Light-emitting element, display device, and quantum dot dispersion

Abstract

A red light-emitting element (5R) comprises: a lower electrode (22); an upper electrode (25); and a red light-emitting layer (24 REM) provided between the lower electrode (22) and the upper electrode (25) and including a silicon oxide containing at least one among a hydroxy group and an alkoxy group and a plurality of quantum dots (QD), wherein ((amount of hydroxy group + amount of alkoxy group) / (amount of Si element)) × 100 [%] in the red light-emitting layer (24 REM) is 1 [%] to 200 [%].

Description

Light-emitting element, display device, and quantum dot dispersion

[0001] The present disclosure relates to a light-emitting device, a display device, and a quantum dot dispersion.

[0002] In recent years, quantum dot light-emitting diodes (QLEDs), which are light-emitting elements containing quantum dots, and display devices equipped with QLEDs have been attracting a great deal of attention because of their ability to achieve low power consumption, thinness, high image quality, and the like.

[0003] In the field of QLEDs, active research is being conducted on quantum dot dispersions used to form the light-emitting layers of QLEDs.

[0004] For example, Patent Document 1 describes a light-emitting device having a light-emitting layer containing a semiconductor matrix and quantum dots.

[0005] Japanese Patent Publication "Patent Publication No. 2011-502333"

[0006] Patent Document 1 describes a case where the semiconductor matrix contained in the light-emitting layer is made of an inorganic material.

[0007] When the semiconductor matrix contained in the light-emitting layer is made of an inorganic material, cracks and distortions occur in the inorganic film, which can lead to a decrease in the light-emitting characteristics and reliability of the light-emitting element. In addition, the thickness of the semiconductor matrix in the light-emitting layer can be made thicker than necessary, which can increase the driving voltage of the light-emitting element.

[0008] An aspect of the present disclosure aims to provide a light-emitting element and a display device having a light-emitting layer that can suppress deterioration of light-emitting characteristics, deterioration of reliability, and an increase in driving voltage, and a quantum dot dispersion liquid that can form such a light-emitting layer.

[0009] In order to solve the above-mentioned problems, the light-emitting element of the present disclosure includes an anode, a cathode, and a light-emitting layer including silicon oxide containing at least one of a hydroxy group and an alkoxy group and a plurality of quantum dots, the light-emitting layer being provided between the anode and the cathode, wherein ((amount of hydroxy groups+amount of alkoxy groups) / (amount of Si element))×100[%] in the light-emitting layer is equal to or greater than 1[%] and equal to or less than 200[%].

[0010] In order to solve the above-mentioned problems, the display device of the present disclosure includes the light-emitting element.

[0011] In order to solve the above-mentioned problems, the quantum dot dispersion liquid of the present disclosure includes a plurality of quantum dots, at least one of a plurality of dialkoxysilane compounds and a plurality of trialkoxysilane compounds, and a solvent.

[0012] According to one aspect of the present disclosure, it is possible to provide a light-emitting element and a display device having a light-emitting layer that can suppress deterioration of light-emitting characteristics, deterioration of reliability, and an increase in driving voltage, and a quantum dot dispersion liquid that can form such a light-emitting layer.

[0013] 4 is a plan view showing a schematic configuration of a display device of embodiment 1. FIG. 5 is a cross-sectional view showing a schematic configuration of a display region of the display device of embodiment 1. FIG. 6 is a cross-sectional view showing a schematic configuration of a red light-emitting device provided in the display device of embodiment 1, including a partially enlarged view of portion A. FIG. 7 is a diagram showing the number of Si elements, the number of hydroxy groups + the number of alkoxy groups, and the value of ((number of hydroxy groups + number of alkoxy groups) / (number of Si elements)) × 100 [%] in a single alkoxysilane compound containing one Si element or a compound in which various alkoxysilane compounds containing one Si element are bonded. FIG. 8 is a diagram for explaining a region formed between quantum dots when two adjacent quantum dots are arranged close to each other among a plurality of quantum dots contained in a red light-emitting layer provided in the red light-emitting device shown in FIG. 3. FIG. 9 is a diagram showing a preparation process of a quantum dot dispersion liquid used in a process of forming a red light-emitting layer provided in the red light-emitting device shown in FIG. 3.

[0014] The following describes an embodiment of the present disclosure with reference to Figures 1 to 6. For the sake of convenience, components having the same functions as those described in a specific embodiment will be denoted by the same reference numerals, and their description may be omitted.

[0015] First Embodiment FIG. 1 is a plan view showing a schematic configuration of a display device 1 according to a first embodiment.

[0016] As shown in Fig. 1, the display device 1 includes a frame area NDA and a display area DA. The display area DA of the display device 1 includes a plurality of pixels PIX, each of which includes a red subpixel RSP, a green subpixel GSP, and a blue subpixel BSP. In this embodiment, a case in which one pixel PIX is configured with a red subpixel RSP, a green subpixel GSP, and a blue subpixel BSP will be described as an example, but this is not limiting. For example, one pixel PIX may include subpixels of other colors in addition to the red subpixel RSP, the green subpixel GSP, and the blue subpixel BSP.

[0017] FIG. 2 is a cross-sectional view showing a schematic configuration of the display area DA of the display device 1 of the first embodiment.

[0018] As shown in Figure 2, in the display area DA of the display device 1, a barrier layer 3, a thin film transistor layer 4 including a transistor TR, a red light-emitting element 5R, a green light-emitting element 5G, a blue light-emitting element 5B and a bank 23, a sealing layer 6, and a functional film 39 are provided on a substrate 12 in this order from the substrate 12 side.

[0019] The red subpixel RSP provided in the display area DA of the display device 1 includes a red light-emitting element 5R (light-emitting element), the green subpixel GSP provided in the display area DA of the display device 1 includes a green light-emitting element 5G (light-emitting element), and the blue subpixel BSP provided in the display area DA of the display device 1 includes a blue light-emitting element 5B (light-emitting element). The red light-emitting element 5R included in the red subpixel RSP includes an anode which is the lower electrode 22, a functional layer 24R including a red light-emitting layer, and a cathode which is the upper electrode 25. The green light-emitting element 5G included in the green subpixel GSP includes an anode which is the lower electrode 22, a functional layer 24G including a green light-emitting layer, and a cathode which is the upper electrode 25. The blue light-emitting element 5B included in the blue subpixel BSP includes an anode which is the lower electrode 22, a functional layer 24B including a blue light-emitting layer, and a cathode which is the upper electrode 25. In the display device 1 shown in Figure 2, an example is given in which a functional layer 24R including a red light-emitting layer, a functional layer 24G including a green light-emitting layer, and a functional layer 24B including a blue light-emitting layer are provided for each sub-pixel of each color, but this is not limited to this, and one or more layers, for example, a hole injection layer, a hole transport layer, an electron injection layer, and an electron transport layer, which are included in the functional layer 24R including a red light-emitting layer, the functional layer 24G including a green light-emitting layer, and the functional layer 24B including a blue light-emitting layer, may be provided as a common layer (one layer) for each of the red sub-pixel RSP, the green sub-pixel GSP, and the blue sub-pixel BSP.

