JP4982992B2 - Coating liquid for color filter, substrate for organic electroluminescence element, and production method thereof - Google Patents

Description

  The present invention relates to a coating solution for a color filter that is suitably used for forming a colored layer and a light-shielding portion in, for example, an organic electroluminescence display device, and an organic electroluminescence element substrate.

  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.

  What is important in putting an organic EL element into practical use as a light-emitting element in an image display device is that the organic EL element has a fine display function and long-term stability. However, some organic EL elements have a drawback that when they are driven for a certain period, the light emission characteristics such as current-luminance characteristics are remarkably deteriorated.

  A typical cause of the deterioration of the light emission characteristics is the growth of light emission defect points called dark spots. The growth of the dark spot proceeds not only during energization (during driving) but also during storage, and in an extreme case spreads over the entire light emitting surface. This dark spot is considered to be caused by oxidation or aggregation of the constituent material of the organic layer such as the light emitting layer in the organic EL element due to oxygen or moisture. In addition, a gas generated by decomposition of an organic material or the like contained in a colored layer or the like of the organic EL display device during heating in the manufacturing process of the organic EL display device also causes a dark spot. In general, the colored layer is obtained by dispersing a colorant in a binder resin, and gas is generated when the binder resin is heated and decomposed. In addition, even when the light shielding portion in the organic EL display device is a resin film containing a black colorant, gas may be generated due to decomposition or the like of the resin constituting the resin film.

Therefore, it is known to use a colored layer in which an inorganic pigment is dispersed in low-melting glass (for example, see Patent Document 1). In this method, a paste obtained by kneading a low-melting glass, an inorganic pigment, a binder resin, and a solvent is applied onto a substrate in a pattern, and the binder resin and the solvent are removed by baking to form a colored layer. The colored layer thus obtained has the advantage of being excellent in low degassing properties because it does not contain organic substances.
It is also known to use a colored layer made of an inorganic pigment (see, for example, Patent Document 2). In this method, a paste in which an inorganic pigment, a binder resin, and a solvent are mixed is applied onto a substrate in a pattern, and the binder resin and the solvent are removed by baking to form a colored layer. This colored layer is also excellent in low outgassing properties because it does not contain organic matter.
Furthermore, it is known to use a light shielding part in which an inorganic pigment is dispersed in a low-melting glass. This light-shielding part also has the advantage of being excellent in low outgassing properties, like the colored layer.
However, in order to form such a colored layer and a light-shielding part, it is necessary to bake at about 600 ° C., and the types of colorants used for the colored layer and the light-shielding part are limited. For example, when an organic pigment is used, the organic pigment deteriorates due to high-temperature firing. Moreover, since the heat-resistant temperature of a general resin substrate is lower than the firing temperature, it is difficult to form such a colored layer or a light shielding portion on the resin substrate.

Patent Document 3 proposes forming a colored layer using a metal fine particle dispersion containing metal colloid fine particles dispersed in a dispersion medium. This colored layer is formed by applying the metal fine particle dispersion onto the substrate and baking it, and the average particle size of the metal colloidal fine particles is about 5 to 40 nm. Can be baked and has the advantage of high transparency.
However, in this colored layer, metal colloidal fine particles are used as a colorant, and it is difficult to design a material so as to exhibit a desired spectral spectrum.

  Furthermore, a method of providing a barrier layer has been proposed as a technique for preventing intrusion of moisture, oxygen, and gases such as volatile components of the colored layer from the colored layer into the light emitting layer (see, for example, Patent Document 4). However, the barrier layer is generally formed by a sputtering method, a vacuum deposition method, or the like, and it is technically difficult to obtain a barrier layer free from foreign matters such as particles and pinholes by such a method. For this reason, the barrier layer has insufficient moisture resistance and barrier properties to prevent deterioration of the organic EL element. Therefore, although a method of increasing the barrier property by adopting a thick barrier layer is employed, there is a problem that the cost becomes very high.

JP 2000-304915 A JP 2001-174620 A JP 2004-51997 A JP 2002-117976 A

  The present invention has been made in view of the above problems, and is a color filter coating solution for forming a colored layer and a light-shielding portion with less gas generation, and a good image free from defects such as dark spots. The main object is to provide an organic EL element substrate and an organic EL display device capable of display.

  In order to achieve the above object, the present invention provides a color filter coating solution comprising an ultrafine particle dispersion in which ultrafine particles and a colorant are dispersed in a solvent.

By using the color filter coating liquid of the present invention, a colored layer composed of ultrafine particles and a colorant and a light-shielding portion can be formed. Therefore, a colored layer that does not contain a binder resin and is excellent in low degassing properties. And a light shielding part can be obtained. Therefore, the color filter coating liquid of the present invention is suitable for forming a colored layer and a light-shielding portion in an organic EL display device having a member weak against degassing components.
In addition, when a colored layer or a light-shielding part is formed by applying and baking the color filter coating liquid of the present invention, the sintering temperature may be made lower than the normal temperature due to the size effect unique to ultrafine particles. Therefore, it is possible to fire at a temperature lower than the heat resistance temperature of a general colored layer. Therefore, it has the advantage that the choice of the coloring agent used for a colored layer is not narrowed.
Furthermore, since the dispersibility of the ultrafine particles is good, the colorant can be dispersed without agglomeration, and a coating solution for a color filter having good dispersion stability can be obtained. For this reason, when a colored layer is formed, the occurrence of concentration quenching or the like can be prevented.

  In the said invention, it is preferable that the sintering temperature of the said ultrafine particle is 350 degrees C or less. This is because, by using ultrafine particles having a sintering temperature in the above range, when a color layer or a light shielding part is formed by applying and baking a color filter coating solution, baking can be performed at a lower temperature.

The ultrafine particles are preferably at least one kind of ultrafine particles 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 light-shielding portion having high transparency and insulation can be formed.
Further, the ultrafine particles are preferably at least one kind of ultrafine particles selected from the group consisting of indium, alkali metal, and alkaline earth metal. 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.

  In the present invention, the average particle size of the ultrafine particles is preferably in the range of 0.5 nm to 100 nm. This is because it is difficult to produce ultrafine particles having an average particle size that is too small, 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, in the present invention, 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 a time when it is dried after application of the color filter coating solution. This is because damage can be avoided.

  The present invention uses the color filter coating solution described above, and the colorant contained in the color filter coating solution is colored in red, green, or blue. A layer forming coating solution is provided. Moreover, the coating liquid for light-shielding parts is provided using the coating liquid for color filters mentioned above, and the colorant contained in the said coating liquid for color filters is a black colorant.

  Since the color layer forming coating solution and the light shielding part forming coating solution of the present invention use the color filter coating liquid, it is possible to form a colored layer and a light shielding part having excellent low degassing properties. . Moreover, when forming a colored layer and a light-shielding part by apply | coating and baking the coating liquid for coloring layer formation and the coating liquid for light-shielding part formation, it can be baked at temperature lower than usual.

  Further, the present invention evaporates the constituents of the ultrafine particles in a gas atmosphere and in the presence of the vapor of the solution containing the colorant and the solvent, and the vapors of the constituents of the ultrafine particles and the vapors of the solution Provided is a method for producing a coating solution for a color filter, which is brought into contact, cooled and collected to obtain an ultrafine particle dispersion in which ultrafine particles and a colorant are dispersed in the solvent.

  According to the present invention, since ultrafine particles are produced by a so-called gas evaporation method, it is possible to obtain ultrafine particles having an average particle size of about 100 nm or less, a narrow particle size distribution, and good dispersibility. Further, the colorant can be dispersed without agglomeration by the ultrafine particles. Therefore, a color filter coating solution having good dispersion stability can be produced.

  Furthermore, the present invention provides a substrate for an organic EL element, comprising a substrate and a colored layer formed in a pattern on the substrate and having a colorant dispersed in ultrafine particles.

  The colored layer in the present invention is obtained by dispersing a colorant in ultrafine particles and does not contain a binder resin, and thus has excellent low degassing properties. Therefore, when the organic EL element substrate 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. Further, 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, when forming a colored layer by applying and baking 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, due to the size effect peculiar to ultrafine particles, The sintering temperature can be lowered, and the colored layer can be fired at a temperature lower than the heat resistance temperature.

  In the said invention, the planarization layer which consists of a film | membrane formed with the ultrafine particle may be formed on the said colored layer. When a flattening layer is formed by applying a flattening layer-forming coating solution comprising an ultrafine particle dispersion in which ultrafine particles are dispersed in a solvent on the colored layer, the flattening comprising an ultrafine particle dispersion is performed. This is because the layer-forming coating solution is very excellent in fluidity, and therefore can easily flow positively into the gaps between the colored layers and improve flatness. Moreover, it can also be set as the planarization layer excellent in low degassing property.

  Also provided is a substrate for an organic EL element comprising a substrate and a light-shielding portion formed in a pattern on the substrate and having a black colorant dispersed in ultrafine particles.

  Since the light-shielding part in the present invention is excellent in low degassing property like the above colored layer, the occurrence of dark spots is suppressed when the organic EL element substrate of the present invention is used in an organic EL display device. can do. Further, when forming the light-shielding portion, sintering can be performed at a low temperature due to the size effect peculiar to ultrafine particles, so that deterioration of other members such as a colored layer can be prevented.

In the above invention, 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, the transparency and insulation of the colored layer and the light shielding part can be enhanced.
Moreover, 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, the surface of which 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.

  Furthermore, the average particle size of the ultrafine particles is preferably in the range of 0.5 nm to 100 nm. This is because it is difficult to produce ultrafine particles having an average particle size that is too small, 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.

  Moreover, this invention has a colored layer formation process which apply | coats the above-mentioned colored layer formation coating liquid on a board | substrate, and bakes, and forms a patterned colored layer, The board | substrate for organic EL elements characterized by the above-mentioned A manufacturing method is provided.

  According to the present invention, since the colored layer forming coating solution is used, a colored layer having excellent low degassing properties can be formed, and an organic EL element substrate in which dark spots are hardly generated can be manufactured. . Further, due to the size effect peculiar to ultrafine particles, firing can be performed at a temperature lower than the normal sintering temperature, and firing at a temperature lower than the heat resistance temperature of the colored layer becomes possible.

