Semiconductor nanoparticle composite, semiconductor nanoparticle composite dispersion, semiconductor nanoparticle composite composition, and semiconductor nanoparticle composite cured film

Abstract

To provide a semiconductor nanoparticle complex that is dispersible at a high mass fraction in a polar dispersion medium while maintaining high fluorescence quantum yield (QY) in semiconductor nanoparticles.SOLUTION: Provided is a semiconductor nanoparticle complex in which a ligand is coordinated to a surface of a semiconductor nanoparticle. The semiconductor nanoparticle is a core-shell type semiconductor nanoparticle including a core containing In and P and one or more layers of shells. The semiconductor nanoparticle further includes halogen and the molar ratio of halogen to In is 0.80 to 15.00 in terms of atoms. The ligand includes one or more mercapto fatty acid esters represented by the following general formula: HS-R1-COO-R2 (1). The mercapto fatty acid ester has an SP value of 9.20 or more. The mercapto fatty acid ester has a molecular weight of 700 or less, and the average SP value of the entire ligand is 9.10 to 11.00.SELECTED DRAWING: None

Description

[Technical Field]

[0001] The present invention relates to semiconductor nanoparticle composites. [Background technology]

[0002] Semiconductor nanoparticles (quantum dots, QDs) are so small that quantum confinement effects are manifested. The band gap is dependent on the semiconductor nanoparticles. The excitons formed in the nuclei recombine to emit photons with energy according to the band gap. Therefore, by appropriately selecting the composition and particle size of semiconductor nanoparticles, it is possible to obtain a desired wavelength. can be obtained.

[0003] In the early stages of research into semiconductor nanoparticles, elements including Cd and Pb were mainly investigated. Since Cd and Pb are substances subject to restrictions such as the restriction on the use of specific hazardous substances, in recent years, non-Cd Pb-based and non-Pb-based semiconductor nanoparticles have been studied.

[0004] Semiconductor nanoparticles have a wide range of applications, including displays, biolabeling, and solar cells. For display applications, QD films and QD patterning are being attempted. It is expected to be applied to self-luminous devices (QLEDs) and other applications.

[0005] Figure 2 shows the outline of the device configuration for converting the wavelength from a light source in a conventional display. As shown in Figure 2, a blue LED 101 is used as the light source. Blue light is converted into white light. The conversion from blue light to white light requires the use of semiconductors. A QD film is made by dispersing nanoparticles in a resin and forming it into a film with a thickness of about 100 μm. A wavelength conversion layer such as the QD film 102 is preferably used. The obtained white light is further filtered through a color filter (R) 104 and a color filter (G) 10 5, and color filter (B) 106 respectively provide red light, green light, and blue light. The polarizing plate is omitted in Figure 2.

[0006] Recently, as shown in Figure 1, QD patterning has been used as a wavelength conversion layer without using a QD film. The development of a display using this type of polarizer (polarizer not shown) is currently underway. In this type of display, the blue light from the blue LED1 light source is not converted into white light, Direct blue-to-red or blue-to-green light generation using QD patterning (7, 8) QD patterning (7, 8) involves the patterning of semiconductor nanoparticles dispersed in a resin. The thickness is limited to 5 μm to 10 μm due to the structural limitations of the display. As for blue, the blue light from the blue LED 1, which is the light source, is diffused. The light is passed through a diffusion layer 9 containing an agent. [Prior art documents] [Patent documents]

[0007] [Patent Document 1] Japanese Patent Application Laid-Open No. 2013-136498 [Non-patent literature]

[0008] [Non-Patent Document 1] Takashi Jin, "Semiconductor Quantum Dots, Their Synthesis and Applications in Life Sciences," Production and Technology, Vol. 63, No. 2, pp. 58-63, 2011 [Non-patent document 2] Fabien Dubois et al, “A Versatile Strategy for Quantum Dot Ligand Exchange” J.AM.CHEM.SOC Vol.129, No.3, p.482-483, 2007 [Non-patent document 3] Boon-Kin Pong et al, “Modified Ligand-Exchange for Efficient Solubilization of CdSe / ZnS Quantum Dots in Water: A Procedure Guided by Computational Studies” Langmuir Vol.24, No.10, p.5270-5276, 2008 [Non-patent document 4] Samsulida Abd. Rahman et al, “Thiolate-Capped CdSe / ZnS Core-Shell Quantum Dots for the Sensitive Detection of Glucose” Sensors Vol.17, No.7, p.1537, 2017 [Non-Patent Document 5] Whitney Nowak Wenger et al, “Functionalization of Cadmium Selenide Quantum Dots with Poly(ethylene glycol): Ligand Exchange, Surface Coverage, and Dispersion Stability” Langmuir, Vol.33, No.33, pp8239-8245, 2017 Summary of the Invention [Problem to be solved by the invention]

[0009] Semiconductor nanoparticles and semiconductor nanoparticle composites are generally dispersed in a dispersion medium to form a dispersion liquid. In particular, for display applications, glycol ethers are used. Dispersion in polar organic dispersion medium such as esters and glycol ether esters By using and curing the dispersion, QD films and QD patterning can be performed. Then, in order to increase the wavelength conversion efficiency, the semiconductor nanoparticles in the cured film are A high mass fraction of particles is desired.

[0010] However, semiconductor nanoparticles and semiconductor nanoparticle composites synthesized in non-polar dispersion media Because of its high hydrophobicity, it is easy to disperse in non-polar dispersion media, but difficult to disperse in polar dispersion media. It was.

[0011] Semiconductor nanoparticles and semiconductor nanoparticle composites synthesized in non-polar dispersion media exhibit dipole-dipole interactions. Therefore, it is difficult to dissolve in organic solvents, even among polar dispersion media. Like the semiconductor nanoparticles formed, toluene and chloroform, which have small dipole-dipole forces and hydrogen bonding forces, However, these polar dispersion media are highly toxic. Therefore, it is not practical.

[0012] Ligand exchange is a known method for making semiconductor nanoparticles dispersible in polar dispersion media. The ligand exchange method is a method for bonding a ligand to the surface of semiconductor nanoparticles. This method involves replacing the ligand contained in the nanoparticle complex with a ligand having a hydrophilic group. The semiconductor nanoparticle composite thus obtained can be dispersed in a polar dispersion medium. However, the semiconductor nanoparticles disclosed in Non-Patent Documents 1 to 5 and Patent Document 1 Although particle composites enable semiconductor nanoparticles to be dispersed in polar dispersion media, the luminescence efficiency decreases. There was a problem.

[0013] Another method for making semiconductor nanoparticles dispersible in polar dispersion media is encapsulation. The encapsulation method is a method of bonding a ligand to the surface of semiconductor nanoparticles. Since this method involves further coating the semiconductor nanoparticle composite with an amphiphilic polymer, The amount of dispersant relative to the nanoparticles increases, making it difficult to achieve a high mass fraction of semiconductor nanoparticles. This makes it difficult to apply.

[0014] For this reason, semiconductor nanoparticle composites have the advantage of high fluorescence quantum efficiency of semiconductor nanoparticles. There is a demand for a material that can be dispersed at a high mass fraction in a polar dispersion medium while maintaining its QY. There are.

[0015] In addition, when forming a cured film such as a QD film or QD patterning, the dispersion Any curing method can be used to cure the resin. However, if the curing method is thermal curing, In the case of the semiconductor nanoparticle composite, heat is applied to the dispersion liquid, and the semiconductor nanoparticles and the semiconductor nanoparticles are heated. The composite is required to be heat resistant.

[0016] In addition, when forming a cured film such as a QD film or QD patterning, the dispersion Although any curing method can be used to cure the resin, some curing methods (e.g., For ink jet applications, etc., the dispersion may be required to have a low viscosity.

[0017] Therefore, an object of the present invention is to provide a method for producing semiconductor nanoparticles with high fluorescence quantum efficiency (QY) while maintaining the high fluorescence quantum efficiency (QY). To provide a semiconductor nanoparticle composite that can be dispersed at a high mass fraction in a polar dispersion medium. Another object of the present invention is to provide a method for producing semiconductor nanoparticles with high fluorescence quantum efficiency (QY) while maintaining the high fluorescence quantum efficiency (QY). In addition to being able to disperse at a high mass fraction in polar dispersion media, it has high heat resistance and is suitable for applications where heat resistance is required. The present invention also aims to provide a semiconductor nanoparticle composite that is useful in desired applications. The purpose of this study is to develop a polar dispersion of semiconductor nanoparticles while maintaining the high fluorescence quantum efficiency (QY). In addition to being able to disperse in a medium at a high mass fraction, the viscosity of the dispersion when dispersed in the dispersion medium is low. and to provide a semiconductor nanoparticle composite that is useful in applications where low viscosity of the dispersion is required. The reason is that. [Means for solving the problem]

[0018] The above problems are solved by the present invention described below. That is, the semiconductor nanoparticle composite (1) of the present invention has a structure in which ligands are attached to the surface of semiconductor nanoparticles. a semiconductor nanoparticle composite in which a tetradecane is coordinated, The semiconductor nanoparticles have a core containing In and P and one or more shell layers. Core / shell semiconductor nanoparticles, The semiconductor nanoparticles further contain a halogen, and the atomic substitution in the semiconductor nanoparticles In calculation, the molar ratio of halogen to In is 0.80 to 15.00, The ligand has the following general formula (1): HS-R1-COO-R2(1) (In general formula (1), R1 represents an alkylene group having 1 to 3 carbon atoms, and R2 represents a hydrophilic group.) Contains one or more mercapto fatty acid esters represented by The SP value of the mercapto fatty acid ester is 9.20 or more, and the mercapto fatty acid The molecular weight of the ester is 700 or less, and the average SP value of the entire ligand is 9.10 to 11.00; The present invention provides a semiconductor nanoparticle composite characterized by the above.

