layer is used, and the white light emission is mainly composed of red and blue light, the luminance of green is lower than that of red and blue, so the blue light emission is changed to green. It suffices if a green conversion pattern to be converted is formed. In this case, a transparent pattern may be formed instead of the red conversion pattern and the blue conversion pattern, and the red conversion pattern and the blue conversion pattern may not be formed. A red color conversion pattern for converting to may be formed.

  Examples of the color conversion layer include those containing a fluorescent material that absorbs light from the light emitting layer and emits fluorescence and a binder resin.

As the fluorescent material used in the present invention, for example, fluorescent dyes, fluorescent pigments, fluorescent dyes and the like can be used. The fluorescent material may be an organic fluorescent material or an inorganic fluorescent material, but it is preferable to use an organic fluorescent material because the fluorescence color is clear.
The fluorescent dye absorbs light in the near ultraviolet region or visible region and emits visible light having a different wavelength as fluorescence. This fluorescent dye is appropriately selected according to the target color conversion layer.
For example, when a blue light-emitting layer is used as a light-emitting layer in an organic EL display device, a fluorescent dye that absorbs light in a blue or blue-green region and emits fluorescence in a red region is used. A fluorescent dye that absorbs light in the blue or blue-green region and emits fluorescence in the green region is also used.
For example, when a white light-emitting layer is used as a light-emitting layer in an organic EL display device, since white light emission is usually composed of light in a blue region and a red region, it absorbs light in a blue or blue-green region. A fluorescent dye that emits fluorescence in the green region is used.
Examples of fluorescent dyes that absorb light in the blue to blue-green region emitted from the light emitting layer and emit fluorescence in the red region include rhodamine B, rhodamine 6G, rhodamine 3B, rhodamine 101, rhodamine 110, sulforhodamine, basic violet 11, Rhodamine dyes such as Basic Red 2, cyanine dyes, pyridine dyes such as 1-ethyl-2- [4- (p-dimethylaminophenyl) -1,3-butadienyl] -pyridinium perchlorate (pyridine 1), Or an oxazine pigment | dye etc. are mentioned. Furthermore, various dyes (direct dyes, acid dyes, basic dyes, disperse dyes, etc.) can be used if they are fluorescent.
Examples of fluorescent dyes that absorb blue to blue-green light emitted from the light emitting layer and emit green light include 3- (2′-benzothiazolyl) -7-diethylaminocoumarin (coumarin 6), 3- (2'-Benzimidazolyl) -7-N, N-diethylaminocoumarin (coumarin 7), 3- (2'-N-methylbenzimidazolyl) -7-N, N-diethylaminocoumarin (coumarin 30), 2, 3, 5 , 6-1H, 4H-tetrahydro-8-trifluoromethylquinolidine (9,9a, 1-gh) coumarin (coumarin 153), or the like, or basic yellow 51 which is a coumarin dye-based dye, and solvent Examples thereof include naphthalimide dyes such as yellow 11 and solvent yellow 116. Furthermore, various dyes (direct dyes, acid dyes, basic dyes, disperse dyes, etc.) can be used if they are fluorescent.
Furthermore, the fluorescent dye is kneaded in advance in polymethacrylate, polyvinyl chloride, vinyl chloride-vinyl acetate copolymer resin, alkyd resin, aromatic sulfonamide resin, urea resin, melamine resin, benzoguanamine resin, and a mixture of these resins. The pigment may be made into a fluorescent pigment. In addition, these fluorescent dyes and fluorescent pigments may be used alone or in combination of two or more in order to adjust the hue of fluorescence.

  The fluorescent material is contained in the range of 0.01 to 5% by weight, more preferably 0.1 to 2% by weight, based on the weight of the color conversion pattern. If the fluorescent dye content is too low, sufficient wavelength conversion cannot be performed, and if the fluorescent dye content is too high, color conversion efficiency may decrease due to effects such as concentration quenching. .

  The binder resin used for the color conversion layer is preferably a resin having a visible light transmittance of 50% or more. In addition, about resin, since it is the same as that of what was described in the term of the said planarization part, description here is abbreviate | omitted.

  In the present invention, the color conversion layer may be a film in which a fluorescent material is dispersed in ultrafine particles. Since a film in which a fluorescent material is dispersed in ultrafine particles contains almost no organic material, degassing hardly occurs even when exposed to a high temperature, and generation of dark spots can be prevented. Further, since the average particle diameter of the ultrafine particles is smaller than the wavelength in the visible light region, light scattering by the ultrafine particles can be suppressed, and a color conversion layer having high transparency and excellent color characteristics can be obtained. . From the viewpoint of low degassing property, the color conversion layer is preferably a film in which a fluorescent material is dispersed in ultrafine particles.

As the fluorescent material used in this case, for example, a fluorescent pigment, a fluorescent pigment, a fluorescent dye, or the like can be used. The fluorescent material may be an organic fluorescent material or an inorganic fluorescent material, but it is preferable to use an organic fluorescent material because the fluorescence color is clear. Here, even if the fluorescent material is an organic substance, the amount of the fluorescent material contained in the color conversion layer is very small compared to the content of the ultrafine particles, so the degassing component from the organic fluorescent material is a trace amount, This is not considered to be a major cause of dark spots. As the fluorescent material, those described above can be used.
Further, the content of the fluorescent material is set to 0.01 to 5% by weight, more preferably 0.1 to 5% by weight based on the weight of each color conversion pattern. This is because if the content of the fluorescent material is too low, sufficient wavelength conversion cannot be performed, and if the content of the fluorescent material is too high, the color conversion efficiency may decrease due to concentration quenching or the like. When the color conversion layer is a film in which a fluorescent material is dispersed in ultrafine particles, the dispersibility of the fluorescent material can be improved by the ultrafine particles, so that concentration quenching hardly occurs, and the above-described fluorescent material and binder resin It is possible to increase the content of the fluorescent material as compared with the color conversion layer containing.

  The thickness of the color conversion layer is not particularly limited as long as wavelength conversion can be performed. Specifically, the thickness can be set within a range of 500 nm to 50 μm, and preferably 1 μm to 10 μm. Is within the range. This is because if the thickness of the color conversion layer is too thick, the transparency may be lowered, or peeling from the substrate or the like may occur. Furthermore, if the thickness of the color conversion layer is too thick, the level difference due to the pattern-like color conversion layer becomes large, and flattening by the flattening part may be difficult. When the color conversion layer is a film in which a fluorescent material is dispersed in ultrafine particles, the content of the fluorescent material can be made relatively large as described above. It is possible to perform wavelength conversion sufficiently. On the other hand, if the thickness of the color conversion layer is thinner than the above range, there is a possibility that sufficient wavelength conversion cannot be performed.

As a method for forming a color conversion layer containing a fluorescent material and a binder resin, a general method for forming a color filter, for example, a photolithography method, an inkjet method, a printing method, or the like can be used.
When forming a color conversion layer that is a film in which a fluorescent material is dispersed in ultrafine particles, a coating for forming a color conversion layer comprising an ultrafine particle dispersion in which ultrafine particles and a fluorescent material are dispersed or dissolved in a solvent. It is preferable to form the color conversion layer by applying a working solution and baking. That is, the color conversion layer is preferably a coating film in which a fluorescent material is dispersed in ultrafine particles. By forming the color conversion layer by such a method, the sintering temperature can be lowered to a temperature lower than the heat resistance temperature of the colored layer or the color conversion layer due to the size effect unique to the ultrafine particles. Therefore, the color conversion layer excellent in low degassing property can be obtained without narrowing the choice of the colorant used in the color layer and the fluorescent material used in the color conversion layer.