[0020] The substrate 12 may be, for example, a resin substrate made of a resin material such as polyimide, or a glass substrate. In this embodiment, since the display device 1 is a flexible display device, a case where a resin substrate made of a resin material such as polyimide is used as the substrate 12 will be described as an example, but this is not limiting. If the display device 1 is a non-flexible display device, a glass substrate can be used as the substrate 12.

[0021] The barrier layer 3 is a layer that prevents foreign substances such as water and oxygen from penetrating into the transistor TR, the red light-emitting element 5R, the green light-emitting element 5G, and the blue light-emitting element 5B, and can be composed of, for example, a silicon oxide film, a silicon nitride film, a silicon oxynitride film, or a laminated film of these, formed by the CVD method.

[0022] The transistor TR portion of the thin film transistor layer 4 including the transistor TR includes the semiconductor film SEM and doped semiconductor films SEM′ and SEM″, an inorganic insulating film 16, a gate electrode G, an inorganic insulating film 18, an inorganic insulating film 20, a source electrode S and a drain electrode D, and a planarization film 21, and the portion of the thin film transistor layer 4 including the transistor TR other than the transistor TR portion includes the inorganic insulating film 16, the inorganic insulating film 18, the inorganic insulating film 20, and the planarization film 21.

[0023] The semiconductor films SEM, SEM', and SEM'' may be made of, for example, low-temperature polysilicon (LTPS) or an oxide semiconductor (for example, an In-Ga-Zn-O based semiconductor). In this embodiment, the case where the transistor TR has a top-gate structure will be described as an example, but the present invention is not limited to this, and the transistor TR may also have a bottom-gate structure.

[0024] The gate electrode G and the source electrode S and drain electrode D can be formed of a single layer or a multilayer film of a metal containing at least one of aluminum, tungsten, molybdenum, tantalum, chromium, titanium, and copper, for example.

[0025] The inorganic insulating films 16, 18 and 20 can be formed of, for example, a silicon oxide film, a silicon nitride film, a silicon oxynitride film, or a laminated film of these films, which are formed by the CVD method.

[0026] The planarizing film 21 can be made of a coatable organic material such as polyimide or acrylic.

[0027] The red light-emitting element 5R includes an anode, which is a lower electrode 22 above the planarization film 21, a functional layer 24R including a red light-emitting layer, and a cathode, which is an upper electrode 25. The green light-emitting element 5G includes an anode, which is a lower electrode 22 above the planarization film 21, a functional layer 24G including a green light-emitting layer, and a cathode, which is an upper electrode 25. The blue light-emitting element 5B includes an anode, which is a lower electrode 22 above the planarization film 21, a functional layer 24B including a blue light-emitting layer, and a cathode, which is an upper electrode 25. The insulating bank 23 covering the edge of the anode, which is the lower electrode 22, can be formed, for example, by applying an organic material such as polyimide or acrylic and then patterning it by photolithography. Although the present embodiment will be described taking the case where the bank 23 is provided as an example, the bank 23 may not be provided.

[0028] The sealing layer 6 is a light-transmitting film, and can be composed of, for example, an inorganic sealing film 26 that covers the cathode, which is the upper electrode 25, an organic film 27 that is above the inorganic sealing film 26, and an inorganic sealing film 28 that is above the organic film 27. The sealing layer 6 prevents foreign substances such as water and oxygen from penetrating into the red light-emitting element 5R, the green light-emitting element 5G, and the blue light-emitting element 5B.

[0029] The inorganic sealing films 26 and 28 are each an inorganic film, and may be formed, for example, by a CVD method using a silicon oxide film, a silicon nitride film, a silicon oxynitride film, or a laminated film thereof. The organic film 27 is a light-transmitting organic film with a planarizing effect, and may be formed, for example, using a coatable organic material such as acrylic. The organic film 27 may also be formed, for example, by an inkjet method. In this embodiment, the sealing layer 6 is formed of two inorganic films and one organic film disposed between the two inorganic films. However, the stacking order of the two inorganic films and one organic film is not limited to this. Furthermore, the sealing layer 6 may be formed solely of an inorganic film, solely of an organic film, one inorganic film and two organic films, or two or more inorganic films and two or more organic films.

[0030] The functional film 39 is a film having at least one of an optical compensation function, a touch sensor function, and a protection function, for example.

[0031] Fig. 3 is a cross-sectional view showing a schematic configuration of a red light-emitting element 5R provided in the display device 1 of embodiment 1, including a partially enlarged view of portion A. Fig. 4 is a diagram showing the number of Si elements, the number of hydroxy groups + the number of alkoxy groups, and the value of ((number of hydroxy groups + number of alkoxy groups) / (number of Si elements)) × 100[%] in a single alkoxysilane compound containing one Si element or a compound in which various alkoxysilane compounds containing one Si element are combined. Fig. 5 is a diagram for explaining a region K formed between quantum dots QD1 and QD2 when adjacent two quantum dots QD1 and QD2 are arranged close to each other among the multiple quantum dots QD contained in the red light-emitting layer 24REM provided in the red light-emitting element 5R shown in Fig. 3 .

[0032] 3, the red light-emitting element 5R includes an anode serving as the lower electrode 22, a cathode serving as the upper electrode 25, and a red light-emitting layer 24REM provided between the anode serving as the lower electrode 22 and the cathode serving as the upper electrode 25. The red light-emitting layer 24REM includes silicon oxide containing at least one of hydroxy groups and alkoxy groups, and a plurality of quantum dots QDs, and the value of ((amount of hydroxy groups + amount of alkoxy groups) / (amount of Si element))×100[%] in the red light-emitting layer 24REM is equal to or greater than 1[%] and equal to or less than 200[%]. The value of ((amount of hydroxy groups + amount of alkoxy groups) / (amount of Si element))×100[%] described above can be obtained by comparing the amount of detection unit derived from the measurement device, such as peak intensity, signal intensity, or count number, obtained by measurement using a measurement device. The number of Si elements, the number of hydroxyl groups + the number of alkoxyl groups, and the value of ((number of hydroxyl groups + number of alkoxyl groups) / (number of Si elements)) × 100 [%] in the various alkoxysilane compounds containing one Si element or in the compound in which various alkoxysilane compounds containing one Si element are bonded, shown in FIG. 4, are examples in which the detection unit amount derived from the above-mentioned device is the count number. The red light-emitting layer 24REM includes a plurality of quantum dots QD and a matrix MR. Note that the matrix MR may be filled in the red light-emitting layer 24REM, but as shown in FIG. 5, if there is a portion of the multiple quantum dots QD contained in the red light-emitting layer 24REM that fills at least the region K between two adjacent first quantum dots QD1 and second quantum dots QD2, it may be considered as a matrix. The region K shown in FIG. 5 is a region surrounded by two straight lines (common circumscribing lines) circumscribing the peripheries of the first quantum dot QD1 and the second quantum dot QD2 and the opposing peripheries of the first quantum dot QD1 and the second quantum dot QD2 in a cross-sectional view. 5, even if the first quantum dot QD1 is close to the second quantum dot QD2, the region K can exist. ２The matrix MR may include a continuous film having an area of ​​at least 1000 nm. A continuous film means a film that is not divided by materials other than the material that constitutes the continuous film in one plane. The continuous film may be an integrated film that is connected without interruption by chemical bonds of the materials that constitute the matrix MR.