[0019] The present invention (2) also provides a mercapto fatty acid ester molecule represented by the general formula (1): The semiconductor nanoparticle composite according to (1) is characterized in that the amount of hydroxyl groups is 300 or more and 700 or less. This is what we do.

[0020] The present invention (3) also provides a mercapto fatty acid ester molecule represented by the general formula (1): The semiconductor nanoparticle composite according to (1) is characterized in that the amount of hydroxyl groups is 300 or more and 600 or less. This is what we do.

[0021] In addition, the present invention (4) is characterized in that the mass ratio of the ligand to the semiconductor nanoparticles (ligand / semiconductor nanoparticles) The semiconductor nanoparticle composite according to (2) or (3), characterized in that the particle size (particle size) is 1.00 or less. It provides the body.

[0022] In addition, the present invention (5) is characterized in that the mass ratio of the ligand to the semiconductor nanoparticles (ligand / semiconductor nanoparticles) The semiconductor nanoparticle composite according to (2) or (3), characterized in that the particle size (particle size) is 0.70 or less. It provides the body.

[0023] In addition, the present invention (6) is characterized in that the mass ratio of the ligand to the semiconductor nanoparticles (ligand / semiconductor nanoparticles) Any one of (2) to (5) semiconductor nanoparticles, characterized in that the ratio of nanoparticles to nanoparticles is 0.40 or more. It provides a child complex.

[0024] The present invention (7) also provides a method for producing a mercapto fatty acid ester molecule represented by the general formula (1): The semiconductor nanoparticle composite according to (1) is characterized in that the amount of the nanoparticles is less than 300. be.

[0025] In addition, the present invention (8) is a method for manufacturing a semiconductor nanoparticle by controlling the mass ratio of the ligand to the semiconductor nanoparticle (ligand / semiconductor nanoparticle). (7) provides a semiconductor nanoparticle composite characterized in that the particle size distribution (particle size) is 0.40 or less. This is what is done.

[0026] The present invention (9) also provides a method for producing a mercapto group represented by the general formula (1) which is contained in the entire ligand. (1) to (8) characterized in that the content of butadiene fatty acid ester is 40 mol% or more The present invention provides any one of the semiconductor nanoparticle composites.

[0027] The present invention (10) also provides a method for producing a mercapto group represented by the general formula (1) that accounts for a large proportion of the ligand as a whole. (1) to (8) characterized in that the content of caprylic fatty acid ester is 50 mol% or more ) a semiconductor nanoparticle composite.

[0028] The present invention (11) also provides a method for producing a mercapto group represented by the general formula (1) which is contained in the entire ligand. (1) to (8) characterized in that the content of caprylic fatty acid ester is 60 mol% or more ) a semiconductor nanoparticle composite.

[0029] In addition, the present invention (12) is characterized in that at least one of the shells is formed of ZnSe. The present invention provides a semiconductor nanoparticle composite according to any one of (1) to (11), characterized by: .

[0030] In addition, the present invention (13) is characterized in that the shell has two or more layers, and the outermost layer of the shell is ZnS. A semiconductor nanoparticle composite according to any one of (1) to (12), characterized in that it is formed by It is what we provide.

[0031] The present invention (14) also provides a method for manufacturing a semiconductor device comprising the steps of: a first shell covering the outer surface of the first shell, the second shell being made of ZnS; and a shell. This provides:

[0032] The present invention (15) also provides a compound in which R2 in the general formula (1) is an oligoethylene glycol group, It is any one selected from the group consisting of a polyethylene glycol group and an alkoxy group. The present invention provides a semiconductor nanoparticle composite according to any one of (1) to (14), characterized in that:

[0033] The present invention (16) also provides a terminal group that is not bonded to the carboxyl group of R2 in the general formula (1). The terminal group is any one selected from the group consisting of an alkyl group, an alkenyl group, and an alkynyl group. The present invention provides a semiconductor nanoparticle composite according to any one of (1) to (15), characterized in that is.

[0034] Furthermore, the present invention (17) is characterized in that the ligand further includes an aliphatic ligand. The present invention provides a semiconductor nanoparticle composite according to any one of (1) to (16).

[0035] In addition, the present invention (18) is characterized in that the aliphatic ligand is an aliphatic thiol, an aliphatic carboxylic acid, or the like. and aliphatic phosphines (17). The present invention provides a semiconductor nanoparticle composite.

[0036] In addition, the present invention (19) is characterized in that the quantum efficiency of the semiconductor nanoparticle composite after purification is 80% or more. The present invention provides a semiconductor nanoparticle composite according to any one of (1) to (18), characterized in that That is why.

[0037] In addition, the present invention (20) is a semiconductor nanoparticle composite having an emission spectrum half width of 38 The present invention provides a semiconductor nanoparticle composite according to any one of (1) to (19), characterized in that the nanoparticle size is 0.05 nm or less. It is intended to provide.

[0038] The present invention (21) also provides a semiconductor nanoparticle composite according to any one of (1) to (20), The present invention provides a dispersion liquid of semiconductor nanoparticle composites dispersed in a dispersion medium.

[0039] The present invention (22) also provides a semiconductor nanoparticle composite according to any one of (1) to (20), The present invention provides a semiconductor nanoparticle composite composition dispersed in a polymer or prepolymer.

[0040] The present invention (23) also provides a semiconductor nanoparticle composite (1) to (20) having a high molecular weight. The present invention provides a cured film of semiconductor nanoparticle composites dispersed in a polymer matrix.

[0041] The present invention (24) also provides a polymer having a core containing In and P and one or more shell layers. These are core / shell semiconductor nanoparticles containing halogen, which has a ratio of In to In on an atomic basis. The molar ratio of the halogen to the semiconductor nanoparticles is 0.80 to 15.00. The surface modification compound having a binding group capable of binding to the nanoparticles is contacted with the surface modification compound. a semiconductor nanoparticle composite, The surface modifying compound is represented by the following general formula (1): HS-R1-COO-R2(1) (In general formula (1), R1 represents an alkylene group having 1 to 3 carbon atoms, and R2 represents a hydrophilic group.) Contains one or more mercapto fatty acid esters represented by The SP value of the mercapto fatty acid ester is 9.20 or more, and the mercapto fatty acid The molecular weight of the ester is 700 or less, and the average SP value of the entire surface modifying compound is 9.10 to 11.00; The present invention provides a semiconductor nanoparticle composite characterized by the above.

[0042] In addition, the present invention (25) is characterized in that the surface modifying compound is bonded to one end of the semiconductor nanoparticle. The surface modification compound further includes an aliphatic group-containing surface modifying compound having an aliphatic group at one end and a bonding group at the other end. The present invention provides a semiconductor nanoparticle composite (24) characterized by the above.

[0043] In this application, the range indicated by "to" is a range that includes the numbers on both ends of the range. [Effects of the Invention]

[0044] According to the present invention, it is possible to obtain polar semiconductor nanoparticles while maintaining their high fluorescence quantum efficiency (QY). It is possible to provide a semiconductor nanoparticle composite that can be dispersed at a high mass fraction in a dispersion medium. Furthermore, according to the present invention, the polarity of semiconductor nanoparticles can be improved while maintaining a high fluorescence quantum efficiency (QY). In addition to being able to disperse at a high mass fraction in a dispersion medium with high heat resistance, In addition, the present invention can provide a semiconductor nanoparticle composite that is useful in the above-mentioned applications. By doing so, it is possible to disperse semiconductor nanoparticles in polar dispersion media while maintaining their high fluorescence quantum efficiency (QY). In addition to being dispersible at a high mass fraction, the viscosity of the dispersion when dispersed in a dispersion medium is low, To provide a semiconductor nanoparticle composite useful for applications requiring a low viscosity of the dispersion can be done. [Brief explanation of the drawings]

[0045] [Figure 1] FIG. 1 is a schematic diagram showing a QD device. [Figure 2] FIG. 1 is a schematic diagram showing a QD device. DETAILED DESCRIPTION OF THE INVENTION

[0046] (Semiconductor nanoparticle composite) The semiconductor nanoparticle composite (A) of the present invention is a semiconductor nanoparticle having a ligand coordinated to the surface thereof. A semiconductor nanoparticle composite comprising: The semiconductor nanoparticles have a core containing In and P and one or more shell layers. Core / shell semiconductor nanoparticles, The semiconductor nanoparticles further contain a halogen, and The molar ratio of halogen to the halogen atom is 0.80 to 15.00, The ligand has the following general formula (1): HS-R1-COO-R2(1) (In general formula (1), R1 represents an alkylene group having 1 to 3 carbon atoms, and R2 represents a hydrophilic group.) Contains one or more mercapto fatty acid esters represented by The SP value of the mercapto fatty acid ester is 9.20 or more, and the mercapto fatty acid The molecular weight of the ester is 700 or less, and the average SP value of the entire ligand is 9.10 to 11.00; The semiconductor nanoparticle composite is characterized by:

[0047] The semiconductor nanoparticle composite of the present invention is a semiconductor nanoparticle composite in which a ligand is coordinated to the surface of the semiconductor nanoparticle. The semiconductor nanoparticle composite of the present invention is a composite of a semiconductor nanoparticle and a ligand. It is obtained by contacting a molecule with a ligand.

