WO2020195786A1

WO2020195786A1 - Color conversion substrate and display using same

Info

Publication number: WO2020195786A1
Application number: PCT/JP2020/010270
Authority: WO
Inventors: 神崎達也; 石田豊
Original assignee: 東レ株式会社
Priority date: 2019-03-27
Filing date: 2020-03-10
Publication date: 2020-10-01
Also published as: JPWO2020195786A1; TW202041650A

Abstract

This color conversion substrate is characterized by having a partition wall on a substrate and having, in a region partitioned by the partition wall, a green color conversion layer, a red color conversion layer, and a non-color conversion layer not including a phosphor, wherein the green color conversion layer and the red color conversion layer include light-emitting materials, and when Sg is the area of the green color conversion layer, Sr is the area of the red color conversion layer, and Sn is the area of the non-color conversion layer, Sg, Sr, and Sn satisfy the relationship of the following expressions (A) and (B). (A): Sn < Sg, (B): Sn < Sr

Description

Color conversion board and display using it

The present invention relates to a color conversion substrate and a display using the same.

There are many studies to apply the multi-color technology based on the color conversion method to liquid crystal displays, organic EL displays, lighting, and so on.

As a means for improving the color reproducibility of a liquid crystal display, a technique of using quantum dots made of inorganic semiconductor fine particles as a component of a color conversion composition has been proposed (see, for example, Patent Document 1).

Further, a color conversion method has been proposed as one of the methods for realizing multicolor light emission by using a self-luminous element such as an organic EL display or a micro LED display (see, for example, Patent Documents 2 and 3). The color conversion method is a method of expressing multiple colors by arranging a color conversion layer that absorbs light emitted from a self-luminous element and emits light having a wavelength distribution different from the absorption wavelength in front of the light emitting element. Since this method can use a light emitting element that emits a single color, it is easy to manufacture a display, and its development in a large screen display is being actively studied.

Japanese Unexamined Patent Publication No. 2011-241160 Japanese Unexamined Patent Publication No. 8-286033 International Publication No. 2010/092694

However, in a display based on the color conversion method, the organic light emitting material contained in the green color conversion layer and the red color conversion layer absorbs the blue light from the light source and converts it into green light and red light to display the color. There is a problem that the color conversion efficiency in the color conversion layer is low, and a display having a preferable chromaticity and sufficient brightness cannot be obtained. In order to improve the color conversion efficiency, it is preferable to use an organic light emitting material for the color conversion layer, but even with the color conversion methods described in Documents 2 and 3, from the viewpoint of achieving both preferable chromaticity and sufficient brightness, it is still possible. It was inadequate.

An object to be solved by the present invention is to provide a color conversion substrate capable of achieving both preferable chromaticity and sufficient brightness in a color conversion substrate used for an organic EL display, a micro LED display, or the like.

In order to solve the above-mentioned problems and achieve the object, the present invention has a green color conversion layer, a red color conversion layer, and a phosphor in a region having a partition wall on the substrate and partitioned by the partition wall. A color conversion substrate having a non-color conversion layer that does not include the green color conversion layer and the red color conversion layer, the green color conversion layer and the red color conversion layer include a light emitting material, the area of the green color conversion layer is Sg, and the area of the red color conversion layer. Is S, and when the area of the non-color conversion layer is Sn, Sg, Sr, and Sn are color conversion substrates that satisfy the relationship of the following formulas (A) and (B).
Formula (A) Sn <Sg
Equation (B) Sn <Sr

When the color conversion substrate according to the present invention is combined with a self-luminous light source, there is an effect that it is possible to achieve both preferable chromaticity and sufficient brightness.

FIG. 1 is a schematic cross-sectional view showing an example of a color conversion substrate and a display according to an embodiment of the present invention. FIG. 2 is a schematic cross-sectional view showing an example of a color conversion substrate and a display according to an embodiment of the present invention. FIG. 3 is a schematic top view showing an example of the shapes of the partition wall and the color conversion layer included in the color conversion substrate according to the embodiment of the present invention. FIG. 4 is a schematic top view showing an example of the shapes of the partition wall and the color conversion layer included in the color conversion substrate according to the embodiment of the present invention. FIG. 5 is a schematic top view showing an example of the shapes of the partition wall and the color conversion layer included in the color conversion substrate according to the embodiment of the present invention. FIG. 6 is a schematic top view showing an example of the shapes of the partition wall and the color conversion layer included in the color conversion substrate according to the embodiment of the present invention. FIG. 7 is a schematic top view showing an example of the shapes of the partition wall and the color conversion layer included in the color conversion substrate according to the embodiment of the present invention.

Hereinafter, preferred embodiments of the color conversion substrate and display according to the present invention will be specifically described, but the present invention is not limited to the following embodiments and may be variously modified according to an object and an application. Can be carried out.

The display 11 of FIG. 1 has an organic EL substrate 12 and a color conversion substrate 16. The organic EL substrate 12 has an organic EL element 13 provided on the transparent substrate 14 and a sealing layer 15 that covers the organic EL element 13. The color conversion substrate 16 has recesses on the substrate 110 partitioned by partition walls 19 arranged in a pattern corresponding to the organic EL element 13. In this recess, a recess in which the non-color conversion layer 17N and the blue color filter 18B were formed, a recess in which the green color conversion layer 17G and the yellow color filter 18Y were formed, a red color conversion layer 17R and a yellow color filter 18Y were formed. Consists of recesses.

The display 21 of FIG. 2 has an LED substrate 22 and a color conversion substrate 26. The LED substrate 22 has an LED 23 provided on the transparent substrate 24. The color conversion substrate 26 has recesses on the substrate 210, which are partitioned by partition walls 29 arranged in a pattern corresponding to the LED 23. In this recess, a recess in which the non-color conversion layer 27N and the blue color filter 28B were formed, a recess in which the green color conversion layer 27G and the yellow color filter 28Y were formed, a red color conversion layer 27R and a yellow color filter 28Y were formed. Consists of recesses. Further, the LED substrate 22 is preferably a mini LED substrate or a micro LED substrate in which fine LEDs are densely spread on individual pixels.

Here, the green color conversion layer is a layer that converts the light incident from the light source into green light having a peak wavelength of 500 nm or more and less than 580 nm. The red color conversion layer is a layer that converts light incident from a light source into red light having a peak wavelength of 580 nm or more and 750 nm or less.

<Area ratio of color conversion layer and non-color conversion layer>
The color conversion substrate in the present invention has a partition wall on the substrate, and has a green color conversion layer, a red color conversion layer, and a non-color conversion layer containing no phosphor in a region partitioned by the partition wall. In the substrate, when the area of the green color conversion layer is Sg, the area of the red color conversion layer is Sr, and the area of the non-color conversion layer is Sn, Sg, Sr, and Sn are the following formulas (A) and (A). B) Satisfies the relationship.

Formula (A) Sn <Sg
Equation (B) Sn <Sr

Here, the area in the present invention means that when the surfaces of the

color conversion layers

17N, 17G, and 17R are present parallel to the surface of the substrate 110 in FIG. 1, the area is observed from the surface perpendicular to the surface of the substrate 110. The calculated area. Further, when the surfaces of the

color conversion layers

17N, 17G, and 17R do not exist in parallel with the surface of the substrate 110, the area calculated by observing along the surfaces of the

color conversion layers

17N, 17G, and 17R. The relationship between the formulas (A) and (B) satisfies (i) the total area of the green color conversion layer existing on the color conversion substrate, the total area of the red color conversion layer, and the total area of the non-color conversion layer. (Ii) Regarding the total area of the green color conversion layer, the total area of the red color conversion layer, and the total area of the non-color conversion layer in one of the arbitrary 5 cm × 5 cm regions in the color conversion substrate. May be satisfied. The color conversion substrate according to the present invention is (ii) the total area of the green color conversion layer, the total area of the red color conversion layer, and the non-color conversion layer in one of the arbitrary 5 cm × 5 cm regions in the color conversion substrate. It is preferable to satisfy the relationship between the formula (A) and the formula (B) for the total area.

When Sn ≧ Sg and when Sn ≧ Sr, all the light sources corresponding to the red sub-pixel, the green sub-pixel, and the blue sub-pixel can be turned on and displayed in white, but the result is bluish white. There are challenges. Here, the sub-pixel is a pixel composed of only one primary color, which is obtained by further dividing a colored minute point (pixel) which is a constituent unit of a screen. Normally, sub-pixels of three adjacent colors of red, green, and blue (three primary colors of light) function as one pixel. However, when the relationship between the formula (A) and the formula (B) is satisfied, it is possible to achieve both preferable chromaticity and sufficient brightness without requiring a complicated circuit design and control system. In particular, the area of the red sub-pixel with low energy conversion efficiency is the largest.
Equation (C-1) Sn <Sg <Sr
It is preferable to satisfy the relationship of.
In addition, the area of the green sub-pixel is the largest for high brightness.
Equation (C-2) Sn <Sr <Sg
It is preferable to satisfy the relationship of.

Further, it is preferable that Sg, Sr, and Sn satisfy at least one of the following relations of the formula (D) and the formula (E).
Equation (D) 1.0 <Sg / Sn ≦ 5.0
Equation (E) 1.0 <Sr / Sn ≦ 5.0
By satisfying the relationship of the formula (D), the brightness of green having high luminosity factor can be increased, and the brightness of the display can be further improved, which is preferable.

Further, by satisfying the relationship of the formula (E), it is possible to improve the brightness of red, which has a particularly low energy conversion efficiency, and it is possible to further improve the brightness of the display, which is preferable.

Sg / Sn is preferably greater than 1.0, more preferably 1.8 or more, and even more preferably 2.4 or more. Further, it is preferably 5.0 or less, and more preferably 4.0 or less.

Sr / Sn is preferably greater than 1.0, more preferably 1.9 or more, and even more preferably 3.0 or more. Further, it is preferably 5.0 or less, and more preferably 4.2 or less.

The planar shape of the partition wall can be striped. Here, the planar shape means a shape when the color conversion substrate is viewed from directly above. Looking at the color conversion substrate from directly above means observing the color conversion substrate in the direction perpendicular to the surface of the substrate 110 in FIG. FIG. 3 shows an example in which the planar shape of the partition wall is striped. The striped shape means that the partition walls are arranged substantially parallel to each other. Further, the line width of a part of the partition wall may be different. Since the partition wall has a striped shape, it is possible to reduce color mixing in the process of forming the color conversion layer, and it is possible to manufacture a display with a high yield. It is preferable that the red color conversion layer R, the green color conversion layer G, and the non-color conversion layer B are formed in each of the striped regions. The red color conversion layer R, the green color conversion layer G, and the non-color conversion layer B may have color conversion layers of different colors formed in adjacent regions as shown in FIG. 3, or color conversion layers of the same color. May be formed adjacent to each other.

The planar shape of the partition wall can also be a grid pattern. Here, the grid shape means a shape obtained by intersecting a plurality of vertical partition walls and horizontal partition walls. FIG. 4 shows an example in which the planar shape of the partition wall is a grid pattern. The angle at which the vertical partition wall and the horizontal partition wall intersect is not particularly limited, and the angle may be different for each lattice. The angles are preferably approximately orthogonal. By forming the planar shape of the partition wall into a lattice, it is possible to improve the reflectance of the color conversion substrate, and it is possible to obtain a display having better brightness.

Further, the planar shape of the partition wall can be any shape such as the polygon of FIG. 5 and the triangle of FIG. In addition, a plurality of arbitrary shapes such as stripes, grids, polygons, and triangles may be used in combination.

