JP2007033963A - Color filter - Google Patents

Abstract

PROBLEM TO BE SOLVED: To produce a simple process capable of controlling the scattering intensity of red light, green light, and blue light, being hardly affected by external light, excellent in display quality such as high contrast and high brightness, and the like. The main purpose is to provide a simple color filter.
SOLUTION: The present invention comprises a transparent substrate and fine particles formed on the transparent substrate and having a light scattering action dispersed in the layer, and is composed of a red coloring pattern, a green coloring pattern, and a blue coloring pattern. The color filter is characterized in that the content of the fine particles contained in each of the red color pattern, the green color pattern, and the blue color pattern is different from each other. To achieve.
[Selection] Figure 1

Description

  The present invention relates to a color filter used in a self-luminous display device such as an electroluminescence (hereinafter abbreviated as EL) display device.

  A self-luminous element that emits light by providing a light-emitting layer between electrodes and generating light is not only a display device, but also a flat illumination, a light source for optical fibers, a backlight for liquid crystal displays, a backlight for liquid crystal projectors, etc. Research and development is actively underway for various light sources.

As an example of a basic structure of a conventional self-luminous element, a structure in which a transparent electrode, a light emitting layer, and a back electrode are laminated on a transparent substrate can be exemplified. Usually, a metal electrode having reflection characteristics is used for the back electrode, and among the light emitted from the light emitting layer, the light emitted to the rear side (metal electrode side) of the light emitting layer is reflected by the metal electrode and forward Since it radiates | emits to (transparent electrode side), there exists an advantage that the brightness | luminance of an element improves.
However, since this metal electrode also reflects light incident on the element from the outside, there is a problem that reflection by external light occurs from a region that should not be displayed (non-light emitting), and display contrast is lowered. In particular, in a portable display device used in a bright environment such as outdoors, such reflection of external light becomes a problem.

In order to suppress such a decrease in contrast due to reflection of external light, a circularly polarizing plate is generally provided on the front surface of the transparent substrate (see, for example, Patent Document 1). When a circularly polarizing plate is used, the rotation direction of the circularly polarized light is reversed when the external light is reflected by the metal electrode, so that the reflection of the external light can be efficiently suppressed and a high contrast display can be obtained. .
However, since light emitted from the light-emitting layer in the self-light-emitting element is generally non-polarized light, when a circularly polarizing plate is used to prevent external light reflection, about half of the emitted light is absorbed by the circularly polarizing plate. For this reason, there is a problem that the efficiency of taking out emitted light to the outside is reduced, and the luminance is reduced to half or less.

  Further, in the self-light emitting element, light having an incident angle greater than the critical angle determined by the refractive index of the transparent substrate and the refractive index of the emission medium (for example, air) among the light emitted from the light emitting layer is emitted from the transparent substrate. Since the light is totally reflected at the interface with the medium, confined inside the light emitting layer, and cannot be extracted outside, there is a problem in that the light extraction efficiency decreases.

  As a technique for improving the light extraction efficiency, it has been proposed to provide a light scattering layer with an EL element (see, for example, Patent Documents 2 to 4). In the light emitting device having the above-described configuration, for example, when a light scattering layer is formed between the transparent substrate and the light emitting layer, the light scattering layer also guides light having an incident angle greater than the critical angle to the emission medium (for example, air). Will be. For this reason, the light extraction efficiency can be improved by forming the light scattering layer.

  However, even if the light scattering effect is obtained by the light scattering layer, the light scattering intensity depends on the wavelength, and the light having a shorter wavelength scatters more strongly. It will be bigger than that. As described above, when the red, green, and blue light have different scattering intensities, there is a problem that a color shift occurs depending on the viewing angle.

  In general, it is known that the scattering intensity can be controlled, for example, by adjusting the content of fine particles. Therefore, in order to control the scattering intensity of red light, green light, and blue light, it is considered that the light scattering layer may be patterned by appropriately adjusting the content of fine particles according to each color. However, if the colored layers of each color are patterned and the light scattering layer is also patterned according to each color, there is a problem that the manufacturing process becomes complicated.

Japanese Patent Laid-Open No. 8-322138 JP-A-6-347617 Japanese Patent Laid-Open No. 6-151061 JP 2004-39388 A

  The present invention has been made in view of the above problems, is hardly affected by external light, has excellent display quality such as high contrast and high brightness, and can control the scattering intensity of red light, green light, and blue light. The main object of the present invention is to provide a color filter that can be manufactured by a simple process.

  In order to achieve the above object, the present invention comprises a transparent substrate and fine particles formed on the transparent substrate and having a light scattering action dispersed in the layer, and a red coloring pattern, a green coloring pattern, and a blue coloring. There is provided a color filter comprising a colored layer composed of a pattern, wherein the contents of the fine particles contained in the red colored pattern, the green colored pattern, and the blue colored pattern are different from each other.

  According to the present invention, since the colored layer is a layer in which fine particles having a light scattering action are dispersed, and the colored layer itself exhibits light scattering properties, the color filter of the present invention is used for, for example, an EL display device. In this case, reflection of external light can be suppressed and total reflection of light emission at the interface between the transparent substrate and the emission medium can be suppressed. Moreover, the scattering intensity of red light, green light and blue light is controlled by making the content of the fine particles contained in the red coloring pattern, green coloring pattern and blue coloring pattern constituting the colored layer different. It is possible to prevent color shift depending on the viewing angle. Furthermore, since the red coloring pattern, the green coloring pattern, and the blue coloring pattern are dispersed fine particles, it is not necessary to separately provide a light scattering layer in accordance with red light, green light, and blue light, and simple. A color filter having excellent scattering characteristics and display quality can be obtained in the process.