[0048] In the present invention, the semiconductor nanoparticle composite is a semiconductor nanoparticle composite having luminescent properties. The semiconductor nanoparticle composite of the present invention absorbs and emits light in the range of 340 nm to 480 nm. These particles emit light with a peak wavelength of 400 nm to 750 nm.

[0049] The full width at half maximum (FWHM) of the emission spectrum of the semiconductor nanoparticle composite of the present invention is 38 nm or less. It is preferable that the wavelength of the light emitted from the source is 35 nm or less, and more preferably 35 nm or less. When the half width is in the above range, the semiconductor nanoparticle composite can be applied to a display or the like. Color mixing can be reduced.

[0050] The semiconductor nanoparticle composite of the present invention preferably has a fluorescence quantum efficiency (QY) of 80% or more. It is preferable that the fluorescence quantum efficiency of the semiconductor nanoparticle composite is 8% or more, and more preferably 85% or more. 0% or more, more efficient color conversion can be achieved when semiconductor nanoparticles are used in applications. .

[0051] In the present invention, the optical properties of the semiconductor nanoparticle composite are measured using a quantum efficiency measurement system. The semiconductor nanoparticle composite is dispersed in a dispersion liquid, and the emission spectrum is measured by applying excitation light. From the emission spectrum obtained here, the amount of re-excited fluorescence is calculated. Fluorescence quantum efficiency (QY) is calculated from the emission spectrum after re-excitation correction, excluding the induced fluorescence emission spectrum. The dispersion liquid is, for example, normal hexane, PGMEA, chloroform, etc. Roholm, etc.

[0052] (semiconductor nanoparticles) The semiconductor nanoparticles constituting the semiconductor nanoparticle composite of the present invention contain In and P. These are core / shell semiconductor nanoparticles that have a core and one or more shell layers. The particles may have at least one shell layer, and examples of semiconductor nanoparticles include: Core / shell type semiconductor nanoparticles consisting of a core and one shell layer, and core and two shell layers core / shell semiconductor nanoparticles consisting of a core and three or more shell layers; In particular, the shell consists of two or more layers, making it possible to The fluorescent quantum efficiency of the particles can be maintained, and the semiconductor nanoparticle composite also has a high fluorescent quantum efficiency. In addition, the structure of the semiconductor nanoparticles is such that the shell is Although it is sufficient if the shell covers at least a portion of the surface, a structure in which the shell covers the entire surface of the core is preferred, and a structure in which the shell uniformly covers the entire surface of the core is particularly preferred.

[0053] The shell preferably contains a shell having a composition containing Zn and Se, and the shell At least one of the semiconductor nanoparticles is preferably made of ZnSe. When the outermost layer has a shell of the above composition, it is preferable that the outermost layer is a shell of a composition containing Zn and S. It is preferable that the metal is ZnS.

[0054] In particular, the shell is formed of at least ZnSe and covers the outer surface of the core particle. The first shell and the second shell made of ZnS cover the outer surface of the first shell. In this case, the fluorescence quantum efficiency can be increased.

[0055] The composition in the shell does not necessarily have to be a stoichiometric composition as long as the effect of the present invention is not impaired. Each shell may contain elements other than Zn, Se, and S, or elements constituting the shell may be contained within the shell. The nanotube may have one or more gradient shells in which the ratio of the elements varies.

[0056] In the present invention, it is important to consider whether the shell covers at least a part of the core, and whether the shell is thick enough to cover the core. The element distribution inside the well can be measured using, for example, an energy dispersive X-ray microscope (EDX) using a transmission electron microscope. This can be confirmed by analyzing the composition using X-ray spectroscopy (TEM-EDX). .

[0057] The semiconductor nanoparticles in the semiconductor nanoparticle composite of the present invention contain a halogen. The molar ratio of halogen to In in the particles is preferably 0.80 to 15.00 in atomic terms. The halogen contained in the semiconductor nanoparticles is F, Cl, Br is preferred. When the semiconductor nanoparticles contain halogen in the above range, they have a high fluorescence quantum yield. Furthermore, during the synthesis of the semiconductor nanoparticle composite described below, The halogen atom can prevent the formation of agglomerates. The presence of the nanoparticles in the interface and / or shell of the semiconductor nanoparticles enhances the aforementioned effects. It can be done.

[0058] In the semiconductor nanoparticles of the semiconductor nanoparticle composite of the present invention, the molar ratio of P to In is The atomic ratio is preferably 0.20 to 0.95. The molar ratio is preferably 10.00 to 60.00 in terms of atoms.

[0059] The elements that make up semiconductor nanoparticles are analyzed using a high-frequency inductively coupled plasma emission spectrometer. This can be done using an inductively coupled plasma (ICP) analyzer or an X-ray fluorescence analyzer (XRF).

[0060] An example of a method for producing semiconductor nanoparticles will be disclosed below. A precursor obtained by mixing an In precursor, a P precursor, and, if necessary, an additive in a solvent. By heating the mixture, the core of the semiconductor nanoparticles can be formed. Coordinating and non-coordinating solvents are used. Examples of solvents include 1-octadecene, hexadecane, squalane, oleylamine, Examples include trioctylphosphine and trioctylphosphine oxide. Precursors of In include acetates, carboxylates, and halides containing In. These include, but are not limited to: Examples of precursors of P include, but are not limited to, organic compounds and gases containing P. When the precursor is a gas, the gas is added to a precursor mixture containing other gases. The core can be formed by reacting while injecting.

[0061] The semiconductor nanoparticles may contain one or more elements other than In and P as long as the effect of the present invention is not impaired. The core may contain more than one element, and in that case, the precursor of the element may be added during the core formation. Examples of additives include carboxylic acids, amines, thiols, and phosphite as dispersants. amines, phosphine oxides, phosphinic acids, and phosphonic acids. However, the dispersant may also serve as a solvent.

[0062] After forming the core of the semiconductor nanoparticle, a halide is added as needed to form the semiconductor nanoparticle. The luminescence properties of the nanoparticles can be improved.

[0063] In one embodiment, an In precursor and optionally a precursor containing a dispersing agent in a solvent. The solution is mixed under vacuum, heated at 100 to 300°C for 6 to 24 hours, and then Add the P precursor and heat at 200 to 400°C for 3 to 60 minutes, then cool. A fluorine precursor is added, and the temperature is increased to 25°C to 300°C, preferably 100°C to 300°C, more preferably By heat treating at 150°C to 280°C, a core particle dispersion liquid containing core particles can be obtained. can.

[0064] By adding a shell-forming precursor to the synthesized core particle dispersion, semiconductor nanoparticles are formed. The molecules adopt a core / shell structure, which can enhance the fluorescence quantum efficiency (QY) and stability. .

[0065] The elements that make up the shell form alloys, heterostructures, or amorphous structures on the surface of the core particle. However, some of the particles are thought to have moved to the interior of the core particle by diffusion. It can also be considered that...

[0066] The added shell-forming elements are mainly present near the surface of the core particle, and act to surround the semiconductor nanoparticles. The core / shell structure of semiconductor nanoparticles is characterized by the shell acting as a protective layer against environmental factors. It is preferable that the surface of the core particle is at least partially covered with the hydroxyl group, and more preferably the entire surface of the core particle. It is preferable that the surface is uniformly covered.

[0067] In one embodiment, after adding a Zn precursor and a Se precursor to the aforementioned core particle dispersion, Heat at 0°C to 300°C, preferably 180°C to 250°C, and then mix the Zn precursor and S precursor and heated at 200°C to 400°C, preferably 250°C to 350°C. Core / shell type semiconductor nanoparticles can be obtained.