<Light source>
The light source used in the display according to the present invention is preferably a light source composed of a plurality of light sources and capable of partial drive. By using a partially driveable light source, the display can be turned ON / OFF without using a liquid crystal panel, and a display having excellent contrast and response speed can be obtained. Any type of light source can be used as long as it can emit light that can excite the phosphor in the color conversion layer. For example, any excitation light such as a hot cathode tube, a cold cathode tube, a fluorescent light source such as an inorganic electroluminescence (EL), an organic EL element light source, an LED light source, and an incandescent light source can be used in principle. In FIG. 1, the organic EL element 13 corresponds to the light source, and in FIG. 2, the LED 23 corresponds to the light source. The excitation light may have one type of emission peak or may have two or more types of emission peaks, but in order to increase the color purity, one having one type of emission peak is preferable. It is also possible to use a plurality of light sources having different types of emission peaks in any combination.

In display and lighting applications, it is preferable that the light source emits blue light or blue-green light in that the color purity of blue light can be increased. As blue light or blue-green light, it is preferable to have a maximum wavelength in the wavelength range of 430 to 500 nm, and the emission spectrum may be a single peak or a double peak. Further, those having a maximum wavelength in the wavelength range of 430 to 500 nm have a first peak in the wavelength range of 430 nm to 500 nm and a second peak in the wavelength range of 500 nm to 700 nm, such as YAG-based LEDs. Although some of them have, those having no maximum wavelength of 500 nm to 700 nm are preferable from the viewpoint of improving the color purity of blue. Further, having a peak in the wavelength range of 430 nm to 500 nm is a more preferable excitation light. The excitation light in the wavelength range of 430 nm to 500 nm has a relatively small excitation energy and can prevent decomposition of the organic light emitting material. Therefore, the light source used for the light source unit is preferably a light source having maximum light emission in the wavelength range of 430 nm or more and 500 nm or less. Further, this light source preferably has maximum light emission in a wavelength range of 440 nm or more and 470 nm or less.

The light source used in the display according to the present invention is preferably a plurality of partially driveable blue light sources.

The light source used in the display according to the present invention is preferably a light emitting diode. When the light source is a light emitting diode, a plurality of light sources can be arranged in high definition, so that a high resolution display is possible. Further, since the light emitting diode has a high light emitting intensity, a display having high brightness is possible.

Further, it is preferable that the light emitting diode has a gallium nitride based compound semiconductor in that the color purity of blue light can be increased. Since the light emitting diode is a gallium nitride compound semiconductor, the emission of excitation light can be sharpened and the color purity is improved.

The light source is preferably an organic electroluminescent element in which an organic layer exists between the anode and the cathode and emits light by electric energy. When the light source is an organic electroluminescent element that has an organic layer between the anode and the cathode and emits light by electric energy, a plurality of light sources can be arranged with high definition, so that a high-resolution display is possible. Further, since the organic electroluminescent element can be made thinner, it can contribute to making the display itself thinner.

More specifically, the organic electroluminescent element has an anode and a cathode, and an organic layer interposed between the anode and the cathode, and the organic layer has at least a light emitting layer and an electron transporting layer, and the organic layer is provided. It is preferable that the layer, particularly the light emitting layer, is a light source that emits light by electroluminescence.

The organic layer is composed of only a light emitting layer / an electron transport layer, 1) a hole transport layer / a light emitting layer / an electron transport layer, and 2) a hole transport layer / a light emitting layer / an electron transport layer / an electron injection layer. 3) A laminated structure such as a hole injection layer / a hole transport layer / a light emitting layer / an electron transport layer / an electron injection layer can be mentioned. Further, each of the above layers may be either a single layer or a plurality of layers. Further, it may be a laminated type having a plurality of phosphorescent light emitting layers or fluorescent light emitting layers, or may be a light emitting element in which a fluorescent light emitting layer and a phosphorescent light emitting layer are combined. Further, light emitting layers having different emission colors can be laminated.

Further, the above element configuration may be a tandem type in which a plurality of elements are laminated via an intermediate layer. Above all, at least one layer is preferably a phosphorescent layer. The intermediate layer is also generally referred to as an intermediate electrode, an intermediate conductive layer, a charge generation layer, an electron extraction layer, a connection layer, or an intermediate insulating layer, and a known material structure can be used. Specific examples of the tandem type include, for example, 4) hole transport layer / light emitting layer / electron transport layer / charge generation layer / hole transport layer / light emitting layer / electron transport layer, 5) hole injection layer / hole transport layer / A charge generation layer is provided as an intermediate layer between the anode and the cathode, such as a light emitting layer / electron transport layer / electron injection layer / charge generation layer / hole injection layer / hole transport layer / light emitting layer / electron transport layer / electron injection layer. A laminated structure including is mentioned. Specifically, a pyridine derivative and a phenanthroline derivative are preferably used as the material constituting the intermediate layer.

Further, it is preferable that it is a top emission type organic electroluminescent device. In the case of a top-emission type organic electroluminescent element, for example, a method in which the anode has a laminated structure of a reflective electrode layer and a transparent electrode layer and the film thickness of the transparent electrode layer on the reflective electrode layer is changed can be mentioned. A microcavity structure can be introduced into an organic electroluminescent device by appropriately laminating an organic layer on the anode and then using, for example, thin-film translucent silver or the like as a translucent electrode for the cathode. When the microcavity structure is introduced into the organic electroluminescent device in this way, the spectrum of the light emitted from the organic layer and emitted through the cathode becomes steeper than when the organic electroluminescent device does not have the microcavity structure. In addition, the injection strength to the front is greatly increased. When this is used for a display, it contributes to the improvement of color gamut and the improvement of brightness.

<Light emitting layer>
The light emitting layer may be either a single layer or a plurality of layers, and each is formed of a light emitting material (host material, dopant material). The material constituting the light emitting layer may be a mixture of the host material and the dopant material, or may be the host material alone. Further, the host material and the dopant material may be either one type or a plurality of combinations. The dopant material may be contained entirely or partially in the host material. The dopant material may be laminated or dispersed. The light emitting layer in which the host material and the dopant material are mixed can be formed by a co-deposition method of the host material and the dopant material or a method of premixing the host material and the dopant material and then vapor deposition.

Specifically, the luminescent material is a fused ring derivative such as anthracene or pyrene, which has been known as a luminescent material for a long time, a metal chelating oxynoid compound such as tris (8-quinolinolato) aluminum, a bisstyryl anthracene derivative or di Bistylyl derivatives such as styrylbenzene derivatives, dibenzofuran derivatives, carbazole derivatives, indolocarbazole derivatives and the like can be used, but are not particularly limited.

As the host material, an anthracene derivative or naphthacene derivative is preferable.

In particular, it is preferable that the host material contains an anthracene-based host material. When the host material contains an anthracene-based host material, high color purity and high-efficiency light emission are possible, which can contribute to low power consumption of the display.

As the dopant material, a boron complex-based dopant material, a pyrene-based dopant material, a chrysene-based dopant material, a benzofluorentene-based dopant material, and an amine-based dopant material are preferable. Boron complex-based dopant materials, pyrene-based dopant materials, chrysene-based dopant materials, benzofluorane-based dopant materials, and amine-based dopant materials exhibit extremely sharp light emission, and thus improve color purity. Further, it is preferable that the dopant material is an amine-based dopant material because the brightness is improved. On the other hand, it is preferable that the dopant material is a boron complex-based dopant material because the color gamut is improved. Among the boron complex-based dopant materials, the quinoline boron complex-based dopant material is preferable because it exhibits particularly sharp light emission.

Further, the light emitting layer may contain a phosphorescent material. The phosphorescent material is a material that emits phosphorescent light even at room temperature. When a phosphorescent material is used as the dopant material, an organometallic complex having iridium or platinum is more preferable from the viewpoint of having a high phosphorescent yield even at room temperature. Hosts used in combination with phosphorescent dopants include indol derivatives, carbazole derivatives, indolocarbazole derivatives, pyridines, pyrimidines, nitrogen-containing aromatic compound derivatives with a triazine skeleton, polyarylbenzene derivatives, spirofluorene derivatives, Aromatic hydrocarbon compound derivatives such as tolucene derivatives and triphenylene derivatives, compounds containing chalcogen elements such as dibenzofuran derivatives and dibenzothiophene derivatives, and organic metal complexes such as beryllium quinolinol complexes are preferably used. The triplet energy is larger than that of a generally used dopant, and the electrons and holes are not limited to these as long as they are smoothly injected and transported from the respective transport layers. Further, two or more kinds of triplet light emitting dopants may be contained, or two or more kinds of host materials may be contained. Further, one or more triplet emission dopants and one or more fluorescence emission dopants may be contained.

Further, it is preferable that the light emitting layer contains a heat-activated delayed fluorescent material. Thermally activated delayed fluorescent materials, also commonly referred to as TADF materials, reduce the energy gap between the singlet excited state energy level and the triplet excited state energy level to reduce the triplet excited state to the singlet. It is a material that promotes the inverse intersystem crossing to the excited state and improves the probability of singlet exciter generation. When the light emitting layer contains a heat-activated delayed fluorescent material, more efficient light emission becomes possible, which contributes to lower power consumption of the display. The heat-activated delayed fluorescence material may be a material that exhibits heat-activated delayed fluorescence with a single material, or may be a material that exhibits heat-activated delayed fluorescence with a plurality of materials. The heat-activated delayed fluorescent material used may be a single material or a plurality of materials, and known materials can be used. Specific examples thereof include benzonitrile derivatives, triazine derivatives, disulfoxide derivatives, carbazole derivatives, indolocarbazole derivatives, dihydrophenazine derivatives, thiazole derivatives, and oxadiazole derivatives.

<Recess>
The recess used in the present invention refers to a region partitioned by arranging partition walls in a pattern so as to correspond to a plurality of light sources. In FIG. 1, the region partitioned by the partition walls 19 arranged in a pattern on the substrate 110 corresponds to the recess, and in FIG. 2, the region partitioned by the partition walls 29 arranged in a pattern on the substrate 210 corresponds to the recess. Corresponds to. The material that can be used for the partition wall may be either photosensitive or non-photosensitive, and specifically, an epoxy resin, an acrylic resin, a siloxane polymer resin, a polyimide resin, or the like is preferably used.

For the partition wall, a predetermined thin film is formed by a wet coating method such as spin coating, dip coating, roll coating, gravure coating, dispenser, etc., and further resist coating, prebaking, exposure, development, post-baking, etching, resist removal, etc. The pattern may be produced by utilizing the including photolithography method. Further, when a partition wall is formed using a solid material such as LiF or MgF ₂ , a film is formed by a dry process such as vacuum deposition or sputtering, and then a photolithography method as described above or a dry process such as etching is performed. The process may form a predetermined pattern.

The film thickness of the partition wall is preferably larger than the film thickness of the color conversion layer, and is preferably in the range of 1 to 100 μm. Further, the pattern of the partition wall may be sufficient as long as it is sufficient to prevent color mixing with the color conversion layer formed in the adjacent recesses, and is preferably 10 to 50 μm, more preferably 15 to 30 μm. .. The shape of the concave portion is not particularly limited, and various shapes such as a striped shape, a grid shape, a triangular shape, a diamond shape, a hexagonal shape, and the like can be adopted. From the viewpoint of easy production and prevention of crosstalk, which will be described later, the shape of the recesses is preferably a grid pattern. Crosstalk refers to a phenomenon in which the color of a lit pixel leaks to adjacent pixels, and examples thereof include displaying green light in a pixel for displaying red.

