JP6550785B2 - Color filter and display device - Google Patents

Description

  The present invention relates to a color filter used in a display device such as a liquid crystal display device or an organic EL display device.

In recent years, with the development of display devices, demand for flat panel displays such as liquid crystal display devices and organic EL display devices has increased. Recently, in addition to televisions and personal computers, multi-functional terminals such as smartphones and tablet terminals have become widespread, and the market for flat panel displays is expanding.
In such a situation, high quality materials are desired for members constituting the flat panel display. In particular, in a flat panel display, the quality of the color filter affects the display quality itself, so high quality and design are required.

  A common color filter has a transparent substrate, a light shielding layer formed in a pattern on the transparent substrate, and colored layers of plural colors formed in the opening of the light shielding layer. Such a color filter is arranged, for example, such that the transparent substrate is on the viewer side, and is incorporated in a flat panel display.

In a display device using a color filter, a color image is generally formed by pixels of three colors of RGB. That is, on the CIE chromaticity diagram, the ratio of three colors of RGB is changed to reproduce colors in the range of the triangle of RGB. Therefore, the colors outside the triangle represented by the three colors RGB cannot be reproduced.
In flat panel displays that require high quality and designability, expansion of color reproducibility using these three color pixels is required. In addition, there is a growing demand for higher brightness due to reduced power consumption of a backlight that is a light source of a display device and characteristics of an LED backlight.

JP 2004-176000 A

However, when attempting to increase the color reproducibility of a flat panel display, the transmission wavelength band of the color filter must be set narrow in order to increase the color purity of the display color in order to widen the color reproduction range. For this reason, if it is intended to increase the color purity of the display color, the amount of light transmitted through the color filter (hereinafter, the amount of light transmitted through the color filter may be reduced) decreases to lower the transmitted light luminance. Arise.
In addition, a display device having a color filter has a problem that light transmittance and pixel luminance in a colored layer of a specific color are lower than light transmittance and pixel luminance in a colored layer of another color depending on the type of light source. . For example, in an organic EL display device having a color filter in which the light source is a white light emitting element, the red colored layer tends to have a high white light transmittance as compared with the green and blue colored layers. Also, the green colored layer tends to have a higher transmitted light luminance as compared to the red and blue colored layers. As described above, since the light extraction efficiency varies depending on the color of the colored layer, the amount of transmitted light is individually increased for the colored layer of a specific color having a low transmittance to the light source and a low luminance of transmitted light. Need to improve efficiency.

Here, as a method for expanding the color reproducibility and increasing the brightness, for example, as disclosed in Patent Document 1, a method of selecting a pigment or a dye contained in a colored layer of a color filter is generally used. However, the pigment has a problem that the light transmittance is low and it is difficult to obtain sufficient light extraction efficiency. In addition, when a dye is used as the coloring material, although the light transmittance is higher than that of the pigment, the chromaticity is likely to change due to heating or the like in the manufacturing process. In some cases, the contrast deteriorates. Among them, in the blue colored layer, since the transmission region is on the short wavelength side, there is a problem that the color characteristics are easily deteriorated due to the feature of the above-mentioned color material.
For this reason, there is a limit in improving display luminance in the display device while ensuring sufficient light extraction efficiency in the colored layer of the specific color only by selecting the color material included in the colored layer.

  The present invention has been made in view of the above problems, and a color filter capable of improving light extraction efficiency and display luminance in a display region of a display device in which the color filter is used, and the same The main object is to provide a display device using

  As a result of intensive studies to solve the above problems, the present inventors have improved the luminance between the transparent substrate and the colored layer having a specific thickness and refractive index that match the wavelength of the light transmitted through the colored layer. By arranging the layers, an interference effect between the transmitted light occurs, and the amount of light transmitted through the colored layer (hereinafter, the amount of transmitted light in the colored layer may be increased) can be increased, and the light extraction efficiency is improved. The present invention has been completed.

  That is, the present invention includes a transparent substrate, a light shielding layer formed in a pattern on the transparent substrate, and a plurality of colored layers formed in openings of the light shielding layer, and the transparent substrate and the above A brightness enhancement layer having a specific thickness and refractive index is disposed between at least one color of the plurality of colored layers, and the refractive index of the brightness enhancement layer is at least the refraction of the transparent substrate. A color filter having a refractive index higher than the refractive index and different from the refractive index of the colored layer of one color is provided.

  According to the present invention, since the brightness improving layer having the specific thickness and the refractive index is disposed between the transparent substrate and the specific colored layer of at least one color, the specific colored layer, the brightness improving layer, and the transparent Transmission in the colored layer of a specific color due to the interference effect between the light transmitted through the substrate as it is and the light transmitted through the transparent substrate while being reflected at each interface of the transparent substrate and the brightness enhancement layer and the brightness enhancement layer and the specific color layer The amount of light can be increased, and the luminance can be improved.

  In the said invention, it is preferable that the refractive index of the said brightness improvement layer is higher than the refractive index of the said colored layer of one color. In addition to the light interference effect, the presence of reflected light that is emitted without interfering with other light improves the light transmittance in the colored layer of a specific color, and the effect of the present invention is more easily exhibited. It is.

  In the said invention, it is preferable that the said brightness improvement layer is arrange | positioned between the said transparent substrate and a blue colored layer. Generally, it is particularly difficult to improve the brightness of blue, but by disposing a brightness improving layer between the transparent substrate and the blue colored layer, the amount of transmitted light in the blue colored layer can be increased to increase the transmitted light brightness. It is possible to improve the

  In the above invention, preferably, the brightness improving layer is disposed on the entire surface between the transparent substrate and the colored layers of the plurality of colors and the light shielding layer. By arranging the above-mentioned brightness improving layer between the transparent substrate and the light shielding layer, in addition to the brightness improving effect of the colored layer by the above-mentioned brightness improving layer, the reflected light from the interface between the transparent substrate and the brightness improving layer and the brightness improvement This is because it is possible to cause interference with reflected light from the interface between the layer and the light shielding layer, and to obtain an effect of reducing external light reflection in the light shielding layer due to the light interference effect.

  Moreover, this invention has a transparent substrate, the light shielding layer formed in the pattern form on the said transparent substrate, and the colored layer of the several color formed in the opening part of the said light shielding layer, The said transparent substrate and the said several A brightness enhancement layer having a specific thickness and refractive index is disposed between at least one color of the colored layers, and the refractive index of the brightness enhancement layer is at least the refractive index of the transparent substrate. A display device comprising a color filter that is higher than the refractive index of the colored layer of one color is provided.

  According to the present invention, by providing the above-described color filter, it is possible to increase the amount of transmitted light in the specific colored layer in which the luminance improving layer is disposed, and to improve the display luminance in the display area of the display device.

  In the said invention, it is preferable that the said brightness improvement layer is arrange | positioned between the said transparent substrate and a blue colored layer. Generally, it is particularly difficult to improve the brightness of blue, but by disposing a brightness improving layer between the transparent substrate and the blue colored layer, the amount of transmitted light in the blue colored layer can be increased to increase the transmitted light brightness. It is possible to improve the

  In the present invention, it is possible to improve the light extraction efficiency and improve the display luminance in the display region of the display device in which the color filter is used.

It is a schematic sectional drawing which shows an example of the color filter of this invention. It is a schematic sectional drawing which shows the other example of the color filter of this invention. It is a schematic plan view which shows an example of the color filter of this invention. It is explanatory drawing explaining advancing of the light in the color filter of this invention. 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 the other example of the color filter of this invention. It is a schematic sectional drawing which shows the other example of the color filter of this invention.