[0033] Examples of various alkoxysilane compounds containing one Si element shown in FIG. 4 are shown in the following (Chemical Formula 1) to (Chemical Formula 10), (Chemical Formula 13), and (Chemical Formula 14). The following (Chemical Formula 1) is a general formula of a trialkoxysilane compound containing a functional group capable of coordinating to quantum dots (QDs). Z in the following (Chemical Formula 1) is a functional group capable of coordinating to quantum dots (QDs), and can be appropriately selected from a thiol group, an amine group, a carboxylic acid group, a phosphine group, etc. depending on the material of the quantum dots (QDs). In the following (Chemical Formula 1), R is C ｎ H ２ｎ (where C is a carbon atom, H is a hydrogen atom, and n is a natural number of 1 or more), Si is silicon, and OR is an alkoxy group. 3-(mercaptopropyl)trimethoxysilane (MPS) shown in the following (chemical formula 2) is a silane represented by the following (chemical formula 1) in which Z is a thiol group and R is C ｎ H ２ｎ Department C ３ H ６and this is an example where all three alkoxy groups represented by OR are methoxy groups. Hexyltrimethoxysilane shown in (Chemical Formula 3) below and trimethoxyphenylsilane shown in (Chemical Formula 4) below are examples of trialkoxysilane compounds that do not contain a functional group capable of coordinating to quantum dots (QDs). Diethoxydimethylsilane shown in (Chemical Formula 5) below, dimethoxydiphenylsilane shown in (Chemical Formula 6) below, and dimethoxymethylphenylsilane shown in (Chemical Formula 7) below are examples of dialkoxysilane compounds that do not contain a functional group capable of coordinating to quantum dots (QDs). 3-mercaptopropyl(dimethoxy)methylsilane shown in (Chemical Formula 8) below is an example of a dialkoxysilane compound that contains a functional group capable of coordinating to quantum dots (QDs). Methoxytrimethylsilane shown in (Chemical Formula 9) below and methoxytriphenylsilane shown in (Chemical Formula 10) below are examples of monoalkoxysilane compounds that do not contain a functional group capable of coordinating to quantum dots (QDs). Tetramethoxysilane (tetramethyl orthosilicate (TMOS)) shown in the following (Chemical Formula 13) and tetrabutoxysilane shown in the following (Chemical Formula 14) are examples of tetraalkoxysilane compounds. 1,1,3,3-Tetramethyldisiloxane shown in the following (Chemical Formula 11) and hexamethyldisiloxane shown in the following (Chemical Formula 12) are examples of monoalkoxysilane derivatives. Monoalkoxysilane derivatives have a moiety in which two silicon atoms share one oxygen atom. This moiety is cleaved when a predetermined energy such as heat is supplied or during the process of silicon oxide formation, and behaves as a monoalkoxysilane. Therefore, monoalkoxysilane compounds and monoalkoxysilane derivatives that do not contain a functional group capable of coordinating to quantum dots (QDs) can be suitably used as capping agents for hydroxyl groups and alkoxy groups. Furthermore, the above-mentioned dialkoxysilane compound and trialkoxysilane compound containing a functional group capable of coordinating to the quantum dots QD are ligands of the quantum dots QD, and the above-mentioned tetraalkoxysilane compound and the dialkoxysilane compound and trialkoxysilane compound not containing a functional group capable of coordinating to the quantum dots QD are crosslinking agents.

[0034] When a silicon oxide film is formed, sequential reactions of highly reactive groups contained in various alkoxysilane compounds, such as alkoxy groups and hydroxy groups, can cause the film to shrink, resulting in film cracking and distortion, which can lead to a decrease in the light-emitting characteristics and reliability of the light-emitting element. Furthermore, sequential reactions of highly reactive groups contained in various alkoxysilane compounds, such as alkoxy groups and hydroxy groups, can cause the film to be formed thicker than necessary, which can increase the driving voltage of the light-emitting element. Therefore, in this embodiment, the red light-emitting layer 24REM provided in the red light-emitting element 5R includes silicon oxide containing at least one of hydroxy groups and alkoxy groups and a plurality of quantum dots QDs, and the ratio ((amount of hydroxy groups + amount of alkoxy groups) / (amount of Si element)) × 100[%] in the red light-emitting layer 24REM is set to be 1[%] or more and 200[%] or less. The fact that the residual ratio of hydroxyl groups and alkoxy groups in the red light-emitting layer 24REM is within the above-mentioned predetermined range, i.e., 1% to 200%, means that the above-mentioned successive reactions are suppressed to some extent, and a red light-emitting element 5R and a display device 1 can be realized that include the red light-emitting layer 24REM, which can suppress deterioration of light-emitting characteristics, deterioration of reliability, and an increase in driving voltage. In a light-emitting layer, for example, the value of ((amount of hydroxyl groups + amount of alkoxy groups) / (amount of Si element)) × 100% in the red light-emitting layer 24REM is 200%, which means that there are two excess reactive groups per Si element, i.e., two reactive groups per molecule of alkoxysilane. In such a case, since the distance between these two reactive groups is the intramolecular distance, the reactive groups are densely present in the red light-emitting layer 24REM, making it relatively susceptible to reaction. Therefore, in terms of suppressing any additional reactions that may occur in the red light-emitting layer 24REM, it is preferable that the value of ((amount of hydroxy groups+amount of alkoxy groups) / (amount of Si element))×100[%] does not exceed 200[%], that is, it is preferable that the value be 200[%] or less, and it is further preferable that the value be 150[%] or less.Furthermore, when the value of ((amount of hydroxyl groups + amount of alkoxyl groups) / (amount of Si element))×100[%] in the light-emitting layer, for example, the red light-emitting layer 24REM, is 100[%], this means, for example, that there is one extra reactive group per Si element, that is, one reactive group per alkoxysilane molecule. When the value of ((amount of hydroxyl groups + amount of alkoxyl groups) / (amount of Si element))×100[%] in the light-emitting layer, for example, the red light-emitting layer 24REM, is less than 100[%], the number of reactive groups per alkoxysilane molecule becomes less than one, and the red light-emitting layer 24REM is in a state where reactive groups are sparsely distributed. Therefore, in order to further suppress any additional reactions that may occur in the red light-emitting layer 24REM, the value of ((amount of hydroxyl groups + amount of alkoxyl groups) / (amount of Si element))×100[%] is preferably 100[%] or less, and more preferably 50[%] or less. Furthermore, when the value of ((amount of hydroxy groups + amount of alkoxy groups) / (amount of Si element)) × 100[%] in the light-emitting layer, for example, the red light-emitting layer 24REM, falls below 50[%], there is one reactive group per four alkoxysilane molecules, and therefore the reactive groups are highly likely to be sparse both within a molecule and between adjacent molecules. Therefore, in order to further suppress any additional reactions that may occur in the red light-emitting layer 24REM, the value of ((amount of hydroxy groups + amount of alkoxy groups) / (amount of Si element)) × 100[%] is preferably 25[%] or less, and more preferably 15[%] or less. On the other hand, because a plurality of alkoxysilane compounds form an irregular three-dimensional matrix, there is a problem of structural interference between physical molecules, and therefore it is theoretically difficult to make the value of ((amount of hydroxy groups+amount of alkoxy groups) / (amount of Si element))×100[%] in the light-emitting layer, for example, the red light-emitting layer 24REM, completely 0[%], and 1[%] or more or 5[%] or more remains.