<Color conversion unit>
The color conversion unit is a unit provided with a green color conversion layer, which will be described later, or a recess forming a red color conversion layer. It is preferable that the color conversion unit has a color conversion layer formed in a plurality of recesses. By forming the color conversion layer in the plurality of recesses, it is possible to prevent color mixing with the light emission of the adjacent color conversion layer and enable a high-resolution display.

Further, it is preferable that the color conversion layer formed in the recess is composed of two or more types of color conversion layers that emit emitted light in different wavelength regions. Since the color conversion layer is composed of at least two types of color conversion layers, it is possible to control the emission of different colors, and it is possible to make the display multicolored.

The green color conversion unit forming the green color conversion layer preferably has a single emission peak in a region having a wavelength of 500 nm or more and less than 580 nm. Here, having a single emission peak means that there is no peak having an intensity of 5% or more of the peak having a maximum value in a region having a wavelength of 500 nm or more and less than 580 nm.

Further, the red color conversion unit forming the red color conversion layer preferably has a single emission peak in a region having a wavelength of 580 nm or more and 750 nm or less. Having a single emission peak means that there is no peak having an intensity of 5% or more of the peak having a maximum value in a region having a wavelength of 580 nm or more and 750 nm or less.

<Non-color conversion unit>
The non-color conversion unit is a portion provided with a recess forming a non-color conversion layer, which will be described later. By providing the recess having the non-color conversion layer, the blue light of the light source can be transmitted, and the blue light can be efficiently used, which contributes to high efficiency of the display.

<Color conversion layer>
The color conversion layer included in the present invention is a layer having a function of converting at least a part of a wavelength region of incident light and emitting emitted light in a wavelength region different from that of the incident light. The color conversion layer contains at least a light emitting material and a matrix resin. The color conversion layer may further contain inorganic particles and other additives.

From the viewpoint of increasing the color purity, the green color conversion layer preferably has a single emission peak in a region having a wavelength of 500 nm or more and less than 580 nm. Here, having a single emission peak means that there is no peak having an intensity of 5% or more of the peak having a maximum value in a region having a wavelength of 500 nm or more and less than 580 nm.

Further, from the viewpoint of increasing the color purity, the red color conversion layer preferably has a single emission peak in the region of wavelength 580 nm or more and 750 nm or less. Having a single emission peak means that there is no peak having an intensity of 5% or more of the peak having a maximum value in a region having a wavelength of 580 nm or more and 750 nm or less.

<Non-color conversion layer>
The non-color conversion layer included in the present invention is a layer that does not absorb incident light or emits light in a wavelength region different from that of incident light even if it partially absorbs it. The non-color conversion layer may be an air layer or a resin layer. In the case of the resin layer, inorganic particles and other additives may be further contained.

<Luminescent material>
Known light emitting materials can be used, but since quantum dots and organic light emitting materials can efficiently absorb the light emitted from the light source, high efficiency can be achieved when used in the color conversion layer. .. Inorganic phosphors such as β-SiAlON phosphors and KSF phosphors can also be used, but quantum dots and organic light emitting materials having high absorption efficiency per unit weight at the excitation wavelength are preferably used as the light emitting material. It is more preferable to use an organic light emitting material as the light emitting material.

Examples of the organic light emitting material include compounds having a fused aryl ring such as naphthalene, anthracene, phenanthrene, pyrene, chrysene, naphthalene, triphenylene, perylene, fluoranthene, fluorene, and indene, and derivatives thereof;
Furan, pyrrol, thiophene, silol, 9-silafluorene, 9,9'-spirobisilafluorene, benzothiophene, benzofuran, indole, dibenzothiophene, dibenzofuran, imidazopyridine, phenanthroline, pyridine, pyrazine, diazanaphthalene, quinoxaline, pyrolopyridine Compounds having a heteroaryl ring such as and derivatives thereof;
Borane derivative;
1,4-Distyrylbenzene, 4,4'-bis (2- (4-diphenylaminophenyl) ethenyl) biphenyl, 4,4'-bis (N- (stilbene-4-yl) -N-phenylamino) Stilbene derivatives such as stilbene;
Aromatic acetylene derivatives, tetraphenylbutadiene derivatives, aldazine derivatives, pyromethene derivatives, diketopyrrole [3,4-c] pyrrole derivatives;
Coumarin derivatives such as coumarin 6, coumarin 7, coumarin 153;
Azole derivatives such as imidazole, thiazole, thiadiazole, carbazole, oxazole, oxadiazole, triazole and their metal complexes;
Cyanine compounds such as indocyanine green;
Xanthene compounds such as fluorescein, eosin, and rhodamine and thioxanthene compounds;
Polyphenylene compounds, naphthalimide derivatives, phthalocyanine derivatives and their metal complexes, porphyrin derivatives and their metal complexes;
Oxazine compounds such as Nile Red and Nile Blue;
Helicene compounds;
Aromatic amine derivatives such as N, N'-diphenyl-N, N'-di (3-methylphenyl) -4,4'-diphenyl-1,1'-diamine; and iridium (Ir), ruthenium (Ru) , Rhodium (Rh), palladium (Pd), platinum (Pt), osmium (Os), and ruthenium (Re) and other organic metal complex compounds;
Etc. are mentioned as suitable ones, but are not particularly limited thereto.

The organic light emitting material may be a fluorescent light emitting material or a phosphorescent light emitting material, but in order to achieve high color purity, the fluorescent light emitting material is preferable.

Among these, compounds having a condensed aryl ring and derivatives thereof can be preferably used because of their high thermal stability and photostability.

Further, from the viewpoint of solubility and diversity of molecular structure, a compound having a coordination bond is preferable. A boron-containing compound such as a boron fluoride complex is also preferable because it has a small half-value width and can emit light with high efficiency.

Among them, the pyrromethene derivative can be preferably used in that it gives a high fluorescence quantum yield and has good durability. More preferably, it is a compound represented by the general formula (1).

X is CR ⁷ or N. R ¹ to R ⁹ may be the same or different, respectively, and hydrogen, alkyl group, cycloalkyl group, heterocyclic group, alkenyl group, cycloalkenyl group, alkynyl group, hydroxyl group, thiol group, alkoxy group, alkylthio group and aryl. Ether group, arylthioether group, aryl group, heteroaryl group, halogen, cyano group, aldehyde group, carbonyl group, carboxyl group, ester group, carbamoyl group, amino group, nitro group, silyl group, siloxanyl group, boryl group, sulfo It is selected from a fused ring and an aliphatic ring formed between a group, a phosphine oxide group, and an adjacent substituent.

In all the above groups, hydrogen may be deuterium. This also applies to the compounds described below or their partial structures. Further, in the following description, for example, a substituted or unsubstituted aryl group having 6 to 40 carbon atoms has all carbon atoms of 6 to 40 including the carbon number contained in the substituent substituted with the aryl group. It is an aryl group. The same applies to other substituents that specify the number of carbon atoms.

Further, in all the above groups, the substituents in the case of substitution include an alkyl group, a cycloalkyl group, a heterocyclic group, an alkenyl group, a cycloalkenyl group, an alkynyl group, a hydroxyl group, a thiol group, an alkoxy group and an alkylthio group. , Aryl ether group, aryl thioether group, aryl group, heteroaryl group, halogen, cyano group, aldehyde group, carbonyl group, carboxyl group, ester group, carbamoyl group, amino group, nitro group, silyl group, siloxanyl group, boryl group. , Sulf group and phosphine oxide group are preferable, and specific substituents which are preferable in the description of each substituent are preferable. Further, these substituents may be further substituted with the above-mentioned substituents.

"Unsubstituted" in the case of "substituted or unsubstituted" means that a hydrogen atom or a deuterium atom has been substituted. The same applies to the case of "substituted or unsubstituted" in the compound described below or its partial structure.

Of all the above groups, the alkyl group is a saturated aliphatic hydrocarbon such as a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, a sec-butyl group and a tert-butyl group. Shows a group, which may or may not have a substituent. The additional substituent when substituted is not particularly limited, and examples thereof include an alkyl group, a halogen, an aryl group, and a heteroaryl group, and this point is also common to the following description. The number of carbon atoms of the alkyl group is not particularly limited, but is preferably in the range of 1 or more and 20 or less, more preferably 1 or more and 8 or less, from the viewpoint of availability and cost.

The cycloalkyl group means, for example, a saturated alicyclic hydrocarbon group such as a cyclopropyl group, a cyclohexyl group, a norbornyl group, and an adamantyl group, which may or may not have a substituent. .. The number of carbon atoms in the alkyl group moiety is not particularly limited, but is preferably in the range of 3 or more and 20 or less.

The heterocyclic group refers to an aliphatic ring having an atom other than carbon such as a pyran ring, a piperidine ring, and a cyclic amide in the ring, which may or may not have a substituent. Good. The number of carbon atoms of the heterocyclic group is not particularly limited, but is preferably in the range of 2 or more and 20 or less.

The alkenyl group refers to an unsaturated aliphatic hydrocarbon group containing a double bond such as a vinyl group, an allyl group, a butadienyl group, etc., which may or may not have a substituent. .. The carbon number of the alkenyl group is not particularly limited, but is preferably in the range of 2 or more and 20 or less.

The cycloalkenyl group refers to an unsaturated alicyclic hydrocarbon group containing a double bond such as a cyclopentenyl group, a cyclopentadienyl group, a cyclohexenyl group, etc., even if it has a substituent. You do not have to have it.

The alkynyl group refers to an unsaturated aliphatic hydrocarbon group containing a triple bond such as an ethynyl group, which may or may not have a substituent. The carbon number of the alkynyl group is not particularly limited, but is preferably in the range of 2 or more and 20 or less.

The alkoxy group refers to a functional group to which an aliphatic hydrocarbon group is bonded via an ether bond such as a methoxy group, an ethoxy group, or a propoxy group, and the aliphatic hydrocarbon group has a substituent. You do not have to have. The number of carbon atoms of the alkoxy group is not particularly limited, but is preferably in the range of 1 or more and 20 or less.

The alkylthio group is one in which the oxygen atom of the ether bond of the alkoxy group is replaced with a sulfur atom. The hydrocarbon group of the alkylthio group may or may not have a substituent. The number of carbon atoms of the alkylthio group is not particularly limited, but is preferably in the range of 1 or more and 20 or less.

The aryl ether group refers to a functional group to which an aromatic hydrocarbon group is bonded via an ether bond, such as a phenoxy group, and the aromatic hydrocarbon group may or may not have a substituent. May be good. The number of carbon atoms of the aryl ether group is not particularly limited, but is preferably in the range of 6 or more and 40 or less.

The arylthio ether group is one in which the oxygen atom of the ether bond of the aryl ether group is replaced with a sulfur atom. The aromatic hydrocarbon group in the arylthioether group may or may not have a substituent. The number of carbon atoms of the arylthioether group is not particularly limited, but is preferably in the range of 6 or more and 40 or less.