  Hereinafter, the color filter and the 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, a light shielding layer formed in a pattern on the transparent substrate, and colored layers of plural colors formed in the opening of the light shielding layer, and the transparent A brightness improving layer having a specific thickness and a refractive index is disposed between the substrate and the colored layer of at least one of the colored layers of the plurality of colors, and the refractive index of the brightness improving layer is at least the transparent. It is characterized by being higher than the refractive index of the substrate and different from the refractive index of the colored layer of one color.

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, the color filter 1 is formed in the opening of the transparent substrate 2, the light shielding layer 4 formed in a pattern on the transparent substrate 2, and the light shielding layer 4. A colored layer 5 in which a colored layer 5G and a blue colored layer 5B are arranged. In addition, between the transparent substrate 2 and the blue colored layer 5B of the colored layers 5, the brightness improving layer 3 having a specific thickness and refractive index adjusted according to the wavelength of blue is disposed. The brightness enhancement layer 3 has a refractive index higher than that of the transparent substrate 2 and different from that of the blue colored layer 5B.
When such a color filter 1 is used for a display device, the transparent substrate 2 of the color filter 1 is disposed on the viewer side, and external light enters from the transparent substrate 2 side.

  FIG. 2 is a schematic cross-sectional view showing another example of the color filter of the present invention. In the color filter 1 shown in FIG. 2, the light shielding layer 4 is formed in a pattern on the transparent substrate 2, and a colored layer having the red coloring layer 5 R, the green coloring layer 5 G and the blue coloring layer 5 B in the opening of the light shielding layer 4. A brightness improving layer 3 having a specific thickness and a refractive index is disposed between the transparent substrate 2 and the blue colored layer 5B. The light shielding layer 4 is formed in the display area 11 and has a pixel division light shielding portion 6 for dividing the pixel P, and a frame light shielding portion 7 formed in the non-display area 12.

  Here, the “display area” refers to an area used for image display when the color filter of the present invention is used in a display device. In addition, the “non-display area” refers to an area arranged on the outer periphery of the display area. For example, as shown in FIGS. 2 and 3, the color filter 1 has a display area 11 and a non-display area 12 arranged on the outer periphery of the display area 11.

According to the present invention, the brightness enhancement layer having a specific thickness and refractive index is disposed between the transparent substrate and the colored layer of the specific color, and the refractive index of the brightness enhancement layer is at least that of the transparent substrate. Since the refractive index is higher than the refractive index and different from the refractive index of the colored layer of the specific color, it is assumed that the following phenomenon occurs.
That is, as illustrated in FIG. 4, the color improvement layer 3 is disposed between the transparent substrate 2 and the colored layer 5 (the blue colored layer 5B in FIG. 4), so that the color filter of the present invention can be used as a display device. When used for the light source, light L from the light source of the display device is light L1 partially transmitted through the blue colored layer 5B, the brightness enhancement layer 3 and the transparent substrate 2 as it is, and a portion is blue colored layer 5B and the brightness It is expected that light transmitted through the enhancement layer 3 and reflected at the interface between the brightness enhancement layer 3 and the transparent substrate 2 is re-reflected at the interface between the brightness enhancement layer 3 and the blue colored layer 5B to become light L2 transmitted through the transparent substrate 2 The For this reason, it is guessed that the transmittance | permeability of the light which permeate | transmits the blue colored layer 5B becomes high. At this time, the transmitted light L1 and the light L2 cause interference with each other, but the thickness and the refractive index of the luminance improving layer 3 are adjusted in accordance with the blue wavelength of the blue colored layer 5B. Thus, it is inferred that the phases of the light 1 and the light 2 coincide with each other to strengthen each other by interference, and the amount of transmitted light in the blue colored layer 5B increases.
As described above, interference between the light transmitted through the colored layer, the brightness enhancement layer and the transparent substrate as it is and the light transmitted through the transparent substrate while being reflected at each interface between the transparent substrate and the brightness enhancement layer, and the brightness enhancement layer and the color layer. Due to the effect, the amount of transmitted light in the colored layer of the specific color is increased, and the transmitted light luminance is improved. Thereby, display luminance can be improved in the display device.
Therefore, by using the color filter of the present invention, the display luminance of the display area can be improved, and a display device with high display quality can be obtained.

  Hereinafter, each structure in the color filter of the present invention will be described.

1. Brightness Enhancement Layer The brightness enhancement layer in the present invention is disposed between the transparent substrate and the colored layer of at least one of the colored layers of the plurality of colors, and has a specific thickness and refractive index. is there. The brightness enhancement layer has a refractive index that is higher than at least the refractive index of the transparent substrate and different from the refractive index of the colored layer of one color.

  In particular, in the present invention, the brightness enhancement layer is preferably disposed between the transparent substrate and the blue colored layer. In general, it is particularly difficult to improve the brightness of blue as compared to other colors, and even if it is intended to improve the display brightness by selecting a color material, the type of color material exhibiting high brightness and blue is limited. As a result, the luminance can not be sufficiently improved. On the other hand, in the present invention, by arranging the brightness enhancement layer between the transparent substrate and the blue colored layer, by increasing the amount of transmitted light in the blue colored layer without selecting a high brightness color material, This is because it is possible to improve the blue luminance.

  In addition, the wavelength of the light which permeate | transmits a colored layer changes for every color of a colored layer, and the interference effect of light changes according to a wavelength. For this reason, the brightness enhancement layer has a thickness and a refractive index condition such that the amount of transmitted light is increased by the light interference effect according to the wavelength of the light transmitted through each colored layer positioned on the brightness enhancement layer. It is possible to design. Then, the thickness and the refractive index of the brightness improving layer which can increase the amount of transmitted light in each colored layer become the “specific thickness and the refractive index” of the brightness improving layer corresponding to the color.

  The specific thickness of the brightness enhancement layer depends on the colored layer positioned on the brightness enhancement layer and the wavelength of light transmitted through the colored layer, but is preferably in the range of 20 nm to 350 nm, for example. As illustrated in FIG. 5B and FIG. 7 to be described later, when a plurality of colored layers are arranged on a single luminance enhancement layer, the specific thickness of the luminance enhancement layer is at least a blue colored layer. It is preferable that the thickness be such that the amount of light transmitted through the blue colored layer increases due to the light interference effect generated in step. This is because blue luminance can be preferentially improved.

In this specification, “thickness” refers to a thickness obtained by a general measurement method. As a method of measuring the thickness, for example, a stylus type method in which the thickness is calculated by detecting unevenness on the surface with a stylus, or an optical method in which the thickness is calculated based on the spectral reflection spectrum, etc. Can do. Specifically, the thickness can be measured using a stylus type thickness meter P-15 manufactured by KLA-Tencor Corporation. In addition, as thickness, the average value of the thickness measurement result in the several location of the member used as object may be used.
Hereinafter, the same applies to other parts in the present invention.

The specific refractive index of the brightness enhancement layer is higher than the refractive index of the transparent substrate because light is reflected at the interface between the transparent substrate and the brightness enhancement layer. It may be different from the refractive index of the layer.
Specifically, the refractive index of the brightness improving layer is preferably more than 1.5 and less than 2.1, and more preferably more than 1.6 and less than 2.1. By setting the refractive index of the brightness enhancement layer within the above range, light reflected at the interface between the transparent substrate and the brightness enhancement layer is reflected again at the interface between the brightness enhancement layer and the colored layer to transmit the transparent substrate. This is because the amount of transmitted light in the colored layer located on the brightness enhancement layer can be increased by the light interference effect. On the other hand, when the refractive index of the brightness improving layer is not within the above range, the light reflectance is too high, which may cause a decrease in the transmittance.
Among them, it is preferable that the specific refractive index of the luminance improving layer be higher than the refractive index of the one-color colored layer. In addition to the light interference effect, the presence of the reflected light emitted without interference with other light improves the light transmittance in the coloring layer of the specific color, and the effect of the present invention is more easily exhibited. Because.
As illustrated in FIG. 5B and FIG. 7 described later, when a plurality of colored layers are disposed on a single brightness enhancement layer, the refractive index of the brightness enhancement layer is higher than that of the transparent substrate. What is necessary is just to differ from the refractive index of a blue colored layer at least, and it is preferable that it is higher than the refractive index of a blue colored layer especially. This is because blue luminance can be preferentially improved.