  Furthermore, the present invention has a light-shielding part forming step of forming a light-shielding part in the form of a pattern by applying the above-described coating solution for forming a light-shielding part on a substrate and baking it. A manufacturing method is provided.

  According to the present invention, since the light shielding part forming coating solution is used, a light shielding part having excellent low degassing property can be formed, and an organic EL element substrate in which dark spots are hardly generated can be manufactured. . In addition, the sintering effect can be lowered by the size effect peculiar to ultrafine particles, and firing at a temperature lower than the heat resistant temperature of the colored layer or the like is possible.

  In the said invention, you may bake in the atmosphere which the said ultrafine particle does not oxidize, and may bake in an oxidizing atmosphere after that. This is because the sintering of the ultrafine particles can be sufficiently advanced to form a dense colored layer and a light shielding portion.

  The present invention also provides an organic EL element substrate described above, a transparent electrode layer formed on the organic EL element substrate, an organic EL layer formed on the transparent electrode layer and including at least a light emitting layer, An organic EL display device comprising a back electrode layer formed on an organic EL layer.

  Since the organic EL display device of the present invention uses the above-described organic EL element substrate, it is possible to suppress the occurrence of defects such as dark spots and to display a good image. Further, 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 form a colored layer and a light-shielding portion having excellent low degassing properties by using a color filter coating liquid comprising an ultrafine particle dispersion in which ultrafine particles and a colorant are dispersed in a solvent. Therefore, in the organic EL display device, it is possible to suppress the occurrence of dark spots and to obtain an effect that a good image display can be obtained.

  Hereinafter, the color filter coating liquid of the present invention, the coloring layer forming coating liquid and the light shielding part forming coating liquid using the same, and the method for producing the color filter coating liquid will be described in detail. Further, the organic EL element substrate, the manufacturing method thereof, and the organic EL display device will be described in detail.

A. First, the color filter coating solution of the present invention will be described.
The color filter coating liquid of the present invention is characterized by comprising an ultrafine particle dispersion in which ultrafine particles and a colorant are dispersed in a solvent.

The ultrafine particle dispersion in the present invention is a solution in which ultrafine particles are dispersed individually and uniformly, and aggregation of ultrafine particles does not occur. 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, when a colored layer or a light-shielding portion is formed using the color filter coating liquid of the present invention, since the ultrafine particles play a role like a conventional binder resin, there is no need to use a binder resin, and low A colored layer and a light shielding part having excellent degassing properties can be obtained. Therefore, the color filter coating liquid of the present invention is suitable for forming a colored layer and a light-shielding portion in an organic EL display device having a member weak against degassing components.
In addition, when a colored layer or a light shielding part is formed by applying and baking the color filter coating liquid of the present invention, the sintering temperature can be lowered by the size effect peculiar to ultrafine particles. Firing at a temperature lower than the heat resistant temperature of the colored layer is possible. Therefore, it has the advantage that the choice of the coloring agent used for a colored layer spreads.
Furthermore, since the average particle diameter 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. Therefore, by using the color filter coating liquid of the present invention, a colored layer having high transparency and excellent color characteristics can be formed.
Hereinafter, each component of the color filter coating solution will be described.

1. Ultrafine particles 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. 2000-121437 and 2005-81501.

  The ultrafine particles used in the present invention are preferably those having insulating properties. This is because, in general, the colored layer and the light shielding portion are required to have insulating properties. Moreover, when forming a colored layer, it is preferable that ultrafine particles have transparency further. This is because the colored layer is required to have transparency. 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 light-shielding portion having high insulation and a colored layer having high transparency and insulation can be formed. In addition, when a colored layer or a light-shielding portion is formed by applying and firing the color filter coating solution of the present invention, the sintering temperature can be lowered by using ultrafine particles of indium oxide. Because it can. Further, when ultrafine particles of silicon oxide, silicon nitride, and silicon oxynitride are used, a colored layer and a light-shielding portion having good adhesion to a substrate or the like can be formed.

  In addition, as the ultrafine particles, metal ultrafine particles 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 a colored layer or a light shielding portion.

The ultrafine particles preferably have a sintering temperature of 350 ° C. or lower. This is because by using ultrafine particles having a sintering temperature in the above range, the firing temperature at the time of forming the colored layer or the light shielding portion can be further 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. A TG-DTA apparatus (TG 8120) manufactured by Rigaku is used for the measurement of the sintering temperature.

  Further, 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.

Further, the average particle diameter of the ultrafine particles is only required to be able to lower the sintering temperature, specifically, 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 peculiar to ultrafine particles cannot be expected.
Here, the average particle diameter is generally used to indicate the particle size of the particles. In the present invention, 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 laser method is a method of measuring an average particle size, a particle size distribution, and the like by dispersing particles in a solvent, thinning the scattered light obtained by applying a laser beam to the dispersion solvent, and calculating. .

  The concentration of the ultrafine particles in the ultrafine particle dispersion may be appropriately selected so that it can be easily applied and a desired film thickness can be obtained. Specifically, it is preferably in the range of 1 to 50 wt%. More preferably, it is 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 and the light shielding portion may be impaired.

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

  The gas evaporation method is a method in which a metal is evaporated in a gas atmosphere in a gas phase in which a solvent vapor coexists, and the evaporated metal is condensed into uniform ultrafine particles and dispersed in a solvent to obtain a dispersion. is there. In this gas evaporation method, ultrafine metal particles having a uniform particle size can be obtained. In order to prepare an ultrafine particle dispersion using the ultrafine metal particles obtained by the 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. Note that a method for producing ultrafine particles by the gas evaporation method is detailed in Japanese Patent No. 2651537 and Japanese Patent Application Laid-Open No. 2005-183054.

In the liquid phase reduction method, a reducing raw material that is a metal-containing organic compound can be used as a raw material for producing ultrafine particles. The liquid phase reduction method is one type of chemical reduction method, and the chemical reduction method is a method of preparing an ultrafine particle dispersion by a chemical reaction using a reducing agent. In the case of the fine particles produced by this chemical reduction method, the particle size can be arbitrarily adjusted. In the chemical reduction method, first, the raw material is thermally decomposed at a predetermined temperature in a state where a dispersant is added to the raw material, or ultrafine metal particles are formed using a reducing agent such as hydrogen or sodium borohydride. generate. Next, almost all of the generated ultrafine metal particles are recovered in an independently dispersed state. By replacing the obtained dispersion with a solvent used for the ultrafine particle dispersion, a desired ultrafine particle dispersion can be obtained. The obtained ultrafine particle dispersion maintains a stable dispersion state even if it is concentrated by heating in vacuum.
In the case of producing an ultrafine particle dispersion using ultrafine metal particles obtained by a chemical reduction method such as a liquid phase reduction method, a dispersant may be added after the ultrafine metal particles are produced by chemical reduction. A dispersant may be added. In the latter case, an ultrafine particle dispersion having better dispersion stability can be obtained.
A metal-containing organic compound is used as a raw material for producing metal ultrafine particles, and examples thereof include bishexafluoroacetylacetonate copper, bisacetylacetonate nickel, and bisacetylacetonate cobalt.
Note that Japanese Patent Application Laid-Open No. 2005-81501 and Japanese Patent Application Laid-Open No. 2002-121606 can be referred to for a method for producing ultrafine particles by a liquid phase reduction method.

2. Colorant As the colorant used in the present invention, a pigment can be used, which may be an organic pigment or an inorganic pigment. Here, the amount of the colorant contained in the colored layer or the like is smaller than the content of the ultrafine particles. Further, when a colored layer or the like is formed using the color filter coating liquid of the present invention, the organic pigment is included in the ultrafine particles made of the inorganic material in the layer and is generated from the organic pigment. Since ultrafine particles block the gas, it is difficult for the gas to be released from within the layer. Therefore, even when an organic pigment is used, it is considered that it does not cause a large dark spot.

When the colored layer is formed using the color filter coating liquid of the present invention, a colorant colored in red, green, or blue is used. The colorant is not particularly limited as long as it is colored in red, green, or blue, and may be colored by using one kind of pigment alone, or may be colored by combining two or more kinds.
Examples of the colorant used for forming the red colored layer include perylene pigments, lake pigments, azo pigments, quinacridone pigments, anthraquinone pigments, anthracene pigments, isoindoline pigments, and the like. . These pigments may be used alone or in combination of two or more.
Examples of the colorant used for forming the green colored layer include halogen multi-substituted phthalocyanine pigments, halogen multi-substituted copper phthalocyanine pigments, triphenylmethane basic dyes, isoindoline pigments, and isoindolinone pigments. Etc. These pigments may be used alone or in combination of two or more.
Examples of the colorant used for forming the blue colored layer include copper phthalocyanine pigments, indanthrene pigments, indophenol pigments, cyanine pigments, and dioxazine pigments. These pigments may be used alone or in combination of two or more.
The content of the colorant varies depending on whether it is an organic pigment or an inorganic pigment, but is usually about 5 to 50% by weight based on the solid content in the color filter coating solution. If the content of these colorants is less than the above range, sufficient color correction cannot be performed when a colored layer is formed, and if the content of the colorant is more than the above range, the dispersibility of the colorant This is because there is a possibility that concentration quenching occurs.

Moreover, when forming a light shielding part using the coating liquid for color filters of this invention, a black coloring agent is used as a coloring agent. 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 10 to 80 weight% with respect to solid content in the coating liquid for color filters. When the content of the black colorant is less than the above range, the light shielding property is lowered when the light shielding portion is formed, and when the content of the black colorant is more than the above range, the dispersibility of the black colorant is deteriorated. Because there are cases.

Furthermore, when forming a light-shielding part, at least 2 types selected from the group which consists of a blue colorant, a red colorant, and a yellow colorant can also be mixed and used as a black colorant. 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 it is an organic pigment or an inorganic pigment, but is 5 to 50 based on the solid content in the color filter coating liquid. It can be about wt%. This is because when the content of these colorants is less than the above range and the light shielding part is formed, the light shielding property is lowered, and when the content is more than the above range, concentration quenching may occur.