[0035] In order to ensure that ((amount of hydroxy groups+amount of alkoxy groups) / (amount of Si element))×100[%] in the red light-emitting layer 24REM is 1[%] or more and 200[%] or less, it is preferable to form the matrix MR included in the red light-emitting layer 24REM using at least one of a dialkoxysilane compound containing a plurality of one Si element (e.g., see the above (Chemical Formula 5) to (Chemical Formula 8)) and a trialkoxysilane compound containing a plurality of one Si element (e.g., see the above (Chemical Formula 2) to (Chemical Formula 4)), as can be seen from the number of Si elements, the number of hydroxy groups+the number of alkoxy groups, and the value of ((number of hydroxy groups+number of alkoxy groups) / (number of Si element))×100[%] in the various alkoxysilane compounds containing one Si element alone or in the compounds in which various alkoxysilane compounds containing one Si element are bonded, as shown in FIG. 4 . Furthermore, as shown in FIG. 4, even when a trialkoxysilane compound containing a large number of alkoxy groups (for example, see the above (Chemical Formula 2) to (Chemical Formula 4)) is used, the number of the large number of alkoxy groups can be easily reduced by using the above-mentioned capping agent, for example, a monoalkoxysilane compound that does not contain a functional group capable of coordinating to the quantum dots (QD), together.

[0036] In the red light-emitting layer 24REM, ((amount of hydroxy groups+amount of alkoxy groups) / (amount of Si element))×100[%] may be 1% or more and 150% or less, 1% or more and 100% or less, 1% or more and 50% or less, 1% or more and 25% or less, or 1% or more and 15% or less. In addition, ((amount of hydroxy groups+amount of alkoxy groups) / (amount of Si element))×100[%] in the red light-emitting layer 24REM may be 5% or more as long as it is 200% or less.

[0037] In this embodiment, the matrix MR included in the red light-emitting layer 24REM was formed using a plurality of 3-mercaptopropyl(dimethoxy)methylsilanes shown in the above (Chemical Formula 8), which are an example of a dialkoxysilane compound containing a coordinating functional group for the quantum dots QDs, and which are ligands for the quantum dots QDs. As shown in the partially enlarged view of portion A in FIG. 3 , the red light-emitting layer 24REM includes molecules containing coordinating functional groups for the quantum dots QDs formed by successive reactions of alkoxy groups and hydroxy groups of a plurality of 3-mercaptopropyl(dimethoxy)methylsilanes, and the ratio ((amount of hydroxy groups + amount of alkoxy groups) / (amount of Si element))×100[%] in the molecules containing coordinating functional groups for the quantum dots QDs formed by successive reactions of alkoxy groups and hydroxy groups of a plurality of 3-mercaptopropyl(dimethoxy)methylsilanes is 1[%] or more and 25[%] or less.

[0038] In this embodiment, in the red light-emitting layer 24REM, 3-mercaptopropyl(dimethoxy)methylsilane compounds shown in the above (Chemical Formula 8), which are an example of a dialkoxysilane compound containing a coordinating functional group for the quantum dots QDs and serve as ligands for the quantum dots QDs, are connected horizontally in two dimensions to form a roughly monolayer network. Furthermore, the quantum dots QDs are covered with a minimal amount of silicon oxide. Therefore, the red light-emitting element 5R equipped with the red light-emitting layer 24REM can suppress degradation of light-emitting characteristics, degradation of reliability, and an increase in driving voltage. Note that, without being limited thereto, in addition to 3-mercaptopropyl(dimethoxy)methylsilane shown above (Chemical Formula 8), which is an example of a dialkoxysilane compound containing a functional group capable of coordinating to quantum dots QDs and which is a ligand of quantum dots QDs, a monoalkoxysilane compound or monoalkoxysilane derivative which does not contain a functional group capable of coordinating to quantum dots QDs and which is the capping agent for the hydroxy group and alkoxy group described above may be added as appropriate, and at least one of a tetraalkoxysilane compound which is the crosslinking agent described above, a dialkoxysilane compound which does not contain a functional group capable of coordinating to quantum dots QDs, and a trialkoxysilane compound which does not contain a functional group capable of coordinating to quantum dots QDs may be added as appropriate together with the capping agent for the hydroxy group and alkoxy group described above.

[0039] Instead of the 3-mercaptopropyl(dimethoxy)methylsilane shown in the above (Chemical Formula 8) used in this embodiment, only 3-(mercaptopropyl)trimethoxysilane (MPS) shown in the above (Chemical Formula 2), which is an example of a trialkoxysilane compound containing a coordinating functional group for quantum dots QDs and is a ligand for quantum dots QDs, may be used. Furthermore, without being limited thereto, in addition to 3-(mercaptopropyl)trimethoxysilane (MPS), a monoalkoxysilane compound or monoalkoxysilane derivative not containing a coordinating functional group for quantum dots QDs, which is the capping agent for the hydroxyl group and alkoxy group described above, may be appropriately added. In addition to the capping agent for the hydroxyl group and alkoxy group described above, at least one of a tetraalkoxysilane compound, which is the crosslinking agent described above, a dialkoxysilane compound not containing a coordinating functional group for quantum dots QDs, and a trialkoxysilane compound not containing a coordinating functional group for quantum dots QDs may also be appropriately added.