The aryl group is, for example, a phenyl group, a biphenyl group, a terphenyl group, a naphthyl group, a fluorenyl group, a benzofluorenyl group, a dibenzofluorenyl group, a phenanthryl group, an anthrasenyl group, a benzophenanthryl group, a benzoanthrase. It shows an aromatic hydrocarbon group such as an Nyl group, a chrysenyl group, a pyrenyl group, a fluoranthenyl group, a triphenylenyl group, a benzofluoranthenyl group, a dibenzoanthrasenyl group, a perylenel group and a helisenyl group. Of these, a phenyl group, a biphenyl group, a terphenyl group, a naphthyl group, a fluorenyl group, a phenanthryl group, an anthracenyl group, a pyrenyl group, a fluoranthenyl group and a triphenylenyl group are preferable. The aryl group may or may not have a substituent. The number of carbon atoms of the aryl group is not particularly limited, but is preferably in the range of 6 or more and 40 or less, and more preferably 6 or more and 30 or less.

When R ¹ to R ⁹ are substituted or unsubstituted aryl groups, the aryl group is preferably a phenyl group, a biphenyl group, a terphenyl group, a naphthyl group, a fluorenyl group, a phenanthryl group, an anthrasenyl group, preferably a phenyl group or a biphenyl group. Groups, turphenyl groups and naphthyl groups are more preferred. More preferably, it is a phenyl group, a biphenyl group, a terphenyl group, and a phenyl group is particularly preferable.

When each substituent is further substituted with an aryl group, the aryl group is preferably a phenyl group, a biphenyl group, a terphenyl group, a naphthyl group, a fluorenyl group, a phenanthryl group or an anthrasenyl group, preferably a phenyl group, a biphenyl group or a ter. A phenyl group and a naphthyl group are more preferable. Particularly preferred is a phenyl group.

The heteroaryl group is, for example, a pyridyl group, a furanyl group, a thienyl group, a quinolinyl group, an isoquinolinyl group, a pyrazinyl group, a pyrimidyl group, a pyridadinyl group, a triazine group, a naphthyldinyl group, a synnolinyl group, a phthalazinyl group, a quinoxalinyl group, a quinazolinyl group, Benzofuranyl group, benzothienyl group, indolyl group, dibenzofuranyl group, dibenzothienyl group, carbazolyl group, benzocarbazolyl group, carbolinyl group, indolocarbazolyl group, benzofluorocarbazolyl group, benzothienocarbazolyl Non-carbon atoms such as groups, dihydroindenocarbazolyl groups, benzoquinolinyl groups, acridinyl groups, dibenzoacrydinyl groups, benzoimidazolyl groups, imidazoly pyridyl groups, benzoxazolyl groups, benzothiazolyl groups, phenanthrolinyl groups, etc. Indicates a cyclic aromatic group having one or more rings in the ring. However, the naphthyldinyl group is any of 1,5-naphthylidine group, 1,6-naphthylidine group, 1,7-naphthylidine group, 1,8-naphthylidine group, 2,6-naphthylidine group, and 2,7-naphthylidine group. Indicates. The heteroaryl group may or may not have a substituent. The number of carbon atoms of the heteroaryl group is not particularly limited, but is preferably in the range of 2 or more and 40 or less, and more preferably 2 or more and 30 or less.

When R ¹ to R ⁹ are substituted or unsubstituted heteroaryl groups, the heteroaryl groups include pyridyl group, furanyl group, thienyl group, quinolinyl group, pyrimidyl group, triazinyl group, benzofuranyl group, benzothienyl group and indrill. Group, dibenzofuranyl group, dibenzothienyl group, carbazolyl group, benzoimidazolyl group, imidazole pyridyl group, benzoxazolyl group, benzothiazolyl group, phenanthrolinyl group are preferable, and pyridyl group, furanyl group, thienyl group and quinolinyl group are preferable. More preferred. Particularly preferred is a pyridyl group.

When each substituent is further substituted with a heteroaryl group, the heteroaryl group includes pyridyl group, furanyl group, thienyl group, quinolinyl group, pyrimidyl group, triazinyl group, benzofuranyl group, benzothienyl group, indolyl group, dibenzo. A furanyl group, a dibenzothienyl group, a carbazolyl group, a benzoimidazolyl group, an imidazole pyridyl group, a benzoxazolyl group, a benzothiazolyl group and a phenanthrolinyl group are preferable, and a pyridyl group, a furanyl group, a thienyl group and a quinolinyl group are more preferable. Particularly preferred is a pyridyl group.

Halogen refers to an atom selected from fluorine, chlorine, bromine and iodine. Further, the carbonyl group, the carboxyl group, the ester group and the carbamoyl group may or may not have a substituent. Here, examples of the substituent include an alkyl group, a cycloalkyl group, an aryl group, a heteroaryl group and the like, and these substituents may be further substituted.

The amino group is a substituted or unsubstituted amino group. Examples of the substituent in the case of substitution include an aryl group, a heteroaryl group, a linear alkyl group, a branched alkyl group and the like. As the aryl group and heteroaryl group, a phenyl group, a naphthyl group, a pyridyl group and a quinolinyl group are preferable. These substituents may be further substituted. The number of carbon atoms is not particularly limited, but is preferably 2 or more and 50 or less, more preferably 6 or more and 40 or less, and particularly preferably 6 or more and 30 or less.

The silyl group is, for example, an alkylsilyl group such as a trimethylsilyl group, a triethylsilyl group, a tert-butyldimethylsilyl group, a propyldimethylsilyl group, a vinyldimethylsilyl group, a phenyldimethylsilyl group, a tert-butyldiphenylsilyl group, or a tri. Indicates an arylsilyl group such as a phenylsilyl group and a trinaphthylsilyl group. Substituents on silicon may be further substituted. The number of carbon atoms of the silyl group is not particularly limited, but is preferably in the range of 1 or more and 30 or less.

The siloxanyl group refers to, for example, a silicon compound group via an ether bond such as a trimethylsiloxanyl group. Substituents on silicon may be further substituted. The boryl group is a substituted or unsubstituted boryl group. Examples of the substituent in the case of substitution include an aryl group, a heteroaryl group, a linear alkyl group, a branched alkyl group, an aryl ether group, an alkoxy group, a hydroxyl group and the like. Of these, aryl groups and aryl ether groups are preferable. The sulfo group is a substituted or unsubstituted sulfo group. Examples of the substituent in the case of substitution include an aryl group, a heteroaryl group, a linear alkyl group, a branched alkyl group, an aryl ether group, an alkoxy group and the like. Of these, a linear alkyl group and an aryl group are preferable. The phosphine oxide group is a group represented by −P (= O) R ¹⁰ R ¹¹ . R ¹⁰ R ¹¹ is selected from the same group as R ¹ to R ⁹ .

The condensed ring and the aliphatic ring formed between the adjacent substituents are conjugated or unconjugated by any adjacent bisubstituted groups (for example, R ¹ and R ² of the general formula (1)) bonded to each other. It means to form a circular skeleton of. The constituent elements of such a fused ring and the aliphatic ring may contain elements selected from nitrogen, oxygen, sulfur, phosphorus and silicon in addition to carbon. Moreover, these condensed ring and aliphatic ring may be condensed with yet another ring.

Since the compound represented by the general formula (1) exhibits a high emission quantum yield and a small half-value width of the emission spectrum, both efficient color conversion and high color purity can be achieved. Further, the compound represented by the general formula (1) has various properties such as luminous efficiency, color purity, thermal stability, photostability and dispersibility by introducing an appropriate substituent at an appropriate position. And physical properties can be adjusted. For example, at least one of R ¹ , R ³ , R ⁴ and R ⁶ is a substituted or unsubstituted alkyl group or a substituted or unsubstituted alkyl group as compared with the case where R ¹ , R ³ , R ⁴ and R ⁶ are all hydrogen. Aryl groups, substituted or unsubstituted heteroaryl groups show better thermal and photostability.

When at least one of R ¹ , R ³ , R ⁴ and R ⁶ is a substituted or unsubstituted alkyl group, the alkyl group includes a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, and the like. Alkyl groups having 1 to 6 carbon atoms such as sec-butyl group, tert-butyl group, pentyl group and hexyl group are preferable. Further, as this alkyl group, a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, a sec-butyl group and a tert-butyl group are preferable from the viewpoint of excellent thermal stability. Further, from the viewpoint of preventing concentration quenching and improving the emission quantum yield, the tert-butyl group having a high sterically bulk is more preferable as the alkyl group. A methyl group is also preferably used as the alkyl group from the viewpoint of ease of synthesis and availability of raw materials.

When at least one of R ¹ , R ³ , R ⁴ and R ⁶ is a substituted or unsubstituted aryl group, the aryl group is preferably a phenyl group, a biphenyl group, a terphenyl group, or a naphthyl group, and more preferably. It is a phenyl group and a biphenyl group. Particularly preferred is a phenyl group.

When at least one of R ¹ , R ³ , R ⁴ and R ⁶ is a substituted or unsubstituted heteroaryl group, the heteroaryl group is preferably a pyridyl group, a quinolinyl group or a thienyl group, and more preferably a pyridyl group. , Kinolinyl group. Particularly preferred is a pyridyl group.

R ¹ , R ³ , R ⁴ and R ⁶ may all be the same or different, and a substituted or unsubstituted alkyl group is preferable because it has good solubility in a binder resin or a solvent. In this case, the alkyl group is preferably a methyl group from the viewpoint of easiness of synthesis and availability of raw materials.

R ¹ , R ³ , R ⁴ and R ⁶ may all be the same or different, respectively, with better thermal stability and better thermal stability when they are substituted or unsubstituted aryl groups or substituted or unsubstituted heteroaryl groups. It is preferable because it shows photostability. In this case, R ¹ , R ³ , R ⁴ and R ⁶ may all be the same or different, and are more preferably substituted or unsubstituted aryl groups.

Although there are substituents that improve multiple properties, the substituents that show sufficient performance in all are limited. In particular, it is difficult to achieve both high luminous efficiency and high color purity. Therefore, by introducing a plurality of types of substituents into the compound represented by the general formula (1), it is possible to obtain a compound having a good balance in light emission characteristics, color purity and the like.

In particular, R ¹ , R ³ , R ⁴ and R ⁶ may all be the same or different, and in the case of substituted or unsubstituted aryl groups, for example, R ¹ ≠ R ⁴ , R ³ ≠ R ⁶ , R It is preferable to introduce a plurality of types of substituents such as ¹ ≠ R ³ or R ⁴ ≠ R ⁶ . Here, "≠" indicates that the bases have different structures. For example, R ¹ ≠ R ⁴ indicates that R ¹ and R ⁴ are groups of different structures. By introducing a plurality of types of substituents as described above, an aryl group that affects color purity and an aryl group that affects luminous efficiency can be introduced at the same time, so that fine adjustment is possible.

Above all, it is preferable that R ¹ ≠ R ³ or R ⁴ ≠ R ⁶ from the viewpoint of improving the luminous efficiency and the color purity in a well-balanced manner. In this case, for the compound represented by the general formula (1), one or more aryl groups that affect the color purity are introduced into the pyrrole rings on both sides, and the aryl that affects the luminous efficiency at other positions. Since the group can be introduced, both of these properties can be improved to the maximum. Further, when R ¹ ≠ R ³ or R ⁴ ≠ R ⁶ , it is more preferable that R ¹ = R ⁴ and R ³ = R ⁶ from the viewpoint of improving both heat resistance and color purity.

As the aryl group that mainly affects the color purity, an aryl group substituted with an electron donating group is preferable. An electron-donating group is an atomic group that donates electrons to an atomic group substituted by an inductive effect or a resonance effect in organic electron theory. Examples of the electron donating group include those having a negative value as the substituent constant (σp (para)) of Hammett's law. The Hammett equation substituent constant (σp (para)) can be quoted from the 5th edition of the Basics of Chemistry Handbook (page II-380).