3. Solvent The solvent used in the present invention is appropriately selected depending on the ultrafine particles to be used. For example, alcohols such as methanol, ethanol, propanol, isopropyl alcohol, butanol, hexanol, heptanol, octanol, decanol, cyclohexanol, terpineol, etc. Glycols 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; dioxane and tetrahydrofuran Ethers such as N; N-dimethylformamide; acid amides such as benzene, toluene, xylene, trimethylbenzene, dodecylbenzene, etc. Aromatic hydrocarbons: Long-chain alkanes such as hexane, heptane, octane, nonane, decane, undecane, dodecane, tridecane, tetradecane, pentadecane, hexadecane, octadecane, nonadecane, eicosane, trimethylpentane, etc .; cyclohexane, cycloheptane, cyclooctane, etc. And cyclic alkanes. 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.

  Examples of the solvent used when preparing an ultrafine particle dispersion using indium oxide ultrafine particles include alcohols such as methanol, ethanol, isopropanol, and butanol; acetone, methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone, isophorone, 4- Ketones such as hydroxy-4methyl-2pentanone; hydrocarbons such as toluene, xylene, hexane and cyclohexane; amides such as N, N-dimethylformamide and N, N-dimethylacetamide; methyl carbitol and butyl carbitol Alkyl ethers such as sulfoxides such as dimethyl sulfoxide; and the like. These solvents can be used alone or in combination of two or more.

Furthermore, the solvent is preferably a solvent that evaporates during drying and baking when forming the colored layer and the light shielding portion. 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 easily evaporates at the time of drying, so that the ultrafine particles are likely to aggregate and a uniform colored layer and a light shielding part 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.

  In addition, when the color filter coating liquid of the present invention is applied by a discharge method, compatibility with the discharge head (for example, no corrosion or dissolution), and aggregation or clogging of ultrafine particles in the discharge head In view of the above, it is preferable to select an appropriate solvent.

  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.

4). Dispersant In the present invention, the color filter coating solution may contain a dispersant. This is because the dispersing agent adheres so as to surround the periphery of the ultrafine particles, so that the dispersibility of the ultrafine particles can be improved. As a result, the dispersibility of the colorant is also improved.
The dispersant used in the present invention is not particularly limited, and examples thereof include alkylamines, carboxylic acid amides, aminocarboxylates and the like.

As the alkylamine, an alkylamine having a main skeleton having 4 to 20 carbon atoms is preferable, and an alkylamine having a main skeleton having 8 to 18 carbon atoms is more preferable from the viewpoints of stability and handling properties. This is because if the number of carbon atoms in the main chain of the alkylamine is shorter than 4, the basicity of the amine is too strong and the ultrafine particles may be corroded. Further, if the number of carbon atoms in the main chain of the alkylamine is longer than 20, when the concentration of the ultrafine particle dispersion is increased, the viscosity of the ultrafine particle dispersion may increase and the handling property may be inferior. Moreover, although all series of alkylamines work effectively as a dispersant, primary alkylamines are preferably used from the viewpoints of stability and handling properties.
Examples of such alkylamines include primary amines such as butylamine, octylamine, dodecylamine, hexadodecylamine, octadecylamine, cocoamine, tallowamine, hydrogenated tallowamine, oleylamine, laurylamine, stearylamine; dicocoamine, dihydrogen Secondary amines such as modified tallowamine and distearylamine; tertiary amines such as dodecyldimethylamine, didodecylmonomethylamine, tetradecyldimethylamine, octadecyldimethylamine, cocodimethylamine, dodecyltetradecyldimethylamine, and trioctylamine Etc. In addition, diamines such as naphthalenediamine, stearylpropylenediamine, octamethylenediamine, and nonanediamine can also be used.

  Specific examples of carboxylic acid amides and aminocarboxylates include stearic acid amide, palmitic acid amide, lauric acid lauryl amide, oleic acid amide, oleic acid diethanolamide, oleic acid lauryl amide, stearanilide, oleylaminoethylglycine, etc. There is.

  One or more of these alkylamines, carboxylic acid amides, and aminocarboxylates can be used, thereby acting as a stable dispersant.

  The alkylamine content is preferably about 0.1 to 10% by weight, more preferably 0.2 to 7% by weight, based on the weight of the ultrafine particles. This is because if the content of the alkylamine is less than the above range, the ultrafine particles are not dispersed in an independent state, but aggregates thereof are generated, resulting in poor dispersion stability. Moreover, it is because there exists a possibility that the viscosity of an ultrafine particle dispersion may become high when content of an alkylamine exceeds the said range.

5. Others The method for producing the color filter coating liquid of the present invention is not particularly limited. For example, ultrafine particles are prepared by a gas evaporation method, and the resulting ultrafine particles are dispersed in a solvent. The colorant may be added later, and when the ultrafine particles are produced by the gas evaporation method, the ultrafine particles and the colorant are dispersed in the solvent using a solution containing the colorant and the solvent. A dispersion may be obtained. The latter method will be described in detail in the section of “D. Manufacturing method of color filter coating solution” described later, and will not be described here.

  Moreover, the coating liquid for color filters of this invention can be used as ink for inkjet. In the coating liquid for color filter of the present invention, ultrafine particles are dispersed in an independent state, aggregation of ultrafine particles and colorant is not generated, fluidity is maintained, and ink characteristics are excellent.

In the present invention, the viscosity of the ultrafine particle dispersion is preferably in the range of 0.1 to 100 cP at 20 ° C., and more preferably in the range of 0.1 to 10 cP. It is because a flat colored layer and a light shielding part can be formed if the viscosity is in the above range.
The surface tension of the ultrafine particle dispersion is preferably 25 to 80 mN / m, and more preferably 30 to 60 mN / m. This is because, if the surface tension is in the above range, the ink characteristics for using the color filter coating liquid of the present invention as an inkjet ink can be sufficiently satisfied.

B. Next, the colored layer forming coating solution of the present invention will be described.
The color layer forming coating liquid of the present invention uses the above-described color filter coating liquid, and the colorant contained in the color filter coating liquid is colored in red, green, or blue. It is characterized by being. That is, the coating liquid for forming a colored layer of the present invention comprises an ultrafine particle dispersion in which ultrafine particles and a colorant that is colored in red, green, or blue are dispersed in a solvent.

According to the present invention, since the color filter coating solution is used, it is possible to form a colored layer having excellent low degassing properties. Moreover, when forming a colored layer by apply | coating and baking the coating liquid for colored layer formation, a calcination temperature can be made low.
In addition, since it described in the item of the said coating liquid for color filters about the other point of the coating liquid for colored layer formation, description here is abbreviate | omitted.

C. Next, the light shielding part forming coating solution of the present invention will be described.
The light shielding part forming coating liquid of the present invention is characterized in that the color filter coating liquid described above is used and the colorant contained in the color filter coating liquid is a black colorant. That is, the light shielding part forming coating liquid of the present invention comprises an ultrafine particle dispersion in which ultrafine particles and a black colorant are dispersed in a solvent.

According to the present invention, since the color filter coating solution is used, it is possible to form a light-shielding portion having excellent low degassing properties. Moreover, when forming a light-shielding part by apply | coating and baking the coating liquid for light-shielding part formation, it can bake at temperature lower than usual.
In addition, since the other point of the light shielding part forming coating liquid was described in the section of the color filter coating liquid, description thereof is omitted here.

D. Next, a method for producing a color filter coating solution of the present invention will be described.
The method for producing a coating solution for a color filter according to the present invention comprises evaporating constituents of ultrafine particles in a gas atmosphere and in the presence of vapor of a solution containing a colorant and a solvent. Then, the vapor of the above solution is brought into contact with the vapor of the solution and collected by cooling to obtain an ultrafine particle dispersion in which ultrafine particles and a colorant are dispersed in the solvent.

In the present invention, for example, in a vacuum chamber and in an atmosphere where the pressure of an inert gas such as helium is 10 Torr or less, the metal that is a component of the ultrafine particles is evaporated, and the vapor of the evaporated metal or the like is evaporated. When collecting by cooling, the vapor of the solution containing the colorant and solvent is introduced into the vacuum chamber, and the surface is brought into contact with the vapor of the solution at the stage where the metal, etc. grows, and the resulting primary particles are independent. In addition, it is possible to obtain a fine particle independent dispersion which is uniformly dispersed in a solvent in a colloidal form. If necessary, a vapor such as a metal may be brought into contact with the reaction gas.
In this way, the present invention produces ultrafine particles using the gas evaporation method, and ultrafine particles with uniform particle sizes can be obtained.

  The component of the ultrafine particles in the present invention may be the component of the ultrafine particles described in the above section “A. Color filter coating liquid”, and usually the metal constituting the ultrafine particles, or silicon or boron Etc. For example, by evaporating metal or silicon or boron, ultrafine particles of metal, or ultrafine particles of oxide, nitride, oxynitride such as metal, silicon, or boron can be obtained.

  The gas atmosphere used in the present invention is appropriately selected according to the type of target ultrafine particles. For example, when producing ultrafine metal particles, an inert gas such as helium is preferably used. For example, when producing ultrafine particles of inorganic oxide, inorganic nitride, or inorganic oxynitride, oxygen, carbon dioxide, nitrogen, air, or the like is used as a reaction gas. At this time, the gas pressure is preferably about 10 Torr or less.

In addition, when the solvent used for condensing the vapor of the constituent component of the ultrafine particles is not suitable as a solvent for the color filter coating solution, the solvent in the dispersion obtained by the gas evaporation method is used. What is necessary is just to substitute with the solvent suitable for the coating liquid for color filters.
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.
The ultrafine particles, the colorant, the solvent, and the dispersant are the same as those described in the above section “A. Color filter coating solution”, and thus the description thereof is omitted here.

  As for the gas evaporation method, reference can be made to Japanese Patent No. 2561537, Japanese Patent Application Laid-Open No. 2000-112437, Japanese Patent Application Laid-Open No. 2005-183054, and the like.