[0040] In this embodiment, a case where a first charge transport layer 24HT is provided between the anode, which is the lower electrode 22, and the red light-emitting layer 24REM, and a second charge transport layer 24ET is provided between the cathode, which is the upper electrode 25, and the red light-emitting layer 24REM, is described as an example, but this is not limited to this, and at least one of the first charge transport layer 24HT and the second charge transport layer 24ET may be omitted. In this embodiment, a case where a hole injection layer and a hole transport layer are provided in this order from the anode, which is the lower electrode 22, as the first charge transport layer 24HT is described as an example, but this is not limited to this, and the first charge transport layer 24HT may be composed of either a hole transport layer or a hole injection layer. In addition, in this embodiment, the second charge transport layer 24ET will be described as an example in which an electron injection layer and an electron transport layer are provided in this order from the cathode side, which is the upper electrode 25, but the present invention is not limited to this, and the second charge transport layer 24ET may be configured with either an electron transport layer or an electron injection layer. Note that, of the red light-emitting element 5R, green light-emitting element 5G, and blue light-emitting element 5B shown in FIG. 2, the red light-emitting element 5R will be described as an example here, but the green light-emitting element 5G and blue light-emitting element 5B can also be configured in the same way as the red light-emitting element 5R.

[0041] As shown in FIG. 3 , a first charge transport layer 24HT in contact with the red light-emitting layer 24REM is provided between the anode, which is the lower electrode 22, and the red light-emitting layer 24REM. The red light-emitting layer 24REM has a thickness corresponding to the distance from the first charge transport layer 24HT to the quantum dot QD that is closest to the first charge transport layer 24HT among the multiple quantum dots QD, and in a part P2 on the first charge transport layer 24HT side, ((amount of hydroxy groups+amount of alkoxy groups) / (amount of Si element))×100[%] is 1[%] or more and 25[%] or less.

[0042] As shown in FIG. 3 , a second charge transport layer 24ET in contact with the red light-emitting layer 24REM is provided between the cathode, which is the upper electrode 25, and the red light-emitting layer 24REM. The red light-emitting layer 24REM has a thickness corresponding to the distance from the second charge transport layer 24ET to the quantum dot QD that is closest to the second charge transport layer 24ET among the multiple quantum dots QD, and in a portion P1 on the second charge transport layer 24ET side of the red light-emitting layer 24REM, ((amount of hydroxy groups+amount of alkoxy groups) / (amount of Si elements))×100[%] is 1[%] or more and 25[%] or less.

[0043] The red light-emitting layer 24REM of the red light-emitting element 5R shown in FIG. 3 includes quantum dots QDs. The quantum dots QDs may have, for example, a core structure, a core / shell structure, a core / shell / shell structure, or a shell structure with a continuously varying core / shell ratio. The shell QDs may partially cover the core QDs, but it is more preferable for the shell QDs to completely cover the core QDs. The core material of the quantum dots QDs may be, for example, a II-VI group semiconductor crystal such as MgS, MgSe, MgTe, CaS, CaSe, CaTe, BaS, BaSe, BaTe, ZnS, ZnSe, ZnTe, CdS, CdSe, CdTe, PbS, PbSe, HgS, HgSe, or HgTe; a III-V group semiconductor crystal such as GaAs, GaP, InN, InAs, InP, or InSb; or Ga ３ S ２ , Ga ２ Se ３ , In ２ S ３ , In ２ Se ３ Crystals of III-VI group semiconductors such as CuInGaS, AgInGaS, CuInGaS, AgInGaZnS, CuInGaSe, AgInGaSe, etc., crystals of I-III-VI group semiconductors such as C and Si, crystals of IV group semiconductors such as CsPbI ３ , CsPbBr ３ , CsPbCl ３ The shell material can be made of a semiconductor crystal with a perovskite structure such as the above. The shell material is selected from the same material group as the core material, and is preferably one that has a lattice constant close to that of the core material and a larger band gap than the core material.

[0044] 2 and 3 may be of either a top-emission type or a bottom-emission type. The red light-emitting element 5R, the green light-emitting element 5G, and the blue light-emitting element 5B have a stack structure in which the cathode, which is the upper electrode 25, is disposed above the anode, which is the lower electrode 22. To form the red light-emitting element 5R, the green light-emitting element 5G, and the blue light-emitting element 5B as a top-emission type, the anode, which is the lower electrode 22, should be formed from an electrode material that reflects visible light, and the cathode, which is the upper electrode 25, should be formed from an electrode material that transmits visible light. To form the bottom-emission type, the anode, which is the lower electrode 22, should be formed from an electrode material that transmits visible light, and the cathode, which is the upper electrode 25, should be formed from an electrode material that reflects visible light. On the other hand, in the case of an inverted stack structure in which the upper electrode 25, that is, the anode, is arranged as a layer above the lower electrode 22, that is, the cathode, in order to make it a top emission type, the lower electrode 22, that is, the cathode, can be formed from an electrode material that reflects visible light, and the upper electrode 25, that is, the anode, can be formed from an electrode material that transmits visible light, and in order to make it a bottom emission type, the lower electrode 22, that is, the cathode, can be formed from an electrode material that transmits visible light, and the upper electrode 25, that is, the anode, can be formed from an electrode material that reflects visible light.

[0045] The electrode material that reflects visible light is not particularly limited as long as it can reflect visible light and has electrical conductivity. Examples of the electrode material that reflects visible light include metal materials such as Al, Mg, Li, and Ag, alloys of the metal materials, laminates of the metal materials and transparent metal oxides (e.g., indium tin oxide, indium zinc oxide, indium gallium zinc oxide, etc.), and laminates of the alloys and the transparent metal oxides.

[0046] On the other hand, the electrode material that transmits visible light is not particularly limited as long as it can transmit visible light and has conductivity, and examples thereof include transparent metal oxides (e.g., indium tin oxide, indium zinc oxide, indium gallium zinc oxide, etc.), thin films made of metal materials such as Al and Ag, and nanowires made of metal materials such as Al and Ag.

[0047] FIG. 6 is a diagram showing a process for preparing a quantum dot dispersion liquid used in a process for forming the red light-emitting layer 24REM provided in the red light-emitting element 5R shown in FIG.

[0048] Based on FIG. 6, a process for preparing a quantum dot dispersion liquid containing a plurality of quantum dots QD, at least one of a plurality of dialkoxysilane compounds and a plurality of trialkoxysilane compounds, and a solvent will be described.