[0068] Here, although not particularly limited, examples of the Zn precursor include zinc acetate and propionic acid. Zinc and carboxylates such as zinc myristate, and halogens such as zinc chloride and zinc bromide. Examples of suitable organic salts include zinc chloride, diethyl zinc, and other organic salts. The Se precursors include tributylphosphine selenide and trioctylphosphine selenide. phosphine selenides such as phosphine selenide and tris(trimethylsilyl)phosphine selenide; Selenols such as benzeneselenol and selenocysteine, and selenium / octa A decene solution or the like can be used. The S precursors include tributylphosphine sulfide and trioctylphosphine sulfide. phosphine sulfides such as sulfide and tris(trimethylsilyl)phosphine sulfide thiols such as thiols, octanethiol, dodecanethiol, and octadecanethiol and sulfur / octadecene solutions can be used.

[0069] The shell precursors may be premixed and added in one or multiple additions. The shell precursors may be added separately at once or in multiple batches. If adding the shell precursor in several separate steps, you can heat it at different temperatures after each addition. good.

[0070] In the present invention, the method for producing semiconductor nanoparticles is not particularly limited. In addition to the above-mentioned methods, Conventional methods such as hot injection, homogeneous solvent, reverse micelle, and CVD methods Any method may be used for the preparation.

[0071] (ligand) The semiconductor nanoparticle composite of the present invention is a semiconductor nanoparticle in which a ligand is coordinated to the surface of the semiconductor nanoparticle. The coordination mentioned here means that the ligands chemically affect the surface of the semiconductor nanoparticles. Coordination bonds or any other bonding modes (e.g., covalent bonds) can be attached to the surface of semiconductor nanoparticles. The semiconductor nanoparticles may be bonded by a bonding method such as an ionic bond, a hydrogen bond, or the like, or ... by a bonding method such as an ionic bond, a hydrogen bond, or the like, or by a bonding method such as an ionic bond, a hydrogen bond, or the like, or by the bonding method such as an ionic bond, a hydrogen bond, an ionic bond, an ionic bond, or the like, or by the bonding When at least a part of the molecule has a ligand, it is not necessary to form a bond. .

[0072] In the semiconductor nanoparticle composite of the present invention, the ligand coordinated to the semiconductor nanoparticle is It includes a mercapto fatty acid ester represented by general formula (1). HS-R1-COO-R2(1)

[0073] In the general formula (1), R1 represents an alkylene group having 1 to 3 carbon atoms, and R2 represents a hydrophilic group. In other words, the mercapto fatty acid ester represented by the general formula (1) has -SH bonded to one of R1. and —COO—R2 is bonded to the other end. In the above, the ligand coordinated to the semiconductor nanoparticle is a mercaptolipid represented by the general formula (1). The mercapto fatty acid ester represented by the general formula (1) may be contained. It may contain two or more types of esters.

[0074] The mercapto fatty acid ester represented by general formula (1) is coordinated to semiconductor nanoparticles, In this way, a semiconductor nanoparticle composite having a high fluorescence quantum efficiency and a narrow half-value width can be obtained.

[0075] In the general formula (1), R1 is a methylene group (-CH2-), an ethylene group (-CH2C H2-), propylene group (-CH2CH2CH2-), methylethylene group (-CH(CH 3)-), and dimethylmethylene group (-C(CH3)2-).

[0076] In the general formula (1), R2 is not particularly limited as long as it is a hydrophilic group, and examples thereof include alkyl groups, Alkynyl group, alkenyl group, alkoxy group, hydroxy group, aldehyde group, carboxy aryl group, amino group, imino group, nitro group, cyano group, vinyl group, aryl group, halogeno group, Examples of hydrophilic groups include those containing a ketone group, an ether bond, an ester bond, a siloxane bond, and the like. R2 is an oligoethylene glycol group, a polyethylene glycol group, or an alkoxy group. A hydrophilic group having a hydroxyl group is preferred, and an oligoethylene glycol group or a polyethylene glycol group is preferred. It is particularly preferred that R2 is an oligoethylene glycol group, a polyethylene glycol group, or The hydrophilic group containing alkoxy or alkoxy groups allows semiconductor nanoparticles to be easily dissolved in polar solvents. Furthermore, in the general formula (1), the carboxyl group of R2 can be dispersed in a high concentration. The terminal group not bonded to the alkyl group is a group consisting of alkyl groups, alkenyl groups and alkynyl groups. The side of R2 that is not bonded to the carboxyl group is preferably selected from the following: The terminal group is any one selected from the group consisting of an alkyl group, an alkenyl group, and an alkynyl group. This suppresses the interaction between the semiconductor nanoparticle complexes and allows the semiconductor nanoparticles to be dissolved in a polar solvent. It can be dispersed in a solvent at a high concentration.

[0077] The molecular weight of the mercapto fatty acid ester represented by general formula (1) is 700 or less. The molecular weight of the mercapto fatty acid ester represented by the general formula (1) is 700 or less, It becomes possible to disperse conductive nanoparticles in polar solvents at high concentrations.

[0078] In the present invention, the molecular weight of the mercapto fatty acid ester represented by the general formula (1) is refers to the average molecular weight of the mercapto fatty acid ester represented by general formula (1). The average molecular weight of the mercapto fatty acid ester expressed as The number average of the obtained values ​​was calculated as the average molecular weight (number average molecular weight Mn )

[0079] Furthermore, the SP value of the mercapto fatty acid ester represented by the general formula (1) is 9.20 or more. The SP value is preferably in the range of 9.20 to 12.00. It is possible to disperse particles in a polar solvent. Here, the SP value is calculated using the Y-MB method. In the present invention, two or more ligands represented by general formula (1) are used. When using mercapto fatty acid esters, the SP of each mercapto fatty acid ester is The SP value is calculated by multiplying the value by the volume fraction of each mercapto fatty acid ester and then adding them together. is the SP value of the mercapto fatty acid ester. For example, if the semiconductor nanoparticles have an SP value of A1, Mercapto fatty acid ester is P1 volume %, and mercapto fatty acid ester with SP value A2 is P2 When the mercapto fatty acid ester is coordinated as follows: It is expressed as: SP value of mercapto fatty acid ester = Σ(Ai × Pi / 100) (2)

[0080] In the semiconductor nanoparticle composite of the present invention, the ligand is a metal compound represented by general formula (1) The general formula (1) can contain ligands other than the caprylic acid fatty acid ester. As a ligand other than the mercapto fatty acid ester shown in the above, a semiconductor nanoparticle attached to one end side is There are no particular limitations on the compound as long as it has a bonding group that can be coordinated, and it can be coordinated to the semiconductor nanoparticles. The compound can be used as a compound having a mercapto fatty acid ester represented by the general formula (1). When used in combination with sterol, the average SP value of the entire ligand is 9.20 to 11.00, preferably It is fine as long as it can be adjusted between 9:20 and 10:00.

[0081] The SP value of the ligand other than the mercapto fatty acid ester represented by the general formula (1) is not particularly limited. Although not limited thereto, it is preferably 7.50 to 15.00, and particularly preferably 7.50 to 15.00. is.

[0082] The average SP value of all the ligands coordinated to the semiconductor nanoparticles is 9.20 to 11.00. The average of all the ligands coordinated to the semiconductor nanoparticles is preferably 9.20 to 10.00. When the SP value is within the above range, it becomes possible to disperse semiconductor nanoparticles in a polar solvent. The SP value of the ligand can be calculated from the structural formula using the Y-MB method. When multiple types of ligands are coordinated to the nanoparticle, the SP value of each ligand is multiplied by the volume fraction of the ligand. After multiplying by the SP value of the ligand, the average SP value of all the ligands is calculated. For example, in semiconductor nanoparticles, P1 volume % of ligands with SP value A1 and P2 volume % of ligands with SP value A2 are When P2 volume % is coordinated, the average SP value of all ligands is calculated by the following equation (3): is represented. Average SP value of all ligands = Σ(Ai × Pi / 100) (3)

[0083] As the ligand other than the mercapto fatty acid ester represented by the general formula (1), aliphatic ligands By including an aliphatic ligand as the ligand, the semiconductor nanoparticles can be made extremely It can be dispersed at high concentrations in organic solvents with a wider range of SP values. Furthermore, when applied to the composition and dispersion liquid described later, the This allows for a wider range of options.

[0084] Aliphatic ligands include aliphatic thiols, aliphatic carboxylic acids, aliphatic phosphines, and Aliphatic phosphine oxides and aliphatic amines are examples of these, and they have strong coordination power with semiconductor nanoparticles. Therefore, the compound is selected from the group consisting of an aliphatic thiol, an aliphatic carboxylic acid, and an aliphatic phosphine. It is preferable to use one or more of these. The aliphatic group of the aliphatic ligand may contain a substituent or a heteroatom. Good too.

[0085] The content of the mercapto fatty acid ester represented by the general formula (1) in the entire ligand is It is preferably 40 mol % or more, more preferably 50 mol % or more, and even more preferably The proportion of mercaptans represented by general formula (1) in the total ligands is 60 mol % or more. By setting the content of the fatty acid ester in the above range, it is possible to form semiconductor nanoparticles in a polar solvent at a high concentration. This allows for high dispersion and improved quantum efficiency.

[0086] The semiconductor nanoparticle composite (A) of the present invention may be of the following first embodiment: The first embodiment of the semiconductor nanoparticle composite (A) of the present invention is The molecular weight of the mercapto fatty acid ester represented by the general formula (1) is 300 or more and 700 or less. The semiconductor nanoparticle composite has a molecular weight of 300 or more and preferably 600 or less.