  In another aspect of the method for producing a color filter coating liquid according to the present invention, the metal ultra-fine particles are dispersed in the solvent by evaporating the metal in a gas atmosphere and in the presence of the vapor of the first solvent. A first step of obtaining a dispersed liquid, a second solvent, which is a low molecular weight polar solvent, is added to the dispersion liquid, a colorant is further added, the ultrafine metal particles and the colorant are precipitated, and the supernatant liquid is obtained. It has the 2nd process of removing the said 1st solvent substantially by removing, and obtaining a deposit, and the 3rd process of adding the 3rd solvent to the above-mentioned sediment, and obtaining ultrafine particle dispersion. Is.

According to this aspect, the first step of obtaining a dispersion by bringing the vapor of the metal into contact with the vapor of the first solvent by the gas evaporation method, and adding the second solvent, which is a low molecular weight polar solvent, to the dispersion A second step of precipitating the ultrafine metal particles and extracting and removing the first solvent; and adding a third solvent to the precipitate thus obtained to replace the solvent to obtain an ultrafine particle dispersion. By performing these steps, a color filter coating solution comprising an ultrafine particle dispersion can be produced.
The ultrafine metal particles can be produced by a low-vacuum gas evaporation method. According to this method, ultrafine metal particles having a particle size of 100 nm or less can be produced. Since these metal ultrafine particles are used as raw materials and solvent replacement is performed to make them suitable for use as color filter coating liquids, particularly ink jet inks, the metal ultrafine particles are individually independent. Thus, it is possible to obtain a color filter coating liquid suitable for inkjet ink, which is uniformly dispersed and maintains a fluid state. That is, the ultrafine particle dispersion produced in this way has excellent ink characteristics as an inkjet ink.
In addition, the solvent used for the ultrafine metal particles used in the gas evaporation method and the solvent used for the color filter coating solution are different (for example, the same, but the purity is different). Although it may be necessary, in this embodiment, the first solvent and the third solvent can be different, which is advantageous.

In this aspect, first, in the first step, when the metal is evaporated in the vacuum chamber and in an atmosphere in which the pressure of the inert gas such as He is 10 Torr or less, and the evaporated metal vapor is cooled and collected. In addition, the vapor of one or more kinds of the first solvent is introduced into the vacuum chamber, and the surface of the metal is brought into contact with the first solvent vapor at the stage of the grain growth of the metal. A dispersion liquid colloidally dispersed in the first solvent is obtained, and the first solvent is removed in the next second step. The reason for removing the first solvent in this way is to remove by-products generated by the modification of the coexisting first solvent when the metal vapor evaporated in the first step is condensed, and depending on the application. This is because an ultrafine particle dispersion liquid dispersed in a low-boiling solvent, water, an alcohol-based solvent or the like that is difficult to use in the first step is produced.
Next, in the second step, the second solvent, which is a low molecular weight polar solvent, is added to the dispersion obtained in the first step to precipitate the ultrafine metal particles contained in the dispersion, and the supernatant is The first solvent used in the first step is removed by removing by a stationary method or decantation. This second step is repeated a plurality of times to substantially remove the first solvent.
Then, in the third step, a new third solvent is added to the sediment obtained in the second step, and solvent replacement is performed to obtain an ultrafine particle dispersion. Thereby, an ultrafine particle dispersion in which ultrafine particles of metal having a particle size of 100 nm or less are dispersed in an independent state is obtained.

  In this embodiment, a dispersant may be added in the first step or the third step, or in the first step and the third step. Thereby, the dispersed state can be further stabilized. When a dispersant is added in the third step, a dispersant that does not dissolve in the solvent used in the first step can also be used. The dispersant is the same as that described in the section “A. Color filter coating solution”.

  Since the first solvent is a solvent for producing ultrafine metal particles used in the gas evaporation method, it has a relatively high boiling point so that it can be easily liquefied when cooling and collecting ultrafine metal particles. Preferably there is. The first solvent is appropriately selected depending on the constituent elements of the ultrafine metal particles to be used. For example, alcohols having 5 or more carbon atoms such as terpineol, citronol, geraniol, and phenethyl alcohol, benzyl acetate, and stearic acid. Mention may be made of organic esters such as ethyl, methyl oleate, ethyl phenylacetate and glycerides.

  The second solvent is a low molecular weight polar solvent that can precipitate and remove the first solvent by precipitating the ultrafine metal particles contained in the dispersion obtained in the first step. For example, acetone may be used.

  Further, as the third solvent, for example, a non-polar hydrocarbon having 6 to 20 carbon atoms in the main chain, water, an alcohol having 15 or less carbon atoms, and the like that is liquid at normal temperature can be used. In the case of nonpolar hydrocarbons, if the number of carbon atoms is less than 6, drying may be too early and handling properties may be inferior. If the number of carbon atoms exceeds 20, the viscosity of the ultrafine particle dispersion will increase, or firing will occur. Carbon may remain later. In the case of alcohol, if the carbon number exceeds 15, the viscosity of the ultrafine particle dispersion may increase, or carbon may remain after firing. Specifically, the solvents described in the section “A. Color filter coating solution” can be used.

E. Next, the organic EL element substrate of the present invention will be described. The substrate for organic EL elements of the present invention can be divided into two embodiments. The first embodiment has a substrate and a colored layer in which a colorant is dispersed in ultrafine particles. The second embodiment has a substrate and a light shielding part in which a black colorant is dispersed in ultrafine particles. In the following, each embodiment will be described separately.

1. First Embodiment A first embodiment of a substrate for an organic EL device of the present invention comprises a substrate and a colored layer formed in a pattern on the substrate and having a colorant dispersed in ultrafine particles. It is what.

The organic EL element substrate of the present embodiment will be described with reference to the drawings.
FIG. 1 is a schematic cross-sectional view showing an example of the organic EL element substrate of the present embodiment. As shown in FIG. 1, the organic EL element substrate 10 has a colored layer 2 formed on a substrate 1.

The colored layer is obtained by dispersing a colorant in ultrafine particles, and unlike the conventional one in which a colorant is dispersed in a binder resin, it contains almost no organic matter that is a source of degassed components. Since it does not contain the binder resin, which is the main cause of degassing components, it has excellent low degassing properties. In addition, when an organic pigment is used as the colorant, the organic pigment is contained in the ultrafine particles made of the inorganic material in the colored layer, and the ultrafine particles block the gas generated from the organic pigment. Gas is less likely to be released from within the layer. Therefore, in this embodiment, generation | occurrence | production of a dark spot can be suppressed and a favorable image display is attained when the organic EL element substrate of this embodiment is used for an organic EL display device.
Further, since the generation of dark spots can be suppressed, it is not necessary to provide a thick barrier layer as in the prior art, so that cost reduction and yield improvement can be achieved.

  Furthermore, when the colored layer is formed by applying and baking the above-described color filter coating solution, the sintering temperature is lowered as compared with the normal sintering temperature due to the size effect unique to the ultrafine particles. It is possible to perform firing at a temperature lower than the heat resistance temperature of a general colored layer. 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.

Further, when the thickness of the colored layer is relatively thin, concentration quenching is likely to occur due to aggregation of the colorant. In this embodiment, the dispersibility of the ultrafine particles is good, and the colorant is formed by the ultrafine particles in the colored layer. Can be dispersed without agglomerating, so that the thickness of the colored layer can be reduced without deteriorating the color characteristics.
Hereinafter, each structure of the organic EL element substrate will be described.

(1) Colored layer The colored layer used in this embodiment is obtained by dispersing a colorant in ultrafine particles. The colored layer is a layer that corrects the color of light from the light emitting layer or enhances the color purity when an organic EL display device is formed using the organic EL element substrate of the present embodiment. 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.

  The ultrafine particles used in this embodiment preferably have insulating properties, and more preferably have transparency. This is because the colored layer is required to have insulation and transparency. Examples of such ultrafine particles include inorganic oxides, inorganic nitrides, and inorganic oxynitride ultrafine particles. The ultrafine particles of inorganic oxide, inorganic nitride, and inorganic oxynitride are the same as those described in the above section “A. Coating liquid for color filter”, and the description thereof is omitted here. To do.

  Moreover, as the ultrafine particles, ultrafine particles of metal whose surface is oxidized can also be used. Specifically, the metals include In, Al, Ti, Ta, Zn, Sn, Y, Ge, Pb, Zr, alkali metals (Li, Na, K), alkaline earth metals (Mg, Ca, Sr, Ba). ) And the like. 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.

Furthermore, metal ultrafine particles can be used as the ultrafine particles. That is, the ultrafine particles may have electrical conductivity. The metal ultrafine particles are the same as those described in the above section “A. Color filter coating solution”, and thus the description thereof is omitted here.
When the colored layer contains ultrafine particles of metal, it has conductivity, so that it is preferable that an insulating planarizing layer is formed on the colored layer as described later. This is because when the organic EL element substrate of the present invention is used in an organic EL display device, a transparent electrode layer or the like is formed on the colored layer.

The sintering temperature, melting point, and average particle size of the ultrafine particles are the same as those described in the above section “A. Color filter coating solution”, and thus the description thereof is omitted here.
Here, the average particle diameter of the ultrafine particles can be confirmed by a scanning electron microscope (SEM) observation photograph (high magnification).

Further, the colorant is the same as that described in the above-mentioned section “A. Color filter coating solution”, and therefore the description thereof is omitted here.
The colorant varies depending on whether it is an organic pigment or an inorganic pigment, but is usually contained in an amount of about 5 to 50% by weight in each colored pattern. This is because when the content of the colorant is less than the above range, sufficient color correction cannot be performed, and when the content of the colorant is more than the above range, concentration quenching may occur.

  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 1 μm to 3 μm. Within range. When the thickness of the colored layer is too thick, the permeability may be lowered, or peeling from the substrate or the like may occur. Also, if the thickness of the colored layer is too thick, the level difference due to the colored pattern becomes too large, and even if a flattening layer described later is formed on the colored layer, it becomes difficult to flatten and a short circuit between the electrodes may occur. There is. Furthermore, when the level difference due to the colored pattern is large, the planarization layer must be thickened for planarization, and it becomes difficult to form an electrode at the end of the planarization layer, the transmittance is reduced, The cost may increase. In the present invention, since the dispersibility of the colorant can be improved by the ultrafine particles, the concentration of the colorant can be relatively increased, and the thickness of the colored layer can be relatively reduced. On the other hand, if the color layer is too thin, there is a possibility that sufficient color correction cannot be performed.