  In the said invention, it is preferable that content of the microparticles | fine-particles contained in the said blue coloring pattern is less than content of each microparticles | fine-particles contained in the said red coloring pattern and the green coloring pattern. For example, in general, in an EL display device having a light emitting layer that emits white light, white light emitted tends to be a bluish light. However, when the color filter of the present invention is applied to such an EL display device. With the above configuration, it is possible to suppress the color shift by suppressing the scattering of blue light.

  In the said invention, it is preferable that the average particle diameter of the said fine particle exists in the range of 1.0 micrometer-1.6 micrometers. Since the haze value can be increased by setting the average particle size of the fine particles within a predetermined range, when the color filter of the present invention is used in an EL display device, for example, the reflection of external light is suppressed and contrast is increased. This is because the light extraction efficiency can be effectively improved by suppressing the total reflection of light emission at the interface between the transparent substrate and the output medium.

  The color filter of the present invention preferably has a haze value in the range of 30 to 95. This is because if the haze value is smaller than the above range, a sufficient light scattering effect may not be obtained.

  Furthermore, in this invention, the light shielding part may be formed in pattern shape on the said transparent substrate. This is because the contrast can be further improved.

  The present invention also provides a self-luminous display device using the color filter described above. By using the color filter, it is possible to obtain a display with high contrast and high brightness with excellent light scattering characteristics of the three primary colors.

  According to the present invention, since the colored layer itself exhibits light scattering properties, when the color filter of the present invention is used, for example, in an EL display device, an effect of realizing a display with high contrast and high luminance is achieved. Further, by making the content of the fine particles contained in each color coloring pattern constituting the colored layer different from each other, it is possible to improve the scattering characteristics depending on the wavelength of light. Furthermore, it is not necessary to provide a separate light scattering layer according to red light, green light and blue light, and a color filter having excellent scattering characteristics and display quality can be obtained by a simple process.

Hereinafter, the color filter and the self-luminous display device of the present invention will be described in detail.
A. Color filter The color filter of the present invention comprises a transparent substrate and fine particles formed on the transparent substrate and having a light scattering action dispersed in the layer, and is composed of a red coloring pattern, a green coloring pattern, and a blue coloring pattern. The content of the fine particles contained in each of the red color pattern, the green color pattern, and the blue color pattern is different from each other.

The color filter of the present invention will be described with reference to the drawings.
FIG. 1 is a schematic sectional view showing an example of the color filter of the present invention. As illustrated in FIG. 1, a color filter 10 of the present invention includes a transparent substrate 1 and a colored layer 2 formed thereon. The colored layer is formed by dispersing fine particles having a light scattering action in the layer, and the colored layer itself exhibits light scattering properties.

  As described above, in the present invention, since the colored layer itself exhibits light scattering properties, when the color filter of the present invention is used in, for example, an EL display device, reflection of external light is suppressed and contrast is improved. It is possible to improve the light extraction efficiency by suppressing total reflection of light emission at the interface between the transparent substrate and the emission medium (for example, air).

  Further, as illustrated in FIG. 1, the colored layer 2 is composed of a red colored pattern 2R, a green colored pattern 2G, and a blue colored pattern 2B. It will be. The content of the fine particles is different depending on each color coloring pattern.

  FIG. 2 is a graph showing an example of scattering characteristics of a conventional color filter. In this graph, a color filter is arranged between the light source and the light receiver, and the light receiver is changed by ± 30 °, and red light (R), green light (G), and blue light (B) It is the result of measuring each scattering intensity. According to the graph illustrated in FIG. 2, for example, when the light receiving angle is 10 °, the scattering intensity decreases in the order of blue light (B)> green light (G)> red light (R). This is because the light scattering intensity depends on the wavelength, and light having a shorter wavelength is more strongly scattered.

  In the present invention, as described above, the content of the fine particles contained in the red color pattern, the green color pattern, and the blue color pattern are different from each other. > The order of the blue coloring pattern can be reduced. In general, since the scattering intensity increases as the content of fine particles increases, the scattering intensity of red light is increased by reducing the content of fine particles in the order of red coloring pattern> green coloring pattern> blue coloring pattern. The scattering intensity distribution of green light and blue light can be made uniform. Accordingly, in the present invention, by appropriately adjusting the content of the fine particles in each color coloring pattern, the scattering characteristics depending on the wavelength of light as illustrated in FIG. 2 can be improved, thereby depending on the viewing angle. It is possible to suppress the occurrence of color shift.

  In addition, each color coloring pattern in the present invention is a dispersion of fine particles. In order to control the scattering intensity of red light, green light, and blue light, when forming each color coloring pattern, for example, in each color coloring pattern Since the concentration of the fine particles and the thickness of each color coloring pattern may be adjusted as appropriate, a color filter can be produced in the same process as the patterning of the conventional colored layer. Therefore, a color filter having excellent scattering characteristics can be obtained without increasing special processes.

In the present invention, a light shielding portion may be formed on the transparent substrate. This is because the contrast can be further improved.
Hereinafter, each configuration of the color filter of the present invention will be described.

1. Colored layer The colored layer used in the present invention is obtained by dispersing fine particles having a light scattering action in the layer. When the color filter of the present invention is used in, for example, an EL display device, the light emitting layer in the EL display device is used. It is provided in order to cause appropriate scattering to the emitted light and to ensure sufficient visibility.