[0049] As shown in step S1 of Fig. 6, a first solution containing 3-mercaptopropyl(dimethoxy)methylsilane, which is a dialkoxysilane compound containing a coordinating functional group for quantum dots and shown in (Chemical Formula 8) above, and DMF as a solvent, and a second solution in which quantum dots QDs are dispersed in octane as a solvent, are stirred for, for example, 8 hours or more and 12 hours or less, thereby precipitating a solid containing quantum dots QDs and 3-mercaptopropyl(dimethoxy)methylsilane in an intermediate layer, as shown in step S2 of Fig. 6. In step S3 of Fig. 6, the upper and lower layers of the solid containing quantum dots QDs and 3-mercaptopropyl(dimethoxy)methylsilane were extracted, and only the solid containing quantum dots QDs and 3-mercaptopropyl(dimethoxy)methylsilane was extracted. Thereafter, as shown in step S4 of FIG. 6, the solid containing the quantum dots QDs and 3-mercaptopropyl(dimethoxy)methylsilane is re-dispersed in, for example, toluene to obtain a quantum dot dispersion liquid containing a plurality of quantum dots QDs, a plurality of dialkoxysilane compounds, and a solvent.

[0050] In this embodiment, an example will be described in which a quantum dot dispersion is prepared using 3-mercaptopropyl(dimethoxy)methylsilane shown in the above (chemical formula 8), which is a dialkoxysilane compound containing a functional group capable of coordinating to quantum dots. However, the present invention is not limited to this. A quantum dot dispersion may be prepared using 3-(mercaptopropyl)trimethoxysilane (MPS) shown in the above (chemical formula 2), which is a trialkoxysilane compound containing a functional group capable of coordinating to quantum dots. A quantum dot dispersion may also be prepared using a dialkoxysilane compound that does not contain a functional group capable of coordinating to quantum dots or a trialkoxysilane compound that does not contain a functional group capable of coordinating to quantum dots. Furthermore, a quantum dot dispersion may be prepared by adding the above-mentioned capping agent or the above-mentioned crosslinking agent together with the above-mentioned capping agent.

[0051] In the quantum dot dispersion liquid shown in FIG. 6, as shown in the above (Chemical Formula 8), the dialkoxysilane compound containing a functional group capable of coordinating to the quantum dots has a functional group capable of coordinating to the quantum dots QD and a C ｎ H ２ｎ The trialkoxysilane compound includes a moiety (C is a carbon element, H is a hydrogen element, and n is a natural number of 1 or more) and a dialkoxysilane group, and as shown in the above (Chemical Formula 1), the trialkoxysilane compound includes a coordinating functional group to the quantum dot QD and a C ｎ H ２ｎ The quantum dot dispersion liquid shown in FIG. 6 includes a C moiety (C is a carbon element, H is a hydrogen element, and n is a natural number of 1 or more) and a trialkoxysilane group. The functional group capable of coordinating with the quantum dots QDs can be appropriately selected from a thiol group, an amine group, a carboxylic acid group, a phosphine group, etc., depending on the material of the quantum dots QDs. In the quantum dot dispersion liquid shown in FIG. 6, the alkoxy group contained in each of the dialkoxysilane compound and the trialkoxysilane compound is preferably selected from a methoxy group, an ethoxy group, a propoxy group, and a butoxy group, taking reactivity into consideration. Furthermore, in the quantum dot dispersion liquid shown in FIG. 6, the C of the dialkoxysilane compound containing a functional group capable of coordinating with the quantum dots QDs or the trialkoxysilane compound containing a functional group capable of coordinating with the quantum dots QDs ｎ H ２ｎIn consideration of dispersibility in a solvent or the like, the number n in the unit is preferably 1 or more and 20 or less, and more preferably 3 or more and 18 or less.

[0052] Furthermore, in the quantum dot dispersion liquid described above, when the total weight of the alkoxysilane compound containing at least one of a plurality of dialkoxysilane compounds and the plurality of trialkoxysilane compounds is W1 and the total weight of the plurality of quantum dots is W2, (W1 / W2) × 100 [%] is preferably 10 [%] or more and 100 [%] or less, in consideration of efficiently suppressing a decrease in light-emitting characteristics, a decrease in reliability, and an increase in driving voltage, and is more preferably 20 [%] or more and 100 [%] or less, or 10 [%] or more and less than 40 [%], or 10 [%] or more and less than 20 [%]. When the value of (W1 / W2) × 100[%] is 10[%] or more and less than 20[%], at least one of a dialkoxysilane compound having a coordinating functional group for the quantum dots QDs, which are ligands of the quantum dots QDs, and a trialkoxysilane compound having a coordinating functional group for the quantum dots QDs, can be formed along the shape of the quantum dots QDs, for example, along the shape of the shell QDS of the quantum dots QDs. When the value of (W1 / W2) × 100[%] is 10[%] or more and less than 15[%], the surface coverage of the quantum dots QDs by at least one of a dialkoxysilane compound having a coordinating functional group for the quantum dots QDs, which are ligands of the quantum dots QDs, and a trialkoxysilane compound having a coordinating functional group for the quantum dots QDs, is approximately 100%, meaning that there is almost no excess. When the value of (W1 / W2) × 100[%] is 15[%] or more and less than 20[%], there is an excess. On the other hand, when the value of (W1 / W2) × 100[%] is 20[%] or more and 100[%] or less, at least one of a dialkoxysilane compound containing a coordinating functional group for the quantum dots QDs, which are ligands of the quantum dots QDs, and a trialkoxysilane compound containing a coordinating functional group for the quantum dots QDs, forms the matrix MR portion, and the formed matrix MR portion does not depend on the shape of the quantum dots QDs, in other words, the matrix MR portion is formed without being influenced by the shape of the shell QDS of the quantum dots QDs. Such a shape of the matrix MR portion can be realized because the matrix MR portion substantially fills the surface of the quantum dots QDs and the surface of the shell QDS of the quantum dots QDs, and the matrix MR portion is further formed on top of that.When the value of (W1 / W2) × 100[%] is 20[%] or more and less than 40[%], the surplus is contained in a large amount. Furthermore, from the viewpoint of protecting the quantum dots QD with a minimum amount and improving the reliability of the light-emitting layer, the value of (W1 / W2) × 100[%] is preferably 10[%] or more and less than 20[%]. When it is desired to further protect the quantum dots QD and ensure, for example, resistance to atmospheric exposure and coating processes such as solvent resistance, the value of (W1 / W2) × 100[%] is preferably 20[%] or more and 100[%] or less.