In this embodiment, it is preferable to form the colored layer by applying and baking the above-described colored layer forming coating solution. 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.
In addition, since the formation method of a colored layer is described in the section of "F. Manufacturing method of substrate for organic EL element" mentioned later, description here is abbreviate | omitted.

(2) Light Shielding Part In this embodiment, for example, as shown in FIG. 2, the light shielding part 3 may be formed between the colored patterns 2R, 2G, and 2B. This is because by providing a light-shielding portion such as a black matrix, it is possible to improve contrast when an organic EL display device is formed using the organic EL element substrate of this embodiment. Moreover, the unevenness | corrugation by a coloring pattern can be planarized by making the thickness of a light-shielding part the same or the same level as the thickness of a colored layer. Thereby, when the organic EL element substrate of this embodiment is used in an organic EL display device, it is possible to prevent a short circuit between the electrodes.

  In addition, although not shown, when a color conversion layer described later is formed, a light shielding portion may be formed between each color conversion pattern and each coloring pattern. In this case, the unevenness | corrugation by a color conversion pattern and a coloring pattern can be planarized by making the thickness of a light-shielding part into the same or the same grade as the thickness which combined the color conversion layer and the coloring layer. Thereby, when the organic EL element substrate of this embodiment is used in an organic EL display device, it is possible to prevent a short circuit between the electrodes.

Examples of the light shielding portion include a resin film containing a black colorant, or a metal thin film such as chromium, chromium oxide, and chromium nitride. The metal thin film may be a CrO _x film (x is an arbitrary number) and a laminate of two Cr films, and a CrO _x film (x is an arbitrary number) with a reduced reflectance. , CrN _y film (y is an arbitrary number) and three layers of Cr film may be laminated.
Moreover, it can also be set as the light-shielding part which disperse | distributed the black coloring agent in the ultrafine particle. The ultrafine particles and the black colorant are the same as those described in the above section “A. Color filter coating solution”, and thus the description thereof is omitted here.
Among these, the light shielding part which consists of a metal thin film, and the light shielding part which disperse | distributed the black coloring agent in an ultrafine particle have the advantage that it is excellent in low degassing property. On the other hand, the resin film containing the black colorant only needs to have a light-shielding property and can be sufficiently heat-treated, so that the degassed component can be removed when the light-shielding part is formed.

  As a method for forming the light shielding portion, for example, a photolithography method or the like can be used when a resin film containing a black colorant is formed. In the case of forming a metal thin film, for example, a method of forming a thin film by a sputtering method, a vacuum vapor deposition method, or the like and forming it in a pattern using a photolithography method is used. Moreover, a metal thin film can also be formed using an electroless plating method or a printing method. Furthermore, when forming the film | membrane which disperse | distributed the black coloring agent in an ultrafine particle, the method of apply | coating and baking the coating liquid for light-shielding part formation mentioned above can be used.

  The thickness of the light shielding portion can be about 0.5 μm to 2 μm for a resin film containing a black colorant, and about 0.2 μm to 0.4 μm for a metal thin film. The thickness of the film in which the black colorant is dispersed in the ultrafine particles can be about 0.5 μm to 2 μm.

(3) Flattening layer In this embodiment, the flattening layer 6 may be formed so as to fill the irregularities due to the colored patterns 2R, 2G, and 2B as shown in FIGS. 3 and 4, for example. Moreover, when the color conversion layer is formed, the planarization layer may be formed so that the unevenness | corrugation by each coloring pattern and each color conversion pattern may be filled. The flattening layer is provided for the purpose of flattening the irregularities on the surface of the colored layer or the color conversion layer, for the purpose of protecting the colored layer or the color conversion layer, or for the purpose of filling the level difference due to the patterned colored layer or the color conversion layer. It is done. Furthermore, when the colored layer or the color conversion layer has conductivity, there is also an object of forming a planarizing layer having insulating properties to insulate it from the transparent electrode layer or the like.

  The material for forming the planarization layer used in this embodiment is not particularly limited, and for example, a resin can be used. The resin is preferably a resin having 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, Examples thereof include 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).

The planarizing layer used in this embodiment is preferably a film formed of ultrafine particles. It is because it can be set as the planarization layer excellent in low degassing property similarly to a colored layer, and generation | occurrence | production of a dark spot can be suppressed. In addition, when a flattening layer is formed by applying a flattening layer forming coating solution made of an ultrafine particle dispersion in which ultrafine particles are dispersed in a solvent on the colored layer, a flat surface made of an ultrafine particle dispersion is used. Since the coating liquid for forming a chemical layer is very excellent in fluidity, it is easy to actively flow into the gaps between the colored layers, and the flatness can be improved.
As the ultrafine particles used in the planarization layer, the same ultrafine particles as those used in the colored layer can be used.

  In addition, the thickness of the planarizing layer may be any thickness as long as it is possible to planarize a step due to a patterned colored layer or a color conversion layer. For example, the thickness (height) of the colored layer, or, if a color conversion layer is formed, the planarizing layer should be the same or approximately the same as the combined thickness (height) of the colored layer and the color conversion layer. It may be formed. Further, for example, a flattening layer is formed so as to be thicker than the thickness (height) of the color layer and the color conversion layer when the color layer is formed. May be. Specifically, the thickness of the planarizing layer formed on the colored layer can be set within a range of 0.1 μm to 10 μm, and preferably within a range of 0.2 μm to 4 μm.

  In this embodiment, it is preferable to form the planarization layer by applying and baking a planarization layer-forming coating solution comprising an ultrafine particle dispersion in which ultrafine particles are dispersed in a solvent. That is, the planarizing layer is preferably a coating film formed of ultrafine particles. By forming the planarizing 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. Thereby, deterioration of the colorant and the fluorescent material due to heat can be prevented.

(4) Substrate The substrate used in the present embodiment is preferably transparent in order to extract light from the substrate side when an organic EL display device is formed using the organic EL element substrate 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 organic EL element substrate of the present invention. For example, a transparent glass substrate that has been coated or stepped Is mentioned.

  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.

(5) Color conversion layer In this embodiment, the color conversion layer may be formed on the colored layer. 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 the organic EL element substrate of the present embodiment is used to form an organic EL display device. There is no particular limitation as long as the light can be red, green, or blue.

  The color conversion layer may be composed of color conversion patterns 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.

In the present embodiment, the color conversion layer is preferably one in which a fluorescent material is dispersed in ultrafine particles. It is because it can be set as the color conversion layer excellent in low degassing property similarly to the said colored layer, and generation | occurrence | production of a dark spot can be suppressed.
As the ultrafine particles used in the color conversion layer, the same ultrafine particles as those used in the colored layer can be used.

  The fluorescent material used in this embodiment is particularly limited as long as it absorbs light and emits visible light region fluorescence, and can make incident light red light, green light, or blue light. Is not to be done. As the fluorescent material, 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. 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. In the color conversion layer, the organic fluorescent material is included in the ultrafine particles made of the inorganic material, and the ultrafine particles block the gas generated from the organic fluorescent material. It becomes difficult to be released. Therefore, in the color conversion layer in which the fluorescent material is dispersed in the ultrafine particles, not only dark spots but also pixel reduction and luminance reduction of the light emitting layer can be suppressed.

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 and emit red region fluorescence include rhodamine B, rhodamine 6G, rhodamine 3B, rhodamine 101, rhodamine 110, sulforhodamine, basic violet 11, and basic red 2. Rhodamine dyes, cyanine dyes, pyridine dyes such as 1-ethyl-2- [4- (p-dimethylaminophenyl) -1,3-butadienyl] -pyridinium perchlorate (pyridine 1), or oxazine dyes Etc.
Various dyes (direct dyes, acid dyes, basic dyes, disperse dyes, etc.) can also be used if they are fluorescent.

Examples of fluorescent dyes that absorb light in the blue or blue-green region and emit fluorescence in the green region include 3- (2′-benzothiazolyl) -7-diethylaminocoumarin (coumarin 6) and 3- (2′-benzoimidazolyl). -7-N, N-diethylaminocoumarin (coumarin 7), 3- (2'-N-methylbenzimidazolyl) -7-N, N-diethylaminocoumarin (coumarin 30), 2,3,5,6-1H, 4H -Coumarin-based dyes such as tetrahydro-8-trifluoromethylquinolidine (9,9a, 1-gh) coumarin (coumarin 153), or basic yellow 51 which is a coumarin dye-based dye, and further, solvent yellow 11 and solvent yellow 116 And naphthalimide dyes.
Various dyes (direct dyes, acid dyes, basic dyes, disperse dyes, etc.) can also be used if they are fluorescent.

Further, the fluorescent dye is previously added to, for example, polymethacrylic acid ester, 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. A fluorescent pigment may be obtained by kneading into a pigment.
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 said fluorescent material is 0.01-5 weight% with respect to each color conversion pattern on the basis of the weight of the color conversion pattern, More preferably, 0.1-5 weight% is contained. 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. In the present invention, since the dispersibility of the fluorescent material can be improved by the ultrafine particles, concentration quenching hardly occurs, and the content of the fluorescent material can be relatively increased.

  Further, the film thickness of the color conversion layer is not particularly limited as long as the wavelength can be converted, but specifically, it can be set within a range of 500 nm to 50 μm, preferably It is in the range of 1 μm to 10 μm. If the film thickness of the color conversion layer is too thick, there is a possibility that the transparency is lowered or peeling from the substrate or the like occurs. Also, if the color conversion layer is too thick, the step due to the color conversion pattern becomes too large, and even if a flattening layer described later is formed on the color conversion layer, it becomes difficult to flatten, and a short circuit between the electrodes may occur. Can occur. Furthermore, when the level difference due to the color conversion pattern is large, the planarization layer must be thickened for planarization, and it becomes difficult to form electrodes at the edge of the planarization layer, or the transmittance decreases. The cost may increase. In the present invention, since the dispersibility of the fluorescent material can be improved by the ultrafine particles as described above, the concentration of the fluorescent material can be relatively increased, and the thickness of the color conversion layer can be relatively reduced. Can do. On the other hand, if the film thickness of the color conversion layer is too thin, there is a possibility that sufficient wavelength conversion cannot be performed.