Specific examples of the electron donating group include an alkyl group (methyl group σp: −0.17), an alkoxy group (methoxy group σp: −0.27), and an amino group (−NH ₂ σp: −”. 0.66) and the like can be mentioned. In particular, an alkyl group having 1 to 8 carbon atoms or an alkoxy group having 1 to 8 carbon atoms is preferable, and a methyl group, an ethyl group, a tert-butyl group and a methoxy group are more preferable. From the viewpoint of dispersibility, a tert-butyl group and a methoxy group are particularly preferable, and when these are used as the above-mentioned electron-donating groups, in the compound represented by the general formula (1), quenching due to aggregation of molecules is prevented. be able to. The substitution position of the substituent is not particularly limited, but since it is necessary to suppress the twist of the bond in order to enhance the photostability of the compound represented by the general formula (1), the meta is relative to the bond position with the pyrromethene skeleton. It is preferable to combine with the position or para position. On the other hand, as the aryl group that mainly affects the luminous efficiency, an aryl group having a bulky substituent such as a tert-butyl group, an adamantyl group, or a methoxy group is preferable.

If R ¹ , R ³ , R ⁴ and R ⁶ are the same or different, respectively, and are substituted or unsubstituted aryl groups, then R ¹ , R ³ , R ⁴ and R ⁶ are the same or different, respectively. It may be a substituted or unsubstituted phenyl group, and is preferable. At this time, it is more preferable that R ¹ , R ³ , R ⁴ and R ⁶ are selected from the following Ar-1 to Ar-6, respectively. In this case, the combination of R ¹ , R ³ , R ⁴ and R ⁶ is not particularly limited.

R ² and R ⁵ are preferably any of hydrogen, alkyl group, carbonyl group, ester group and aryl group. Of these, hydrogen or an alkyl group is preferable from the viewpoint of thermal stability, and hydrogen is more preferable from the viewpoint of easily obtaining a narrow full width at half maximum in the emission spectrum.

R ⁸ and R ⁹ are alkyl groups, aryl groups, heteroaryl groups, alkoxy groups, aryl ether groups, fluorines, fluorine-containing alkyl groups, fluorine-containing heteroaryl groups or fluorine-containing aryl groups, fluorine-containing alkoxy groups, and fluorine-containing aryls. An ether group and a cyano group are preferable, and a fluorine, a cyano group, or a fluorine-containing aryl group is more preferable because a stable and higher fluorescence quantum yield can be obtained with respect to excitation light. From the viewpoint of ease of synthesis, it is more preferably a fluorine or cyano group. Further, it is preferable that any one of R ^{8 and} R ⁹ is a cyano group. Durability is improved by introducing a cyano group.

Here, the fluorine-containing aryl group is an aryl group containing fluorine, and examples thereof include a fluorophenyl group, a trifluoromethylphenyl group, and a pentafluorophenyl group. The fluorine-containing heteroaryl group is a fluorine-containing heteroaryl group, and examples thereof include a fluoropyridyl group, a trifluoromethylpyridyl group, and a trifluoropyridyl group. The fluorine-containing alkyl group is an alkyl group containing fluorine, and examples thereof include a trifluoromethyl group and a pentafluoroethyl group.

Further, in the general formula (1), it is preferable that X is CR ⁷ from the viewpoint of light stability. When X is CR ⁷ , the substituent R ⁷ has a great influence on the durability of the compound represented by the general formula (1), that is, the decrease in the emission intensity of this compound with time. Specifically, when R ⁷ is hydrogen, the reactivity of this part is high, so that this part easily reacts with water and oxygen in the air. This causes the decomposition of the compound represented by the general formula (1). Further, when R ⁷ is a substituent such as an alkyl group having a large degree of freedom of movement of the molecular chain, the reactivity is certainly lowered, but the compounds aggregate with time in the color conversion sheet, and the compounds aggregate with time. As a result, the emission intensity is lowered due to the concentration quenching. Therefore, R ⁷ is preferably a group that is rigid, has a small degree of freedom of movement, and does not easily cause aggregation. Specifically, it is a substituted or unsubstituted aryl group, or a substituted or unsubstituted heteroaryl group. It is preferably either.

From the viewpoint of giving a higher fluorescence quantum yield, making it more difficult to thermally decompose, and from the viewpoint of photostability, it is preferable that X is CR ⁷ and R ⁷ is a substituted or unsubstituted aryl group. As the aryl group, a phenyl group, a biphenyl group, a terphenyl group, a naphthyl group, a fluorenyl group, a phenanthryl group and an anthrasenyl group are preferable from the viewpoint of not impairing the emission wavelength.

Furthermore, to increase the photostability of the compound represented by the general formula (1), the carbon of R ⁷ and pyrromethene skeleton - it is necessary to suppress the twisting of the carbon bonds moderately. This is because if the twist is excessively large, the reactivity with the excitation light is increased and the photostability is lowered. From this point of view, R ⁷ is preferably a substituted or unsubstituted phenyl group, a substituted or unsubstituted biphenyl group, a substituted or unsubstituted terphenyl group, or a substituted or unsubstituted naphthyl group, and is preferably substituted or unsubstituted. It is more preferably a phenyl group, a substituted or unsubstituted biphenyl group, or a substituted or unsubstituted terphenyl group. Particularly preferred is a substituted or unsubstituted phenyl group.

Further, R ⁷ is preferably a moderately bulky substituent. When R ⁷ has a certain bulk height, molecular aggregation can be prevented, and as a result, the luminous efficiency and durability of the compound represented by the general formula (1) are further improved.

A more preferable example of such a bulky substituent is the structure of R ⁷ represented by the following general formula (2).

In the general formula (2), r is hydrogen, alkyl group, cycloalkyl group, heterocyclic group, alkenyl group, cycloalkenyl group, alkynyl group, hydroxyl group, thiol group, alkoxy group, alkylthio group, aryl ether group, aryl thio ether. Group, aryl group, heteroaryl group, halogen, cyano group, aldehyde group, carbonyl group, carboxyl group, ester group, carbamoyl group, amino group, nitro group, silyl group, siroxanyl group, boryl group, sulfo group, phosphine oxide group. Selected from the group consisting of. k is an integer of 1 to 3. When k is 2 or more, r may be the same or different.

From the viewpoint of being able to give a higher emission quantum yield, r is preferably a substituted or unsubstituted aryl group. Among these aryl groups, a phenyl group and a naphthyl group are particularly preferable examples. When r is an aryl group, k in the general formula (2) is preferably 1 or 2, and more preferably 2 from the viewpoint of further preventing molecular aggregation. Further, when k is 2 or more, it is preferable that at least one of r is substituted with an alkyl group. As the alkyl group in this case, a methyl group, an ethyl group and a tert-butyl group are particularly preferable examples from the viewpoint of thermal stability.

Further, from the viewpoint of controlling the fluorescence wavelength and absorption wavelength and enhancing the compatibility with the solvent, r is preferably a substituted or unsubstituted alkyl group, a substituted or unsubstituted alkoxy group or a halogen. , Methyl group, ethyl group, tert-butyl group, methoxy group are more preferable. From the viewpoint of dispersibility, a tert-butyl group and a methoxy group are particularly preferable. The fact that r is a tert-butyl group or a methoxy group is more effective in preventing quenching due to aggregation of molecules.

As one of the preferable examples of the compound represented by the general formula (1), R ¹ , R ³ , R ⁴ and R ⁶ may all be the same or different, and are substituted or unsubstituted alkyl groups. Further, there is a case where X is CR ⁷ and R ⁷ is a group represented by the general formula (2). In this case, it is particularly preferable that R ⁷ is a group represented by the general formula (2) in which r is contained as a substituted or unsubstituted phenyl group.

Further, as another preferable example of the compound represented by the general formula (1), R ¹ , R ³ , R ⁴ and R ⁶ may all be the same or different, and the above-mentioned Ar-1 may be used. It is selected from ~ Ar-6, and further, there is a case where X is CR ⁷ and R ⁷ is a group represented by the general formula (2). In this case, R ⁷ is more preferably a group represented by the general formula (2) in which r is contained as a tert-butyl group or a methoxy group, and is represented by the general formula (2) in which r is contained as a methoxy group. It is particularly preferable that it is a group to be produced.

Further, as another preferable example of the compound represented by the general formula (1), R ¹ , R ³ , R ⁴ and R ⁶ may all be the same or different, respectively, and may be substituted or unsubstituted. It is an alkyl group, and R ² and R ⁵ may be the same or different, respectively, and is a substituted or unsubstituted ester group. Further, X is C-R ⁷ and R ⁷ is a general formula. The group represented by (2) may be used. In this case, it is particularly preferable that R ⁷ is a group represented by the general formula (2) in which r is contained as a substituted or unsubstituted phenyl group.

Further, as another preferable example of the compound represented by the general formula (1), R ¹ , R ³ , R ⁴ and R ⁶ may all be the same or different, respectively, and the above-mentioned Ar-1 may be used. ~ Ar-6, and R ² and R ⁵ may be the same or different, respectively, are substituted or unsubstituted ester groups, and X is CR ⁷ and R ⁷ is. There is a case where it is a group represented by the general formula (2). In this case, R ⁷ is more preferably a group represented by the general formula (2) in which r is contained as a tert-butyl group or a methoxy group, and is represented by the general formula (2) in which r is contained as a methoxy group. It is particularly preferable that it is a group to be produced.

An example of the compound represented by the general formula (1) is shown below, but this compound is not limited thereto.

The compound represented by the general formula (1) can be synthesized, for example, by the method described in JP-A-8-509471 and JP-A-2000-208262. That is, the desired pyrromethene-based metal complex can be obtained by reacting the pyrromethene compound and the metal salt in the presence of a base.

Regarding the synthesis of the pyrromethene-boron trifluoride complex, refer to J. Org. Chem. , Vol. 64, No. 21, pp. 7813-7819 (1999), Angew. Chem. , Int. Ed. Engl. , Vol. 36, pp. The compound represented by the general formula (1) can be synthesized with reference to the method described in 1333-1335 (1997) and the like. For example, the compound represented by the following general formula (3) and the compound represented by the general formula (4) are heated in 1,2-dichloroethane in the presence of phosphorus oxychloride, and then the following general formula (5) is used. A method of reacting the represented compound in 1,2-dichloroethane in the presence of triethylamine to obtain the compound represented by the general formula (1) can be mentioned. However, the present invention is not limited to this. Here, R ¹ to R ⁹ are the same as the above description. J represents halogen.

Further, when introducing an aryl group or a heteroaryl group, a method of forming a carbon-carbon bond by using a coupling reaction between a halogenated derivative and a boronic acid or a boronic acid esterified derivative can be mentioned. , Not limited to this. Similarly, when introducing an amino group or a carbazolyl group, for example, a method of forming a carbon-nitrogen bond by using a coupling reaction between a halogenated derivative and an amine or carbazole derivative under a metal catalyst such as palladium is used. However, the present invention is not limited thereto.

The color conversion sheet according to the embodiment of the present invention may appropriately contain other compounds in addition to the compound represented by the general formula (1), if necessary. For example, an assist dopant such as rubrene may be contained in order to further increase the energy transfer efficiency from the excitation light to the compound represented by the general formula (1). Further, when it is desired to add a light emitting color other than the light emitting color of the compound represented by the general formula (1), a desired organic light emitting material, for example, an organic light emitting material such as a coumarin dye or a rhodamine dye may be added. it can. In addition to these organic light emitting materials, known light emitting materials such as inorganic phosphors, fluorescent pigments, fluorescent dyes, and quantum dots can be added in combination.