  Further, when a transmission pattern is formed instead of each color conversion pattern, this transmission pattern may be made of the above-described resin or a film formed of ultrafine particles. A permeation pattern, which is a film formed of ultrafine particles, has the advantage of being excellent in low degassing properties. Note that the film formed of ultrafine particles is the same as that described in the section of the flattening portion, and thus description thereof is omitted here.

4). Barrier layer In the present invention, for example, as shown in FIG. 3, a barrier layer 6 may be formed on the colored layer 2 or the color conversion layer 5. Thereby, the barrier property of the color filter for organic EL elements can be improved. In particular, when the flattened portion, the colored layer, and the color conversion layer described above do not use ultrafine particles and do not have low degassing properties, it is preferable to form a barrier layer.

The material for forming the barrier layer used in the present invention may be any material that is generally used as a barrier layer in an organic EL display device, and examples thereof include inorganic oxides, inorganic nitrides, and inorganic oxynitrides. it can. Specifically, inorganic oxides include indium oxide, silicon oxide, aluminum oxide, titanium oxide, tantalum oxide, zinc oxide, magnesium oxide, tin oxide, yttrium oxide, germanium oxide, calcium oxide, boron oxide, strontium oxide, and oxide. Examples include barium, lead oxide, zirconium oxide, sodium oxide, lithium oxide, and potassium oxide. Examples of the inorganic nitride include silicon nitride, aluminum nitride, titanium nitride, and silicon carbonitride. Examples of inorganic oxynitrides include silicon oxynitride. These may be used alone or in combination of two or more.
Among these, at least one selected from the group consisting of silicon oxide, silicon nitride, and silicon oxynitride is preferably used. This is because these materials have good adhesion to the substrate and the second inorganic insulating layer.

  The barrier layer may be a single layer, or a plurality of layers may be laminated in order to improve barrier properties. Moreover, as a combination in the case of stacking, the same kind or different kinds may be used.

When the color filter for organic EL elements of the present invention is used in an organic EL display device, the barrier layer preferably has transparency because light is extracted from the substrate side. Specifically, the transmittance of the barrier layer in the visible light region is preferably 60% or more, more preferably 80% or more, and particularly preferably 90% or more.
In addition, the said transmittance | permeability is an average value of the value measured using Shimadzu Corporation Corp. UV-3100 within the wavelength range of 380 nm-800 nm.

  The thickness of such a barrier layer is not particularly limited as long as it has a barrier property against gas generated from water vapor, oxygen, a colored layer, and the like and satisfies the above-described permeability. The material is appropriately selected depending on the materials described above. Usually, it exists in the range of 5 nm-5000 nm, Preferably it exists in the range of 5 nm-500 nm. Further, when aluminum oxide or silicon oxide is used, it is more preferably in the range of 10 nm to 300 nm. This is because if the thickness of the barrier layer is too thin, it is difficult to obtain a desired barrier property. On the other hand, if the thickness of the barrier layer is too thick, cracks or the like may occur during the formation of the barrier layer, and the transmittance may decrease.

  Examples of the method for forming the barrier layer include a PVD method (physical vapor deposition method) such as a sputtering method, a vacuum vapor deposition method, and an ion plating method, a CVD method (chemical vapor deposition method), and a dipping method.

5. Substrate The substrate used in the present invention is preferably transparent in order to extract light from the substrate side when an organic EL display device is formed using the color filter for organic EL elements of the present invention. Moreover, it is preferable that a board | substrate has solvent resistance and heat resistance, and is excellent in dimensional stability. This is because it can be made stable even when a colored layer or the like is formed on the substrate.

  As the transparent substrate, for example, a glass substrate or a film or sheet formed of an organic material can be used.

  The glass substrate is not particularly limited as long as it has high transparency to visible light. For example, the glass substrate may be an unprocessed glass substrate or a processed glass substrate. As the glass substrate, both alkali glass and non-alkali glass can be used. However, when impurities are a problem, it is preferable to use non-alkali glass such as Pyrex (registered trademark) glass. The type of the processed glass substrate is appropriately selected according to the use of the color filter for the organic EL element of the present invention. For example, a transparent glass substrate coated or stepped. Etc.

  The thickness of the glass substrate is preferably within a range of 20 μm to 2 mm. Especially, when using as a flexible board | substrate, it is preferable to exist in the range of 20 micrometers-200 micrometers, and when using as a rigid board | substrate, it is preferable to exist in the range of 200 micrometers-2 mm.

Examples of the organic material used for the transparent substrate include polyarylate resin, polycarbonate resin, crystallized polyethylene terephthalate resin, polyethylene terephthalate resin, polyethylene naphthalate resin, UV curable methacrylic resin, polyether sulfone resin, and polyether ether. Examples include ketone resins, polyetherimide resins, polyphenylene sulfide resins, and polyimide resins.
Further, as the transparent substrate, for example, the above-described organic material, for example, cyclic polyolefin resin, polystyrene resin, acrylonitrile-styrene copolymer (AS resin), acrylonitrile-butadiene-styrene copolymer (ABS resin), poly (Meth) acrylic resins, polycarbonate resins, polyester resins such as polyethylene terephthalate and polyethylene naphthalate, polyamide resins such as various nylons, polyurethane resins, fluorine resins, acetal resins, cellulose resins, polyethers Two or more types can be used in combination with a sulfone resin or the like.

  When a transparent substrate is formed using the organic material as described above, the thickness of the substrate is preferably in the range of 10 μm to 500 μm, more preferably in the range of 50 to 400 μm, and particularly preferably in the range of 100 to 300 μm. . This is because if the thickness of the substrate is too thick, the impact resistance is inferior, and winding becomes difficult during winding. Moreover, if the thickness of the substrate is too thin, mechanical suitability may be poor.

  In the present invention, it is preferable to clean and use the substrate. As the cleaning method, it is preferable to perform ultraviolet light irradiation treatment with oxygen, ozone, etc., plasma treatment, argon sputtering treatment, or the like. This is because moisture and oxygen are not adsorbed, and dark spots can be reduced and the life of the organic EL element can be extended.

B. Next, a method for producing a color filter for organic EL elements of the present invention will be described.
The method for producing a color filter for an organic EL device according to the present invention includes a substrate, a colored layer formed in a pattern on the substrate, and a planarizing portion formed between the colored layers. And a surface treatment step of polishing the surfaces of the colored layer and the planarized portion after forming the colored layer and the planarized portion on the substrate.

  FIG. 6 is a diagram showing an example of a method for producing a color filter for organic EL elements of the present invention. In the present invention, first, the colored layer 2 is formed in a pattern on the substrate 1, and the flattened portion 3 is formed so as to fill the step due to the patterned colored layer 2 (FIG. 6A). In FIG. 6A, the flattened portion 3 is also formed on the colored layer 2 so as to sufficiently fill the level difference caused by the previously formed colored layer 2. Next, the surfaces of the colored layer 2 and the flattening portion 3 are polished with the sandpaper 11 (FIG. 6B, surface treatment step). At this time, polishing is performed up to a portion indicated by a broken line L, that is, until all the flattened portion 3 formed on the colored layer 2 is removed. Thereby, the color layer 2 surface is exposed, and a color filter for organic EL elements in which the planarizing portion 3 does not exist on the colored layer 2 can be obtained (FIG. 6C).

  According to the present invention, even when the flattened portion is formed on the colored layer, the flattened portion on the colored layer is removed by polishing the surfaces of the colored layer and the flattened portion. Since the layer can be exposed, a color filter for an organic EL element having high transparency can be obtained. In particular, when the flattened portion has a light shielding property, the transparency can be effectively improved. Further, even when there are steps on the surface of the colored layer and the flattened portion, the surface can be easily flattened by polishing the surfaces of the colored layer and the flattened portion. For this reason, in the organic EL display device using the color filter for organic EL elements obtained by the present invention, it is possible to prevent a short circuit between the electrodes.