[0053] 6, in the step of preparing the second solution in which the quantum dots QDs are dispersed in the solvent octane, an organic substance containing a functional group capable of coordinating with the quantum dots QDs, i.e., an organic ligand, may be used to ensure the dispersibility of the quantum dots QDs in octane. In such a case, when the quantum dot dispersion liquid shown in FIG. 6 contains X moles of the organic substance containing a functional group capable of coordinating with the quantum dots QDs, Y moles of a dialkoxysilane compound, and Z moles of a trialkoxysilane compound, ((Y + Z) / (X + Y + Z)) × 100 [%] is preferably 20 [%] or more and 100 [%] or less, and more preferably 40 [%] or more and 100 [%] or less.

[0054] As the dialkoxysilane compound or trialkoxysilane compound, a dialkoxysilane compound not containing a functional group capable of coordinating to the quantum dots QD or a trialkoxysilane compound not containing a functional group capable of coordinating to the quantum dots QD may be used, but from the viewpoint of protecting the quantum dots QD, it is preferable to use a dialkoxysilane compound containing a functional group capable of coordinating to the quantum dots QD or a trialkoxysilane compound containing a functional group capable of coordinating to the quantum dots QD. As the dialkoxysilane compound containing a functional group capable of coordinating to the quantum dots QD, it is preferable to use any of 3-(2-Aminoethylamino)propyl dimethoxy methyl silane, 3-Aminopropyl dimethoxy methyl silane, 3-Aminopropyl diethoxy methyl silane, and 3-Mercaptopropyl (dimethoxy) methyl silane. Furthermore, as the trialkoxysilane compound containing a functional group capable of coordinating to quantum dots (QD), it is preferable to use any one of 3-(2-Aminoethylamino)propyl trimethoxy silane, [3-(6-Aminohexylamino)propyl] trimethoxy silane, 3-(2-Aminoethylamino)propyl triethoxy silane, (3-Mercaptopropyl) triethoxy silane, 3-Aminopropyl trimethoxy silane, 1-[3-(Trimethoxysilyl)propyl] urea, and 1-[3-(Triethoxysilyl)propyl] urea.

[0055] The quantum dot dispersion liquid shown in Fig. 6 may contain the capping agent described above, and may contain a monoalkoxysilane compound or the monoalkoxysilane derivative described above as the capping agent. When the quantum dot dispersion liquid shown in Fig. 6 contains Y moles of a dialkoxysilane compound, Z moles of a trialkoxysilane compound, and A moles of a monoalkoxysilane compound as a capping agent, (A / (Y+Z+A)) x 100 [%] is preferably 30 [%] or more and 70 [%] or less, and more preferably 30 [%] or more and less than 50 [%], or 50 [%] or more and 70 [%] or less.

[0056] The monoalkoxysilane compound serving as a capping agent may be a compound containing one alkoxy group and three non-reactive groups that do not react with the hydroxyl or alkoxy groups contained in the dialkoxysilane compound or trialkoxysilane compound. Furthermore, in consideration of reactivity, the alkoxy group contained in the monoalkoxysilane compound serving as a capping agent is preferably selected from the group consisting of a methoxy group, an ethoxy group, a propoxy group, and a butoxy group.

[0057] [Additional Notes] The present disclosure is not limited to the above-described embodiments, and various modifications are possible within the scope of the claims. Embodiments obtained by appropriately combining the technical means disclosed in different embodiments are also included in the technical scope of the present disclosure. Furthermore, new technical features can be formed by combining the technical means disclosed in each embodiment.

[0058] The present disclosure can be used in light-emitting devices, display devices, and quantum dot dispersions.

[0059] 1 display device 4 thin film transistor layer 5R red light emitting element (light emitting element) 5G green light emitting element (light emitting element) 5B blue light emitting element (light emitting element) 22 lower electrode 23 bank 24R functional layer including red light emitting layer 24G functional layer including green light emitting layer 24B functional layer including blue light emitting layer 24REM red light emitting layer 24HT first charge transport layer 24ET second charge transport layer 25 upper electrode 26, 28 inorganic sealing film 27 organic film 39 functional film QD quantum dot MR matrix P1 part of red light emitting layer on the second charge transport layer side P2 part of red light emitting layer on the first charge transport layer side PIX pixel RSP red subpixel GSP green subpixel BSP blue subpixel DA display area NDA frame area

Claims

1. An anode, a cathode, a silicon oxide containing at least one of a hydroxy group and an alkoxy group, and a plurality of quantum dots, and a light-emitting layer provided between the anode and the cathode, wherein ((the amount of hydroxy group + the amount of alkoxy group) / (the amount of Si element))×100 [%] in the light-emitting layer is 1 [%] or more and 200 [%] or less. A light-emitting device.

2. The light-emitting device according to claim 1, wherein ((the amount of hydroxy group + the amount of alkoxy group) / (the amount of Si element))×100 [%] in the light-emitting layer is 1 [%] or more and 150 [%] or less.

3. The light-emitting device according to claim 2, wherein ((the amount of hydroxy group + the amount of alkoxy group) / (the amount of Si element))×100 [%] in the light-emitting layer is 1 [%] or more and 100 [%] or less.

4. The light-emitting device according to claim 3, wherein ((the amount of hydroxy group + the amount of alkoxy group) / (the amount of Si element))×100 [%] in the light-emitting layer is 1 [%] or more and 50 [%] or less.

5. The light-emitting device according to claim 4, wherein ((the amount of hydroxy group + the amount of alkoxy group) / (the amount of Si element))×100 [%] in the light-emitting layer is 1 [%] or more and 25 [%] or less.

6. The light-emitting device according to claim 5, wherein ((the amount of hydroxy group + the amount of alkoxy group) / (the amount of Si element))×100 [%] in the light-emitting layer is 1 [%] or more and 15 [%] or less.

7. The light-emitting device according to any one of claims 1 to 6, wherein ((the amount of hydroxy group + the amount of alkoxy group) / (the amount of Si element))×100 [%] in the light-emitting layer is 5 [%] or more.

8. The light-emitting layer includes a molecule containing a coordinating functional group to the quantum dots, and ((the amount of hydroxy group + the amount of alkoxy group) / (the amount of Si element))×100 [%] in the molecule containing a coordinating functional group to the quantum dots is 1 [%] or more and 25 [%] or less. The light-emitting device according to any one of claims 1 to 7.

9. The light-emitting device according to claim 8, wherein the coordinating functional group to the quantum dots is any one of a thiol group, an amine group, a carboxylic acid group, and a phosphine group.

10. A hole transport layer in contact with the light-emitting layer or a hole injection layer in contact with the light-emitting layer is provided between the anode and the light-emitting layer, and ((the amount of hydroxy groups + the amount of alkoxy groups) / (the amount of Si element))×100 [%] in a part on the hole transport layer side or a part on the hole injection layer side of the light-emitting layer having a thickness corresponding to the distance from the hole transport layer or the hole injection layer to the quantum dot closest to the hole transport layer or the hole injection layer among the plurality of quantum dots is 1 [%] or more and 25 [%] or less. The light-emitting element according to any one of claims 1 to 7.