The colored layer is composed of a red colored pattern, a green colored pattern, and a blue colored pattern, and the content of fine particles contained in each color colored pattern is different from each other. In the present invention, for example, the thickness of each color coloring pattern is different, or the concentration of fine particles in each color coloring pattern is different, so that the content of fine particles contained in each color coloring pattern is different. be able to.
Note that the content of the fine particles contained in each color coloring pattern is different from each other, not only when the content of all the fine particles is different among the three colored coloring patterns, but also of the fine particles contained in at least the two colored coloring patterns. This includes cases where the content is different. For example, the content of the fine particles contained in the green coloring pattern and the blue coloring pattern are the same, the content of each fine particle contained in the green coloring pattern and the blue coloring pattern, and the content of the fine particles contained in the red coloring pattern May be different.

  In general, since light having a shorter wavelength is more strongly scattered, for example, when improving the wavelength-dependent scattering characteristics as shown in FIG. 2, the scattering intensity of each color coloring pattern is: red coloring pattern ≧ green coloring pattern > It is preferable to decrease in the order of the blue coloring pattern. That is, it is preferable that the content of the fine particles contained in the blue coloring pattern is smaller than the content of the respective fine particles contained in the red coloring pattern and the green coloring pattern.

  When the color filter of the present invention is applied to an EL display device using a light emitting layer that emits white light, white light from the light emitting layer mainly has a red component and a blue component, and has a strong blue tint. Since a tendency to become light is observed, it is preferable to adjust the scattering intensity of each color coloring pattern so that the scattering intensity of red light is increased with respect to blue light. In this case, the scattering intensity of each color can be made uniform by decreasing the scattering intensity of each color coloring pattern, for example, in the order of red coloring pattern≈green coloring pattern> blue coloring pattern. That is, in the above case, in order to adjust the scattering intensity of each color, the content of the fine particles contained in the blue coloring pattern is made smaller than the content of the respective fine particles contained in the red coloring pattern and the green coloring pattern. That's fine.

  For example, when the thickness of each color coloring pattern is different, the thickness of each color coloring pattern is appropriately adjusted according to the intended scattering intensity of red light, green light, and blue light. Specifically, the thickness of each color coloring pattern is such that it does not impair the transmittance of the colored layer, and is not particularly limited as long as patterning is possible, and is set at about 1.0 μm to 10.0 μm. Preferably, it exists in the range of 1.0 micrometer-5.0 micrometers, More preferably, it exists in the range of 1.5 micrometers-3.5 micrometers. If the thickness of each color coloring pattern is thinner than the above range, for example, when forming each color coloring pattern using an ultraviolet curable resist or the like, the resist component governing the adhesion to the transparent substrate decreases, and the uneven surface is formed by fine particles. This is because film formation may occur due to development. At this time, if the thickness of each color coloring pattern is too thin, each fine particle is developed and a desired pattern may not be obtained. On the other hand, if the thickness of each color coloring pattern is thicker than the above range, the transmittance of the colored layer may decrease. Moreover, when the thickness of each color coloring pattern is too thick, when ultraviolet light exposure is used, light does not reach the lower part of the colored layer, and the pattern becomes unexposed and patterning characteristics may not be obtained.

  On the other hand, for example, when the concentration of fine particles in each color coloring pattern is different, the concentration of the fine particles is appropriately adjusted according to the intended scattering intensity of red light, green light, and blue light. Specifically, the concentration of the fine particles in each color coloring pattern is not particularly limited as long as it is an amount that can scatter light and does not impair the transmittance of the colored layer. %, Preferably in the range of 5 wt% to 30 wt%, more preferably in the range of 10 wt% to 25 wt%. This is because if the concentration of the fine particles is lower than the above range, the light scattering effect may not be obtained. Conversely, if the concentration of the fine particles is higher than the above range, the transmittance of the colored layer may be lowered.

  As described above, since light having a shorter wavelength is generally more strongly scattered, for example, when improving the wavelength-dependent scattering characteristics as shown in FIG. It is preferable to decrease in the order of coloring pattern> blue coloring pattern. This is because the scattering intensity generally increases as the concentration of fine particles increases.

  In addition, when the color filter of the present invention is applied to an EL display device using a light emitting layer that emits white light, as in the case described above, the scattering intensity of red light is increased with respect to blue light. It is preferable to adjust the concentration of fine particles in each color coloring pattern, and by reducing the concentration of fine particles in each color coloring pattern, for example, in the order of red coloring pattern≈green coloring pattern> blue coloring pattern, the scattering intensity of each color can be reduced. Can be aligned.

  Thus, when the density | concentration of the microparticles | fine-particles in each color coloring pattern differs, the thickness of each color coloring pattern may be the same and may differ.

  The colored layer used in the present invention is usually formed by dispersing the fine particles and the colorant in a resin. Hereinafter, the constituent material of the colored layer and other points will be described.

(1) Fine particles The fine particles used in the present invention are not particularly limited as long as they have a light scattering action. For example, inorganic substances such as silicon oxide, aluminum oxide, barium sulfate, acrylic resins, divinylbenzene Fine particles such as resin, benzoguanamine resin, styrene resin, melamine resin, acrylic-styrene resin, polycarbonate resin, polyethylene resin, polyvinyl chloride resin, or a mixture of two or more of these Can be mentioned.