  Here, “refractive index” refers to a refractive index with respect to light having a wavelength of 550 nm. The method for measuring the refractive index is not particularly limited, and examples thereof include a method of calculating from a spectral reflection spectrum, a method of measuring using an ellipsometer, and an Abbe method. The ellipsometer includes UV-SEL manufactured by Giovanni-Ebon. Specifically, the refractive index can be measured with DF1030R manufactured by Techno Synergy. The same applies to the refractive index of each part described later.

  As shown in FIG. 7 to be described later, when the brightness enhancement layer is disposed on the entire surface between the transparent substrate, the colored layers of the plurality of colors, and the light shielding layer, the refractive index of the brightness enhancement layer is the refractive index of the light shielding portion. Is preferably lower. In addition to the increase in the amount of transmitted light in the colored layer by the brightness improving layer and the improvement effect of the transmitted light brightness, the interference between the reflected light from the interface of the transparent substrate and the brightness improving layer and the reflected light from the interface of the brightness improving layer and the light shielding layer This is because it is possible to further improve the effect of reducing external light reflection at the light shielding layer due to the effect. The reduction in external light reflection at the light shielding layer by the brightness enhancement layer will be described in detail later.

The brightness improving layer in the present invention comprises a binder resin and a first embodiment containing high refractive index fine particles having a refractive index higher than that of the binder resin, and at least one color of a plurality of colored layers higher than the refractive index of the transparent substrate. It can be roughly divided into two modes of the second mode including a resin having a refractive index different from the refractive index of the colored layer or an inorganic material.
Hereinafter, each aspect of the luminance improving layer will be described.

(1) 1st aspect The brightness | luminance improvement layer of this aspect contains high refractive index microparticles | fine-particles whose refractive index is higher than binder resin and binder resin.

  The binder resin used for the brightness improving layer is not particularly limited as long as it can obtain a brightness improving layer having light transmittance and satisfying a specific thickness and refractive index, and film forming property It is appropriately selected from the viewpoint of film strength and the like. Among them, the binder resin is preferably a cured resin cured by irradiation with heat or ionizing radiation such as ultraviolet light and electron beam. As a cured resin, thermosetting resin and ionizing radiation cured resin are mentioned, for example. Among them, ionizing radiation curable resins are preferred. This is because the surface hardness of the brightness improving layer can be increased.

  Here, “ionizing radiation curable resin” refers to a resin cured by irradiation with ionizing radiation. "Ionizing radiation" refers to an electromagnetic wave or charged particle beam that has an energy quantum that can polymerize or crosslink a molecule, for example, an ultraviolet ray, an electron beam, an electromagnetic wave such as X-ray or γ-ray, an α-ray And charged particle beams such as ion beams.

  Examples of the ionizing radiation curable resin include an ultraviolet curable resin and an electron beam curable resin. Among them, UV curable resins are preferred.

  Specifically, as the binder resin, those used for the high refractive index layer described in JP 2013-142817 A, JP 2012-150226 A, JP 2011-170208 A etc. may be mentioned. it can.

The highly refractive fine particles used in the brightness enhancement layer are not particularly limited as long as the refractive index is higher than that of the binder resin and a brightness enhancement layer satisfying a specific refractive index can be obtained. Among these, the refractive index of the high refractive index fine particles is preferably in the range of 1.5 to 2.8.
Examples of such high refractive index fine particles include zirconium oxide (ZrO ₂ , refractive index: 2.0 to 2.10), antimony oxide (Sb ₂ O ₅ , refractive index: 1.79 to 2.04), Antimony tin oxide (ATO, refractive index: 1.75 to 2.05), indium tin oxide (ITO, refractive index: 1.95 to 2.00), phosphorus tin compound (PTO, refractive index: 1.75) To 1.85), β-Al ₂ O ₅ (refractive index: 1.63 to 1.76), γ-Al ₂ O ₅ (refractive index: 1.63 to 1.76), barium titanate (BaTiO ₃₎ , Refractive index: 2.4), titanium oxide (TiO ₂ , refractive index: 2.3 to 2.7), cerium oxide (CeO ₂ , refractive index: 1.95 to 2.20), tin oxide (SnO ₂₎ , Refractive index: 2.00), aluminum zinc oxide (AZO, refractive index: 1.9) 2.00), gallium zinc oxide (GZO, refractive index: 1.90 to 2.00), zinc antimonate (ZnSb ₂ O _6, refractive index: 1.9 to 2.0), zinc oxide (ZnO , Refractive index: 1.90), yttrium oxide (Y ₂ O ₃ , refractive index: 1.87), and the like. These high refractive index fine particles may be used alone or in combination of two or more.

The high refractive index fine particles may be surface-treated. By surface-treating the high refractive index fine particles, the affinity with the binder resin and the solvent is improved, the dispersion of the high refractive index fine particles becomes uniform, and the aggregation of the high refractive index fine particles hardly occurs, so the brightness improving layer Reduction in light transmittance, applicability of the composition for improving the brightness layer, and reduction in coating strength of the composition for improving the brightness layer can be suppressed.
Examples of the surface-treated high refractive index fine particles include those described in JP2013-142817A.

  The high refractive index fine particles may be reactive fine particles having a photocurable group on the surface thereof.

The average particle diameter of the high refractive index fine particles may be such that it can form a brightness improving layer having a uniform thickness, for example, preferably in the range of 5 nm to 200 nm, and more preferably in the range of 5 nm to 100 nm, In particular, it is preferably within a range of 10 nm to 80 nm. When the average particle diameter of the high refractive index fine particles is in the above range, a good dispersed state of the high refractive index fine particles can be obtained without impairing the light transmittance of the brightness improving layer. In addition, as long as the average particle diameter of the high refractive index fine particles is within the above range, the average particle diameter may be any of the primary particle diameter and the secondary particle diameter, and the high refractive index fine particles are connected in a chain. May be.
Here, the average particle diameter of the high refractive index fine particles refers to the average value of 20 particles observed by a transmission electron microscope (TEM) photograph of the cross section of the brightness enhancement layer.

  The shape of the high refractive index fine particles is not particularly limited, and examples thereof include spheres, chains, and needles.

  The content of the binder resin and the high refractive index fine particles in the brightness improving layer is appropriately set so that the refractive index of the brightness improving layer satisfies the above-described refractive index. For example, the refractive index of the entire brightness enhancement layer can be adjusted by adjusting the content of the high refractive index fine particles.

When an ultraviolet curable resin is used as the binder resin, the brightness enhancement layer may contain a photopolymerization initiator. As a photoinitiator, it can select from a general thing suitably.
Moreover, the brightness enhancement layer may contain various additives according to desired physical properties. Additives include, for example, dispersion aids, weatherability improvers, wear resistance improvers, polymerization inhibitors, crosslinkers, infrared absorbers, adhesion improvers, antioxidants, leveling agents, thixotropy imparting agents, cups A ring agent, a plasticizer, an antifoamer, a filler, etc. are mentioned.