[0087] That is, the first embodiment of the semiconductor nanoparticle composite (A) of the present invention is a semiconductor nanoparticle having a surface a semiconductor nanoparticle complex having a ligand coordinated thereto, The semiconductor nanoparticles have a core containing In and P and one or more shell layers. Core / shell semiconductor nanoparticles, The semiconductor nanoparticles further contain a halogen, and the atomic substitution in the semiconductor nanoparticles In calculation, the molar ratio of halogen to In is 0.80 to 15.00, The ligand has the following general formula (1): HS-R1-COO-R2(1) (In general formula (1), R1 represents an alkylene group having 1 to 3 carbon atoms, and R2 represents a hydrophilic group.) Contains one or more mercapto fatty acid esters represented by The SP value of the mercapto fatty acid ester is 9.20 or more, and the mercapto fatty acid The molecular weight of the ester is 300 or more and 700 or less, preferably 300 or more and 600 or less, and the average SP value of the entire ligand is 9.10 to 11.00; The semiconductor nanoparticle composite is characterized by the following: When the molecular weight of the ester is within the above range, the semiconductor nanoparticles are dispersed in the organic solvent. This ensures sufficient steric hindrance, making it possible to disperse at higher concentrations, and furthermore, In the present invention, the heat resistance of the semiconductor nanoparticle composite is improved. When the particle composite is heat-treated at a certain temperature, the particles are redispersed in the solvent in which they were dispersed before the heat treatment. It means that it is distributable.

[0088] As one embodiment of the heat resistance evaluation, the semiconductor nanoparticle composite was heated at 180 After treating at ℃ for 1 hour, judge whether or not the semiconductor nanoparticle composite can be redispersed in a good solvent. Semiconductor nanoparticle composites that do not have sufficient heat resistance may be subject to heat treatment due to denaturation or desorption of the ligands. Dispersibility in a good solvent after heating is significantly reduced.

[0089] In the first embodiment of the semiconductor nanoparticle composite (A) of the present invention, the quality of the ligand and the semiconductor nanoparticles is The ratio (ligand / semiconductor nanoparticles) is preferably 1.00 or less, and more preferably 0.70 or less. The mass ratio of the ligand to the semiconductor nanoparticles (ligand / semiconductor) is preferably less than 10 ... By keeping the content of nanoparticles within the above range, the heat resistance of the semiconductor nanoparticle composite can be maintained. This makes it possible to disperse semiconductor nanoparticles in polar solvents at high concentrations.

[0090] In the first embodiment of the semiconductor nanoparticle composite (A) of the present invention, the ligand and the semiconductor nanoparticle are It is preferable that the mass ratio of the ligand to the semiconductor nanoparticles is 0.40 or more. The mass ratio of the ligand to the semiconductor nanoparticles (ligand / semiconductor nanoparticles) is within the above range. This allows the semiconductor nanoparticles to be concentrated in a polar solvent while maintaining the heat resistance of the semiconductor nanoparticle composite. It is possible to distribute it in this way.

[0091] The semiconductor nanoparticle composite (A) of the present invention may be of the following second form: The second embodiment of the semiconductor nanoparticle composite (A) of the present invention is That is, the molecular weight of the mercapto fatty acid ester represented by the general formula (1) is less than 300. Conductor nanoparticle composite.

[0092] That is, the second form of the semiconductor nanoparticle composite (A) of the present invention is a semiconductor nanoparticle having a surface a semiconductor nanoparticle complex having a ligand coordinated thereto, The semiconductor nanoparticles have a core containing In and P and one or more shell layers. Core / shell semiconductor nanoparticles, The semiconductor nanoparticles further contain a halogen, and the atomic substitution in the semiconductor nanoparticles In calculation, the molar ratio of halogen to In is 0.80 to 15.00, The ligand has the following general formula (1): HS-R1-COO-R2(1) (In general formula (1), R1 represents an alkylene group having 1 to 3 carbon atoms, and R2 represents a hydrophilic group.) Contains one or more mercapto fatty acid esters represented by The SP value of the mercapto fatty acid ester is 9.20 or more, and the mercapto fatty acid the molecular weight of the ester is less than 300, preferably 100 or more and less than 300; and the average SP value of the entire ligand is 9.10 to 11.00; The semiconductor nanoparticle composite is characterized by the following: When the molecular weight of the ester is within the above range, the semiconductor nanoparticle composite can be dispersed at a high mass fraction. In the present invention, the viscosity of the dispersion can be reduced even if the semiconductor nanoparticle complex is The viscosity of the dispersion when the composite is dispersed at a high mass fraction is low when the semiconductor nanoparticle composite is The semiconductor nanoparticles were dispersed in isobornyl acrylate so that the mass ratio of the semiconductor nanoparticles was 30.0 mass%. This means that when dispersed, the viscosity at 25°C is 30 cp or less.

[0093] In the second embodiment of the semiconductor nanoparticle composite (A) of the present invention, the quality of the ligand and the semiconductor nanoparticles is The ratio (ligand / semiconductor nanoparticles) is preferably 0.40 or less. When the mass ratio of the semiconductor nanoparticles (ligand / semiconductor nanoparticles) is within the above range, The semiconductor nanoparticles are dispersed in a dispersion liquid while suppressing an increase in viscosity of the dispersion liquid in which the semiconductor nanoparticle composite is dispersed. It is possible to disperse it in polar solvents at high concentrations.

[0094] The semiconductor nanoparticle composite (B) of the present invention comprises a core containing In and P and one or more layers of nanoparticles. and a core / shell type semiconductor nanoparticle having a shell and further containing halogen, In calculations, the molar ratio of halogen to In was 0.80 to 15.00. contacting one end of the semiconductor nanoparticle with a surface modifying compound having a bonding group capable of bonding to the semiconductor nanoparticle; A semiconductor nanoparticle composite obtained by The surface modifying compound is represented by the following general formula (1): HS-R1-COO-R2(1) (In general formula (1), R1 represents an alkylene group having 1 to 3 carbon atoms, and R2 represents a hydrophilic group.) Contains one or more mercapto fatty acid esters represented by The SP value of the mercapto fatty acid ester is 9.20 or more, and the mercapto fatty acid The molecular weight of the ester is 700 or less, and the average SP value of the entire surface modifying compound is 9.10 to 11.00; The semiconductor nanoparticle composite is characterized by:

[0095] The semiconductor nanoparticle composite (B) of the present invention is a semiconductor nanoparticle having a semiconductor nanoparticle at one end. A semiconductor nanoparticle obtained by contacting a surface modifying compound having a bonding group that bonds to the surface of the semiconductor nanoparticle. The method for contacting the semiconductor nanoparticles with the surface modifying compound is not particularly limited. Although it is not yet known, one method is to add a surface modifying compound to a dispersion of semiconductor nanoparticles. Depending on the bonding strength of the surface modifying compound to the semiconductor nanoparticles, The addition may be accompanied by heating or stirring.

[0096] The semiconductor nanoparticles according to the semiconductor nanoparticle composite (B) of the present invention are The same applies to the semiconductor nanoparticles related to the subcomposite (A).

[0097] Binding group related to a surface modifying compound having a binding group at one end thereof that binds to semiconductor nanoparticles Examples include thiol groups, carboxylic acid groups, phosphine groups, phosphine oxide groups, and amine groups. Examples of surface modifying compounds having a group at one end capable of binding to semiconductor nanoparticles include: Examples of the ligands include those related to the semiconductor nanoparticle composite (A) of the present invention.

[0098] In the semiconductor nanoparticle composite (B) of the present invention, the bonding property of the semiconductor nanoparticles is bonded to one end of the semiconductor nanoparticles. As a surface modifying compound having a group, a mercapto fatty acid ester represented by the following general formula (1) Including Tell. HS-R1-COO-R2(1)

[0099] In the semiconductor nanoparticle composite (B) of the present invention, the surface modifying compound represented by general formula (1) The mercapto fatty acid ester represented by the following formula (1) is a mercapto fatty acid ester in the semiconductor nanoparticle composite (A) of the present invention. It is the same as the mercapto fatty acid ester represented by the general formula (1).

[0100] In the semiconductor nanoparticle composite (B) of the present invention, the mercapto lipid represented by general formula (1) By using fatty acid esters as surface modifying compounds, the fluorescence quantum efficiency is high and the half-value Narrow semiconductor nanoparticle composites can be obtained.

[0101] In the semiconductor nanoparticle composite (B) of the present invention, the mercapto lipid represented by general formula (1) The molecular weight of the fatty acid ester is 700 or less. The molecular weight of the ester is 700 or less, which allows semiconductor nanoparticles to be dispersed in polar solvents at high concentrations. It is possible to do this.

[0102] In the semiconductor nanoparticle composite (B) of the present invention, a mer represented by general formula (1) The SP value of the caprylic fatty acid ester is 9.20 or more, preferably 9.20 to 12.00. When the SP value is within the above range, the semiconductor nanoparticles can be dispersed in a polar solvent. It becomes Noh.