An example of an organic light emitting material other than the compound represented by the general formula (1) is shown below, but the present invention is not particularly limited thereto.

The quantum dots are not particularly limited, and examples thereof include particles containing at least one selected from the group consisting of group II-VI compounds, group III-V compounds, group IV-VI compounds, and group IV compounds. From the viewpoint of luminous efficiency, the quantum dot phosphor preferably contains a compound containing at least one of Cd and In.

Specific examples of the II-VI group compounds include CdSe, CdTe, CdS, ZnS, ZnSe, ZnTe, ZnO, HgS, HgSe, HgTe, CdSeS, CdSeTe, CdSte, ZnSeS, ZnSeTe, ZnSte, HgSeS, ZnS. , CdZnSe, CdZnTe, CdHgS, CdHgSe, CdHgTe, HgZnS, HgZnSe, HgZnTe, CdZnSeS, CdZnSeTe, CdZnSTe, CdHgSeS, CdHgSeTe, CdHgSeTe, CdHgSe, CdHgSe

Specific examples of the Group III-V compounds include GaN, GaP, GaAs, GaSb, AlN, AlP, AlAs, AlSb, InN, InP, InAs, InSb, COLP, GaNAs, PLACSb, GaPAs, GaPSb, AlNP, AlNAs, AlNSb. , AlPAs, AlPSb, InNP, InNAs, InNSb, InPAs, InPSb, GaAlNP, GaAlNAs, GaAlNSb, GaAlPAs, GaAlPSb, GaInNP, GaInNAs, GaInNSb, GaInPAs, GaInNSb, GaInPAs, GaInPSb, AlInPAs, GaInPSb, InAl

Specific examples of the IV-VI group compounds include SnS, SnSe, SnTe, PbS, PbSe, PbTe, SnSeS, SnSeTe, SnSte, PbSeS, PbSeTe, PbSTe, SnPbS, SnPbSe, SnPbSne, SnPbSe, SnPbSe ..

Specific examples of Group IV compounds include Si, Ge, SiC, SiGe and the like. As the quantum dots, those having a core-shell structure are preferable. By making the band gap of the compound constituting the shell layer wider than the band gap of the compound constituting the core portion, it is possible to further improve the quantum efficiency of the quantum dot phosphor. Examples of the combination of the core portion and the shell layer (core portion / shell layer) include CdSe / ZnS, InP / ZnS, PbSe / PbS, CdSe / CdS, CdTe / CdS, CdTe / ZnS and the like.

Further, the quantum dot phosphor may have a so-called core multi-shell structure in which the shell layer has a multi-layer structure. By laminating one or more shell layers with a narrow bandgap on the core portion with a wide bandgap, and further laminating a shell layer with a wide bandgap on the shell layer, the quantum efficiency of the quantum dot phosphor can be improved. It is possible to further improve.

<Resin contained in color conversion layer and non-color conversion layer>
The color conversion layer and the non-color conversion layer may contain a resin. This resin forms a continuous phase, and may be any material that is excellent in molding processability, transparency, heat resistance, and the like. Examples of the resin include a photocurable resist material having a reactive vinyl group such as acrylic-based, methacrylic-based, vinyl polysilicate-based, polyimide-based, and ring-rubber-based, epoxy resin, and silicone resin (silicone rubber, silicone gel, etc.). Organopolysiloxane cured product (including crosslinked product)), urea resin, fluororesin, polycarbonate resin, acrylic resin, methacrylic resin, polyimide resin, cyclic olefin, polyethylene terephthalate resin, polypropylene resin, polystyrene resin, urethane resin, melamine Known resins such as resins, polyvinyl resins, polyamide resins, phenol resins, polyvinyl alcohol resins, cellulose resins, aliphatic ester resins, aromatic ester resins, aliphatic polyolefin resins and aromatic polyolefin resins can be used. Further, as the resin, these copolymer resins can also be used.

Among these resins, epoxy resin, silicone resin, acrylic resin, ester resin or a mixture thereof can be preferably used from the viewpoint of transparency, and acrylic resin and ester resin are preferably used from the viewpoint of heat resistance. ..

The silicone resin may be either a thermosetting silicone resin or a thermoplastic silicone resin. The thermosetting silicone resin cures at room temperature or a temperature of 50 to 200 ° C., and is excellent in transparency, heat resistance, and adhesiveness.

The thermosetting silicone resin is formed, for example, by a hydrosilylation reaction between a compound containing an alkenyl group bonded to a silicon atom and a compound having a hydrogen atom bonded to a silicon atom. Examples of such a material include alkenyl groups bonded to silicon atoms such as vinyltrimethoxysilane, vinyltriethoxysilane, allyltrimethoxysilane, propenyltrimethoxysilane, norbornenyltrimethoxysilane, and octenyltrimethoxysilane. Containing compounds and hydrogen bonded to silicon atoms such as methylhydrogenpolysiloxane, dimethylpolysiloxane-CO-methylhydrogenpolysiloxane, ethylhydrogenpolysiloxane, methylhydrogenpolysiloxane-CO-methylphenylpolysiloxane, etc. Examples thereof include those formed by a hydrosilylation reaction with a compound having an atom. In addition, as the thermosetting silicone resin, known ones such as those described in JP-A-2010-159411 can be used.

Further, as the thermosetting silicone resin, it is also possible to use a commercially available silicone resin, for example, a silicone encapsulant for general LED applications. Specific examples thereof include OE-6630A / B and OE-6336A / B manufactured by Toray Dow Corning Co., Ltd., SCR-1012A / B and SCR-1016A / B manufactured by Shin-Etsu Chemical Co., Ltd.

It is preferable to add a hydrosilylation reaction retarder such as acetylene alcohol to the thermosetting silicone resin in order to suppress curing at room temperature and prolong the pot life.

Thermoplastic silicone resin is a resin that softens by heating to the glass transition temperature or melting point and exhibits fluidity. Since the thermoplastic silicone resin does not undergo a chemical reaction such as a curing reaction even if it is once heated and softened, it becomes a solid again when it returns to room temperature.

Examples of the thermoplastic silicone resin include commercially available ones, for example, RSN series such as RSN-0805 and RSN-0217 manufactured by Toray Dow Corning.

Among them, since the thermoplastic resin does not contain a reactive component, it can react with the light emitting material and the light emitting material and suppress the deterioration of the light emitting material. Therefore, it is preferable to use a thermoplastic resin for the color conversion layer in the present invention.

<Other additives>
The color conversion layer may contain additives as long as the effects of the present invention are not impaired. Specific examples of additives include light-resistant stabilizers such as dispersion stabilizers, leveling agents, antioxidants, flame retardants, defoaming agents, plasticizers, cross-linking agents, curing agents, and ultraviolet absorbers. , Adhesive aids such as silane coupling agents and the like.

Further, the color conversion layer may contain inorganic particles for the purpose of increasing the efficiency of light extraction from the color conversion layer. Specific examples of the inorganic particles include fine particles composed of glass, titania, silica, alumina, silicone, zirconia, ceria, aluminum nitride, silicon carbide, silicon nitride, barium titanate and the like. These may be used alone or in combination of two or more. Silica, alumina, titania and zirconia are preferable from the viewpoint of easy availability.

<Method of manufacturing color conversion layer>
As a method of providing the color conversion layer in the recess, an ink containing a constituent material of the color conversion layer is prepared, formed on the entire surface of a transparent substrate by a coating method such as a spin coating method, and then patterned by a photolithography method or the like. The color conversion layer may be formed in a pattern by a screen printing method or the like, or the color conversion layer may be formed in a pattern by an inkjet method.

<Color conversion board>
The color conversion substrate includes a partition wall, a green color conversion layer, a red color conversion layer, and a non-color conversion layer on a transparent substrate. The red color conversion layer is formed of an organic light emitting material that absorbs at least blue light and emits red light. The green color conversion layer is formed of an organic light emitting material that absorbs at least blue light and emits green light. The red color conversion layer, the green color conversion layer, and the non-color conversion layer are arranged between the partition walls (recessions). The excitation light may be incident from the transparent substrate side and visually recognized from the side opposite to the transparent substrate, or the excitation light may be incident from the color conversion layer side and visually recognized from the transparent substrate side. The quantum yield when the color conversion substrate is measured as a sample is usually 0.5 or more, preferably 0.7 or more, more preferably 0.7 or more when the color conversion substrate is irradiated with blue light having a peak wavelength of 440 to 460 nm. It is 0.8 or more, more preferably 0.9 or more.

The green color conversion layer according to the embodiment of the present invention comprises a light emitting material (hereinafter referred to as "light emitting material (a1)") that exhibits light emission observed in a region having a peak wavelength of 500 nm or more and less than 580 nm when photoexcited. It is preferable to include it.

Further, the red color conversion layer according to the embodiment of the present invention is a light emitting material (hereinafter referred to as "light emitting material (b1)") that exhibits light emission observed in a region having a peak wavelength of 580 nm or more and 750 nm or less when photoexcited. ), Is preferable. It is more preferable that the light emitting material (a1) and the light emitting material (b1) are light emitting materials excited by light having a wavelength in the range of 400 nm or more and 500 nm or less.

Among them, the green color conversion layer according to the embodiment of the present invention is an organic light emitting material exhibiting light emission observed in a region having a peak wavelength of 500 nm or more and less than 580 nm when photoexcited (hereinafter, “organic light emitting material (a2)). It is more preferable to include).

Further, the red color conversion layer according to the embodiment of the present invention is an organic light emitting material exhibiting light emission observed in a region having a peak wavelength of 580 nm or more and 750 nm or less when photoexcited (hereinafter, “organic light emitting material (b2)). ”), Is more preferable. It is more preferable that the organic light emitting material (a2) and the organic light emitting material (b2) are organic light emitting materials excited by light having a wavelength in the range of 400 nm or more and 500 nm or less.

In general, the larger the energy of excitation light, the more likely it is to cause decomposition of the material. However, the excitation light having a wavelength in the range of 400 nm or more and 500 nm or less has a relatively small excitation energy. Therefore, light emission with good color purity can be obtained without causing decomposition of the light emitting material in the color conversion layer.

The organic light emitting material (a2) contained in the green color conversion layer according to the embodiment of the present invention may be only one type or may be used in combination of two or more. Further, in addition to the organic light emitting material (a2), a light emitting material exhibiting light emission observed in a region having a peak wavelength of 450 nm or more and 530 nm or less when excited by light having a wavelength in the range of 400 nm or more and 500 nm or less may be further contained. ..

Similarly, the organic light emitting material (b2) contained in the red color conversion composition according to the embodiment of the present invention may be only one type or may be used in combination of two or more. Further, the organic light emitting material (a2) may be contained in addition to the organic light emitting material (b2), and by being excited by light having a wavelength in the range of 400 nm or more and 500 nm or less, it is observed in a region having a peak wavelength of 450 nm or more and 530 nm or less. It may further contain a light emitting material that exhibits light emission.

A part of the excitation light having a wavelength in the range of 400 nm or more and 500 nm or less can be used as blue light emission by itself by passing through a non-color conversion portion included in the color conversion substrate according to the embodiment of the present invention. it can. Therefore, by combining a color conversion board having a green color conversion unit, a red color conversion unit, a non-color conversion unit, and a partially driveable blue light source, it is possible to display blue, green, and red in a single color and white. Therefore, full-color display of the display becomes possible. That is, green can be displayed by partially lighting only the blue light source located in the green color conversion unit, and red can be displayed by partially lighting only the blue light source located in the red color conversion unit. It is possible to display blue by partially turning on only the blue light source located in the non-color conversion unit.