The brightness enhancement layer of this aspect may be a single layer or a multilayer body in which the first brightness enhancement layer and the second brightness enhancement layer are laminated in order from the transparent substrate side. When the brightness enhancement layer is the multilayer body described above, the refractive index of the first brightness enhancement layer and the second brightness enhancement layer may be higher than the refractive index of the transparent substrate and different from the refractive index of the colored layer. The refractive index is preferably higher than the refractive index of the colored layer.
In addition, when a brightness improving layer is arrange | positioned on the whole surface between a transparent substrate, a colored layer of multiple colors, and a light shielding layer so that it may mention later, the brightness improving layer of this aspect is made into a multilayer body, A 1st brightness improving layer and the 1st (2) By reducing the refractive index of the brightness enhancement layer higher than the refractive index of the transparent substrate and lower than the refractive index of the light shielding layer, the effect of reducing external light reflection at the light shielding layer can be further improved. The magnitude relationship between the refractive indexes of the first brightness enhancement layer and the second brightness enhancement layer can be set as appropriate.

(2) Second Embodiment The brightness improving layer of this embodiment has a refractive index which is higher than the refractive index of the transparent substrate and is different from the refractive index of at least one colored layer (hereinafter, referred to as a specific colored layer) among a plurality of colored layers. It is a layer containing a resin or an inorganic material exhibiting a rate.

In this aspect, since the resin itself contained in the brightness enhancement layer exhibits a refractive index that is higher than that of the transparent substrate and different from at least the specific colored layer, the brightness enhancement layer can exhibit a specific refractive index. is there. Therefore, the brightness improving layer of this aspect does not need to separately contain fine particles having a refractive index different from that of the above resin. Similarly, in the case where the brightness improving layer is a layer containing an inorganic material, it is not necessary to separately contain fine particles having a refractive index different from that of the inorganic material.
Therefore, the brightness enhancement layer of this embodiment is a layer that does not contain fine particles, that is, a resin layer formed of a resin that is higher than the transparent substrate and has a refractive index different from that of the specific colored layer, or an inorganic material. An inorganic layer which has a refractive index higher than that of a transparent substrate and different from the refractive index of a specific colored layer.

  As the resin or inorganic material used for the brightness improving layer of the present embodiment, it is possible to form a brightness improving layer having light transmittance, a refractive index higher than that of the transparent substrate, and a refractive index different from at least a specific colored layer. Any material can be used. When the brightness improving layer is disposed also between a light shielding layer described later and the transparent substrate, the resin or the inorganic material is light transmissive and has a refractive index higher than that of the transparent substrate, and the refractive index of the light shielding layer The material may be any material that can form a brightness improving layer having a refractive index lower than the refractive index. Hereinafter, each material used for the brightness improvement layer of this aspect is demonstrated.

(A) Resin When the brightness enhancement layer of this embodiment is a resin layer, the resin may be any resin that can obtain a brightness enhancement layer having desired light transmittance and a specific refractive index. The above-mentioned resin is preferably a cured resin cured by irradiation of ionizing radiation such as heat or ultraviolet light or electron beam, and examples thereof include thermosetting resins and ionizing radiation curable resins. Further, as the ionizing radiation curable resin, an ultraviolet curable resin and an electron beam curable resin can be mentioned. Specifically, examples of the resin include triazine resin, acrylic resin, episulfide resin, thiourethane resin, polycarbonate, (urethane) methacrylate, (epoxy) methacrylate, diallyl carbonate, diallyl phthalate resin, sol gel resin and the like. It is done.
In addition, commercially available products include Hypertech UR-series, HR-series, HX-series and HT-series, which are high-refractive index coating materials of Nissan Chemical Industries, and high-refractive index coating materials of Sigma-Aldrich. Certain zirconium acrylates, hafnium acrylates, and high refractive index polymers based on aromatic or brominated aromatic monomers can be used.

When using an ultraviolet curable resin as the resin, the brightness improving layer may contain a photopolymerization initiator. As a photoinitiator, it can select from a general thing suitably.
When the brightness improving layer is formed of the above-mentioned resin, the brightness improving layer may contain various additives according to the desired physical properties. The additive can be the same as the additive described in the section “(1) First embodiment”, and thus the description thereof is omitted here.

  When the brightness enhancement layer of this embodiment is a resin layer, fine particles having a refractive index different from that of the resin are not contained. Here, fine particles having a refractive index different from that of the above-mentioned resin are not particularly limited, and examples thereof include fine particles of metal oxide such as titanium oxide and zirconium oxide.

(B) Inorganic material When the brightness enhancement layer of this embodiment is an inorganic layer, the inorganic material can be formed into a film, and a brightness enhancement layer having desired light transmittance and a specific refractive index can be obtained. What is necessary is just a thing, For example, metal compounds, such as a metal oxide, metal nitride, and metal oxynitride, and a metal are mentioned. Among these, metal oxides are preferable from the viewpoint of light transmittance. Examples of the metal oxide include indium tin oxide (ITO), niobium oxide, silicon oxide, aluminum oxide, aluminum oxide alloy, zinc oxide, titanium oxide, zirconium oxide, tin oxide, antimony oxide, cerium oxide, and indium zinc oxide. (IZO), antimony tin oxide (ATO), phosphorus tin compound (PTO), aluminum zinc oxide (AZO), gallium zinc oxide (GZO), zinc antimonate, barium titanate and the like. Moreover, as a metal nitride and metal oxynitride, silicon nitride, silicon oxynitride, etc. are mentioned, for example. Among these, indium tin oxide (ITO) is preferable. This is because ITO is a general-purpose material, so that existing equipment can be used and manufacturing costs can be reduced.
Of the above metal oxides, even if the refractive index of the metal oxide itself is not within the range of the refractive index of the high refractive index layer, the refractive index of the high refractive index layer can be adjusted by adjusting the composition, for example. You can control the rate. Further, among the above-described metal oxides, there are also substances which can appropriately change the refractive index depending on the film forming conditions. For example, there are a method of changing the oxygen partial pressure and a method of changing the temperature of the transparent substrate.

(C) Others As described above, the brightness enhancement layer of this embodiment does not contain fine particles having a refractive index different from that of the resin or inorganic material forming the brightness enhancement layer. Here, that the brightness enhancement layer does not contain fine particles having a refractive index different from that of the resin or the inorganic material means that the content of the fine particles in the brightness enhancement layer is 0.1% by mass or less. In particular, the content of fine particles in the brightness enhancement layer is preferably zero.

  The brightness improving layer of this aspect may be a single layer, or may be a multilayer body in which a first brightness improving layer and a second brightness improving layer are sequentially stacked from the transparent substrate side. In addition, about the detail in case a brightness improving layer is a multilayer body, since it is the same as the content demonstrated by the term of "(1) 1st aspect", description here is abbreviate | omitted.

(3) Others The brightness enhancement layer is light transmissive. As for the light transmittance of the luminance improving layer, the total light transmittance is preferably 70% or more, and more preferably 80% or more, particularly 90% or more.
Here, the total light transmittance of the brightness improving layer can be measured in accordance with JIS K 7361-1 (Plastic-Test Method of Total Light Transmittance of Transparent Material).

The arrangement mode of the brightness improving layer may be any mode as long as it is arranged between the transparent substrate and the colored layer of at least one of the colored layers of plural colors, and in particular, it is arranged between the transparent substrate and the blue colored layer It is preferable to set it as the arrangement aspect.
As a specific arrangement mode of the brightness enhancement layer, as illustrated in FIG. 1, the brightness enhancement layer 3 is disposed only between the transparent substrate 2 and the specific colored layer 5 (blue colored layer 5B) of a specific color. It may be an aspect (first aspect), and as shown in FIG. 5A, a brightness improving layer corresponding to each of the colored layers 5R, 5B, 5B between the transparent substrate 2 and the colored layers 5 of a plurality of colors. The aspect (2nd aspect) by which 3R, 3G, 3B is arrange | positioned may be sufficient. When a brightness enhancement layer with a thickness and refractive index adjusted according to color is arranged for each colored layer, it is possible to improve the transmitted light brightness in each colored layer. The overall brightness can be improved.