  The method for producing a color filter for an organic EL element of the present invention includes a colored layer forming step of forming a patterned colored layer on a substrate, and a flattened portion forming step of forming a flattened portion at a predetermined position on the substrate. And the surface treatment step. Hereinafter, each step will be described.

1. Colored layer forming step The colored layer forming step in the present invention is a step of forming a patterned colored layer on a substrate. In addition, since it described in the term of the colored layer of the said "A. Color filter for organic EL elements" about the formation method of a colored layer, description here is abbreviate | omitted.

In the present invention, in the colored layer forming step, a coating solution for forming a colored layer comprising an ultrafine particle dispersion in which ultrafine particles and a colorant are dispersed in a solvent is applied on a substrate, and baked to form a pattern. A step of forming a colored layer is preferred.
The ultrafine particle dispersion is a solution in which ultrafine particles are dispersed individually and uniformly, and no aggregation of the ultrafine particles occurs. For this reason, since the ultrafine particles function as a dispersion medium for dispersing the colorant, the dispersibility of the colorant is also good. In addition, since the ultrafine particles play a role like a binder, it is not necessary to use a resin as a binder, and a colored layer having excellent low degassing properties can be obtained. Thereby, it is possible to obtain an organic EL element substrate in which dark spots are hardly generated.
Furthermore, since the ultrafine particles are densely sintered at a temperature much lower than the general sintering temperature due to the size effect unique to the ultrafine particles, the colored layer can be fired at a temperature lower than the heat resistance temperature. Therefore, it has the advantage that the choice of the coloring agent used for a colored layer spreads.
In addition, since the average particle size of the ultrafine particles in the present invention is smaller than the wavelength in the visible light region, light scattering by the ultrafine particles can be suppressed, and a colored layer having high transparency and excellent color characteristics is formed. be able to.

  As described above, the ultrafine particle dispersion used in the present invention is obtained by dispersing ultrafine particles individually and uniformly, and is prepared by dispersing ultrafine particles and a colorant in a solvent. At this time, for example, ultrafine particles may be prepared by a gas evaporation method, and a coloring agent may be added later to the dispersion in which the obtained ultrafine particles are dispersed in a solvent. At the time of production, a dispersion containing ultrafine particles and a colorant dispersed in a solvent may be obtained using a solution containing a colorant and a solvent.

The ultrafine particles are the same as those described in the section of the flattening section of the “A. Color filter for organic EL elements”, and the colorant is the same as that described in “A. Color filter for organic EL elements”. Since it is the same as that described in the section of the colored layer, description thereof is omitted here.
Here, the average particle diameter of the ultrafine particles used in the ultrafine particle dispersion is a value measured by a laser method. The average particle diameter is generally used to indicate the particle size of the particles, and the laser method is to disperse the particles in a solvent and thin the scattered light obtained by applying a laser beam to the dispersion solvent. This is a method of measuring the average particle size, particle size distribution, etc. by calculation. The average particle size is a value measured using a particle size analyzer Microtrac UPA Model-9230 manufactured by Leeds & Northrup as a particle size measuring device by a laser method.

The method for producing the ultrafine particles is not particularly limited, and for example, a gas evaporation method, a wet reduction method, a thermal reduction method by spraying an organometallic compound in a high temperature atmosphere, or the like is used.
In the gas evaporation method, metals and the like are evaporated in a gas atmosphere and in a gas phase in which solvent vapor coexists, and the evaporated metals and the like are brought into contact with a reaction gas (oxygen, nitrogen, etc.) as necessary. Is condensed into uniform ultrafine particles and dispersed in a solvent to obtain a dispersion. In this gas evaporation method, ultrafine particles having a uniform particle size can be obtained. In order to prepare an ultrafine particle dispersion using ultrafine particles obtained by a gas evaporation method as a raw material, substitution may be performed with a solvent used for the ultrafine particle dispersion. Further, a dispersant may be added to increase the dispersion stability of the ultrafine particles. As a result, the ultrafine particles are dispersed individually and uniformly, and a fluid state is maintained. For the gas evaporation method, reference can be made to Japanese Patent No. 2651537, Japanese Patent Application Laid-Open No. 2002-121437, Japanese Patent Application Laid-Open No. 2005-183054, and the like.

The solvent used in the ultrafine particle dispersion is appropriately selected depending on the ultrafine particles to be used. For example, methanol, ethanol, propanol, isopropyl alcohol, butanol, hexanol, heptanol, octanol, decanol, cyclohexanol, terpineol Alcohols such as ethylene glycol and propylene glycol; ketones such as acetone, methyl ethyl ketone and diethyl ketone; esters such as ethyl acetate, butyl acetate and benzyl acetate; ether alcohols such as methoxyethanol and ethoxyethanol; Ethers such as dioxane and tetrahydrofuran; acid amides such as N, N-dimethylformamide; benzene, toluene, xylene, trimethylbenzene, dodecylben Aromatic hydrocarbons such as hexane; long-chain alkanes such as hexane, heptane, octane, nonane, decane, undecane, tridecane, tetradecane, pentadecane, hexadecane, octadecane, nonadecane, eicosane, trimethylpentane; cyclohexane, cycloheptane, And cyclic alkanes such as cyclooctane; Furthermore, water can also be used.
These may be used alone or as a mixed solvent. For example, it may be a mineral spirit that is a mixture of long-chain alkanes.

Furthermore, it is preferable that the solvent evaporates during drying and baking performed after applying an ultrafine particle dispersion described later. In particular, the boiling point of the solvent is preferably 120 ° C or higher, more preferably 150 ° C or higher, further preferably 170 ° C or higher, and most preferably 190 ° C or higher. This is because if the boiling point of the solvent is lower than the above range, for example, it is easy to evaporate at the time of drying, so that the ultrafine particles are likely to aggregate and a uniform film may not be obtained. On the other hand, the upper limit of the boiling point of the solvent is about 350 ° C. from the upper limit of the firing temperature.
Among these solvents, terpineol, decane, dodecane, tridecane, tetradecane, dodecylbenzene, mineral spirit, and the like are preferably used.

  What is necessary is just to select the usage-amount of the said solvent suitably according to the ultrafine particle to be used so that it can apply | coat easily and a desired film thickness can be obtained. Specifically, the concentration of the ultrafine particles in the ultrafine particle dispersion is preferably in the range of 1 to 50 wt%, more preferably in the range of 10 to 40 wt%. This is because if the concentration of the ultrafine particles is less than the above range, a desired film thickness may not be obtained. On the other hand, when the concentration of the ultrafine particles exceeds the above range, the viscosity of the ultrafine particle dispersion is increased and the fluidity is lowered, so that the flatness of the colored layer may be impaired.

  Further, the viscosity of the ultrafine particle dispersion is preferably 100 cP or less at 20 ° C., and more preferably 10 cP or less. This is because a flat film can be formed if the viscosity is within the above range.

  The coating method for the colored layer forming coating solution may be any method that can be applied to a uniform thickness, such as spin coating, spray coating, dip coating, roll coating, ink jet, and flexographic printing. Can be mentioned.

  Moreover, after apply | coating the coating liquid for colored layer formation and forming a coating film, a coating film may be dried and a solvent may be removed. The drying temperature is appropriately selected according to the type of solvent, but is usually about 80 ° C to 150 ° C.