Examples of the organic luminescent material (a2) include coumarin derivatives such as coumarin 6, coumarin 7, and coumarin 153, cyanine derivatives such as indocyanine green, fluorescein derivatives such as fluorescein, fluorescein isothiocyanate, and carboxyfluorescein diacetate, and phthalocyanine such as phthalocyanine green. Derivatives, perylene derivatives such as diisobutyl-4,10-dicyanoperylene-3,9-dicarboxylate, other pyromethene derivatives, stillben derivatives, oxazine derivatives, naphthalimide derivatives, pyrazine derivatives, benzoimidazole derivatives, benzoxazole derivatives, benzo Suitable compounds include thiazole derivatives, imidazole pyridine derivatives, azole derivatives, compounds having a fused aryl ring such as anthracene, derivatives thereof, aromatic amine derivatives, and organic metal complex compounds. However, the organic light emitting material (a2) is not particularly limited to these.

Among the compounds of the organic light emitting material (a2), the pyrromethene derivative is a particularly suitable compound because it gives a high emission quantum yield and has good durability. As the pyrromethene derivative, for example, the compound represented by the general formula (1) is preferable because it exhibits high luminescence with high color purity.

Examples of the organic light emitting material (b2) include cyanine derivatives such as 4-dicyanomethylene-2-methyl-6- (p-dimethylaminostyryl) -4H-pyran, rhodamine B, rhodamine 6G, rhodamine 101, sulfodamine 101 and the like. Rhodamine derivatives, pyridine derivatives such as 1-ethyl-2- (4- (p-dimethylaminophenyl) -1,3-butadienyl) -pyridinium-parklorate, N, N'-bis (2,6-diisopropylphenyl) Perylene derivatives such as -1,6,7,12-tetraphenoxyperylene-3,4: 9,10-bisdicarboimide, as well as porphyrin derivatives, pyromethene derivatives, oxazine derivatives, pyrazine derivatives, naphthacene and dibenzodiindeno Suitable compounds include compounds having a fused aryl ring such as perylene, derivatives thereof, and organic metal complex compounds. However, the organic light emitting material (b2) is not particularly limited to these.

Among the compounds of the organic light emitting material (b2), the pyrromethene derivative is a particularly suitable compound because it gives a high emission quantum yield and has good durability. As the pyrromethene derivative, for example, the compound represented by the general formula (1) is preferable because it exhibits high luminescence with high color purity.

The content of the organic light emitting material (a2) contained in the green color conversion layer according to the embodiment of the present invention includes the molar extinction coefficient of the compound, the emission quantum yield and the absorption intensity at the excitation wavelength, and the color conversion sheet to be produced. Although it depends on the thickness and transmittance, it is preferably 5.0 × 10 ^-6 mol / m ² or more and 5.0 × 10 ^-3 mol / m ² or less per unit area of the color conversion substrate, preferably 1.0. × 10 ^-5 mol / m ² or more and 1.0 × 10 ^-3 mol / m ² or less is more preferable, and 2.0 × 10 ^-5 mol / m ² or more and 1.0 × 10 ^-3 mol / m It is more preferably ² or less, and even more preferably 5.0 × 10 ^-5 mol / m ² or more and 1.0 × 10 ^-3 mol / m ² or less.

Further, the content of the organic light emitting material (b2) contained in the red color conversion layer according to the embodiment of the present invention includes the molar extinction coefficient of the compound, the emission quantum yield and the absorption intensity at the excitation wavelength, and the color conversion sheet to be produced. Although it depends on the thickness and transmittance of the material, it is preferably 5.0 × 10 ^-6 mol / m ² or more and 5.0 × 10 ^-3 mol / m ² or less per unit area of the color conversion substrate. It is more preferably 0 × 10 ^-5 mol / m ² or more and 1.0 × 10 ^-3 mol / m ² or less, and 3.0 × 10 ^-5 mol / m ² or more and 1.0 × 10 ^-3 mol / m / m. It is more preferably m ² or less, and even more preferably 5.0 × 10 ^-5 mol / m ² or more and 1.0 × 10 ^-3 mol / m ² or less.

<Color filter>
Further, the color conversion substrate in the present invention preferably has a color filter. The color filter is a layer for transmitting a specific wavelength range of visible light, making the transmitted light a desired hue, and improving the color purity of the transmitted light. When converting blue light with the color conversion layer, the blue light from the excitation light source cannot be sufficiently cut, so that the converted light is mixed with blue light, and as a result, the converted light cannot be selectively obtained, resulting in high color purity. I can't get it. Therefore, by using a color filter, it is possible to selectively cut only blue light and extract only converted light, and the color purity is improved. The color filter used in the present invention can be formed by using a material used for a flat panel display such as a liquid crystal display. In recent years, a pigment-dispersed material in which a pigment is dispersed in a photoresist is often used. A blue color filter that transmits a wavelength of 400 nm to 550 nm, a green color filter that transmits a wavelength of 500 nm to 600 nm, a yellow color filter that transmits a wavelength of 500 nm or more, or a red color filter that transmits a wavelength of 600 nm or more is used. Is preferable. Further, the color filters may be laminated apart from the color conversion unit, or may be integrated and laminated. Further, a color filter may be formed on the color conversion substrate, or a color filter substrate may be produced separately from the color conversion substrate and superposed. Further, it is preferable that the color conversion unit and the color filter are stacked in this order from the light source.

The blue color filter is preferably formed on the non-color conversion portion, the green color filter is preferably formed on the green color conversion layer, and the red color filter is preferably formed on the red color conversion layer. Further, the yellow color filter is preferably formed on the green color conversion layer and the red color conversion layer. The color filter, the non-color conversion unit, the green color conversion layer, and the red color conversion layer may be directly laminated, or may have an air layer or a resin layer between them. As the resin of the resin layer, the resin described in <Resin contained in the color conversion layer and the non-color conversion layer> can be appropriately used.

<Display>
The display having the color conversion substrate according to the present invention includes at least a partially driven blue light source. As the light source, an organic electroluminescent element, a blue LED light source, or the like can be used. Further, a color filter may be included in addition to the light source, and an optical film such as a prism film or a diffusion film may be included.

The display having the color conversion substrate according to the present invention has a minimum of three sub-pixels in which the green color conversion unit is a green sub-pixel, the red color conversion unit is a red sub-pixel, and the non-color conversion unit is a blue sub-pixel. It constitutes one pixel which is a unit. FIG. 7 shows a partition wall width 71, a blue sub-pixel width 74, a green sub-pixel width 73, and a red sub-pixel width 72 when the partition wall shape is striped.

The blue sub-pixel width, the green sub-pixel width, and the red sub-pixel width are preferably 300 μm or less, more preferably 200 μm or less, and further preferably 150 μm or less. The blue sub-pixel width, the green sub-pixel width, and the red sub-pixel width are preferably 10 μm or more, more preferably 20 μm or more, and further preferably 30 μm or less. When the blue sub-pixel width, the green sub-pixel width, and the red sub-pixel width are 300 μm or less, a higher-definition display can be obtained. Further, when the blue sub-pixel width, the green sub-pixel width, and the red sub-pixel width are 10 μm or more, a color conversion substrate with good yield can be manufactured.

The partition wall width is preferably 30 μm or less, more preferably 20 μm or less, and further preferably 10 μm or less. Further, the partition wall width is preferably 5 μm or more. When the partition wall width is in the above range, a display having high brightness and good color purity can be obtained.

<Display chromaticity / brightness>
The chromaticity and brightness of the display having the color conversion substrate according to the present invention can be measured by a luminance meter or the like with the display lit. For example, the measurement can be performed according to the organic EL display module measuring method "EIAJ ED-2810" defined by the Japan Electronics Machinery Manufacturers Association. The chromaticity when the display is displayed in white can be expressed as chromaticity coordinates (x, y) according to the "XYZ color system" defined by the International Commission on Illumination (CIE). The chromaticity x when displayed in white is preferably 0.25 or more, more preferably 0.28 or more, and further preferably 0.30 or more. Further, it is preferably 0.35 or less, and more preferably 0.33 or less. The chromaticity y when displayed in white is preferably 0.25 or more, more preferably 0.28 or more, and further preferably 0.30 or more. Further, it is preferably 0.36 or less, and more preferably 0.34 or less. The brightness of the display is preferably 100 nits or more, more preferably 150 nits or more, further preferably 200 nits or more, further preferably 250 nits or more, and particularly preferably 300 nits or more.

Hereinafter, the present invention and its effects will be described with reference to specific examples, but the examples do not limit the scope of application of the present invention.

(Measurement of area Sr, area Sg, area Sn)
For one of the arbitrary 5 cm × 5 cm regions in the color conversion substrates produced in Examples and Comparative Examples described later, the total area of the red color conversion layer Sr (cm ² ) and the total area of the green color conversion layer Sg ( cm ² ) and the total area of the non-color conversion layer Sn (cm ² ) were obtained. The measurement results of each example are shown in Tables 1 to 3. Further, in the first embodiment, the total area of the red color conversion layer existing on the color conversion substrate, the total area of the green color conversion layer, and the total area of the non-color conversion layer are also expressed in the formulas (A) and (B). It was confirmed that the relationship was satisfied.

(Saturation / brightness evaluation)
The displays produced in Examples and Comparative Examples described later were driven at 10 mA / cm ² for each color, and the chromaticity and brightness were measured with a Topcon spectroradiometer SR-LEDW.

Hereinafter, an example of manufacturing the color conversion substrate of the present invention and an organic EL display to which the color conversion substrate is applied will be described. The organic EL display was formed with 160 × 120 × RGB pixels.

(Example 1)
(Making a color conversion board)
1. 1. Fabrication of partition wall VPA204 / P5.4-2 (manufactured by Nippon Steel Chemical Co., Ltd.) is spin-coated on a transparent substrate (Corning 1737 glass: 50 x 50 x 1.1 mm) as a partition wall material to form a striped pattern. It was exposed to ultraviolet rays through a photomask, developed with a 2% aqueous sodium carbonate solution, and then baked at 200 ° C. to form a transparent partition wall (thickness 30 μm) pattern. The partition wall width was 10 μm, the red sub-pixel width was 110 μm, the green sub-pixel width was 110 μm, and the blue sub-pixel width was 80 μm.

2. 2. Preparation of Red Color Conversion Layer An ink was prepared by mixing a red pyrromethene derivative RD-1 (0.01% by weight) and polymethyl methacrylate (manufactured by Kuraray) (4% by weight) in a propylene glycol monomethyl acetate solvent. The prepared ink was adhered to the surface of the red color conversion layer region in a nitrogen atmosphere using an inkjet method. Then, the substrate was dried at 200 ° C. for 30 minutes to prepare a red color conversion layer having a film thickness of 25 μm.

3. 3. Preparation of green color conversion layer Mix green pyromethene derivative GD-1 (0.01% by weight) and polymethyl methacrylate (manufactured by Kuraray) (4% by weight) in a propylene glycol monomethyl acetate solvent, and dissolve the ink. Was prepared. The prepared ink was adhered to the surface of the green color conversion layer region in a nitrogen atmosphere by using an inkjet method. Then, the substrate was dried at 200 ° C. for 30 minutes to prepare a green color conversion layer having a film thickness of 25 μm.