  In this embodiment, it is preferable to form the color conversion layer by applying and baking a color conversion layer-forming coating solution comprising an ultrafine particle dispersion in which ultrafine particles and a fluorescent material are dispersed or dissolved in a solvent. 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 below the heat resistant temperature of the color conversion layer due to the size effect unique to the ultrafine particles.

Further, when a transparent pattern is formed instead of the color conversion pattern, the transparent pattern is preferably formed of ultrafine particles. This is because the transparent pattern formed of ultrafine particles is excellent in low degassing properties. The ultrafine particles described above can be used as the ultrafine particles used in the transparent pattern.
Furthermore, the transparent pattern is preferably formed by applying and baking an ultrafine particle dispersion in which ultrafine particles are dispersed in a solvent. That is, the transparent pattern is preferably a coating film formed of ultrafine particles. This is because the sintering effect can be lowered below the heat resistance temperature of the color conversion layer due to the size effect unique to the ultrafine particles.

2. Second Embodiment A second embodiment of the substrate for an organic EL element of the present invention comprises a substrate and a light shielding portion formed in a pattern on the substrate and having a black colorant dispersed in ultrafine particles. It is a feature.

The organic EL element substrate of the present embodiment will be described with reference to the drawings.
FIG. 5 is a schematic cross-sectional view showing an example of the organic EL element substrate of the present embodiment. As shown in FIG. 5, the organic EL element substrate 10 has a light shielding portion 3 formed on a substrate 1.

The light-shielding part is made by dispersing a black colorant in ultrafine particles, and unlike the conventional ones in which a black colorant is dispersed in a binder resin, it hardly contains organic substances that are the source of degassing components. In particular, since it does not contain a binder resin, which is the main cause of degassing components, it has excellent low degassing properties. Therefore, in this embodiment, generation | occurrence | production of a dark spot can be suppressed and a favorable image display is attained when the organic EL element substrate of this embodiment is used for an organic EL display device.
Further, since the generation of dark spots can be suppressed, it is not necessary to provide a thick barrier layer as in the prior art, so that cost reduction and yield improvement can be achieved.

  Furthermore, when the light shielding part is formed by applying and baking the above-described coating liquid for forming the light shielding part, the sintering temperature is lower than the normal sintering temperature due to the size effect unique to the ultrafine particles. And firing at a temperature lower than the heat resistance temperature of the substrate or the colored layer becomes possible.

In the present embodiment, for example, as shown in FIG. 2, a colored layer 2 may be formed between the patterned light shielding portions 3. Further, a color conversion layer may be formed between the patterned light-shielding portions 3. Further, in the case where a colored layer or a color conversion layer is formed, a planarizing layer may be formed so as to fill the unevenness due to the patterned colored layer and the color conversion layer and to cover the light shielding portion.
Hereinafter, each structure of the organic EL element substrate will be described. Since the substrate, the color conversion layer, and the planarization layer are the same as those described in the first embodiment, description thereof is omitted here.

(1) Light-shielding part The light-shielding part used in this embodiment is obtained by dispersing a black colorant in ultrafine particles. By providing a light blocking portion such as a black matrix, the contrast can be improved when an organic EL display device is formed using the organic EL element substrate of this embodiment.

  The ultrafine particles used in this embodiment may be anything that has insulating properties. Examples of such ultrafine particles include inorganic oxides, inorganic nitrides, and inorganic oxynitride ultrafine particles. The ultrafine particles of inorganic oxide, inorganic nitride, and inorganic oxynitride are the same as those described in the above section “A. Coating liquid for color filter”, and the description thereof is omitted here. To do.

  Moreover, as the ultrafine particles, ultrafine particles of metal whose surface is oxidized can also be used. Specifically, the metals include In, Al, Ti, Ta, Zn, Sn, Y, Ge, Pb, Zr, alkali metals (Li, Na, K), alkaline earth metals (Mg, Ca, Sr, Ba). ) And the like. 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.

The sintering temperature, melting point, and average particle size of the ultrafine particles are the same as those described in the above section “A. Color filter coating solution”, and thus the description thereof is omitted here.
Here, the average particle diameter can be confirmed by a scanning electron microscope (SEM) observation photograph (high magnification).

Further, the black colorant is the same as that described in the above-mentioned section “A. Color filter coating solution”, and thus the description thereof is omitted here.
When the black colorant is a titanium pigment or the like, it is usually contained at about 10 to 80% by weight. Moreover, when using a blue colorant, a red colorant, and a yellow colorant as a black colorant, although it changes with whether it is an organic pigment or an inorganic pigment, it is normally contained by about 5 to 50 weight%. 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.

  Specifically, the thickness of the light shielding part can be set within a range of 500 nm to 5 μm, and preferably within a range of 1 μm to 3 μm. In the case where a colored layer or a color conversion layer is formed, the thickness of the light shielding portion may be the same as or approximately the same as the thickness of the colored layer or the color conversion layer. Thereby, the unevenness | corrugation by a coloring pattern or a color conversion pattern can be planarized, and when the organic EL element substrate of this embodiment is used for an organic EL display device, it is possible to prevent a short circuit between the electrodes. Become.

  In this embodiment, it is preferable to form the light shielding part by applying and baking the above-described light shielding part forming coating solution. 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 a temperature lower than the heat resistance temperature of the substrate or the colored layer by the size effect peculiar to the ultrafine particles. In addition, since the formation method of a light-shielding part is described in the section of "F. Manufacturing method of substrate for organic EL element" mentioned later, description here is abbreviate | omitted.

(2) Colored layer In this embodiment, the colored layer 2 may be formed between the pattern-shaped light-shielding parts 3, as illustrated in FIG. The colored layer 2 is generally composed of a red colored pattern 2R, a green colored pattern 2G, and a blue colored pattern 2B.

  In this embodiment, it is preferable that the colored layer has a colorant dispersed in ultrafine particles. It is because it can be set as the colored layer excellent in low degassing property similarly to the said light-shielding part, and generation | occurrence | production of a dark spot can be suppressed. In addition, about the colored layer which disperse | distributed the coloring agent in the ultrafine particle, since it is the same as that of the colored layer described in the said 1st embodiment, description here is abbreviate | omitted.

F. Next, a method for producing an organic EL element substrate of the present invention will be described. The method for producing an organic EL device substrate of the present invention can be divided into two embodiments. A 1st aspect has a colored layer formation process which apply | coats and bakes the coating liquid for colored layer formation mentioned above on a board | substrate, and forms a patterned colored layer. Moreover, a 2nd aspect has a light-shielding part formation process which apply | coats and bakes the coating liquid for light-shielding part formation mentioned above on a board | substrate, and forms a pattern-shaped light-shielding part. Hereinafter, the description will be made separately for each aspect.

1. 1st aspect The 1st aspect of the manufacturing method of the board | substrate for organic EL elements of this invention apply | coats the coating liquid for colored layer formation mentioned above on a board | substrate, and baked, and forms the colored layer of a pattern shape. It has a layer forming step.

  FIG. 6 is a process diagram showing an example of a method for producing an organic EL element substrate according to this embodiment. In this embodiment, first, a red colored layer forming coating solution 12R made of an ultrafine particle dispersion in which ultrafine particles and a red colorant are dispersed in a solvent is applied onto the substrate 1 and dried (FIG. 6). (A)). Next, a green colored layer forming coating solution 12G made of an ultrafine particle dispersion in which ultrafine particles and a green colorant are dispersed in a solvent is applied onto the substrate 1 by an ink jet method and dried (FIG. 6B). ). Furthermore, a blue colored layer forming coating solution 12B made of an ultrafine particle dispersion in which ultrafine particles and a blue colorant are dispersed in a solvent is applied onto the substrate 1 by an ink jet method and dried (FIG. 6C). . Next, these are fired (FIG. 6D). In this way, the colored layer 2 composed of the red colored pattern 2R, the green colored pattern 2G, and the blue colored pattern 2B is formed (FIG. 6E).

According to this aspect, since the colored layer forming coating solution is used, a colored layer having excellent low degassing property can be formed, and an organic EL element substrate in which dark spots are hardly generated can be obtained. Further, in this embodiment, the ultrafine particles are densely sintered at a temperature much lower than the general sintering temperature due to the size effect peculiar to the ultrafine particles, so that the colored layer can be fired at a temperature lower than the heat resistant temperature.
Hereinafter, each process of the manufacturing method of the board | substrate for organic EL elements is demonstrated.

(1) Colored layer forming step In the colored layer forming step in this embodiment, 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 is applied on a substrate and baked. And forming a patterned colored layer.
In addition, since it described in the term of the said "A. coating liquid for color filters" and "B. coating liquid for colored layer formation" about the coating liquid for colored layer formation, description here is abbreviate | omitted.

  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 this embodiment, the temperature 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 this aspect, as a patterning method of the colored layer, for example, a resist method, a discharge method, a printing method, or the like can be used.

In the resist method, for example, as shown in FIG. 7, a resist 15 is applied on the colored layer 2 obtained by baking the coating film 13 (FIGS. 7A to 7C), and then through a mask 16. Exposure (FIG. 7 (d)) and development (FIG. 7 (e)). Next, by performing acid etching and resist stripping, the colored layer 2 can be formed in a pattern (FIG. 7F).
Moreover, when using a resist method, a resist may be apply | coated on the coating film after drying, and a resist may be apply | coated on the film | membrane after baking. 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 these, at least one ultrafine particle 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 this embodiment has a relatively low viscosity, so that 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 “A. Color filter coating solution”.
Moreover, among the above-mentioned, since the manufacturing process is simple, the inkjet method is preferably used.