The firing temperature of the coating film is appropriately selected depending on the type of ultrafine particles used, etc., but is preferably about 150 ° C. to 350 ° C., more preferably in the range of 150 ° C. to 250 ° C. More preferably, it is in the range of 150 ° C to 220 ° C. This is because if the firing temperature is too low, the ultrafine particles may not be sufficiently sintered, and if the firing temperature is too high, the substrate or the colored layer may be thermally damaged. The temperature required to sinter the inorganic oxide constituting the ultrafine particles alone is generally about 400 to 700 ° C., but in the present invention, it is extremely low as 150 ° C. to 350 ° C. due to the size effect of the ultrafine particles. Sinter at temperature.
Also, the firing time is appropriately selected depending on the type of ultrafine particles used and the like, but is usually about 10 minutes to 1 hour, preferably 15 minutes to 30 minutes.

  The atmosphere for firing is appropriately selected depending on the type of ultrafine particles. In this step, baking may be performed in an oxidizing atmosphere, or baking may be performed in an atmosphere in which ultrafine particles are not oxidized, and then baking may be performed in an oxidizing atmosphere. That is, it may be fired by a one-stage process or may be fired by a two-stage process. This is because the firing by the two-stage process can avoid that only the surface of the ultrafine particles is further oxidized and the sintering becomes insufficient. In addition, since firing is performed in two stages, a denser colored layer can be formed by low-temperature firing.

Examples of the atmosphere in which the ultrafine particles are not oxidized include a vacuum atmosphere, an inert gas atmosphere, and a reducing atmosphere.
Examples of the inert gas atmosphere include inert atmospheres such as rare gas, carbon dioxide, and nitrogen.
Examples of the reducing atmosphere include hydrogen, carbon monoxide, lower alcohol, and the like. Examples of the lower alcohol include lower alcohols having 1 to 6 carbon atoms such as methanol, ethanol, propanol, butanol, hexanol and the like.
The vacuum atmosphere is, for example, an inert gas such as a rare gas, carbon dioxide, or nitrogen; an oxidizing gas such as oxygen or water vapor; a reducing gas such as hydrogen, carbon monoxide, or a lower alcohol; or the above inert gas and an oxidizing gas. Or a mixed gas with a reducing gas or a reducing gas. When an oxidizing gas is introduced in a vacuum atmosphere, there is an effect that only the organic compound (solvent or dispersant) adhering to the ultrafine particles is burned without oxidizing the ultrafine particles. The vacuum state may be simply drawn by a pump, or once pumped, an inert gas, a reducing gas, or an oxidizing gas may be introduced. Firing in a vacuum atmosphere can usually be performed at about 10 ⁻⁵ to 10 ³ Pa.

  The oxidizing atmosphere may contain oxygen, water vapor, oxygen-containing gas (for example, air), water vapor-containing gas, and the like.

Further, the coating film may be dried after firing in an atmosphere in which the ultrafine particles are not oxidized and before firing in an oxidizing atmosphere. This is because the solvent and the dispersant can be removed. The removal of the solvent and the dispersant may be performed at the time of firing.
Further, after firing in an oxidizing atmosphere, firing may be performed in a reducing atmosphere.
Further, ultraviolet irradiation may be performed during firing. More effective in terms of time reduction and low temperature. In the firing, so-called plasma sintering using atmospheric pressure plasma or the like can be used.

  In the present invention, for example, a resist method, a discharge method, a printing method, or the like can be used as a patterning method for the colored layer.

In the resist method, a colored layer can be formed in a pattern by applying a resist on the colored layer and performing mask exposure, development, acid etching, and resist stripping. When using the resist method, the resist may be applied onto the dried coating film, or the resist may be applied onto the fired film. That is, the order of coating, drying, baking, and patterning by a resist method may be used, and the order of coating, drying, patterning by a resist method, and baking may be used.
Further, in this case, as the ultrafine particles used in the colored layer forming coating solution, those dissolved in an acidic etching solution are used. Examples of such ultrafine particles include inorganic oxides, among which at least one selected from the group consisting of indium oxide, zinc oxide, and tin oxide is preferably used. This is because it is not necessary to use a strong acid etching solution that dissolves a substrate such as hydrofluoric acid among acidic etching solutions.
In addition, coating, drying, baking, and patterning by a resist method may be repeated for each colored pattern. After coating, drying, and patterning by a resist method are repeated for each colored pattern, the entire colored layer is You may bake.

In the discharge method, the colored layer can be formed into a pattern by coating the colored layer forming coating solution according to the pattern. Examples of the discharge method include an ink jet method. In this case, it is preferable to form a hydrophilic / hydrophobic pattern on the surface of the member to which the colored layer forming coating solution is applied. This is because the colored layer forming coating solution used in the present invention has a relatively low viscosity, and therefore, a fine pattern can be formed by coating along the hydrophilic / hydrophobic pattern.
In this case, coating, drying, and firing may be repeated for each colored pattern, and the entire colored layer may be fired after repeated coating and drying for each colored pattern. From the viewpoint of simplicity, it is preferable that the entire colored layer is baked after repeated application and drying for each colored pattern.

The printing method may be any method that can print a colored layer-forming coating solution having a relatively low viscosity to a uniform thickness, and examples thereof include a flexographic printing method.
In the above-described ejection method and printing method, any ultrafine particles can be used as long as they are described in the section of the flattened portion of the “A. Color filter for organic EL elements”.

  Among these, the ink jet method is preferably used because the manufacturing process is simple.

2. Flattening portion forming step The flattening portion forming step in the present invention is a step of forming a flattening portion at a predetermined position on the substrate. In the present invention, depending on the type of the flattened portion, whether the flattened portion forming step is performed before the colored layer forming step or after the colored layer forming step is appropriately selected. For example, in the case of forming a planarized portion having transparency, the planarized portion forming step is performed after the colored layer forming step. Further, when the flattened portion has a light shielding property and is a light shielded portion, the flattened portion forming step is performed before the colored layer forming step. Further, when the flattened portion has a light shielding property and the light shielding portion and the transmissive portion are laminated, the light shielding portion is formed before the colored layer forming step, and the transmissive portion is removed after the colored layer forming step. Form. In any case, the flattened portion is formed so as to fill the step due to the patterned colored layer.
In addition, since it described in the term of the planarization part of the said "A. color filter for organic EL elements" about the formation method of the planarization part, description here is abbreviate | omitted.

In the present invention, the step of forming the flattening portion is to apply a flattening portion-forming coating liquid composed of an ultrafine particle dispersion in which ultrafine particles are dispersed in a solvent on the substrate, and then baked to form the flattening portion. It is preferable that it is the process of forming.
As in the case of the colored layer forming step, by using a coating liquid for forming a flattened part made of an ultrafine particle dispersion, it is possible to form a flattened part having excellent low degassing properties and generate dark spots. It is possible to obtain a substrate for an organic EL element that is difficult to perform. In addition, due to the size effect peculiar to ultrafine particles, the ultrafine particles are densely sintered at a temperature much lower than the general sintering temperature, so that the colored layer can be fired at a temperature lower than the heat resistance temperature.

The coating liquid for forming a flattened portion made of an ultrafine particle dispersion varies depending on the type of the flattened portion. For example, for the planarizing part having permeability, a coating liquid for forming a planarizing part made of an ultrafine particle dispersion in which ultrafine particles are dispersed in a solvent is used. Further, for example, when the flattening part has a light shielding property and is a light shielding part, a coating liquid for forming a flattening part comprising an ultrafine particle dispersion in which ultrafine particles and a black colorant are dispersed in a solvent is used. . Further, for example, when the flattening part has a light shielding property and the light shielding part and the transmissive part are laminated, the flattening part forming coating liquid for forming the light shielding part is used for the light shielding part. The flattened portion forming coating liquid for forming the flattened portion having the above-described permeability is used for the transparent portion.
The fine particles are the same as those described in the section of the flattening portion of the above-mentioned “A. Color filter for organic EL element”, and other points of the ultrafine particle dispersion and the flattening portion forming coating liquid Since the coating method, baking method, patterning method, and the like are the same as those described in the section of the colored layer forming step, description thereof is omitted here.