In addition, as illustrated in FIG. 5B as an arrangement aspect of the luminance improvement layer, a single luminance improvement layer 3 is disposed on the entire surface between the transparent substrate 2 and the colored layers 5R, 5B, and 5B of each color. The mode (third mode) may be used. In the case where the arrangement mode of the brightness enhancement layer is the third mode, it is sufficient that the transmitted light brightness can be improved at least for the light transmitted through the blue colored layer, and the brightness enhancement layer increases the amount of transmitted light in the blue colored layer. It is preferred to have a specific thickness and refractive index. The specific thickness and refractive index of the brightness enhancement layer are as described above.
Note that light transmitted through a colored layer other than the blue colored layer is allowed as long as the transmitted light luminance is reduced by the luminance enhancement layer as long as it does not hinder display.

In the present invention, the brightness enhancement layer may be disposed between the transparent substrate and the light shielding layer in addition to the transparent substrate and the colored layer. For example, as illustrated in FIG. 6, the brightness enhancement layer 3 is provided between the transparent substrate 2 and a specific colored layer 5 (blue colored layer 5 </ b> B in FIG. 6), and between the transparent substrate 2 and the light shielding layer 4. As shown in FIG. 7, the brightness enhancement layer 3 may be disposed on the entire surface between the transparent substrate 2 and the colored layers 5 and the light shielding layers 4. .
When the brightness enhancement layer is disposed between the transparent substrate and the light shielding layer, the brightness enhancement layer may be disposed only in the pixel light shielding portion of the light shielding layer, or may be disposed only in the frame light shielding portion. It is preferable that the light shielding part and the frame light shielding part are disposed in both.
Among them, in the present invention, it is preferable that the above-mentioned brightness improving layer be disposed on the entire surface between the transparent substrate and the colored layers of a plurality of colors and the light shielding layer. The reason is as follows.
In the conventional color filter, one of the causes of external light reflection in the light shielding layer is that the refractive index of the light shielding layer is higher than the refractive index of the transparent substrate, and the refractive index difference is large. Therefore, by arranging a brightness enhancement layer between the transparent substrate and the light shielding portion, the reflected light from the interface between the transparent substrate and the brightness enhancement layer interferes with the reflected light from the interface between the brightness enhancement layer and the light shielding layer. This is because it is possible to reduce external light reflection at the light shielding layer by the light interference effect. At this time, by setting the refractive index of the luminance improving layer to be higher than the refractive index of the transparent substrate and lower than the refractive index of the light shielding layer, the external light reflection reducing effect of the light shielding layer by the luminance improving layer is more easily exhibited. .
In addition, in the case of the brightness enhancement layer of the first aspect, it contains a binder resin and highly refractive fine particles, and has less diffuse reflection than a light-shielding resin layer containing a conventional color material. When a filter is used for a display device, it is possible to suppress the occurrence of whitening and to improve display quality. On the other hand, in the case of the brightness improving layer of the second embodiment, since the fine particles are not contained, the diffuse reflection by the fine particles does not occur. Therefore, when the color filter of the present invention is used for a display device, the occurrence of whitening is suppressed. The contrast can be increased and the display quality can be improved.
In this way, by arranging the brightness enhancement layer between the transparent substrate and the light shielding layer, in addition to the effect of improving the brightness of the colored layer by the brightness enhancement layer, reflection from the interface between the transparent substrate and the brightness enhancement layer. This is because it is possible to interfere with light reflected from the interface between the brightness enhancement layer and the light shielding layer, and to obtain an effect of reducing reflection of external light at the light shielding layer due to the light interference effect.
In addition, by arranging a brightness enhancement layer on the entire surface between the transparent substrate and the colored layers and light-shielding layers of the plurality of colors, patterning for providing the brightness enhancement layer for each colored layer is not necessary, and it is easy to manufacture a color filter. There is also a manufacturing advantage that can be achieved.
When the brightness improving layer is disposed on the entire surface between the transparent substrate and the colored layers and the light shielding layer of a plurality of colors, it is more preferable that the refractive index of the brightness improving layer is lower than the refractive index of the light shielding layer. preferable.

The rate of improvement in transmitted light luminance (hereinafter referred to as luminance improvement rate) by arranging the luminance enhancement layer is not particularly limited, but at least the transmitted light luminance in the case where the luminance enhancement layer is not arranged in the blue colored layer. On the other hand, the luminance improvement rate due to the arrangement of the luminance enhancement layer is preferably 3% or more, and more preferably 5% or more.
The transmitted light luminance is defined by the Y value in the CIE color system chromaticity. For example, using the “microspectrophotometer OSP-SP200” manufactured by Olympus Corporation, the standard by the International Commission on Illumination CIE vertically from the glass substrate side of the color filter. A Y value measured with respect to the transmitted light that is applied to the back side by the light of the light source C.
In order to eliminate the influence of the difference in refractive index from the air interface, the Y value is usually the color filter and a separately prepared counter substrate (glass substrate) on the side where the colored layers of the color filter are arranged. It is measured with the surface disposed on the counter substrate side and matching oil (glycerin) disposed between the color filter and the counter substrate.
Moreover, when the brightness improvement layer which has the thickness and refractive index corresponding to every colored layer is arrange | positioned, it is preferable to show the same brightness improvement rate also about colored layers other than blue.

The method for forming the brightness enhancement layer is appropriately selected according to the arrangement mode, material, and the like of the brightness enhancement layer. For example, the method for apply | coating the composition for brightness enhancement layers containing a desired material to the desired position on a transparent substrate, and hardening it is mentioned.
As the composition for brightness enhancement layer, if the brightness enhancement layer of the first aspect is formed, it contains, for example, a resin component, high refractive index fine particles, various additives, and a solvent. In the case of forming the brightness enhancement layer of the second embodiment, the resin component, various additives, and a solvent are contained.
The solvent is not particularly limited as long as each component can be dissolved or dispersed. For example, JP 2013-142817 A, JP 2012-150226 A, JP 2011-170208 A, and the like. And those used for forming the high refractive index layer described in (1).

When the brightness improving layer is disposed only in a specific colored layer or in each colored layer, as a method of applying the composition for a brightness improving layer, for a brightness improving layer at a predetermined position on a transparent substrate by an inkjet method or the like. A method of discharging the composition, a gravure printing method, an offset printing method, a printing method such as a silk screen printing method, or the like can be used.
Moreover, after apply | coating the composition for brightness improving layers to the whole surface of a transparent substrate by the method mentioned later, making it harden and forming a brightness improving layer, patterning only with a specific colored layer by patterning by photolithography A brightness enhancement layer can be disposed in each colored layer. At this time, the brightness enhancement layer may be patterned using the light shielding layer as a mask.
On the other hand, when disposed on the entire surface between the transparent substrate and the colored layers and the light-shielding layer, the method for applying the composition for improving the brightness layer includes a die coating method, a spin coating method, a dip coating method, a roll coating method, etc. The method of can be used.
After application of the composition for brightness enhancement layer, it may be dried to remove the solvent.

The curing method varies depending on the type of the resin component, and examples thereof include irradiation with ionizing radiation such as heat or ultraviolet rays or electron beams. When the brightness enhancement layer of the first aspect is formed, it is preferable to use an inert gas atmosphere, for example, a nitrogen gas atmosphere, in order to suppress curing inhibition by oxygen when the coating film is cured.
Curing conditions vary depending on the type of resin component, but are described in, for example, JP2013-142817A, JP2012-150226A, and the like if the brightness enhancement layer of the first aspect is formed. Conditions can be applied.