  The fine particles preferably have transparency. This is because the total light transmittance and the diffuse light transmittance can be improved. As such fine particles, among the above, melamine resins, benzoguanamine resins, polymethyl methacrylate resins, mixed resins and copolymers thereof are preferably used. These fine particles also have durability.

Here, it is generally known that the particle size of the fine particles has a great influence on the optical design of the layer exhibiting light scattering properties, and specifically, the scattering state varies depending on the particle size d of the fine particles. That is,
(1) When the particle size d is larger than the light wavelength λ (d> λ), the region becomes a geometric optical region, geometric optical refraction and scattering due to reflection occur, and there is no wavelength dependency.
(2) When the particle diameter d is close to the light wavelength λ (λ / 3 <d <λ), it becomes a diffraction scattering region (Mie scattering), and scattering due to geometric optical scattering and diffraction effect (light interference) occurs. And has a complicated wavelength dependency. For this reason, coloring due to scattering occurs.
(3) When the particle diameter d is smaller than the light wavelength λ (d <λ / 3), it becomes a Rayleigh scattering region, scattering due to interaction with atoms / molecules occurs, and the scattering is almost uniformly performed in all directions. For this reason, not only forward scattering but also back scattering occurs.

  When the color filter of the present invention is used, for example, in an EL display device, the contrast is improved by suppressing reflection of outside light, and the total reflection of light emission at the interface between the transparent substrate and the emission medium (for example, air) is suppressed. In order to improve the light extraction efficiency, omnidirectional scattering is not preferable. Therefore, it is preferable that the particle diameter of the fine particles corresponds to the case (1) or (2) having excellent forward scattering characteristics among the above. Furthermore, in order to prevent coloring due to scattering, the particle diameter of the fine particles is preferably in the geometric optical region (1).

  Moreover, in order to make the intensity of the scattered light by the colored layer sufficient, it is necessary to increase the haze value [haze value = (diffuse light transmittance) / (total light transmittance) × 100]. In particular, in an EL display device, a higher haze value is required. This is because, for example, external light is sometimes used as a light source in a liquid crystal display device. In this case, reflected light is actively used for display, whereas an EL element is a self-luminous element. This is because it is preferable to suppress reflection of external light in order to improve display quality. If the haze value is higher, reflection of external light can be effectively suppressed, and total reflection of light emission at the interface between the transparent substrate and the emission medium (for example, air) can also be effectively suppressed.

  In order to enable a high haze value (high dustiness), it is necessary to increase the concentration of fine particles in each color coloring pattern or to increase the thickness of each color coloring pattern. It is not preferable that the diffused light transmittance is lowered. For example, when titanium oxide or calcium carbonate known as general fine particles is used for the colored layer, the haze value can be increased by increasing the concentration of fine particles in the colored layer or increasing the thickness of the colored layer. Although it can be increased, the light shielding property of the fine particles is developed, and the total light transmittance is remarkably lowered.

From the above, the average particle size of the fine particles used in the present invention is preferably in the range of 1.0 μm to 1.6 μm, more preferably 1.0 μm to 1.4 μm, and still more preferably 1.2 μm. Within the range of ~ 1.4 μm. This is because when the average particle size is in the above range, a high haze value can be achieved and excellent scattering characteristics can be obtained. As described above, only by controlling the concentration of the fine particles in the colored layer or the thickness of the colored layer, the haze value increases, but the total light transmittance may decrease. By doing, haze value can be raised, suppressing the fall of a total light transmittance and a diffused light transmittance. Furthermore, since reflection of external light can be suppressed without using a circularly polarizing plate as described above, when the color filter of the present invention is used, for example, in an EL display device, light emission from the light emitting layer is effective. It is possible to improve the luminance.
Furthermore, when the average particle diameter is in the above range, a uniform film thickness distribution can be achieved by application with a normal spinner, and a relatively thin colored layer having excellent patterning characteristics can be formed. In addition, as described above, depending on the particle size of the fine particles, the colored layer may be colored due to scattering. However, the color characteristics of the colored layer can be reliably compensated for by correcting the color characteristics of the colored layer. Can be effectively suppressed.

  As can be explained from the relationship between the particle diameter d and the light wavelength λ, the scattering intensity distribution of red light, green light, and blue light tends to be uniform as the average particle diameter of the fine particles increases. In consideration of the haze value as described above, the average particle diameter of the fine particles is preferably in the above range. The haze value that serves as an index of the light scattering effect greatly depends on the average particle size of the fine particles, and it is considered that there is a suitable average particle size of the fine particles in order to obtain the light scattering effect in consideration of contrast, brightness, etc. Because.

  Here, the average particle diameter is generally used to indicate the particle size of the particles, and in the present invention, is a value measured 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 and thinning and calculating scattered light obtained by applying a laser beam to the dispersion solvent. 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 shape of the fine particles is not particularly limited, but is preferably spherical.

  In the present invention, the refractive index of the fine particles is preferably larger than the refractive index of the resin described later. Generally, in order to express the scattering characteristics, the difference in refractive index between the fine particles and the resin is used, and ideally, the refractive index of the resin is preferably set to be larger than the refractive index of the fine particles. . However, in order to clarify the difference in refractive index between the fine particles and the resin and to consider the coloring of the colored layer, it is preferable to set the refractive index of the fine particles to be larger than the refractive index of the resin.

  Since the refractive index of the resin described later is generally about 1.5, the refractive index of the fine particles is preferably larger than 1.5. Examples of such fine particles include aluminum oxide (1.62), benzoguanamine / formaldehyde condensate (1.66), benzoquamine / melamine / formaldehyde condensates (1.66, 1.52), and melamine / formaldehyde condensates ( 1.66), silica / acrylic compound (1.52), methacrylic compound (1.51) and the like. The numbers in parentheses indicate the refractive index.