  If the desired thickness cannot be obtained by applying the flattening portion forming coating solution once, the flattening portion is further formed after applying, drying, and baking the flattening portion forming coating solution. The thickness of the flattened portion can be increased by applying, drying, and baking the coating liquid for application. Further, the thickness of the flattening portion can be increased by applying and drying the flattening portion forming coating solution and then drying and then baking the flattening portion forming coating solution. .

3. Surface treatment process The surface treatment process in this invention is a process of grind | polishing the surface of the said colored layer and the planarization part, after forming a colored layer and a planarization part on a board | substrate.

As a polishing method, for example, a method using a sandpaper or the like in which suitable abrasive grains are dispersed and adhered on a sheet, a chemical polishing method or a mechanical polishing method, or chemical mechanical polishing (CMP) using them in combination. Etc. can be used.
The chemical polishing method is performed by supplying an etching liquid as an abrasive to an abrasive member made of a foam such as cloth, non-woven fabric, or polyurethane resin.
The mechanical polishing method uses, for example, cloth, non-woven fabric, or polyurethane resin as a polishing member and impregnates colloidal silica or fine powder of cerium oxide as an abrasive, or uses colloidal silica or cerium oxide as an abrasive. This is performed by supplying a dispersion in which is dispersed.

  In any of the above methods, the polishing is carried out by bringing the polishing member into contact with the surface of the colored layer and the flattened part while moving the target object and the polishing member relatively by rotating the target object. It is preferable to carry out the process while supplying the abrasive. Moreover, it is preferable to grind | polish until a planarization part does not exist on a colored layer.

C. Organic EL Display Device Next, the organic EL display device of the present invention will be described.
The organic EL display device of the present invention includes the above-described color filter for organic EL elements, a transparent electrode layer formed on the color filter for organic EL elements, and formed on the transparent electrode layer, and includes at least a light emitting layer. It has an organic EL layer and a back electrode layer formed on the organic EL layer.

  FIG. 2 shows an example of the organic EL display device of the present invention. As shown in FIG. 2, the organic EL display device 20 includes an organic EL element color filter 10, a transparent electrode layer 21 formed on the organic EL element color filter 10, and the transparent electrode layer 21. The organic EL layer 22 is formed in a pattern, and the back electrode layer 23 is formed on the organic EL layer 22. An insulating layer 24 is formed on the transparent electrode layer 21 and between the patterned organic EL layers 22. This insulating layer 24 is a layer provided to prevent the transparent electrode layer 21 and the back electrode layer 23 from contacting each other. Further, a partition wall 25 is formed on the insulating layer 24. The portion where the organic EL layer 22 is formed is a display area. The organic EL element color filter 10 has a patterned colored layer 2 formed on a substrate 1 and a planarized portion 3 formed between the patterned colored layers 2.

According to the present invention, since the above-described color filter for organic EL elements is used, an organic EL display device having high luminance and excellent color display characteristics can be obtained. Further, the occurrence of defects such as dark spots can be suppressed, and a good image display is possible.
Hereinafter, each configuration of the organic EL display device will be described. The color filters for organic EL elements are the same as those described in the section “A. Color filters for organic EL elements”, and thus the description thereof is omitted here.

1. Organic EL Layer The organic EL layer used in the present invention is composed of one or more organic layers including at least a light emitting layer. That is, the organic EL layer is a layer including at least a light emitting layer, and the layer configuration is a layer having one or more organic layers. Usually, when an organic EL layer is formed by a wet method by coating, it is often difficult to stack a large number of layers in relation to a solvent, so that it is often formed of one or two organic layers. However, it is possible to further increase the number of layers by devising an organic material so that the solubility in a solvent is different or by combining a vacuum deposition method.

Examples of the organic layer formed in the organic EL layer other than the light emitting layer include charge injection layers such as a hole injection layer and an electron injection layer. Furthermore, examples of the other organic layers include a charge transport layer such as a hole transport layer that transports holes to the light-emitting layer and an electron transport layer that transports electrons to the light-emitting layer. In many cases, it is formed integrally with the charge injection layer by imparting a charge transporting function. In addition, as an organic layer formed in the organic EL layer, it prevents holes or electrons from penetrating like a carrier block layer and further prevents diffusion of excitons and confines excitons in the light emitting layer. And a layer for increasing the recombination efficiency.
Hereinafter, each structure of such an organic EL layer will be described.

(1) Light emitting layer The light emitting layer used in the present invention has a function of emitting light by providing a recombination field of electrons and holes. As the material for forming the light emitting layer, a dye-based light-emitting material, a metal complex-based light-emitting material, or a polymer-based light-emitting material can be generally used.

  Examples of dye-based light emitting materials include cyclopentadiene derivatives, tetraphenylbutadiene derivatives, triphenylamine derivatives, oxadiazole derivatives, pyrazoloquinoline derivatives, distyrylbenzene derivatives, distyrylarylene derivatives, silole derivatives, thiophene ring compounds, pyridine rings Examples thereof include compounds, perinone derivatives, perylene derivatives, oligothiophene derivatives, trifumanylamine derivatives, coumarin derivatives, oxadiazole dimers, pyrazoline dimers, and the like.

Metal complex light emitting materials include aluminum quinolinol complex, benzoquinolinol beryllium complex, benzoxazole zinc complex, benzothiazole zinc complex, azomethyl zinc complex, porphyrin zinc complex, europium complex, iridium metal complex, platinum metal complex, etc. The metal has Al, Zn, Be, Ir, Pt, etc., or a rare earth metal such as Tb, Eu, Dy, etc., and the ligand has an oxadiazole, thiadiazole, phenylpyridine, phenylbenzimidazole, quinoline structure, etc. A metal complex etc. can be mentioned. Specifically, tris (8-quinolinol) aluminum complex (Alq ₃ ) can be used.

  Furthermore, as the polymer-based light emitting material, polyparaphenylene vinylene derivatives, polythiophene derivatives, polyparaphenylene derivatives, polysilane derivatives, polyacetylene derivatives, polyvinylcarbazole, polyfluorenone derivatives, polyfluorene derivatives, polyquinoxaline derivatives, polydialkylfluorene derivatives, And copolymers thereof. Moreover, what polymerized the said pigment-type luminescent material and metal complex type | system | group luminescent material is also mentioned.

  Among the above, the light emitting material used in the present invention is preferably a metal complex light emitting material or a polymer light emitting material, and more preferably a polymer light emitting material. Of the polymer light emitting materials, a conductive polymer having a π-conjugated structure is preferable. Examples of the conductive polymer having such a π-conjugated structure include polyparaphenylene vinylene derivatives, polythiophene derivatives, polyparaphenylene derivatives, polysilane derivatives, polyacetylene derivatives, polyfluorenone derivatives, polyfluorene derivatives, polyquinoxaline derivatives as described above. , Polydialkylfluorene derivatives, and copolymers thereof.

  The thickness of the light emitting layer is not particularly limited as long as it can provide a function of emitting light by providing a recombination field between electrons and holes, and can be, for example, about 1 nm to 200 nm. .