On the other hand, when the brightness enhancement layer of the second embodiment is an inorganic layer, the brightness enhancement layer can be formed by, for example, a method of forming the brightness enhancement layer in a pattern directly on the transparent substrate by mask vapor deposition, After forming the brightness improving layer on the entire surface, a method of patterning by photolithography can be used. The brightness enhancement layer may be patterned using the light shielding layer as a mask.
When the brightness improving layer is disposed on the entire surface between the transparent substrate and the colored layers and the light shielding layers of plural colors, for example, the PVD method such as sputtering method, ion plating method, vacuum evaporation method, CVD method, etc. A method of forming the entire surface of the transparent substrate can be used.

2. Light-shielding layer The light-shielding layer in the present invention is formed in a pattern on a transparent substrate.
In addition, the light shielding layer is formed in the display area and includes a pixel classification light shielding section that segments pixels and a frame light shielding section formed in the non-display area.

As the light shielding layer, for example, a material in which a black color material is dispersed in a binder resin is used.
The binder resin is appropriately selected according to the method for forming the light shielding layer. In the case of the photolithography method, as the binder resin, for example, a photosensitive resin having a reactive vinyl group such as acrylate, methacrylate, polyvinyl cinnamate, or cyclized rubber is used. In the case of a printing method or an inkjet method, examples of the binder resin include polymethyl methacrylate resin, polyacrylate resin, polycarbonate resin, polyvinyl alcohol resin, polyvinyl pyrrolidone resin, hydroxyethyl cellulose resin, carboxymethyl cellulose resin, polyvinyl chloride resin, melamine Examples thereof include resins, phenol resins, alkyd resins, epoxy resins, polyurethane resins, polyester resins, maleic acid resins, polyamide resins and the like.

Examples of the black color material include those generally used for a light shielding layer of a color filter, and any of pigments and dyes can be used. For example, carbon black, titanium black and the like can be mentioned.
The content of the black color material in the light shielding layer may be the same as that of a general light shielding layer in a color filter as long as a desired light shielding property can be obtained.

  Further, the light shielding layer may contain a photopolymerization initiator, a sensitizer, a coating property improver, a development improver, a crosslinking agent, a polymerization inhibitor, a plasticizer, a flame retardant, and the like, if necessary. .

  The thickness of the light shielding layer can be the same as the thickness of a general light shielding layer in a color filter, and can be set, for example, in the range of 0.5 μm to 2.0 μm.

  The shape of the opening of the light shielding layer is not particularly limited, and examples thereof include one in which the arrangement of the colored layers is changed, such as a stripe shape, a V shape, or a delta arrangement.

The light shielding layer may be a single layer as illustrated in FIG. 1 and the like, or may be a multilayer. Examples of the light shielding layer of the multilayer body include those in which a reflection control layer and a light shielding resin layer are laminated in order from the transparent substrate side. With such a layer configuration, the reflection control layer can further reduce external light reflection at the light shielding layer. When the color filter of the present invention is used in a display device, the non-display area is not displayed when the image is not displayed. The reflected light luminance at the frame light shielding portion and the average reflected light luminance at the colored layers of the plurality of colors and the pixel classification light shielding portion in the display area can be further reduced. As a result, when the image is not displayed, the difference between the reflected light luminance at the frame light shielding portion in the non-display area and the average reflected light luminance at the colored layers and pixel segmenting light shielding portions in the display area can be reduced. It is possible to improve the appearance when images are not displayed.
Examples of the reflection control layer include a colored resin layer containing a color material such as a red color material, a green color material, a blue color material, a yellow color material, a black color material, and the like. A colored layer constituting the filter or a colored resin layer containing a black color material can be used. The color material contained in the reflection control layer may be one type or two or more types.

When the reflection control layer is a colored layer constituting a color filter, the configuration is the same as that of the colored layer.
When the reflection control layer is a colored resin layer containing a black color material, the black color material is the same as the black color material used for the single light-shielding layer, and the binder resin used for the colored resin layer is a single layer It can be the same as the binder resin used for the light shielding layer.
The light shielding resin layer can be the same as the single light shielding layer.

  The method for forming the light shielding layer is not particularly limited as long as the light shielding layer can be formed in a pattern on the transparent substrate or the brightness enhancement layer. Examples thereof include a photolithography method, a printing method, and an ink jet method. be able to.

3. Colored layer The colored layer in this invention is formed in the opening part of the said light shielding layer. Further, in the present invention, a brightness improving layer having colored layers of a plurality of colors, wherein at least one of the colored layers among the colored layers of the plurality of colors has a specific thickness and a refractive index with the transparent substrate. Is arranged.

  Examples of the color of the colored layer include one or a combination of two or more selected from the group consisting of red, green, blue, yellow, cyan, and magenta. Moreover, in addition to said colored layer, you may use a white (colorless) layer as a colored layer. Specifically, the color of the coloring layer is red, green, blue three colors, red, green, blue, yellow four colors, red, green, blue, yellow, cyan five colors, red, green, blue, It can be four colors such as white.

The colored layer is, for example, a color material dispersed in a binder resin.
Examples of the color material include pigments and dyes of each color. Examples of the red color material used in the red colored layer include perylene pigments, lake pigments, azo pigments, quinacridone pigments, anthraquinone pigments, anthracene pigments, and isoindoline pigments. Examples of the green color material used in the green coloring layer include phthalocyanine pigments such as halogen polysubstituted phthalocyanine pigments or halogen polysubstituted copper phthalocyanine pigments, triphenylmethane basic dyes, isoindoline pigments, and isoindolinones. Based pigments and the like can be mentioned. Examples of the blue color material used for the blue colored layer include copper phthalocyanine pigments, anthraquinone pigments, indanthrene pigments, indophenol pigments, cyanine pigments, dioxazine pigments and the like. These pigments and dyes may be used alone or in combination of two or more.
As the binder resin, for example, a photosensitive resin having a reactive vinyl group such as acrylate, methacrylate, polyvinyl cinnamate, or cyclized rubber is used.
The colored layer may contain a photopolymerization initiator and, if necessary, a sensitizer, a coatability improver, a development improver, a crosslinking agent, a polymerization inhibitor, a plasticizer, a flame retardant, and the like.

The arrangement of the colored layers is not particularly limited, and may be a known arrangement such as a stripe type, a mosaic type, a triangle type, or a four-pixel arrangement type.
There may or may not be a gap between adjacent colored layers.

The thickness of the colored layer can be the same as the thickness of a general colored layer in a color filter, and can be set, for example, in the range of 1 μm to 5 μm.
As a method for forming the colored layer, any method can be used as long as a plurality of colored layers can be arranged on the same plane, and examples thereof include a photolithography method, an inkjet method, and a printing method.

Further, a white layer that does not contain the color material but contains the binder resin and transmits light from the light source of the display device may be formed on the same plane on which the colored layer is formed.
The thickness and formation method of the white layer are the same as those of the colored layer.

4. Transparent Substrate The transparent substrate in the present invention supports the above-mentioned brightness improving layer, light shielding layer, colored layer and the like.
As the transparent substrate, those generally used for color filters can be used, and for example, non-flexible inorganic substrates such as quartz glass, Pyrex (registered trademark) glass, synthetic quartz plates and the like, and transparent Examples thereof include a resin substrate having flexibility such as a resin film and an optical resin plate. Among them, it is preferable to use an inorganic substrate, and it is preferable to use a glass substrate among inorganic substrates. Furthermore, it is preferable to use an alkali-free type glass substrate among the glass substrates. The alkali-free type glass substrate is excellent in dimensional stability and workability in high-temperature heat treatment, and contains no alkali component in the glass, so it is suitable for use in color filters for liquid crystal display devices using the active matrix method. Because you can.