(2) Colorant As the colorant used in the present invention, colorants generally used for color filters can be used, and examples thereof include pigments such as organic pigments and inorganic pigments, and dyes.

(3) Resin The resin used in the present invention is appropriately selected in consideration of the difference in refractive index from the fine particles, the transmittance of the colored layer, the adhesion to the transparent substrate, and the like. Examples of the resin include acrylic resins, epoxy resins, polyvinyl alcohol resins, polyimide resins, vinyl ether resins, and the like. These resins can be used alone or as a mixture of two or more.

  Moreover, when forming each color coloring pattern, for example using an ultraviolet curable resist etc., as a monomer used for a resist, the crosslinkable monomer generally used for a negative resist can be used. Specific examples include trimethylolpropane triacrylate, dipentaerythritol pentaacrylate, dipentaerythritol hexaacrylate, divinylbenzene, and the like. These monomers can be used alone or in admixture of two or more.

  Furthermore, additives such as a leveling agent and an adhesion aid may be added as necessary in order to improve defects during patterning and surface properties of the colored layer.

(4) Others The total light transmittance of the colored layer used in the present invention is preferably 85% or more, more preferably 90% or more, and most preferably 95% or more. This is because if the total light transmittance is too small, the luminance may decrease when the color filter of the present invention is used in, for example, an EL display device.

  Moreover, it is preferable that the haze value of a colored layer is about 30-95, More preferably, it exists in the range of 40-80, Most preferably, it exists in the range of 50-70. This is because if the haze value is smaller than the above range, a sufficient light scattering effect may not be obtained.

  In addition, said total light transmittance and haze value are the values measured with the direct reading haze meter by Toyo Seiki Seisakusho Co., Ltd. using the integrating sphere.

  The arrangement of each color coloring pattern constituting the colored layer is not particularly limited, and examples thereof include a stripe type, a mosaic type, a triangle type, and a four pixel arrangement type.

  In the case where a light shielding portion to be described later is not formed in the non-display area, it is preferable that each color coloring pattern is formed without a gap. This is because the contrast can be improved.

The colored layer used in the present invention can be formed by a general pigment dispersion method, dyeing method, electrodeposition method, printing method or the like.
When the colored layer is formed by the pigment dispersion method, a colored layer forming coating solution containing fine particles, a colorant, and a resin is used. In this case, the colored layer forming coating solution is preferably an ultraviolet curable resist, and more preferably a negative ultraviolet curable resist. This is because, if the coating liquid for forming the colored layer is an ultraviolet curable resist, patterning can be easily performed by exposure through a photomask, for example.

2. Transparent substrate The transparent substrate used in the present invention is not particularly limited as long as it can be generally used for a self-luminous display device. For example, inflexible transparent rigid materials such as quartz glass, Pyrex (registered trademark) glass, and synthetic quartz plates, or transparent flexible materials having flexibility such as transparent resin films and optical resin plates may be used. it can. Among these, Corn 2000 Eagle 2000 or 1737 glass is a material having a small coefficient of thermal expansion, excellent dimensional stability and workability in high-temperature heat treatment, and is a non-alkali glass containing no alkali component in the glass. Are preferably used. It is particularly suitable when the color filter of the present invention is applied to an active drive type EL display device.

3. Light Shielding Part In the present invention, for example, as shown in FIG. 3, the light shielding part 3 may be formed in a non-display area on the transparent substrate 1. This light-shielding part is provided to shield between colored patterns of the colored layer, or to align the colored patterns. In this case, the light-shielding part is formed, for example, for each opening of the colored pattern, thereby improving the contrast.
Further, in order to shield the peripheral edge of the panel of the EL display device, a light shielding portion may be formed at the peripheral edge of the color filter.

  The light shielding part used in the present invention can be formed of a light shielding resin, a metal such as chromium, for example.

4). Flattening layer In the present invention, in order to form a flat surface without fine irregularities on the colored layer surface, or to form a flat surface without irregularities due to each color coloring pattern of the colored layer, A planarization layer may be formed on the layer.

  In particular, when an EL display device is manufactured using the color filter of the present invention, for example, when a transparent electrode layer or the like is formed on a colored layer in the color filter, the planarizing layer is formed. Is preferred. Since the colored layer contains fine particles, fine irregularities are likely to occur on the surface, and it may be difficult to form a uniform transparent electrode layer. However, since the planarized layer is formed on the colored layer, the colored layer is uniform. This is because a transparent electrode layer can be formed. In addition, when the transparent electrode layer reflects irregularities due to the colored patterns of the colored layers, a short circuit may occur between the electrodes. By forming a planarizing layer, a short circuit between the electrodes can be prevented. Because you can.

  On the other hand, for example, in the case where an EL display device is manufactured by separately manufacturing and attaching a color filter and a counter substrate, the planarization layer may not be formed.

  The planarization layer used in the present invention can be formed using, for example, an acrylic resin, an epoxy resin, a vinyl ether resin, a polyimide resin, a propynyl resin, or the like.

5. Gas Barrier Layer In the present invention, a gas barrier layer may be formed on the colored layer. When the planarizing layer is formed, a gas barrier layer may be formed on the colored layer or the planarizing layer. For example, since a light emitting layer and other organic layers in an EL display device are members that are weak against oxygen, water vapor, and other gases, the formation of dark spots and dark areas can be suppressed by providing a gas barrier layer. Because. In particular, when an EL display device is manufactured or driven, gas may be generated from a colored layer or the like. However, the gas barrier layer can suppress deterioration of the light emitting layer or the like due to the generated gas.