  Further, a dopant that emits fluorescence or phosphorescence may be added to the light emitting layer for the purpose of improving the light emission efficiency and changing the light emission wavelength. Examples of such dopants include perylene derivatives, coumarin derivatives, rubrene derivatives, quinacridone derivatives, squalium derivatives, porphyrin derivatives, styryl dyes, tetracene derivatives, pyrazoline derivatives, decacyclene, phenoxazone, quinoxaline derivatives, carbazole derivatives, fluorene derivatives, and the like. Can be mentioned.

  The method for forming the light emitting layer is not particularly limited as long as it is a method capable of high-definition patterning. For example, vapor deposition method, printing method, inkjet method, spin coating method, casting method, dipping method, bar coating method, blade coating method, roll coating method, gravure coating method, flexographic printing method, spray coating method, and self-assembly method (Alternate adsorption method, self-assembled monolayer method) and the like. Among these, it is preferable to use a vapor deposition method, a spin coating method, and an ink jet method. Further, when the light emitting layer is patterned, it may be applied separately by a masking method for pixels having different light emission colors, or a partition may be formed between the light emitting layers. As a material for forming such a partition, a photocurable resin such as a photosensitive polyimide resin or an acrylic resin, a thermosetting resin, an inorganic material, or the like can be used. Furthermore, you may perform the process which changes the surface energy (wetting property) of the material which forms these partition walls.

(2) Charge injection / transport layer In the present invention, a charge injection / transport layer may be formed between the transparent electrode layer or the back electrode layer and the light emitting layer. The charge injecting and transporting layer here has a function of stably transporting charges from the transparent electrode layer or the back electrode layer to the light emitting layer, and the charge injecting and transporting layer is used as the transparent electrode layer or the back surface. By providing between the electrode layer and the light emitting layer, the injection of charges into the light emitting layer is stabilized, and the light emission efficiency can be increased.

  Examples of the charge injection transport layer include a hole injection transport layer that transports holes injected from the anode into the light emitting layer, and an electron injection transport layer that transports electrons injected from the cathode into the light emitting layer. Hereinafter, the hole injection / transport layer and the electron injection / transport layer will be described.

(I) Hole Injecting and Transporting Layer The hole injecting and transporting layer used in the present invention is either a hole injecting layer for injecting holes into the light emitting layer or a hole transporting layer for transporting holes. The hole injection layer and the hole transport layer may be laminated, or a single layer having both the hole injection function and the hole transport function may be used.

  The material used for the hole injecting and transporting layer is not particularly limited as long as it can stably transport holes injected from the anode into the light emitting layer. In addition to the exemplified compounds, phenylamine, starburst amine, phthalocyanine, vanadium oxide, molybdenum oxide, ruthenium oxide, aluminum oxide and other oxides, amorphous carbon, polyaniline, polythiophene, polyphenylene vinylene derivatives, etc. may be used. it can. Specifically, bis (N- (1-naphthyl-N-phenyl) benzidine (α-NPD), 4,4,4-tris (3-methylphenylphenylamino) triphenylamine (MTDATA), poly 3, 4-ethylenedioxythiophene-polystyrene sulfonic acid (PEDOT-PSS), polyvinyl carbazole (PVCz), etc. are mentioned.

  The thickness of the hole injecting and transporting layer is not particularly limited as long as the hole injecting holes from the anode and transporting the holes to the light emitting layer is sufficiently exhibited. It is preferable to be in the range of 5 nm to 1000 nm, especially in the range of 10 nm to 500 nm.

(Ii) Electron Injection / Transport Layer The electron injection / transport layer used in the present invention may be either an electron injection layer for injecting electrons into the light emitting layer or an electron transport layer for transporting electrons. A layer and an electron transport layer may be laminated, or a single layer having both an electron injection function and an electron transport function may be used.

  The material used for the electron injection layer is not particularly limited as long as the material can stabilize the injection of electrons into the light emitting layer. In addition to the compounds exemplified as the light emitting material of the light emitting layer, Aluminum lithium alloy, lithium fluoride, strontium, magnesium oxide, magnesium fluoride, strontium fluoride, calcium fluoride, barium fluoride, aluminum oxide, strontium oxide, calcium, polymethyl methacrylate, sodium polystyrene sulfonate, lithium, cesium, Alkali metals, alkali metal halides, alkali metal organic complexes, and the like, such as cesium fluoride, can be used.

  In addition, the thickness of the electron injection layer is not particularly limited as long as the electron injection function is sufficiently exerted.

On the other hand, the material used for the electron transport layer is not particularly limited as long as it is a material capable of transporting electrons injected from the cathode into the light emitting layer. For example, bathocuproine, bathophenanthroline, phenanthroline derivatives, A triazole derivative, an oxadiazole derivative, or a tris (8-quinolinol) aluminum complex (Alq ₃ ) can be given.

  Furthermore, as an electron injecting and transporting layer composed of a single layer having both an electron injecting function and an electron transporting function, a metal doped layer in which an alkali metal or an alkaline earth metal is doped on an electron transporting organic material is formed. This can be used as an electron injecting and transporting layer. Examples of the electron-transporting organic material include bathocuproin, bathophenanthroline, and phenanthroline derivatives. Examples of the metal to be doped include Li, Cs, Ba, and Sr.

2. Transparent electrode layer and back electrode layer The transparent electrode layer and back electrode layer used in the present invention are electrodes having opposite charges.
The transparent electrode layer is generally composed of a metal oxide thin film having transparency and conductivity. Examples of such metal oxides include indium tin oxide (ITO), indium oxide, zinc oxide, and tin oxide.
Moreover, a metal is generally used as the back electrode layer. Specifically, magnesium alloy (MgAg etc.), aluminum alloy (AlLi, AlCa, AlMg etc.), aluminum, alkaline earth metal (Ca etc.), alkali metal (K, Li etc.), etc. are mentioned.

  A transparent electrode layer and a back electrode layer can be formed using the formation method of a general electrode layer, for example, sputtering method, a vacuum evaporation method, etc. are mentioned.

3. Insulating layer In the present invention, an insulating layer may be formed in order to insulate the transparent electrode layer and the back electrode layer. This insulating layer is formed in a pattern as a non-display area.
Examples of the material for forming the insulating layer include a photocurable resin such as an ultraviolet curable resin and a thermosetting resin. Such an insulating layer can be formed using a resin composition containing the above resin. As a patterning method, a general method such as a photolithography method or a printing method can be used.

  The present invention is not limited to the above embodiment. The above-described embodiment is an exemplification, and the present invention has substantially the same configuration as the technical idea described in the claims of the present invention, and any device that exhibits the same function and effect is the present invention. It is included in the technical scope of the invention.

Hereinafter, the present invention will be specifically described using examples and comparative examples.
[Example]
(Formation of colored layer)
First, as a transparent substrate, 150 mm × 150 mm, 0.7 mm thick soda glass (manufactured by Central Glass Co., Ltd. Sn surface polished product) was prepared.

  When producing In particles by gas evaporation using high frequency induction heating under the condition of helium gas pressure of 0.5 torr, the production of In particles is 20: 1 (capacity ratio) of α-terpineol and dodecylamine. Steam was collected, cooled and collected to collect In fine particles, and a dispersion containing 20% by weight of In fine particles having an average particle diameter of 10 nm dispersed in an α-terpineol solvent in an independent state was prepared. Five volumes of acetone were added to 1 volume of this dispersion (colloidal solution) and stirred. The fine particles in the dispersion liquid settled by the action of polar acetone. After standing for 2 hours, the supernatant was removed, the same amount of acetone was added again and stirred, and after standing for 2 hours, the supernatant was removed. From this sediment, the residual solvent was completely removed, In fine particles having an average particle diameter of 10 nm were produced, and confirmed to be non-oxidized fine particles by X-ray diffraction. The fine particles were dispersed in tetradecane at a concentration of 60 wt% to obtain an ultrafine particle dispersion.