[0103] In the semiconductor nanoparticle composite (B) of the present invention, the bond to one end of the semiconductor nanoparticle is As a surface modifying compound having a synthetic group, a mercapto fatty acid ester represented by general formula (1) The metal compound represented by the general formula (1) may contain a surface modifying compound other than the metal compound. As a surface modification compound other than the hydroxycapto fatty acid ester, a compound bonded to one end of semiconductor nanoparticles is used. There are no particular limitations on the compound as long as it has a bonding group that bonds to the surface of the semiconductor nanoparticles. A mercapto fatty acid that can be used as a modifying compound and is represented by the general formula (1) When used in combination with esters, the average SP value of all surface modification compounds is 9.20 to 11.00. Preferably, it is possible to adjust the temperature to 9.20 to 10.00.

[0104] The SP value of the surface modifying compound other than the mercapto fatty acid ester represented by the general formula (1) is Although not particularly limited, it is preferably 7.00 to 15.00, particularly preferably 7.50 to 1 It's 5.00.

[0105] The average S of all surface modification compounds that have a bonding group on one end that binds to semiconductor nanoparticles The P value is 9.20 to 11.00, preferably 9.20 to 10.00. The average SP value of all surface modifying compounds having binding groups that bind to the body nanoparticles is within the above range. This allows the semiconductor nanoparticles to be dispersed in a polar solvent.

[0106] Examples of surface modifying compounds other than the mercapto fatty acid ester represented by general formula (1) include: an aliphatic group having a bonding group that bonds to a semiconductor nanoparticle at one end and an aliphatic group at the other end As the surface modifying compound, an aliphatic group-containing surface modifying compound is preferred. By including the compound, the semiconductor nanoparticles can be dispersed in a polar solvent at a high concentration. Furthermore, it is possible to disperse the composition in organic solvents with a wider range of SP values. Furthermore, when applied to dispersions, it becomes possible to broaden the options for dispersion media.

[0107] The aliphatic group-containing surface modifying compound includes aliphatic thiols, aliphatic carboxylic acids, aliphatic Examples include phosphine, aliphatic phosphine oxide, and aliphatic amine. Due to the strong coordination power with aliphatic thiols, aliphatic carboxylic acids, and aliphatic phosphines, The aliphatic group of the aliphatic group-containing surface modifying compound is preferably one or more selected from the group consisting of , and may contain substituents and heteroatoms.

[0108] A portion of the entire surface modifying compound having a bonding group at one end that bonds to semiconductor nanoparticles The content of the mercapto fatty acid ester represented by the general formula (1) is 40 mol % or more. It is more preferable that the content is 50 mol % or more, and even more preferable that the content is 60 mol % or more. The proportion of all surface modifying compounds having a bonding group on one end that bonds to semiconductor nanoparticles is By setting the content of the mercapto fatty acid ester represented by the general formula (1) in the above range, Semiconductor nanoparticles can be dispersed in polar solvents at high concentrations and quantum efficiency can be increased.

[0109] The semiconductor nanoparticle composite (B) of the present invention may be of the following first embodiment: The first embodiment of the semiconductor nanoparticle composite (B) of the present invention is The molecular weight of the mercapto fatty acid ester represented by the general formula (1) is 300 or more and 700 or less. The semiconductor nanoparticle composite has a molecular weight of 300 or more and preferably 600 or less.

[0110] That is, the first form of the semiconductor nanoparticle composite (B) of the present invention contains In and P. Core / shell type semiconductor nanoparticles having a core and one or more shell layers, and further comprising a halo The molar ratio of halogen to In is 0.80 to 15.00 in atomic terms. A surface modifying compound having a bonding group on one end thereof that can be bonded to the semiconductor nanoparticles is provided. a semiconductor nanoparticle composite obtained by contacting a material with another material, The surface modifying compound is represented by the following general formula (1): HS-R1-COO-R2(1) (In general formula (1), R1 represents an alkylene group having 1 to 3 carbon atoms, and R2 represents a hydrophilic group.) Contains one or more mercapto fatty acid esters represented by The SP value of the mercapto fatty acid ester is 9.20 or more, and the mercapto fatty acid the molecular weight of the ester is 300 or more and 700 or less, preferably 300 or more and 600 or less; and the average SP value of the entire surface modifying compound is 9.10 to 11.00; The semiconductor nanoparticle composite is characterized by the following: When the molecular weight of the ester is within the above range, the semiconductor nanoparticles are dispersed in the organic solvent. This ensures sufficient steric hindrance, making it possible to disperse at higher concentrations, and furthermore, The heat resistance of the nanoparticle composite is improved.

[0111] In the first embodiment of the semiconductor nanoparticle composite (B) of the present invention, a surface modifying compound and a semiconductor nanoparticle are The mass ratio of the particles (surface modifying compound / semiconductor nanoparticles) is preferably 1.00 or less. The surface modification compound and the semiconductor nanoparticles preferably have a refractive index of 0.70 or less. When the mass ratio (surface modifying compound / semiconductor nanoparticles) is within the above range, the conductive nanoparticles Dispersing semiconductor nanoparticles in a polar solvent at high concentrations while maintaining the heat resistance of the particle composite This becomes possible.

[0112] In the first embodiment of the semiconductor nanoparticle composite (B) of the present invention, a surface modifying compound and a semiconductor The mass ratio of semiconductor nanoparticles (surface modification compound / semiconductor nanoparticles) is 0.40 or more. The mass ratio of the surface modifying compound to the semiconductor nanoparticles (surface modifying compound / semiconductor nanoparticles) is preferably By the particle size being within the above range, the heat resistance of the semiconductor nanoparticle composite is maintained, It becomes possible to disperse semiconductor nanoparticles in polar solvents at high concentrations.

[0113] The semiconductor nanoparticle composite (B) of the present invention may be of the following second form: The second form of the semiconductor nanoparticle composite (B) of the present invention is That is, the molecular weight of the mercapto fatty acid ester represented by the general formula (1) is less than 300. Conductor nanoparticle composite.

[0114] That is, the second type of semiconductor nanoparticle composite (B) of the present invention contains In and P. Core / shell type semiconductor nanoparticles having a core and one or more shell layers, and further comprising a halo The molar ratio of halogen to In is 0.80 to 15.00 in atomic terms. A surface modifying compound having a bonding group on one end thereof that can be bonded to the semiconductor nanoparticles is provided. a semiconductor nanoparticle composite obtained by contacting a material with another material, The surface modifying compound is represented by the following general formula (1): HS-R1-COO-R2(1) (In general formula (1), R1 represents an alkylene group having 1 to 3 carbon atoms, and R2 represents a hydrophilic group.) Contains one or more mercapto fatty acid esters represented by The SP value of the mercapto fatty acid ester is 9.20 or more, and the mercapto fatty acid the molecular weight of the ester is less than 300, preferably 100 or more and less than 300; and the average SP value of the entire surface modifying compound is 9.10 to 11.00; The semiconductor nanoparticle composite is characterized by the following: When the molecular weight of the ester is within the above range, the dispersion liquid in which the semiconductor nanoparticle composite is dispersed can be The viscosity can be reduced.

[0115] In the second embodiment of the semiconductor nanoparticle composite (B) of the present invention, a surface modifying compound and a semiconductor nanoparticle are The mass ratio of the particles (surface modifying compound / semiconductor nanoparticles) is preferably 0.40 or less. The mass ratio of the surface modification compound to the semiconductor nanoparticles (surface modification compound / semiconductor nanoparticles) ) is within the above range, the viscosity of the dispersion in which the semiconductor nanoparticle composite is dispersed is increased. This makes it possible to disperse semiconductor nanoparticles in a polar solvent at a high concentration while suppressing the addition of the semiconductor nanoparticles.

[0116] (Regarding purification) The semiconductor nanoparticle composite of the present invention can be separated and purified from the reaction solution, if necessary. As a purification method, the semiconductor nanoparticle composite is aggregated using a poor solvent, and then the semiconductor nanoparticle composite is A method for isolating the body-nanoparticle complex is used.

[0117] In one embodiment, the semiconductor nanoparticles are dissolved by adding a polarity-reversing solvent such as acetone. The nanoparticle composite can be precipitated from the dispersion. The precipitated semiconductor nanoparticle composite can be filtered or The resulting mixture can be recovered by centrifugation or by filtration, while the remaining fraction contains unreacted starting materials and other impurities. The supernatant containing the semiconductor nanoparticle composite can be discarded or reused. The product can be washed with additional dispersant and redispersed. This purification process can be carried out, for example, by This can be repeated 2-4 times or until the desired purity is reached.

[0118] In the present invention, in addition to the above-described methods, other methods for purifying semiconductor nanoparticle composites include, for example, For example, flocculation, liquid-liquid extraction, distillation, electrodeposition, size exclusion chromatography and / or ultrafiltration. Any of these methods may be used alone or in combination.