5. Other Configurations The color filter of the present invention may have other configurations as needed, in addition to the above-mentioned transparent substrate, brightness improving layer, light shielding layer and colored layer.

In the present invention, an overcoat layer may be formed on the colored layer. The surface of the color filter can be flattened by the overcoat layer.
The material of the overcoat layer is not particularly limited as long as it can flatten the surface on which the colored layer is formed, and it can be the same as the overcoat layer generally used for color filters. Any of organic materials and inorganic materials can be used. When the overcoat layer is composed of an inorganic material, barrier properties can be imparted.
The thickness of the overcoat layer and the method for forming the overcoat layer can be the same as the overcoat layer generally used for color filters.

  For example, a transparent electrode layer or an alignment film may be formed on the overcoat layer, and a spacer may be formed on the inter-pixel light shielding portion. The transparent electrode layer, the alignment film, and the spacer can be the same as those generally used for a liquid crystal display device.

6. Applications The color filter of the present invention can be used suitably for display devices such as liquid crystal display devices and organic EL display devices because it can improve the light extraction efficiency and display luminance in the colored layer, particularly the blue colored layer. . Among them, in the case of having the luminance improving layer of the first aspect, the color filter of the present invention can be suitably used for an organic EL display device. On the other hand, in the case of having the brightness enhancement layer of the second aspect, the color filter of the present invention can be suitably used for a liquid crystal display device.

  In addition, when the brightness improving layer is disposed also between the transparent substrate and the light shielding layer, external light reflection at the light shielding portion can be reduced, so that it can be used more suitably for the above display device. it can. Above all, by using the color filter of the present invention for the organic EL display device, it is not necessary to use a circularly polarizing plate for reducing external light reflection. Therefore, it is possible to suppress a decrease in light use efficiency due to the circularly polarizing plate and achieve high luminance.

B. Display device The display device of the present invention includes a transparent substrate, a light shielding layer formed in a pattern on the transparent substrate, and colored layers of plural colors formed in the opening of the light shielding layer, and the transparent A brightness improving layer having a specific thickness and a refractive index is disposed between the substrate and the colored layer of at least one of the colored layers of the plurality of colors, and the refractive index of the brightness improving layer is at least the transparent. It is characterized by comprising a color filter which is higher than the refractive index of the substrate and different from the refractive index of the colored layer of the one color.

According to the present invention, by providing the above-described color filter, it is possible to increase the amount of light transmitted through the specific colored layer in which the brightness enhancement layer is disposed, and to improve the display brightness in the display area of the display device. It is. In particular, blue display luminance can be improved.
Further, in the above-described color filter, when a brightness enhancement layer is disposed between the transparent substrate and the light shielding layer in addition to the transparent substrate and the colored layer, external light reflection at the light shielding layer can be reduced. It is possible to improve display quality.
The details of the color filter in the present invention are the same as the contents described in the section “A. Color filter”, and thus the description thereof is omitted here.

  Examples of the display device of the present invention include a liquid crystal display device and an organic EL display device.

When the display device of the present invention is a liquid crystal display device, the liquid crystal display device has, for example, the above-described color filter, a counter substrate, and a liquid crystal layer disposed between the color filter and the counter substrate. In addition, it is preferable that the color filter used at this time has the brightness | luminance improvement layer of a 2nd aspect.
A transparent electrode layer and an alignment film can be formed on the opposing surfaces of the color filter and the opposing substrate. A TFT element or the like can be formed on the counter substrate. The counter substrate is appropriately selected according to the driving method of the liquid crystal display device. Examples of the liquid crystal used in the liquid crystal layer include nematic liquid crystal and smectic liquid crystal, and are appropriately selected according to the driving method of the liquid crystal display device.
About each member which comprises a liquid crystal display device, it can be set as the same as a general liquid crystal display device.

When the display device of the present invention is an organic EL display device, the organic EL display device has, for example, the above-described color filter and an organic EL element substrate in which an organic EL element is formed on a support substrate. In addition, it is preferable that the color filter used at this time has the brightness | luminance improvement layer of a 1st aspect.
The organic EL element has, for example, a back electrode layer formed on a support substrate, an organic EL layer formed on the back electrode layer, including at least a light emitting layer, and a transparent electrode layer formed on the organic EL layer. . The organic EL layer can have a hole injection layer, a hole transport layer, an electron injection layer, an electron transport layer, and the like in addition to the light emitting layer. The space between the color filter and the organic EL element substrate can be filled with, for example, a resin.
About each member which comprises an organic electroluminescence display, it can be set as the same as a general organic electroluminescence display.

  The present invention is not limited to the above embodiment. The above embodiment is an exemplification, and it has substantially the same configuration as the technical idea described in the claims of the present invention, and any one having the same function and effect can be used. It is included in the technical scope of the invention.

  Hereinafter, the present invention will be described in more detail with reference to Examples and Comparative Examples.

Example 1
(Preparation of curable resin composition A)
The polymerization tank is charged with 63 parts by weight of methyl methacrylate (MMA), 12 parts by weight of acrylic acid (AA), 6 parts by weight of 2-hydroxyethyl methacrylate (HEMA), and 88 parts by weight of diethylene glycol dimethyl ether (DMDG). After stirring and dissolving, 7 parts by weight of 2,2'-azobis (2-methylbutyronitrile) was added and uniformly dissolved. Then, it stirred at 85 degreeC under nitrogen stream for 2 hours, and also was made to react at 100 degreeC for 1 hour. Further, 7 parts by weight of glycidyl methacrylate (GMA), 0.4 parts by weight of triethylamine, and 0.2 parts by weight of hydroquinone are added to the obtained solution, and the mixture is stirred at 100 ° C. for 5 hours to obtain a copolymer resin solution ( 50% solids was obtained.

Next, the following materials were stirred and mixed at room temperature to obtain a curable resin composition A.
<Composition of curable resin composition A>
-Copolymer resin solution (solid content 50%): 16 parts by weight-Dipentaerythritol pentaacrylate (Sartomer SR399): 24 parts by weight-Orthocresol novolac type epoxy resin (Oka Chemical Shell Epoxy Epicoat 180S70): 4 parts by weight Part: 2-Methyl-1- (4-methylthiophenyl) -2-morpholinopropan-1-one: 4 parts by weight Diethylene glycol dimethyl ether: 52 parts by weight

(Formation of the brightness improving layer A)
The curable resin composition A, the titanium oxide fine particle dispersion, and the zirconia fine particle dispersion are mixed so as to have a refractive index of 1.74 and mixed to obtain a brightness enhancement layer having a refractive index of 1.74. A composition was prepared. Next, a composition for a brightness enhancement layer is applied by a spin coater on a glass substrate having a refractive index of about 1.5, dried at 100 ° C. for 3 minutes, exposed with a super high pressure mercury lamp, and has a thickness of 27 nm. An enhancement layer A was formed.