  As the gas barrier layer, those generally used as a gas barrier layer of an EL display device can be used. For example, silicon oxide, silicon nitride, silicon oxynitride or the like is used.

6). Transparent electrode layer In this invention, the transparent electrode layer may be formed on the colored layer. In the case where the planarizing layer or the gas barrier layer is formed, a transparent electrode layer may be formed on any one of the colored layer, the planarizing layer, and the gas barrier layer.
As the transparent electrode layer used in the present invention, for example, indium tin oxide (ITO), zinc oxide (ZnO), tin oxide (SnO), or an alloy thereof is used. The transparent electrode layer can be formed by a general film forming method such as a sputtering method, a vacuum vapor deposition method, a CVD method or the like.

  The thickness of the transparent electrode layer can be set to about 0.01 μm to 1 μm, and preferably about 0.03 μm to 0.5 μm.

7). Others The haze value of the color filter of the present invention is preferably about 30 to 95, more preferably in the range of 40 to 80, and most preferably in the range of 50 to 70. This is because if the haze value is smaller than the above range, a sufficient light scattering effect may not be obtained. From the viewpoint of front luminance, the upper limit of the haze value is preferably 95.

  The haze value is a value measured using a direct reading haze meter manufactured by Toyo Seiki Seisakusho.

  The color filter of the present invention can be applied to a self-luminous display device such as an EL display device, a plasma display (PDP), and a field emission display (FED). By using the color filter of the present invention, it is possible to obtain a display with high contrast and high brightness with excellent light scattering characteristics of the three primary colors. Among these, the color filter of the present invention is preferably applied to an EL display device.

B. Self-luminous display device Next, the self-luminous display device of the present invention will be described. The self-luminous display device of the present invention is characterized by using the color filter described above.
Examples of the self-luminous display device include an EL display device, a plasma display (PDP), and a field emission display (FED). Among these, an EL display device is preferable. The EL display device may be an organic EL display device or an inorganic EL display device.

  In the present invention, the EL display device is preferably driven by an active drive method. This is because the color filter can suppress reflection of external light and is suitable for a display device used for a digital still camera or a digital video movie used in an external environment. In general, since a digital still camera, a digital video movie, or the like has a megapixel resolution, a resolution is also required for a display device that displays the resolution. A passive drive display device cannot obtain high resolution due to its configuration, and high-definition display devices have generally shifted to an active drive method. Further, regarding the display colors of colors, an active drive type display device capable of controlling an intermediate color with a thin film transistor (TFT) element can reproduce many display colors.

FIG. 4 shows an example of an EL display device of the present invention. 4A illustrates an example of a bottom emission EL display device, and FIG. 4B illustrates an example of a top emission EL display device.
For example, in the EL display device 30 shown in FIG. 4A, the transparent electrode layer 12, the light emitting layer 11, and the metal electrode layer 13 are formed on the colored layer 2 (2R, 2G, and 2B) of the color filter 10, and the A substrate 15 is formed thereon. A partition wall 16 is formed between the light emitting layers 12, and the transparent electrode layer 12 is formed together with a thin film transistor (TFT) 17.
For example, in the EL display device 30 illustrated in FIG. 4B, the counter substrate in which the color filter 10 and the metal electrode layer 13, the light emitting layer 11, the transparent electrode layer 12, and the refractive index matching layer 14 are formed on the substrate 15. 20 are stacked. A partition wall 16 is formed between the light emitting layers 12, and the metal electrode layer 13 is formed together with a thin film transistor (TFT) 17.
The color filter suppresses reflection of external light and suppresses total reflection of light emission at the interface between the transparent substrate and the emission medium, and is disposed on the light extraction surface side in any EL display device. .

  Among bottom emission and top emission, top emission is advantageous in that the ratio of the light emitting portion (light emission area ratio) is large. This is because, in bottom emission, the TFT circuit is formed on the light extraction surface side, so the light emission area is reduced. In top emission, light is extracted from the surface opposite to the TFT circuit formation surface. This is because even if a complicated TFT circuit is formed, the light emitting area is not affected.

  In addition, as an EL display device, for example, an EL display device using a light emitting layer that emits white light, an EL display device using a light emitting layer that emits light of each of the three primary colors, and a light emitting layer that emits blue light, and the three primary colors by color conversion. Any of the EL display devices that display a light emitting diode may be used, but among them, an EL display device using a light emitting layer that emits white light is preferable.

  As other constituent members of the EL display device, for example, a light emitting layer, those generally used 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 with reference to examples.
[Example 1]
(Formation of black matrix)
A soda glass (manufactured by Central Glass Co., Ltd.) having a thickness of 370 mm × 470 mm and a thickness of 0.7 mm was used as a transparent substrate, and a thin film (thickness 0.2 mm) of oxynitride composite chromium was formed on the transparent substrate by sputtering. A photosensitive resist is applied on the composite chrome thin film, and mask exposure, development, and etching of the composite chrome thin film are sequentially performed so that a rectangular opening of 80 μm × 280 μm has a pitch of 100 μm in the short side direction and a long side. A black matrix arranged in a matrix at a pitch of 300 μm in the direction was formed.