[0119] (Semiconductor nanoparticle composite dispersion) The semiconductor nanoparticle composite of the present invention is dispersed in a polar dispersion medium. In the present invention, the semiconductor nanoparticle composite is dispersed in a dispersion medium. The state in which the semiconductor nanoparticle composite is in a state where the semiconductor nanoparticles are ... The complex does not precipitate or remain as visible turbidity (cloudiness) The semiconductor nanoparticle composite dispersed in a dispersion medium is called a semiconductor nanoparticle. This is referred to as a composite dispersion.

[0120] The semiconductor nanoparticle composite of the present invention is an organic dispersion medium having an SP value of 8.50 or more, and further an SP It disperses in organic dispersion media with an SP value of 9.00 or more and organic dispersion media with an SP value of 10.00 or more. A dispersion of the polymer nanoparticle complex is formed.

[0121] The SP value here is determined by the Hansen Solubility Parameters in the same manner as in the method for determining the SP value of the polar ligand. The Hansen solubility parameters are calculated from the Hansen solubility parameters. "Hansen Solubility Parameters: A User's Handbook”, 2nd edition, C.M. Hansen (2007), values ​​in Practice provided by Hanson and Abbot et al. This can be determined using the HSPiP program (2nd edition). For organic dispersion media not listed in the above, the content can be determined by calculation using the Y-MB method.

[0122] In the present invention, the organic dispersion medium for the semiconductor nanoparticle composite dispersion liquid of the present invention is methanol, Alcohols such as ethanol, isopropyl alcohol, and normal propyl alcohol , acetone, methyl ethyl ketone, methyl isobutyl ketone, cyclopentanone, cyclo Ketones such as hexanone, methyl acetate, ethyl acetate, isopropyl acetate, normal acetate Esters such as propyl, normal butyl acetate, and ethyl lactate, diethyl ether, dipropyl ethers such as propyl ether, dibutyl ether, and tetrahydrofuran; Ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, diethylene glycol Cholesterol monomethyl ether, ethylene glycol diethyl ether, diethylene glycol dimethyl ether, propylene glycol monomethyl ether (PGME), propylene Glycol monoethyl ether, propylene glycol monopropyl ether, propylene ethylene glycol monobutyl ether, propylene glycol dimethyl ether, dipropylene ethylene glycol dimethyl ether, propylene glycol diethyl ether, dipropylene glycol ethers such as ethylene glycol diethyl ether, ethylene glycol acetate Ethylene glycol monoethyl ether acetate, diethylene glycol monoethyl ether acetate ethyl ether acetate, diethylene glycol monobutyl ether acetate, propyl Propylene glycol monomethyl ether acetate (PGMEA), dipropylene glycol Glycol ether esters such as monoethyl ether acetate are preferred. By dispersing the semiconductor nanoparticle composite of the present invention in these organic dispersion media, the hard nanoparticles described below can be obtained. When applying it to dispersion in a synthetic film or resin, the semiconductor nanoparticle composite can be used while maintaining its dispersibility. It is possible.

[0123] In particular, in the semiconductor nanoparticle composite of the present invention, the organic dispersion medium may be an alcohol, Select polar organic dispersion media such as glycol ethers and glycol ether esters It is possible to disperse the semiconductor nanoparticle composite of the present invention in these organic dispersion media. This allows for the dispersion of semiconductor nanoparticle composites when applied to dispersion in cured films and resins, which will be described later. In particular, in the field of photoresists, PGMEA and PGME is commonly used as a diluent, and semiconductor nanoparticle composites are If the semiconductor nanoparticle complex can be dispersed in A and PGME, it will be widely used in the photoresist field. It can be widely applied.

[0124] The semiconductor nanoparticle composite of the present invention has the above-mentioned configuration, can be dispersed in an organic dispersion medium at a high mass fraction, resulting in the formation of a semiconductor nanoparticle composite particle. The mass fraction of the semiconductor nanoparticles in the dispersion is 20 mass% or more, further 30 mass% or more, Furthermore, it can be set to 35 mass % or more.

[0125] Furthermore, in the present invention, a monomer is used as a dispersion medium for the semiconductor nanoparticle composite dispersion liquid of the present invention. The monomer is not particularly limited, but may be selected from the group consisting of the following monomers, each of which is suitable for the application of semiconductor nanoparticles. A (meth)acrylic monomer is preferred as it is available in a wide range of options. Depending on the application of the semiconductor nanoparticle composite dispersion, the monomer is selected from methyl (meth)acrylate, ethylenediamine, propylene glycol, propylene glycol, propylene glycol, propylene glycol acrylate ... ethyl (meth)acrylate, propyl (meth)acrylate, butyl (meth)acrylate Isobutyl (meth)acrylate, Isoamyl (meth)acrylate, Octyl (meth)acrylate meth)acrylate, 2-ethylhexyl (meth)acrylate, dodecyl (meth)acrylate acrylate, isodecyl (meth)acrylate, lauryl (meth)acrylate, stearyl (Meth)acrylate, cyclohexyl (meth)acrylate, isobornyl (meth)acrylate Acrylate, 3,5,5-trimethylcyclohexanol (meth)acrylate, disiloxane Dicyclopentenyl (meth)acrylate, Methoxy Diethyl (meth)acrylate, Ethyl carbitol (meth)acrylate, Methoxy Polyethylene glycol acrylate, 2-ethylhexyl diglycol acrylate, Methoxypolyethyleneglycolacrylate, Methoxydipropyleneglycolacrylate acrylate, phenoxyethyl (meth)acrylate, 2-phenoxydiethylene glycol ( meth)acrylate, 2-phenoxypolyethylene glycol (meth)acrylate (n ≒2), tetrahydrofurfuryl (meth)acrylate, 2-hydroxyethyl acrylate acrylate, 2-hydroxypropyl (meth)acrylate, 4-hydroxybutyl (meth)acrylate Acrylate, 2-hydroxybutyl (meth)acrylate, dicyclopentanyloxyl Ethyl (meth)acrylate, isobornyloxylethyl (meth)acrylate, ada Manthyl (meth)acrylate, dimethyl adamantyl (meth)acrylate, dicyclo Pentenyloxyethyl (meth)acrylate, benzyl (meth)acrylate, ω-caprylic acid Carboxy-polycaprolactone (n≒2) monoacrylate, 2-hydroxy-3-phenyl Phenoxypropyl acrylate, 2-hydroxy-3-phenoxyethyl (meth)acrylate ester, (2-methyl-2-ethyl-1,3-dioxolan-4-yl)methyl(meth)ate Acrylate, (3-ethyloxetan-3-yl)methyl (meth)acrylate, o-fluoro Phenylphenol ethoxy (meth)acrylate, dimethylamino (meth)acrylate , diethylamino(meth)acrylate, 2-(meth)acryloyloxyethyl phthalate Acid, 2-(meth)acryloyloxyethylhexahydrophthalate, glycidyl (meth) Acrylate, 2-(meth)acryloyloxyethyl phosphate, acryloylmorpholine , dimethylacrylamide, dimethylaminopropylacrylamide, isopropylacrylamide acrylamide, diethylacrylamide, hydroxyethylacrylamide, and N-acrylamide From (meth)acrylic monomers such as acryloyloxyethylhexahydrophthalimide These can be used alone or in combination of two or more types. In particular, acrylic monomers can be used in a variety of applications, including Laurie, depending on the application of the semiconductor nanoparticle composite dispersion liquid. 1,6-hexadiol di(meth)acrylate and 1,6-hexadiol di(meth)acrylate It is preferable that the polyol is one or a mixture of two or more thereof.

[0126] In the present invention, a prepolymer is used as a dispersion medium for the semiconductor nanoparticle composite dispersion of the present invention. The prepolymer is not particularly limited, but an acrylic resin prepolymer can be selected. Examples of suitable resins include prepolymers, silicone resin prepolymers, and epoxy resin prepolymers.

[0127] (Semiconductor nanoparticle composite composition) In the present invention, a monomer or a polymer is used as a dispersion medium for the semiconductor nanoparticle composite dispersion of the present invention. The polymer can be selected to form a semiconductor nanoparticle composite composition. The semiconductor nanoparticle composite composition of the present invention is a semiconductor nanoparticle composite of the present invention. The present invention relates to a semiconductor nanoparticle composite composition dispersed in a prepolymer. The polymer is not particularly limited, but may be a radical polymerizable compound containing an ethylenically unsaturated bond, oxane compounds, epoxy compounds, isocyanate compounds, and phenol derivatives Examples of the monomer include the monomers used as the dispersion medium described above. In addition, the prepolymer may be the prepolymer used as the dispersion medium described above. - are some examples.

[0128] Furthermore, the semiconductor nanoparticle composite composition of the present invention can contain a crosslinking agent. Depending on the type of monomer in the semiconductor nanoparticle composite composition of the present invention, Acrylates, polyfunctional silane compounds, polyfunctional amines, polyfunctional carboxylic acids, polyfunctional thiols , polyfunctional alcohols, and polyfunctional isocyanates.