Thereafter, a green pigment (mixture of CI pigment green 36 and CI pigment yellow 83 (100: 10)) is further dispersed in the ultrafine particle dispersion at a concentration of 30 wt% in terms of solid content to form a green colored layer. A coating solution was prepared. This coating solution for forming a green colored layer was applied onto a transparent substrate by a spin coating method, and then the coating film was baked under conditions of 230 ° C. and 10 minutes under a reduced pressure of 1 × 10 ⁻³ Pa. Next, firing was performed at 230 ° C. for 60 minutes in an oxidizing atmosphere (atmosphere). The film thickness at this time was 1.5 μm.
Next, a photosensitive resist was applied onto the green colored layer by spin coating, and drying, mask exposure, development, and etching of the green colored layer were performed to form a green colored pattern. This green coloring pattern was a belt-like pattern having a width of 90 μm.

Similarly, a red pigment (a mixture of CI Pigment Red I77 and CI Pigment Yellow 83 (100: 20)) is dispersed in the ultrafine particle dispersion at a concentration of 30 wt% in terms of solid content to obtain a red colored layer. A forming coating solution was prepared. This coating solution for forming a red colored layer was applied onto the colored layer by a spin coating method, and then the coating film was baked under conditions of 230 ° C. and 10 minutes under a reduced pressure of 1 × 10 ⁻³ Pa. Next, firing was performed at 230 ° C. for 60 minutes in an oxidizing atmosphere (atmosphere). The film thickness at this time was 1.5 μm.
Next, a photosensitive resist was applied on the red colored layer by spin coating, and drying, mask exposure, development, and etching of the red colored layer were performed to form a red colored pattern. This red coloring pattern was a strip pattern having a width of 90 μm.

Further, in the same manner, a blue pigment (a mixture of CI pigment blue 15: 3 and CI pigment violet 23 (100: 5)) is dispersed in the ultrafine particle dispersion at a concentration of 30 wt% in terms of solid content. A colored layer forming coating solution was prepared. This blue colored layer-forming coating solution was applied onto the colored layer by a spin coating method, and then the coating film was baked under conditions of 230 ° C. and 10 minutes under a reduced pressure of 1 × 10 ⁻³ Pa. Next, firing was performed at 230 ° C. for 60 minutes in an oxidizing atmosphere (atmosphere). The film thickness at this time was 1.5 μm.
Next, a photosensitive resist was applied onto the blue colored layer by spin coating, and drying, mask exposure, development, and etching of the blue colored layer were performed to form a blue colored pattern. This blue coloring pattern was a strip pattern having a width of 90 μm.

(Formation of flat part)
When producing In particles by gas evaporation using high frequency induction heating under the condition of helium gas pressure of 0.5 torr, the production of In particles is 20: 1 (capacity ratio) of α-terpineol and dodecylamine. Steam was collected, cooled and collected to collect In fine particles, and a dispersion containing 20% by weight of In fine particles having an average particle diameter of 10 nm dispersed in an α-terpineol solvent in an independent state was prepared. Five volumes of acetone were added to 1 volume of this dispersion (colloidal solution) and stirred. The fine particles in the dispersion liquid settled by the action of polar acetone. After standing for 2 hours, the supernatant was removed, the same amount of acetone was added again and stirred, and after standing for 2 hours, the supernatant was removed. From this sediment, the residual solvent was completely removed, In fine particles having an average particle diameter of 10 nm were produced, and confirmed to be non-oxidized fine particles by X-ray diffraction. The fine particles were dispersed in tetradecane at a concentration of 30 wt% to obtain an ultrafine particle dispersion.

  Further, 300 g of the above ultrafine particle dispersion, 200 g of titanium black (13M-C manufactured by Mitsubishi Materials Corporation), 300 g of MBA (methoxybutyl acetate), colloidal silica (Snowtex NPC-ST manufactured by Nissan Chemical Co., Ltd.), 50 g of an average particle diameter of 10 to 20 nm) and 300 cc of zirconia beads (Showa Shell Sekiyu KK Microhaika Z Z300, diameter 0.3 mm) were added, and the mixture was dispersed in a sand mill at a rotor rotational speed of 1500 rpm for 2 hours. Thereafter, 20 g of a dispersant (Solsperse 24000, manufactured by Avicia Co., Ltd.) was added to the above dispersion, and further dispersed for 3 hours in a sand mill at a rotor rotational speed of 1500 rpm, and then the zirconia beads were removed and planarized. A forming coating solution was obtained.

This flattening forming coating solution was applied onto the colored layer by spin coating. Then, the coating film was baked under conditions of 230 ° C. and 10 minutes under a reduced pressure of 1 × 10 ⁻³ Pa. Next, firing was performed at 230 ° C. for 60 minutes in an oxidizing atmosphere (atmosphere). At this time, the thickness of the flattened portion on the colored layer was 200 nm, and the shape was such that the space between the colored layers was buried, and a shape in which the flattening of the colored layer was promoted was obtained. The step of 1.5 μm was about 0.3 μm.

  Furthermore, in order to eliminate this level | step difference, it grind | polished. Polishing is first performed with lapping sand with No. 800 sandpaper while spraying pure water, then mirror-polished while spraying pure water with a fine particle abrasive of alumina by a rotary polishing machine (made by Speed Fam). (Polishing). As a result, the step of about 0.3 μm was made 0.1 μm or less.

(Formation of auxiliary electrode)
Next, a chromium thin film (thickness 0.2 μm) is formed on the entire surface of the colored layer and the flattened portion by sputtering, and a photosensitive resist is applied on the chromium thin film, mask exposure, development, and etching of the chromium thin film. And an auxiliary electrode was formed. This auxiliary electrode is a strip-like pattern formed at a pitch of 100 μm in parallel with each colored pattern of the colored layer, 5 μm of the width of 15 μm is positioned on each colored pattern, and the remaining portion in the width direction is a flattened portion It is located above, and the width of the terminal portion at the peripheral edge of the transparent substrate is 60 μm.

(Formation of transparent electrode layer)
Next, an indium tin oxide (ITO) electrode film having a thickness of 150 nm is formed on the transparent smoothing layer so as to cover the auxiliary electrode by an ion plating method, and a photosensitive resist is applied on the ITO electrode film, Mask exposure, development, and etching of the ITO electrode film were performed to form a transparent electrode layer. This transparent electrode layer is a band-shaped pattern with a width of 80 μm formed in parallel with each colored pattern of the colored layer, and is located on each colored pattern and overlaps the auxiliary electrode (overlapping width 2.5 μm). there were.

(Formation of insulating layer and partition)
A three-layer thin film of silicon dioxide, titanium nitride, and silicon dioxide is formed by sputtering so as to cover the transparent electrode layer, and the thickness is 0.3 μm (each silicon dioxide thin film: 0.1 μm, titanium nitride: 0.1 μm). An insulating film was formed. Next, a photosensitive resist was applied on the insulating film, mask exposure and development were performed to form a resist pattern. Using this resist pattern as a mask, the exposed insulating film is removed by spray etching using an etching solution (9H ₂ O · 1HF solution or 7H ₂ O · 2HNO ₃ · 1HF solution) at 30 ° C. Formed. This insulating layer has 90 μm × 290 μm rectangular openings with a pitch of 300 μm in the side direction of 290 μm and a pitch of 100 μm in the side direction of 90 μm, and the side of 290 μm of the opening is a colored pattern or a transparent electrode layer. The matrix shape was the same as the extending direction, and the openings were positioned on each colored pattern.