(2) Light-shielding part formation process In this aspect, you may perform the light-shielding part formation process which forms a pattern-shaped light-shielding part on a board | substrate before the said colored layer formation process. The light-shielding part forming step is a process of applying a light-shielding part-forming coating solution comprising an ultrafine particle dispersion in which ultrafine particles and a black colorant are dispersed in a solvent and baking to form a patterned light-shielding part. It is preferable. This is because, as in the case of the colored layer forming step, it is possible to form a light shielding portion that is excellent in low outgassing properties.
The light shielding part forming coating liquid is described in the above-mentioned sections “A. Color filter coating liquid” and “C. Light shielding part forming coating liquid”, and thus the description thereof is omitted here. Moreover, since the coating method, baking method, patterning method, etc. of the coating solution for forming the light shielding part are the same as those described in the section of the colored layer forming step, description thereof is omitted here.

(3) Planarization layer formation process In this aspect, you may perform the planarization layer formation process which forms a planarization layer on a colored layer after the said colored layer formation process. Moreover, when performing the said color conversion layer formation process, a planarization layer is formed on a color conversion layer. The flattening layer forming step is preferably a step of forming a flattening layer by applying and baking a coating liquid for forming a flattening layer comprising an ultrafine particle dispersion in which ultrafine particles are dispersed in a solvent. This is because, as in the case of the colored layer forming step, it is possible to form a planarizing layer having excellent low degassing properties.
The ultrafine particles, the solvent, and the like are the same as those described in the section “A. Color filter coating solution”, and the coating method and firing method of the planarizing layer forming coating solution are as follows. Since it is the same as that described in the section of the colored layer forming step, description thereof is omitted here.

  In addition, when a desired film thickness cannot be obtained only by applying a coating liquid for forming a flattening layer made of an ultrafine particle dispersion in which ultrafine particles are dispersed in a solvent, the coating liquid for forming a flattening layer is used. After coating, drying, and firing, the planarization layer can be made thicker by further coating, drying, and firing the planarization layer forming coating solution.

2. Second Aspect In the second aspect of the method for producing an organic EL element substrate of the present invention, the above-described light shielding part forming coating solution is applied onto a substrate and baked to form a light shielding part having a pattern shape. It has a part formation process, It is characterized by the above-mentioned.

In this embodiment, for example, the light-shielding portion can be formed in a pattern by applying a coating solution for forming the light-shielding portion on the substrate by an inkjet method, drying, and baking.
According to this aspect, since an ultrafine particle dispersion in which ultrafine particles and a black colorant are dispersed in a solvent is used, a light-shielding portion having excellent low degassing properties can be formed, and an organic EL element that hardly generates dark spots. A substrate can be obtained. In addition, in this embodiment, due to the size effect unique to the ultrafine particles, the ultrafine particles are densely sintered at a temperature much lower than the general sintering temperature, so that the substrate and the colored layer can be fired at a temperature lower than the heat resistance temperature. is there.

  The light shielding part forming coating liquid is the same as that described in the above-mentioned sections “A. Color filter coating liquid” and “C. Light shielding part forming coating liquid”. The coating liquid coating method, baking method, and patterning method are the same as those described in the section of the colored layer forming step of the first aspect, and a description thereof is omitted here.

  In this aspect, a colored layer forming step of forming a colored layer in the opening of the light shielding portion on the substrate may be performed after the light shielding portion forming step. This colored layer forming step is preferably a step of applying the above-described colored layer forming coating solution and baking it to form a patterned colored layer. In addition, about such a colored layer formation process, since it is the same as that of what was described in the said 1st aspect, description here is abbreviate | omitted.

  In this embodiment, the color conversion layer forming step and the planarizing layer forming step may be performed as in the first embodiment.

G. 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 an organic EL element substrate described above, a transparent electrode layer formed on the organic EL element substrate, and an organic EL formed on the transparent electrode layer and including at least a light emitting layer. It has a layer and a back electrode layer formed on the organic EL layer.

  FIG. 8 shows an example of the organic EL display device of the present invention. As shown in FIG. 8, the organic EL display device 20 includes an organic EL element substrate 10 described above, a transparent electrode layer 21 formed on the organic EL element substrate 10, and a pattern on the transparent electrode layer 21. The organic EL layer 22 is formed in a shape, 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 substrate 10 is formed by forming a patterned colored layer 2 on the substrate 1 and forming a light shielding portion 3 between the patterned colored layers 2.

According to the present invention, since the organic EL element substrate described above is used, the occurrence of defects such as dark spots can be suppressed, and an organic EL display device capable of good image display can be obtained. Further, since the organic EL element substrate does not easily generate dark spots, it is not necessary to provide a thick barrier layer as in the prior art, and cost reduction and yield improvement can be achieved.
Hereinafter, each configuration of such an organic EL display device will be described. The organic EL element substrate is the same as that described in the section “E. Organic EL Element Substrate”, and a description thereof will be omitted.

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 black matrix)
As a transparent substrate, soda glass (Sn face polished product manufactured by Central Glass Co., Ltd.) having a size of 150 mm × 150 mm and a thickness of 0.7 mm was prepared. After cleaning this transparent substrate according to a conventional method, a thin film (thickness 0.2 μm) of oxynitride composite chromium is formed on the entire surface of one side of the transparent substrate by sputtering, and a photosensitive resist is applied onto the composite chromium thin film. Then, mask exposure, development, and etching of the composite chromium thin film were performed to form a black matrix having 84 μm × 284 μm rectangular openings in a matrix at a pitch of 100 μm.

(Formation of colored layer)
When producing In particles by gas evaporation using high frequency induction heating under the condition of helium gas pressure of 0.5 Torr, 20: 1 (capacity ratio) of α-terpineol and dodecylamine is used as In particles in the production process. 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 mixture of green pigment CI Pigment Green 36 and CI Pigment Yellow 83 (100: 10) was further dispersed in the ultrafine particle dispersion at a concentration of 30 wt% in terms of solid content, did. This green colored layer coating solution is applied by spin coating on a transparent substrate on which a black matrix is formed, and then the coating is applied under conditions of 230 ° C. and 10 min under a reduced pressure of 1 × 10 ⁻³ Pa. Baked. Next, firing was performed in an oxidizing atmosphere (atmosphere) at 230 ° C. for 60 minutes. At this time, the thickness of the green colored layer 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 pattern the green colored layer. This green colored layer was a strip-like pattern with a width of 90 μm located at a predetermined position covering the opening of the black matrix.

In the same manner, a mixture of red pigment CI Pigment Red 177 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, and the coating for the red colored layer is performed. A working solution was used. This red colored layer coating solution is applied by spin coating onto a transparent substrate on which a black matrix is formed, and then the coating is applied under conditions of 230 ° C. and 10 min under a reduced pressure of 1 × 10 ⁻³ Pa. Baked. Next, firing was performed in an oxidizing atmosphere (atmosphere) at 230 ° C. for 60 minutes. At this time, the film thickness of the red colored layer was 1.5 μm.
Next, a photosensitive resist was applied onto the red colored layer by spin coating, and drying, mask exposure, development, and etching of the red colored layer were performed to pattern the red colored layer. This red-red colored layer was a band-like pattern having a width of 90 μm located at a predetermined position covering the opening of the black matrix.

In the same manner, a mixture of blue pigment CI pigment blue 15: 3 and CI pigment violet 23 (100: 5) is dispersed in an ultrafine particle dispersion at a concentration of 30 wt% in terms of solid content to obtain a blue colored layer. The coating liquid was used. This blue colored layer coating solution is applied onto a transparent substrate on which a black matrix is formed by a spin coating method, and then the coating is applied under conditions of 230 ° C. and 10 min under a reduced pressure of 1 × 10 ⁻³ Pa. Baked. Next, firing was performed in an oxidizing atmosphere (atmosphere) at 230 ° C. for 60 minutes. The film thickness of the blue colored layer at this time was 1.5 μm.
Next, a photosensitive resist was applied onto the blue colored layer by spin coating, and the blue colored layer was patterned by drying, mask exposure, development, and etching of the blue colored layer. This blue colored layer was a strip-like pattern with a width of 90 μm located at a predetermined position covering the opening of the black matrix.

(Formation of planarization layer)
When producing In particles by gas evaporation using high frequency induction heating under the condition of helium gas pressure of 0.5 Torr, 20: 1 (capacity ratio) of α-terpineol and dodecylamine is used as In particles in the production process. 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.
This ultrafine particle dispersion 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 in an oxidizing atmosphere (atmosphere) at 230 ° C. for 60 minutes. Thereby, the planarization layer was formed so that the level | step difference by a colored layer might be filled up. At this time, the thickness of the planarizing layer on the colored layer was 200 nm, the level difference due to the colored layer was about 1.5 μm to 0.5 μm, and the level difference due to the colored layer was leveled by the leveling layer.

(Formation of transparent electrode layer)
Next, after forming an SiO ₂ film with a thickness of 50 nm as an underlayer by ion plating on the planarizing layer, an indium tin oxide (ITO) film with a thickness of 150 nm is formed, and a photosensitive layer is formed on the ITO film. The resist was applied, mask exposure, development, and etching of the ITO film were performed to form a transparent electrode layer. This transparent electrode layer was a strip-shaped pattern with a width of 80 μm formed on the planarizing layer so as to run on the colored layer from the transparent substrate, and was located on each colored layer.

(Formation of auxiliary electrode)
Next, a chromium thin film (thickness 0.2 μm) is formed by sputtering on the entire surface of the planarizing layer so as to cover the transparent electrode layer, a photosensitive resist is applied on the chromium thin film, mask exposure, development, The auxiliary electrode was formed by etching the chromium thin film. This auxiliary electrode is a belt-like pattern formed on the transparent electrode layer so as to run on the colored layer from the transparent substrate. The auxiliary electrode has a width of 14 μm and is located on the light shielding portion of the black matrix. The terminal portion at the peripheral edge of the material had a width of 60 μm.