4. Preparation of Color Filter The black coloring composition was prepared by mixing and stirring a mixture having the following composition and filtering it with a filter having a pore size of 1.0 μm.
Carbon black dispersion: Mikuni Color Co., Ltd. (TPBK-2016) 29.8 parts by weight Resin: V259-ME (Nippon Steel Chemical Co., Ltd.) (solid content 56.1% by weight) 10.3 parts by weight Monomer: DPHA ( Nippon Kayaku Co., Ltd.) 2.58 parts by weight Initiator: OXE-02 (manufactured by Ciba Specialty Chemicals) 0.86 parts by weight Solvent: propylene glycol monomethyl ether acetate 92.0 parts by weight Dispersant: DISPER BYK 21116 (manufactured by Ciba Specialty Chemicals) Big Chemy Japan Co., Ltd.) 2.6 parts by weight.

The above black coloring composition was applied using a spin coating method. The formed film was patterned by a photolithography method to prepare a black matrix having a line pattern having a line width of 10 μm, a pitch of 0.33 mm, and a film thickness of 2 μm.

The yellow coloring composition was prepared by mixing and stirring a mixture having the following composition and filtering it with a filter having a pore size of 1.0 μm.
Yellow pigment: Pigment Yellow 150 7.5 parts by weight Resin: Aronix M7100 (manufactured by Toa Synthetic Chemical Industry Co., Ltd.) 5.5 parts by weight Monomer: Dipentaesterol hexaacrylate (manufactured by Nippon Kayaku Co., Ltd.) 5.0 parts by weight started Agent: OXE-02 (manufactured by Ciba Specialty Chemicals) 0.86 parts by weight Solvent: Eukerester EEP (manufactured by Dow Chemical Co., Ltd.) 13.5 parts by weight propylene glycol monomethyl ether acetate 41.0 parts by weight Dispersant: DISPER BYK 21116 (manufactured by Big Chemie Japan Co., Ltd.) 2.3 parts by weight.

The above yellow coloring composition was applied using a spin coating method. The formed film was patterned by a photolithography method to prepare a yellow color filter having a thickness of 2 μm on the red color conversion layer and the green color conversion layer.

From the above, a color conversion substrate having a non-color conversion unit that transmits blue light and a yellow color filter on the red conversion layer and the green color conversion layer was produced.

5. Fabrication of Organic EL Substrate The TFTs were arranged on the organic EL substrate corresponding to the pixel shape patterned on the color conversion substrate prepared above. Subsequently, an Ag film was formed on the organic EL substrate by a sputtering method, and then an ITO transparent conductive film was formed in a pattern with a thickness of 165 nm. The obtained substrate was ultrasonically cleaned with Semicoclean 56 (trade name, manufactured by Furuuchi Chemical Co., Ltd.) for 15 minutes, and then washed with ultrapure water. Immediately before manufacturing the device, this substrate was subjected to UV-ozone treatment for 1 hour, installed in a vacuum vapor deposition apparatus, and evacuated until the degree of vacuum in the apparatus became 5 × 10 ^-4 Pa or less. By the resistance heating method, HAT-CN ₆ was first deposited at 5 nm as a hole injection layer, and HT-1 was deposited at 50 nm as a hole transport layer. Next, as a light emitting layer, H-1 as a host material and BD-1 as a blue dopant material were deposited to a thickness of 20 nm so that the doping concentration was 5% by weight. Further, ET-1 was used as the electron transport layer and 2E-1 was used as the donor material, and the layers were laminated to a thickness of 35 nm so that the vapor deposition rate ratio of ET-1 and 2E-1 was 1: 1. Next, after depositing 2E-1 at 0.5 nm as an electron injection layer, magnesium and silver were co-deposited at 60 nm to form a cathode, and Alq ₃ was deposited to a thickness of 60 nm. A sealed glass substrate was adhered to the substrate after the film formation to obtain a partially driveable top emission type organic EL substrate. The size of the blue light source for the red subpixel was 300 μm × 100 μm, the size of the blue light source for the green subpixel was 300 μm × 100 μm, and the size of the blue light source for the blue subpixel was 300 μm × 70 μm. Each blue light source was prepared so as to be arranged in a grid pattern with an interval of 10 μm from the adjacent blue light sources on the top, bottom, left, and right.

6. Production of Organic EL Display A display was produced by laminating the color conversion substrate and the organic EL substrate prepared as described above. The chromaticity and brightness of each color were measured using the display.

(Examples 2 to 9, Comparative Example 1)
The color conversion substrate, the organic EL substrate, and the organic EL display are operated in the same manner as in the first embodiment except that the width of each sub-pixel and the size of the blue light source corresponding to each sub-pixel are as shown in Tables 1 and 2. Made. The chromaticity and brightness measurement results of the obtained organic EL display are shown in Tables 1 and 2. RD-1, GD-1, BD-1, HAT-CN ₆ , HT-1, H-1, ET-1, and 2E-1 are the compounds shown below. In Examples 2 to 9, the total area of the red color conversion layer existing on the color conversion substrate, the total area of the green color conversion layer, and the total area of the non-color conversion layer are also expressed in the formulas (A) and (B). It was confirmed that the relationship was satisfied. Further, it was confirmed that the formula (C-1) was satisfied for Examples 3 to 9. On the other hand, in Comparative Example 1, the total area of the red color conversion layer existing on the color conversion substrate, the total area of the green color conversion layer, and the total area of the non-color conversion layer are also expressed in the formulas (A) and (B). It was confirmed that the relationship was not satisfied.

(Examples 10 and 11)
A color conversion substrate, an organic EL substrate, and an organic EL display were produced by the same operations as in Example 1 except that the width of each sub-pixel and the size of the blue light source corresponding to each sub-pixel were set as shown in Table 3. Table 3 shows the chromaticity and brightness measurement results of the obtained organic EL display. In Examples 10 and 11, the total area of the red color conversion layer existing on the color conversion substrate, the total area of the green color conversion layer, and the total area of the non-color conversion layer are also expressed in the formulas (A) and (B). And it was confirmed that the relation of the equation (C-2) was satisfied.

The color conversion substrate according to the present invention and the display using the same can achieve both preferable chromaticity and sufficient brightness.

11 Display 12 Organic EL substrate 13 Organic EL element 14 Transparent substrate 15 Encapsulating layer 16 Color conversion substrate 17N Non-color conversion layer 17G Green color conversion layer 17R Red color conversion layer 18B Blue color filter 18Y Yellow color filter 19 Partition 110 Substrate 21 Display 22 LED board 23 LED
24 Transparent substrate 26 Color conversion substrate 27N Non-color conversion layer 27G Green color conversion layer 27R Red color conversion layer 28B Blue color filter 28Y Yellow color filter 29 Partition 210 Board B Non-color conversion layer G Green color conversion layer R Red color conversion layer 71 Partition width 72 Red sub-pixel width 73 Green sub-pixel width 74 Blue sub-pixel width

Claims

A color conversion substrate having a partition wall on the substrate and having a green color conversion layer, a red color conversion layer, and a non-color conversion layer containing no phosphor in a region partitioned by the partition wall. When the color conversion layer and the red color conversion layer contain a light emitting material and the area of the green color conversion layer is Sg, the area of the red color conversion layer is Sr, and the area of the non-color conversion layer is Sn, Sg. A color conversion substrate in which Sr and Sn satisfy the relationships of the following formulas (A) and (B).
Formula (A) Sn <Sg
Equation (B) Sn <Sr
The color conversion substrate according to claim 1, wherein the area Sg, the area Sr, and the area Sn satisfy the relationship of the following formula (C-1).
Equation (C-1) Sn <Sg <Sr
The color conversion substrate according to claim 1, wherein the area Sg, the area Sr, and the area Sn satisfy the relationship of the following formula (C-2).
Equation (C-2) Sn <Sr <Sg
The color conversion substrate according to any one of claims 1 to 3, wherein the area Sg, the area Sr, and the area Sn satisfy at least one of the relationships of the following formulas (D) and (E).
Equation (D) 1.0 <Sg / Sn ≦ 5.0
Equation (E) 1.0 <Sr / Sn ≦ 5.0
The color conversion substrate according to any one of claims 1 to 4, wherein the planar shape of the partition wall is striped.
The color conversion substrate according to any one of claims 1 to 4, wherein the partition wall has a grid-like planar shape.
The color conversion substrate according to any one of claims 1 to 6, wherein the light emitting material includes the following light emitting materials (a1) and (b1).
(A1) Light emitting material exhibiting light emission observed in a region having a peak wavelength of 500 nm or more and less than 580 nm when photoexcited (b1) Light emission observed in a region having a peak wavelength of 580 nm or more and 750 nm or less by photoexcitation Luminescent material that exhibits
The color conversion substrate according to any one of claims 1 to 7, wherein the light emitting materials (a1) and (b1) are the following organic light emitting materials (a2) and (b2), respectively.
(A2) Organic light emitting material exhibiting light emission observed in a region having a peak wavelength of 500 nm or more and less than 580 nm by photoexcitation (b2) Observed in a region having a peak wavelength of 580 nm or more and 750 nm or less by photoexcitation Organic luminescent material that emits light
The color according to claim 8, wherein the content of the organic light emitting material (a2) per unit area is 5.0 × 10 -6 mol / m 2 or more and 5.0 × 10 -3 mol / m 2 or less. Conversion board.
The color according to claim 7, wherein the content of the organic light emitting material (b2) per unit area is 5.0 × 10 -6 mol / m 2 or more and 5.0 × 10 -3 mol / m 2 or less. Conversion board.
The color conversion substrate according to any one of claims 1 to 10, wherein the light emitting material is a pyrromethene derivative.
The color conversion substrate according to claim 11, wherein the pyrromethene derivative is a compound represented by the general formula (1).

(X is CR 7 or N. R 1 to R 9 may be the same or different, respectively, hydrogen, alkyl group, cycloalkyl group, heterocyclic group, alkenyl group, cycloalkenyl group, alkynyl group, Hydroxyl group, thiol group, alkoxy group, alkylthio group, aryl ether group, aryl thio ether group, aryl group, heteroaryl group, halogen, cyano group, aldehyde group, carbonyl group, carboxyl group, ester group, carbamoyl group, amino group, nitro It is selected from a fused ring and an aliphatic ring formed between a group, a silyl group, a siloxanyl group, a boryl group, a sulfo group, a phosphine oxide group, and an adjacent substituent.)
The color conversion substrate according to claim 12, wherein in the general formula (1), X is CR 7 and R 7 is a group represented by the general formula (2).

(R is hydrogen, alkyl group, cycloalkyl group, heterocyclic group, alkenyl group, cycloalkenyl group, alkynyl group, hydroxyl group, thiol group, alkoxy group, alkylthio group, aryl ether group, aryl thioether group, aryl group, hetero Selected from the group consisting of aryl groups, halogens, cyano groups, aldehyde groups, carbonyl groups, carboxyl groups, ester groups, carbamoyl groups, amino groups, nitro groups, silyl groups, siloxanyl groups, boryl groups, sulfo groups and phosphine oxide groups. .K is an integer of 1 to 3. When k is 2 or more, r may be the same or different.)
A display including the color conversion substrate according to any one of claims 1 to 13 and a plurality of partially driveable blue light sources.
The display according to claim 14, wherein the blue light source is a light emitting diode.
The display according to claim 14 or 15, wherein the blue light source is an organic electroluminescent device in which an organic layer exists between an anode and a cathode and emits light by electric energy.