  Next, a partition wall coating material (photograph ZPN1100 manufactured by Nippon Zeon Co., Ltd.) was applied to the entire surface by a spin coating method so as to cover the insulating layer, and prebaked (70 ° C., 30 minutes). Then, it exposed using the photomask for predetermined | prescribed partition, developed with the developing solution (Nippon ZEON Co., Ltd. product ZTMA-100), and then post-baked (100 degreeC, 30 minutes). Thereby, a partition was formed on the matrix-shaped insulating layer (direction parallel to the 90 μm side of the opening). The partition wall had a shape with a height of 10 μm, a lower portion (insulating layer side) width of 15 μm, and an upper portion width of 26 μm.

(Formation of organic EL element layer)
Next, an organic EL element layer composed of a hole injection layer, a light emitting layer, and an electron injection layer was formed by a vacuum deposition method using the partition walls as a mask. That is, first, 4,4 ′, 4 ″ -tris [N- (3-methylphenyl) -N-phenylamino] triphenylamine is 200 nm through a mask having an opening corresponding to the image display region. The partition wall becomes a mask pattern by depositing the film to a thickness and then depositing 4,4′-bis [N- (1-naphthyl) -N-phenylamino] biphenyl to a thickness of 20 nm. The hole injection material passed only between the partition walls, and a hole injection layer was formed on the transparent electrode layer.
Next, in the same manner as described above, a light emitting layer was formed by vapor-depositing a light emitting material to 300 nm using the partition walls as a mask.
Further, tris (8-quinolinol) aluminum was vapor-deposited to a thickness of 20 nm to form an electron injection layer.
The organic EL layer (thickness 500 nm) formed in this manner is present between the partition walls as a strip pattern having a width of about 280 μm, and a dummy organic EL layer having a similar layer structure is also formed on the upper surface of the partition walls. Been formed.

(Formation of back electrode layer)
Next, magnesium and silver are simultaneously vapor-deposited in a region where the partition walls are formed through a mask having a predetermined opening wider than the image display region by a vacuum vapor deposition method (magnesium vapor deposition rate = 1.3 to The film was formed at 1.4 nm / second, silver deposition rate = 0.1 nm / second).
Thereby, the partition wall was used as a mask to form a back electrode layer (thickness 200 nm) made of a magnesium / silver mixture on the organic EL layer. This back electrode layer was present on the organic EL layer as a band-like pattern having a width of 280 μm, and a dummy back electrode layer was also formed on the upper surface of the partition wall.
Thus, an organic EL display device was obtained.

[Comparative example]
An organic EL display device was produced in the same manner as in the example except that in the formation of the flattened portion of the example, polishing was not performed.

[Evaluation]
By applying a voltage of DC 8.5 V to the transparent electrode layer and the back electrode layer of the organic EL display devices of Examples and Comparative Examples at a constant current density of 10 mA / cm ² and continuously driving them, the transparent electrode layer and the back electrode The light emitting layer at a desired portion where the layer intersects was caused to emit light. As a result, compared with the organic EL display device of the comparative example, in the organic EL display device of the example, the transmittance of the color filter can be improved by 3%, and the luminance is improved from 76 cd / m ² to 78 cd / m ² . It was confirmed that there was no problem with the disconnection of the electrodes.

It is a schematic sectional drawing which shows an example of the color filter for organic EL elements of this invention. It is a schematic sectional drawing which shows an example of the organic electroluminescent display apparatus of this invention. It is a schematic sectional drawing which shows the other example of the color filter for organic EL elements of this invention. It is a schematic sectional drawing which shows the other example of the color filter for organic EL elements of this invention. It is a schematic sectional drawing which shows the other example of the color filter for organic EL elements of this invention. It is process drawing which shows an example of the manufacturing method of the color filter for organic EL elements of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Substrate 2 ... Colored layer 3 ... Flattening part 10 ... Color filter for organic EL elements 20 ... Organic EL display device 21 ... Transparent electrode layer 22 ... Organic EL layer 23 ... Back electrode layer

Claims (9)

A substrate, a colored layer formed in a pattern on the substrate, and a flattened portion formed between the colored layers,
The colored layer is a film in which a colorant is dispersed in ultrafine particles, does not contain a resin as a binder, and the planarized portion is a film formed of ultrafine particles. The ultrafine particles have an average particle size of 100 nm or less. Ri Oh in fine particles made of inorganic material,
The color filter for an organic electroluminescent element , wherein the ultrafine particles are indium oxide ultrafine particles or indium ultrafine particles in a state where the surface is oxidized .   The color filter for organic electroluminescence elements according to claim 1, wherein the flattening portion has a light shielding property.   The color filter for organic electroluminescent elements according to claim 1 or 2, wherein the sintering temperature of the ultrafine particles is 350 ° C or lower. The organic electroluminescence device for a color filter according to any one of claims of claims 1 to 3, characterized in that in the range average particle diameter of ultrafine particles of 0.5 to 100 nm. A method for producing a color filter for an organic electroluminescence element, comprising: a substrate; a colored layer formed in a pattern on the substrate; and a flattened portion formed between the colored layers,
The substrate consists of an ultrafine particle dispersion in which ultrafine particles and a colorant are dispersed in a solvent. A colored layer-forming coating solution that does not contain a resin is applied as a binder and baked to form a patterned colored layer. A colored layer forming step,
After the colored layer forming step, a flattening portion forming coating solution comprising an ultrafine particle dispersion in which ultrafine particles are dispersed in a solvent is applied onto the substrate and baked to form a flattened portion. Part forming step;
A surface treatment step of polishing the surfaces of the colored layer and the planarized portion after forming the colored layer and the planarized portion on the substrate, and the ultrafine particles are made of an inorganic material having an average particle size of 100 nm or less. The manufacturing method of the color filter for organic electroluminescent elements characterized by the above-mentioned. In the colored layer forming step and the planarizing portion forming step, firing is performed in an atmosphere in which the ultrafine particles are not oxidized, and then firing in an oxidizing atmosphere, and the atmosphere in which the ultrafine particles are not oxidized is an atmosphere under reduced pressure. The manufacturing method of the color filter for organic electroluminescent elements of Claim 5 characterized by the above-mentioned. A method for producing a color filter for an organic electroluminescence element, comprising: a substrate; a colored layer formed in a pattern on the substrate; and a flattened portion formed between the colored layers,
The substrate consists of an ultrafine particle dispersion in which ultrafine particles and a colorant are dispersed in a solvent. A colored layer-forming coating solution that does not contain a resin is applied as a binder and baked to form a patterned colored layer. A colored layer forming step,
On the substrate, a flattening part forming step of forming a flattening part by applying a coating liquid for forming a flattening part comprising an ultrafine particle dispersion in which ultrafine particles are dispersed in a solvent, and baking the coating liquid;
A surface treatment step of polishing the surfaces of the colored layer and the planarized portion after forming the colored layer and the planarized portion on the substrate;
The ultrafine particles are fine particles made of an inorganic material having an average particle size of 100 nm or less,
In the colored layer forming step and the planarizing portion forming step, firing is performed in an atmosphere in which the ultrafine particles are not oxidized, and then firing in an oxidizing atmosphere, and the atmosphere in which the ultrafine particles are not oxidized is an atmosphere under reduced pressure. manufacturing method of organic color filters for electroluminescent device you wherein a is. The method for producing a color filter for an organic electroluminescent element according to any one of claims 5 to 7, wherein the solvent has a boiling point of 120 ° C or higher. A color filter for organic electroluminescent elements according to any one of claims 1 to 4, a transparent electrode layer formed on the color filter for organic electroluminescent elements, and on the transparent electrode layer An organic electroluminescence display device comprising: an organic electroluminescence layer formed and including at least a light emitting layer; and a back electrode layer formed on the organic electroluminescence layer.

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