(Formation of insulating layer and partition)
Using a coating solution for insulating layer in which norbornene-based resin (ARTON manufactured by JSR Corporation) with an average molecular weight of approximately 100,000 is diluted with toluene, the flat electrode layer is covered with a spin coating method so as to cover the transparent electrode layer. Then, baking (100 ° C., 30 minutes) was performed to form an insulating film (thickness 1 μm). Next, a photosensitive resist was applied on the insulating film, mask exposure, development, and etching of the insulating film were performed to form an insulating layer. This insulating layer was a strip-like pattern (width 20 μm) intersecting the transparent electrode layer at a right angle, and was located on the black matrix.

  Next, a partition wall coating (photoresist 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, the partition was formed on the insulating layer. 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 layer)
Next, an organic element layer composed of a hole injection layer, a blue light emitting layer, and an electron injection layer was formed by vacuum deposition using the partition walls as a mask. That is, first, 4,4 ′, 4 ″ -tris [N- (3-methylphenyl) -N-phenylamino] triphenylamine is passed through a photomask having an opening corresponding to the image display area. By vapor-depositing to a thickness of 200 nm, and then forming a film by vapor-depositing 4,4′-bis [N- (1-naphthyl) -N-phenylamino] biphenyl to a thickness of 20 nm, the partition walls are mask patterns. As a result, the hole injection material passed only between the partition walls to form the hole injection layer on the transparent electrode layer. Similarly, 4,4′-bis (2,2-diphenylvinyl) biphenyl was evaporated to 50 nm to form a blue light emitting layer. Thereafter, tris (8-quinolinol) aluminum was deposited to a thickness of 20 nm to form an electron injection layer. The organic element layer thus formed exists between the partition walls as a band-shaped pattern having a width of 280 μm, and a dummy organic EL layer having a similar layer structure was formed on the upper surface of the partition walls.

(Formation of back electrode layer)
Next, magnesium and silver are simultaneously deposited on the region where the partition is formed through a photomask having a predetermined opening wider than the image display region by vacuum deposition (magnesium 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, and a back electrode layer (thickness 200 nm) made of a magnesium / silver mixture was formed on the organic EL layer. This back electrode layer exists 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 Example except that the colored layer was formed as follows.

(Formation of colored layer)
Mixing 13 parts by weight of an alkali-soluble negative resist, 7 parts by weight of a mixture of green pigment CI Pigment Green 36 and CI Pigment Yellow 83 (100: 10), and 80 parts by weight of ethyl cellosolve acetate for a green colored layer A coating solution was prepared. This green colored layer coating solution was applied onto a transparent substrate on which a black matrix was formed by spin coating, and pre-baked (80 ° C., 30 minutes). Next, patterning was performed by photolithography, and post-baking (100 ° C., 30 minutes) was performed. As a result, a green colored layer (thickness: 1.5 μm) having a band shape (width: 90 μm) was formed.

  Furthermore, 13 parts by weight of an alkali-soluble negative resist, 7 parts by weight of a mixture of blue pigment CI pigment blue 15: 3 and CI pigment violet 23 (100: 5) and 80 parts by weight of ethyl cellosolve acetate were mixed, A blue colored layer coating solution was prepared. This blue colored layer coating solution was applied onto a transparent substrate on which a black matrix was formed by spin coating, and pre-baked (80 ° C., 30 minutes). Next, patterning was performed by photolithography, and post-baking (100 ° C., 30 minutes) was performed. Thus, a blue colored layer (thickness: 1.5 μm) having a band shape (width: 90 μm) was formed.

  Further, 13 parts by weight of an alkali-soluble negative resist, 7 parts by weight of a mixture of red pigments CI Pigment Red 177 and CI Pigment Yellow 83 (100: 20), and 80 parts by weight of ethyl cellosolve acetate are mixed and colored red. A layer coating solution was prepared. This red colored layer coating solution was applied onto a transparent substrate on which a black matrix was formed by spin coating, and prebaked (80 ° C., 30 minutes). Next, patterning was performed by photolithography, and post-baking (100 ° C., 30 minutes) was performed. As a result, a red colored layer (thickness: 1.5 μm) having a strip shape (width: 90 μm) was formed.

[Evaluation]
A transparent electrode layer and a back electrode layer are formed by applying a voltage of DC 8.5 V to the transparent electrode layer and the back electrode layer of the organic EL display device of the example and the comparative example at a constant current density of 10 mA / cm 2 and continuously driving. The blue light-emitting layer at a desired portion where and intersected was caused to emit light. Then, after color correction with the colored layer, CIE chromaticity coordinates (JIS Z 8701) were measured for emission of each color observed on the opposite surface side of the transparent substrate.
In the organic EL display device of the example, red light emission of x = 0.64 and y = 0.35 in CIE chromaticity coordinates, green light emission of x = 0.25 and y = 0.65 in CIE chromaticity coordinates, CIE Blue light emission of x = 0.14 and y = 0.18 was confirmed in the chromaticity coordinates, and a three primary color image display with high luminance (82 cd / m ² ) and high color purity was possible.
On the other hand, in the organic EL display device of the comparative example, red emission with x = 0.64 and y = 0.35 in CIE chromaticity coordinates, and green emission with x = 0.25 and y = 0.65 in CIE chromaticity coordinates. The blue light emission of x = 0.15 and y = 0.20 was confirmed in the CIE chromaticity coordinates, and although the three primary colors could be displayed, the luminance was as low as 68 cd / m ² .

It is a schematic sectional drawing which shows an example of the board | substrate for organic EL elements of this invention. It is a schematic sectional drawing which shows the other example of the board | substrate for organic EL elements of this invention. It is a schematic sectional drawing which shows the other example of the board | substrate for organic EL elements of this invention. It is a schematic sectional drawing which shows the other example of the board | substrate for organic EL elements of this invention. It is a schematic sectional drawing which shows the other example of the board | substrate for organic EL elements of this invention. It is process drawing which shows an example of the manufacturing method of the board | substrate for organic EL elements of this invention. It is process drawing which shows the other example of the manufacturing method of the board | substrate 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.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Board | substrate 2 ... Colored layer 3 ... Light-shielding part 6 ... Planarizing layer 10 ... Substrate for organic EL element 12 ... Coating liquid for colored layer formation 20 ... Organic EL display device 21 ... Transparent electrode layer 22 ... Organic EL layer 23 ... Back electrode layer

Claims (19)

A coating solution for a color filter, comprising: an ultrafine particle composed of an inorganic material ; and a colorant composed of a pigment, which is dispersed in a solvent and includes an ultrafine particle dispersion containing no binder resin.   The color filter coating solution according to claim 1, wherein the sintering temperature of the ultrafine particles is 350 ° C or lower.   The color filter according to claim 1 or 2, wherein the ultrafine particles are at least one ultrafine particle selected from the group consisting of indium oxide, silicon oxide, silicon nitride, and silicon oxynitride. Coating liquid.   The color filter coating according to claim 1 or 2, wherein the ultrafine particles are at least one kind of ultrafine particles selected from the group consisting of indium, alkali metal, and alkaline earth metal. liquid.   The color filter coating solution according to any one of claims 1 to 4, wherein an average particle size of the ultrafine particles is in a range of 0.5 nm to 100 nm.   The color filter coating solution according to any one of claims 1 to 5, wherein the solvent has a boiling point of 120 ° C or higher.   The color filter coating liquid according to any one of claims 1 to 6, wherein the colorant contained in the color filter coating liquid is red, green, or blue. A coating solution for forming a colored layer, characterized by being colored.   The color filter coating liquid according to any one of claims 1 to 6, wherein the colorant contained in the color filter coating liquid is a black colorant. Part forming coating solution. The components of the ultrafine particles are evaporated in a gas atmosphere and in the presence of a vapor of a solution containing a colorant and a solvent, and the vapor of the components of the ultrafine particles and the vapor of the solution are brought into contact with each other to cool and capture. A method for producing a coating solution for a color filter, in which ultrafine particles and a colorant are dispersed in the solvent, and an ultrafine particle dispersion containing no binder resin is obtained ,
The method for producing a coating solution for a color filter, wherein the ultrafine particles are made of an inorganic material, and the colorant is made of a pigment . An organic electroluminescence device comprising: a substrate; and a colored layer formed in a pattern on the substrate, in which a colorant composed of a pigment is dispersed in ultrafine particles composed of an inorganic material , and does not contain a binder resin. Substrate.   11. The organic electroluminescent element substrate according to claim 10, wherein a planarizing layer made of a film formed of ultrafine particles is formed on the colored layer. An organic electroluminescence device comprising: a substrate; and a light-shielding portion formed in a pattern on the substrate, wherein a black colorant composed of a pigment is dispersed in ultrafine particles composed of an inorganic material , and does not contain a binder resin. Device substrate.   The ultra-fine particle is at least one kind of ultra-fine particle selected from the group consisting of indium oxide, silicon oxide, silicon nitride, and silicon oxynitride. The organic electroluminescent element substrate according to claim.   The ultrafine particles are at least one ultrafine particle selected from the group consisting of indium, alkali metal, and alkaline earth metal, the surface of which is oxidized. The substrate for organic electroluminescence elements according to any one of claims 12 to 12.   The substrate for an organic electroluminescent element according to any one of claims 10 to 14, wherein an average particle diameter of the ultrafine particles is in a range of 0.5 nm to 100 nm.   A substrate for an organic electroluminescence device comprising a colored layer forming step of forming a patterned colored layer by applying the coating liquid for forming a colored layer according to claim 7 on a substrate, followed by baking. Manufacturing method.   A substrate for an organic electroluminescence element, comprising: a light shielding part forming step of applying a light shielding part forming coating solution according to claim 8 on a substrate and baking the coating liquid to form a patterned light shielding part. Manufacturing method.   18. The method for manufacturing a substrate for an organic electroluminescence element according to claim 16, wherein the ultrafine particles are baked in an atmosphere in which the ultrafine particles are not oxidized, and then baked in an oxidizing atmosphere.   The organic electroluminescent element substrate according to any one of claims 10 to 15, a transparent electrode layer formed on the organic electroluminescent element substrate, and formed on the transparent electrode layer. An organic electroluminescence display device comprising: an organic electroluminescence layer including at least a light emitting layer; and a back electrode layer formed on the organic electroluminescence layer.

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