(Formation of colored layer)
Photosensitive coating compositions for forming red, green and blue colored patterns were prepared. Condensed azo pigments (manufactured by Ciba Specialty Chemicals, Chromophthalred BRN) as red colorants, phthalocyanine green pigments (Lionol Green 2Y-301, manufactured by Toyo Ink Co., Ltd.), and blue as green colorants As the colorant, anthraquinone pigment (Ciba Specialty Chemicals, Chromophthal Blue A3R) was used. Moreover, polyvinyl alcohol (10% aqueous solution) was used as the binder resin. Each colorant was blended at a ratio of 1 part (all parts are based on mass) to 10 parts of the polyvinyl alcohol aqueous solution.
To 100 parts of the resulting solution, 1 part of ammonium dichromate is added as a cross-linking agent. Furthermore, 20 parts for the red photosensitive coating composition and 17 parts for the green photosensitive coating composition with respect to 100 parts of the solid content. In the case of blue photosensitive coating composition, 12 parts of scattering fine particles (melamine resin beads, average particle size 1.2 μm) are added and mixed thoroughly to form a photosensitive coating composition for forming each colored pattern. Obtained.

  Each colored pattern was formed using the above-mentioned photosensitive coating composition for forming each colored pattern. That is, the red photosensitive coating composition was applied on the transparent substrate on which the black matrix was formed by spin coating, and prebaked at 100 ° C. for 5 minutes. Then, it exposed using the photomask and developed with the developing solution (0.05% KOH aqueous solution). Next, post baking was performed at 200 ° C. for 60 minutes to synchronize with the black matrix pattern, and a striped red colored pattern having a width of 85 μm and a thickness of 1.5 μm was formed. Thereafter, a green photosensitive coating composition and a blue photosensitive coating composition were sequentially used to form stripe-shaped green coloring patterns and blue coloring patterns having a width of 85 μm and a thickness of 1.5 μm.

(Formation of planarization layer)
Next, for the formation of a flattened layer in which an acrylate-based photocurable resin (manufactured by Nippon Steel Chemical Co., Ltd., trade name: “V-259PA / PH5”) is diluted with propylene glycol monomethyl ether acetate after the colored layer is formed. A coating solution was prepared, applied by spin coating, and prebaked at 120 ° C. for 5 minutes. Subsequently, after patterning by photolithography, post-baking was performed at 200 ° C. for 60 minutes to form a flattened layer having a thickness of 5 μm.

(Formation of gas barrier layer)
Next, a Si ₃ N ₄ target (3N) is used on the above planarization layer by sputtering to form an argon gas introduced amount: 40 sccm, RF power: 430 kW, substrate temperature: 100 ° C., and a thickness of 150 nm. A silicon oxynitride film was laminated to form a transparent gas barrier layer.
A color filter was produced by the series of operations described above.

(Formation of transparent electrode layer)
Next, an indium tin oxide (ITO) electrode film having a film thickness of 150 nm is formed on the gas barrier layer by ion plating, a photosensitive resist is applied on the ITO electrode film, mask exposure, development, and ITO electrode film Etching was performed to form a transparent electrode layer.

(Formation of auxiliary electrode)
Next, a chromium thin film (thickness 0.2 μm) is formed by sputtering on the entire surface of the gas barrier 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.

(Formation of insulating layer and partition wall)
Using a coating solution for forming an insulating layer obtained by diluting norbornene-based resin having an average molecular weight of about 100,000 (manufactured by JSR, ARTON) with toluene, the transparent electrode layer is covered on the gas barrier layer by spin coating. After the application, 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 stripe-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 material (manufactured by Nippon Zeon Co., Ltd., photoresist ZPN1100) was applied over the entire surface by spin coating so as to cover the insulating layer, and prebaked (70 ° C., 30 minutes). Then, it exposed using the predetermined | prescribed photomask, developed with the developing solution (Nippon-Zeon company make, ZTMA-100), and then post-baked (100 degreeC, 30 minutes). Thereby, the partition part was formed on the insulating layer.

(Formation of organic EL layer)
Subsequently, the organic EL layer which consists of a positive hole injection layer, a white light emitting layer, and an electron injection layer was formed by the vacuum evaporation method.

That is, first, N, N′-diphenyl-N, N′-bis (3-methylphenyl)-[1,1′-biphenyl] -4,4′-diamine is added to a predetermined opening corresponding to the display area. A hole injection layer was formed on the transparent electrode layer by forming a film by vapor deposition up to 600 nm through a provided photomask. Similarly, 4,4′-bis (2,2-diphenylvinyl) biphenyl was deposited to a thickness of 50 nm to form a film. At the same time, a small amount of rubrene (manufactured by Aldrich Co., Ltd., fluorescence peak wavelength 585 nm) was contained. This formed the white light emitting layer.
Thereafter, tris (8-quinolinol) aluminum was deposited to a thickness of 20 nm to form an electron injection layer. The organic EL layer thus formed was present between the partition walls as a stripe pattern having a width of 280 μm.

(Formation of metal electrode layer)
Next, magnesium and silver are simultaneously vapor-deposited by a vacuum vapor deposition method (magnesium vapor deposition rate = through a photomask having a predetermined opening wider than the display area, in a region where the partition wall is formed. The film was formed at a rate of 1.3 to 1.4 nm / second and a silver deposition rate of 0.1 nm / second. Thereby, the partition wall portion was used as a mask to form a metal electrode layer made of magnesium / silver compound with a thickness of 200 nm on the organic EL layer. This metal electrode layer was present on the organic EL layer as a stripe pattern having a width of 280 μm.