11. An electron transport layer in contact with the light-emitting layer or an electron injection layer in contact with the light-emitting layer is provided between the cathode and the light-emitting layer, and ((the amount of hydroxy groups + the amount of alkoxy groups) / (the amount of Si element))×100 [%] in a part on the electron transport layer side or a part on the electron injection layer side of the light-emitting layer having a thickness corresponding to the distance from the electron transport layer or the electron injection layer to the quantum dot closest to the electron transport layer or the electron injection layer among the plurality of quantum dots is 1 [%] or more and 25 [%] or less. The light-emitting element according to any one of claims 1 to 7.

12. A display device including the light-emitting element according to any one of claims 1 to 11.

13. A quantum dot dispersion liquid including a plurality of quantum dots, at least one of a plurality of dialkoxysilane compounds and a plurality of trialkoxysilane compounds, and a solvent.

14. The alkoxy groups contained in each of the dialkoxysilane compound and the trialkoxysilane compound are selected from methoxy group, ethoxy group, propoxy group, and butoxy group. The quantum dot dispersion liquid according to claim 13.

15. Each of the dialkoxysilane compound and the trialkoxysilane compound contains a coordinating functional group to the quantum dot. The quantum dot dispersion liquid according to claim 13 or 14.

16. The dialkoxysilane compound includes a coordinating functional group to the quantum dot, a C ｎ H ２ｎ portion (where C is a carbon element, H is a hydrogen element, and n is a natural number of 1 or more), and a dialkoxysilane group. The trialkoxysilane compound includes a coordinating functional group to the quantum dot, a C ｎ H ２ｎ portion (where C is a carbon element, H is a hydrogen element, and n is a natural number of 1 or more), and a trialkoxysilane group. The quantum dot dispersion liquid according to claim 15.

17. The n of the C of the dialkoxysilane compound containing a coordinating functional group to the quantum dot or the trialkoxysilane compound containing a coordinating functional group to the quantum dot ｎ H ２ｎ part is 1 or more and 20 or less, and the quantum dot dispersion liquid according to claim 16.

18. The n of the C of the dialkoxysilane compound containing a coordinating functional group to the quantum dot or the trialkoxysilane compound containing a coordinating functional group to the quantum dot ｎ H ２ｎ part is 3 or more and 18 or less, and the quantum dot dispersion liquid according to claim 16.

19. The coordinating functional group to the quantum dot is any one of a thiol group, an amine group, a carboxylic acid group, and a phosphine group. The quantum dot dispersion liquid according to any one of claims 15 to 18.

20. When the total weight of the alkoxysilane compound containing at least one of the plurality of dialkoxysilane compounds and the plurality of trialkoxysilane compounds is W1 and the total weight of the plurality of quantum dots is W2, (W1 / W2)×100 [%] is 10 [%] or more and 100 [%] or less. The quantum dot dispersion liquid according to any one of claims 13 to 19.

21. The quantum dot dispersion liquid according to claim 20, wherein (W1 / W2)×100 [%] is 10 [%] or more and less than 40 [%].

22. The quantum dot dispersion liquid according to claim 21, wherein (W1 / W2)×100 [%] is 10 [%] or more and less than 20 [%].

23. When the total weight of the alkoxysilane compound containing at least one of the plurality of dialkoxysilane compounds and the plurality of trialkoxysilane compounds is W1 and the total weight of the plurality of quantum dots is W2, (W1 / W2)×100 [%] is 20 [%] or more and 100 [%] or less. The quantum dot dispersion liquid according to any one of claims 13 to 19.

24. Each of the dialkoxysilane compound and the trialkoxysilane compound contains a coordinating functional group to the quantum dot. When it contains X moles of an organic substance containing a coordinating functional group to the quantum dot, Y moles of the dialkoxysilane compound, and Z moles of the trialkoxysilane compound, ((Y + Z) / (X + Y + Z))×100 [%] is 20 [%] or more and 100 [%] or less. The quantum dot dispersion liquid according to any one of claims 13 to 19.

25. Each of the dialkoxysilane compound and the trialkoxysilane compound contains a coordinating functional group to the quantum dot. When it contains X moles of an organic substance containing a coordinating functional group to the quantum dot, Y moles of the dialkoxysilane compound, and Z moles of the trialkoxysilane compound, ((Y + Z) / (X + Y + Z))×100 [%] is 40 [%] or more and 100 [%] or less. The quantum dot dispersion liquid according to any one of claims 13 to 19.

26. The quantum dot dispersion according to any one of claims 13 to 25, wherein the dialkoxysilane compound is any one of 3-(2-Aminoethylamino)propyl dimethoxy methyl silane, 3-Aminopropyl dimethoxy methyl silane, 3-Aminopropyl diethoxy methyl silane, and 3-Mercaptopropyl (dimethoxy) methyl silane.

27. The quantum dot dispersion according to any one of claims 13 to 26, wherein the trialkoxysilane compound is any one of 3-(2-Aminoethylamino)propyl trimethoxy silane, [3-(6-Aminohexylamino)propyl] trimethoxy silane, 3-(2-Aminoethylamino)propyl triethoxy silane, (3-Mercaptopropyl) triethoxy silane, 3-Aminopropyl trimethoxy silane, 1-[3-(Trimethoxysilyl)propyl] urea, and 1-[3-(Triethoxysilyl)propyl] urea.

28. The quantum dot dispersion according to any one of claims 13 to 27, comprising a monoalkoxysilane compound or a monoalkoxysilane derivative as a capping agent.

29. When the dialkoxysilane compound is contained in an amount of Y moles, the trialkoxysilane compound is contained in an amount of Z moles, and the monoalkoxysilane compound is contained in an amount of A moles, the quantum dot dispersion according to claim 28, wherein ((A / (Y + Z + A)) × 100 [%]) is 30 [%] or more and 70 [%] or less.

30. The quantum dot dispersion according to claim 29, wherein ((A / (Y + Z + A)) × 100 [%]) is 30 [%] or more and less than 50 [%].

31. The quantum dot dispersion according to claim 29, wherein ((A / (Y + Z + A)) × 100 [%]) is 50 [%] or more and 70 [%] or less.

32. The quantum dot dispersion according to any one of claims 28 to 31, wherein the monoalkoxysilane compound contains one alkoxy group and three non-reactive groups.

33. The quantum dot dispersion liquid according to claim 32, wherein the alkoxy group of the monoalkoxysilane compound is selected from a methoxy group, an ethoxy group, a propoxy group, and a butoxy group.

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