(Formation of light shielding layer)
The components of the following amounts were mixed and sufficiently dispersed by a sand mill to prepare a black pigment dispersion.
<Composition of Black Pigment Dispersion>
Black pigment (Mitsubishi Chemical Co., Ltd. # 2600): 20 parts by weight Polymer dispersion material (Big Chemie Japan, Disperbyk 111): 16 parts by weight Solvent (diethylene glycol dimethyl ether): 64 parts by weight

Next, the following components were sufficiently mixed to obtain a light shielding layer composition.
<Composition of composition for light shielding layer>
-Black pigment dispersion: 50 parts by weight-Curable resin composition A: 20 parts by weight-Diethylene glycol dimethyl ether: 30 parts by weight

  The composition for a light shielding layer was applied by a spin coater on the substrate on which the brightness improving layer A was formed, and dried at 100 ° C. for 3 minutes. The coated film of the composition for a light shielding layer is exposed to a light shielding pattern with an ultrahigh pressure mercury lamp and then developed with a 0.05 wt% potassium hydroxide aqueous solution, and then the substrate is left to stand in an atmosphere of 230 ° C. for 30 minutes. A heat treatment was performed to form a light shielding layer having an optical density of 4.0, a film thickness of 3 μm, and a pixel division light shielding portion and a frame light shielding portion. The refractive index of the light shielding layer was 1.9.

(Formation of red colored layer)
On the board | substrate with which the light shielding layer was formed, the red curable resin composition of the following composition was apply | coated with the spin coating method, and it dried for 3 minutes in 70 degreeC oven after that. Next, a photomask is placed at a distance of 100 μm from the coating film of the red curable resin composition, and an ultraviolet ray is applied only to the region corresponding to the red colored layer forming region using a 2.0 kW ultrahigh pressure mercury lamp by a proximity aligner. For 10 seconds. Subsequently, it was immersed in 0.05 wt% potassium hydroxide aqueous solution (liquid temperature 23 degreeC) for 1 minute, and alkali development was carried out, and only the uncured part of the coating film of a red curable resin composition was removed. Thereafter, the substrate was left to stand in an atmosphere of 230 ° C. for 15 minutes to perform heat treatment to form a red colored layer in a pattern. The formed thickness of the red colored layer was 2.0 μm, and the refractive index was 1.60.
<Composition of Red Curable Resin Composition>
C. I. Pigment red 177: 3 parts by weight, C.I. I. Pigment Red 254: 4 parts by weight-Polysulfonic acid type polymer dispersant: 3 parts by weight-Curable resin composition A: 23 parts by weight--3-methoxybutyl acetate: 67 parts by weight

(Formation of green colored layer)
Next, using the green curable resin composition of the following composition, the applied film thickness is changed in the same step as the formation of the red colored layer so that the formed film thickness is 2.0 μm, the green colored layer Were formed in a pattern. The resulting green colored layer had a refractive index of 1.59.
<Composition of Green Curable Resin Composition>
C. I. Pigment green 58: 7 parts by weight C.I. I. Pigment Yellow 138: 1 part by weight, polysulfonic acid type polymer dispersant: 3 parts by weight, curable resin composition A: 22 parts by weight, and 3-methoxybutyl acetate: 67 parts by weight

(Formation of a blue colored layer)
Furthermore, using the blue curable resin composition having the following composition, in the same process as the formation of the red colored layer, the coating film thickness is changed so that the formed film thickness becomes 2.0 μm. Formed in a pattern. The resulting blue colored layer had a refractive index of 1.58.
<Composition of Blue Curable Resin Composition>
C. I. Pigment Blue 15: 6: 5 parts by weight-Polysulfonic acid type polymer dispersant: 3 parts by weight-Curable resin composition A: 25 parts by weight--3-methoxybutyl acetate: 67 parts by weight

(Formation of overcoat layer)
On the board | substrate in which the colored layer of each color was formed, said curable resin composition A was apply | coated and dried by the spin coating method, and the coating film of 2 micrometers of dry coating films was formed. A photomask was placed at a distance of 100 μm from the coating film, and ultraviolet rays were irradiated for 10 seconds only to the area corresponding to the formation area of the overcoat layer using a 2.0 kW ultra-high pressure mercury lamp with a proximity liner. Subsequently, it was immersed in 0.05 wt% potassium hydroxide aqueous solution (liquid temperature 23 degreeC) for 1 minute, and alkali development was carried out, and only the uncured part of the coating film of the curable resin composition A was removed. Thereafter, the substrate was left to stand in an atmosphere at 230 ° C. for 15 minutes to perform a heat treatment to form an overcoat layer. Thus, a color filter was obtained.

Example 2
A color filter was produced in the same manner as in Example 1 except that the brightness enhancement layer B was formed as follows instead of the brightness enhancement layer A.
(Formation of the brightness improving layer B)
The curable resin composition A, the titanium oxide fine particle dispersion, and the zirconia fine particle dispersion are mixed and adjusted so that the refractive index is 1.61, and the luminance enhancement layer having a refractive index of 1.61 is mixed. The composition was prepared. Next, the composition for a brightness enhancement layer is applied by a spin coater on a glass substrate having a refractive index of about 1.5, dried at 100 ° C. for 3 minutes, exposed with an ultrahigh pressure mercury lamp, and has a thickness of 40 μm. The enhancement layer B was formed.

[Comparative example]
A color filter was produced in the same manner as in Example 1 except that the brightness enhancement layer was not formed.

[Evaluation]
An evaluation sample was prepared by the following method using each color filter obtained in the examples and comparative examples.
The color filter and the opposing substrate (glass substrate having a refractive index of about 1.5) prepared separately are disposed such that the surface on which the colored layer of each color of the color filter is disposed is the opposing substrate side. A matching oil (glycerin) was placed between the opposing substrates to obtain a sample for evaluation.
For each evaluation sample, the light source of standard light source C according to the International Commission on Illumination CIE is applied vertically from the glass substrate side of the color filter using “Microspectroscopic light measurement device OSP-SP200” manufactured by Olympus, and The Y value at the CIE coloring system chromaticity was measured for the transmitted light transmitted, and the Y value was taken as the transmitted light luminance.
The ratio (%) of the transmitted light luminance Y (sample) in each color colored layer and the transparent substrate in the example to the transmitted light luminance Y (ref) in each color colored layer and the transparent substrate in the comparative example was calculated.
The results are shown in Table 1.

  By providing the brightness enhancement layer designed with a specific thickness and refractive index, it was confirmed that the transmitted light brightness was improved in the blue colored layer. That is, it was suggested that the increase in the amount of transmitted light in the blue colored layer was made possible by having the specific thickness and refractive index corresponding to the blue colored layer, and the light extraction efficiency was improved.

DESCRIPTION OF SYMBOLS 1 ... Color filter 2 ... Transparent substrate 3 ... Brightness improvement layer 4 ... Light-shielding layer 5 ... Colored layer 5R ... Red colored layer 5G ... Green colored layer 5B ... Blue colored layer 6 ... Pixel classification light-shielding part 7 ... Frame light-shielding part 11 ... Display area 12 ... Non-display area

Claims (3)

A transparent substrate;
A light shielding layer formed in a pattern on the transparent substrate;
A plurality of colored layers formed in the opening of the light shielding layer,
A brightness improving layer having a specific thickness and a refractive index is disposed between the transparent substrate and the colored layer of at least one of the colored layers of the plurality of colors,
The brightness enhancement layer is disposed only between the transparent substrate and the blue colored layer,
The color filter according to claim 1, wherein a refractive index of the brightness enhancement layer is at least higher than a refractive index of the transparent substrate and different from a refractive index of the colored layer of one color.   The color filter according to claim 1, wherein a refractive index of the brightness enhancement layer is higher than a refractive index of the colored layer of one color. A transparent substrate;
A light shielding layer formed in a pattern on the transparent substrate;
A plurality of colored layers formed in the opening of the light shielding layer,
A brightness improving layer having a specific thickness and a refractive index is disposed between the transparent substrate and the colored layer of at least one of the colored layers of the plurality of colors,
The brightness enhancement layer is disposed only between the transparent substrate and the blue colored layer,
A display device comprising a color filter in which the refractive index of the brightness improving layer is higher than the refractive index of at least the transparent substrate and different from the refractive index of the colored layer of one color.