(Organic EL display device)
The organic EL element was sealed to obtain an organic EL display device.
(Evaluation)
Desirable that the transparent electrode layer and the metal electrode layer intersect each other by applying a DC voltage of 8.5 V to the transparent electrode layer and the metal electrode layer of the organic EL display device at a constant current density of 10 mA / cm ² and continuously driving the same. The light emitting layer of the part was made to emit light.
Color shift (Δxy in CIE chromaticity coordinates) when tilted 45 ° from the front of the substrate with a spectral radiance meter (SR-2, manufactured by Topcon Co., Ltd.) for an arbitrary region of the obtained organic EL display device And visibility under the bright room (external light reflection reduction effect) were evaluated. The results are shown in Table 1.
Here, Δxy is obtained from the following equation from the White coordinates (x2, y2) when inclined by 45 ° with respect to the substrate surface with respect to the White coordinates (x1, y1) at the front of the substrate when all colors are lit. Calculated.
Δxy = ((x1−x2) ² + (y1−y2) ² ) ^1/2

  Further, the haze value of the color filter was measured with a direct reading haze meter manufactured by Toyo Seiki Seisakusho. The results are shown in Table 1 below.

[Example 2]
An organic EL display device was produced in the same manner as in Example 1 except that the colored layer was formed as described below.

(Formation of colored layer)
In Example 1, a colored layer was formed in the same manner as in Example 1 except that the addition ratio of the scattering fine particles to be added was changed when preparing the photosensitive coating composition for forming each colored pattern. That is, 40 parts of the red photosensitive coating composition, 35 parts of the green photosensitive coating composition, and 27 parts of the blue photosensitive coating composition, 27 parts of scattering fine particles (melamine resin beads, average Particle size 1.2 μm) was added.

(Evaluation)
Evaluation similar to Example 1 was performed.

[Example 3]
An organic EL display device was produced in the same manner as in Example 1 except that the colored layer was formed as described below.

(Formation of colored layer)
In Example 1, a colored layer was formed in the same manner as in Example 1 except that the addition ratio of the scattering fine particles to be added was changed when preparing the photosensitive coating composition for forming each colored pattern. That is, 32 parts of the red photosensitive coating composition, 32 parts of the green photosensitive coating composition, and 25 parts of the blue photosensitive coating composition with respect to the solid content of 100 parts (25 parts of scattering fine particles (melamine resin beads, average Particle size 1.2 μm) was added.

(Evaluation)
Evaluation similar to Example 1 was performed.

[Comparative Example 1]
An organic EL display device was produced in the same manner as in Example 1 except that the colored layer was formed as described below.

(Formation of colored layer)
In Example 1, a colored layer was formed in the same manner as in Example 1 except that the addition ratio of the scattering fine particles to be added was changed when preparing the photosensitive coating composition for forming each colored pattern. That is, 20 parts of the red photosensitive coating composition, 20 parts of the green photosensitive coating composition, and 20 parts of the blue photosensitive coating composition with respect to the solid content of 100 parts (melamine resin beads, average Particle size 1.2 μm) was added.

(Evaluation)
Evaluation similar to Example 1 was performed.

[Comparative Example 2]
An organic EL display device was produced in the same manner as in Example 1 except that the colored layer was formed as described below.

(Formation of colored layer)
In Example 1, a colored layer was formed in the same manner as in Example 1 except that the addition ratio of the scattering fine particles to be added was changed when preparing the photosensitive coating composition for forming each colored pattern. That is, 7 parts of the red photosensitive coating composition, 7 parts of the green photosensitive coating composition, and 7 parts of the blue photosensitive coating composition with respect to 100 parts of the solid content (melamine resin beads, average Particle size 1.2 μm) was added.

(Evaluation)
Evaluation similar to Example 1 was performed.

  As is clear from Table 1, in Examples 1 to 3, color misregistration could be suppressed and visibility was good. On the other hand, in Comparative Examples 1 and 2, the color misregistration cannot be suppressed because the content of the scattering fine particles in each colored pattern is equal, and in Comparative Example 2, the haze value is low, and the visibility is poor.

It is a schematic sectional drawing which shows an example of the color filter of this invention. It is a graph which shows an example of the scattering characteristic of the conventional color filter. It is a schematic sectional drawing which shows the other example of the color filter of this invention. It is a schematic sectional drawing which shows an example of the EL display apparatus of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Transparent substrate 2 ... Colored layer 2R ... Red colored pattern 2G ... Green colored pattern 2B ... Blue colored pattern 3 ... Light-shielding part 10 ... Color filter

Claims (6)

  A transparent substrate and a colored layer formed on the transparent substrate, in which fine particles having a light scattering effect are dispersed in the layer, and a red colored pattern, a green colored pattern, and a colored layer composed of a blue colored pattern, The color filter, wherein the content of the fine particles contained in each of the red coloring pattern, the green coloring pattern, and the blue coloring pattern is different from each other.   2. The color filter according to claim 1, wherein the content of the fine particles contained in the blue colored pattern is less than the content of the fine particles contained in the red colored pattern and the green colored pattern.   3. The color filter according to claim 1, wherein an average particle diameter of the fine particles is in a range of 1.0 μm to 1.6 μm.   The color filter according to any one of claims 1 to 3, wherein a haze value is in a range of 30 to 95.   The color filter according to any one of claims 1 to 4, wherein a light shielding portion is formed in a pattern on the transparent substrate.   A self-luminous display device using the color filter according to any one of claims 1 to 5.

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