[0129] Furthermore, the semiconductor nanoparticle composite composition of the present invention can be used in a wide range of solvents, including pentane, hexane, cyclohexanone, aliphatic hydrocarbons such as hexane, isohexane, heptane, octane and petroleum ether; Coles, ketones, esters, glycol ethers, glycol ether esters aromatic hydrocarbons such as benzene, toluene, xylene and mineral spirits; and alkyl halides such as dichloromethane and chloroform, which do not affect curing. The organic solvent may further contain various organic solvents. It can be used not only for diluting the body composition but also as an organic dispersion medium. The semiconductor nanoparticle composite of the present invention is dispersed in the organic solvent, It is also possible to prepare a dispersion.

[0130] Furthermore, the semiconductor nanoparticle composite composition of the present invention is Depending on the type of polymer, appropriate initiators, scattering agents, catalysts, binders, surfactants, adhesion promoters, etc. The additives may include additives such as coloring agents, antioxidants, ultraviolet absorbers, anti-agglomerating agents, and dispersants.

[0131] Furthermore, the semiconductor nanoparticle composite composition of the present invention or the semiconductor nanoparticle of the present invention described below In order to improve the optical properties of the particle composite cured film, the semiconductor nanoparticle composite composition contains a scattering The scattering agent may be a metal oxide such as titanium oxide or zinc oxide, and these particles From the viewpoint of scattering effect, the particle diameter of the scattering agent is preferably 100 nm to 500 nm. The diameter is more preferably 200 nm to 400 nm. The luminous intensity is improved by about two times. It is preferable that the content of the compound is 2% by mass to 30% by mass of the composition, and the compound is effective in maintaining the patternability of the composition. From this viewpoint, it is more preferable that the content is 5% by mass to 20% by mass.

[0132] Due to the configuration of the semiconductor nanoparticle composite of the present invention, The mass fraction of the semiconductor nanoparticles can be 30 mass % or more. By setting the mass fraction of the semiconductor nanoparticles in the body composition to 30 mass % to 95 mass %, the following The semiconductor nanoparticle composite and the semiconductor nanoparticles can be dispersed at a high mass fraction even in the cured film. can be done.

[0133] When the semiconductor nanoparticle composite composition of the present invention is formed into a 10 μm film, the normal direction of the film The absorbance of light from the sample with a wavelength of 450 nm is preferably 1.0 or more, and more preferably 1.3 or more. It is more preferable that the ratio is 1.5 or more, and even more preferable that the ratio is 1.5 or more. Because it can efficiently absorb light from black light, it is possible to reduce the thickness of the cured film described below. The device to which it is applied can be made smaller.

[0134] (Diluted Composition) The diluted composition is the semiconductor nanoparticle composite composition of the present invention diluted with an organic solvent. This is what is done.

[0135] The organic solvent for diluting the semiconductor nanoparticle composite composition is not particularly limited, and examples thereof include For example, pentane, hexane, cyclohexane, isohexane, heptane, octane and cyclohexane. Aliphatic hydrocarbons such as oil ether, alcohols, ketones, esters, glycol ethers ethers, glycol ether esters, benzene, toluene, xylene and minerals Aromatic hydrocarbons such as dichloromethane and chloroform, and halogenated hydrocarbons such as dichloromethane and chloroform Among these, alkyl esters with solubility in a wide range of resins and coating properties are From the viewpoint of film uniformity, glycol ethers and glycol ether esters are preferred. I wish.

[0136] (Semiconductor nanoparticle composite cured film) The semiconductor nanoparticle composite cured film of the present invention is a cured film containing the semiconductor nanoparticle composite of the present invention. The semiconductor nanoparticle composite cured film of the present invention is a film that has been cured. The conductive nanoparticle composite composition or diluted composition is cured to form a film.

[0137] The semiconductor nanoparticle composite cured film of the present invention is a cured film of the semiconductor nanoparticle composite of the present invention. It contains nanoparticles, ligands coordinated to the surface of semiconductor nanoparticles, and a polymer matrix. In other words, the semiconductor nanoparticle composite cured film of the present invention is The body is a hardened film dispersed in a polymer matrix.

[0138] The polymer matrix is ​​not particularly limited, but may be (meth)acrylic resin, silicone, or the like. Resin, epoxy resin, silicone resin, maleic acid resin, butyral resin, polyester resin, melamine resin, phenolic resin, polyurethane resin, etc. The semiconductor nanoparticle composite composition of the present invention is cured to form the semiconductor nanoparticles of the present invention. The cured film of the semiconductor nanoparticle composite of the present invention may further contain a crosslinking agent. That's fine.

[0139] The method for hardening the film is not particularly limited, but may be a heat treatment, an ultraviolet treatment, or the like. The film can be cured by a curing method suitable for the material.

[0140] The semiconductor nanoparticles and the semiconductor nanoparticles contained in the semiconductor nanoparticle composite cured film of the present invention The ligands coordinated to the surface of the nanoparticles constitute the semiconductor nanoparticle composite of the present invention. The semiconductor nanoparticle composite contained in the semiconductor nanoparticle composite cured film of the present invention is preferably: By configuring as described above, the semiconductor nanoparticle composite can be contained in the cured film at a higher mass fraction. The mass of the semiconductor nanoparticles in the cured film of the semiconductor nanoparticle composite can be The fraction is preferably 30% by mass or more, and more preferably 40% by mass or more. However, if the content is 70 mass % or more, the composition constituting the film will decrease, and the film will not become hard. It becomes difficult to form a solid.

[0141] The semiconductor nanoparticle composite cured film of the present invention contains semiconductor nanoparticle composites at a high mass fraction. Therefore, the absorbance of the semiconductor nanoparticle composite cured film can be increased. When the thickness of the semiconductor nanoparticle composite cured film is 10 μm, the normal For light with a wavelength of 450 nm coming from the direction, the absorbance should be 1.0 or more, and 1.3 or more is preferable. It is more preferable that the ratio is 1.5 or more, and even more preferable that the ratio is 1.5 or more.

[0142] Furthermore, the semiconductor nanoparticle composite cured film of the present invention contains semiconductor nanoparticles having high luminescence properties. Because it contains a particle composite, it is possible to provide a semiconductor nanoparticle composite cured film with high luminescence properties. The fluorescence quantum efficiency of the semiconductor nanoparticle composite cured film of the present invention is preferably 70% or more. It is preferable that the ratio is 80% or more.

[0143] The thickness of the semiconductor nanoparticle composite cured film of the present invention is determined based on the thickness of the semiconductor nanoparticle composite cured film. In order to miniaturize the device, it is preferable that the thickness is 50 μm or less, and more preferably 20 μm or less. It is more preferable that the thickness is 10 μm or less, and further more preferable that the thickness is 10 μm or less.

[0144] (Semiconductor nanoparticle composite patterned film and display element) The semiconductor nanoparticle composite patterned film is formed by using the semiconductor nanoparticle composite composition or The semiconductor nanoparticle composite composition can be obtained by forming a film pattern from the composition. The method for forming a pattern from the product and diluted composition is not particularly limited, and examples thereof include spin coating, These include bar coating, inkjet, screen printing, and photolithography. do.

[0145] The display element uses the semiconductor nanoparticle composite patterned film. For example, By using a semiconductor nanoparticle composite patterned film as a wavelength conversion layer, excellent fluorescence intensity can be obtained. It is possible to provide a display device with high efficiency.

[0146] The structures and / or methods described herein are provided by way of example only and are susceptible to numerous variations. Therefore, these specific examples or examples should not be construed in a limiting sense. It will be understood that the particular procedure or method described herein represents one of many methods of processing. Therefore, the various acts described and / or described may be The steps may be performed in the order listed or omitted. is mutable.

[0147] The subject matter of the present disclosure relates to the various methods, systems and configurations disclosed herein, as well as other Any novel and non-obvious combination of features, functions, acts, and / or properties of This includes all combinations and subcombinations thereof, and all equivalents thereof. [Example]

[0148] The present invention will be specifically described below with reference to examples and comparative examples, but the present invention is not limited to these. It is not something that is done.

[0149] (ligand) The ligands used in the examples and comparative examples were prepared as follows. PEG refers to polyethylene glycol chains, and is represented by the formula "-(CH2CH2O) n -CH3" The structure is expressed as follows. <Preparation of Ligands> (Method for preparing 1,1-dimethyl-3-oxobutyl mercaptopropionate) Add 4.2 g of 3-mercaptopropionic acid (40 mmol) and 4.7 g of dichloromethane to the flask. cetone alcohol (40 mmol), 5.4 g of 1-hydroxybenzotriazole (4 0 mmol), 100 mL of methylene chloride and 7.7 g of 1-ethyl-3-(3- Dimethylaminopropyl)carbodiimide (40 mmol) was mixed under a nitrogen atmosphere. The solution was allowed to react at room temperature for 60 minutes, and then the reaction solution was transferred to a separatory funnel and mixed with saturated sodium bicarbonate water, water, The organic phase was washed with saturated saline solution in turn, dried over magnesium sulfate, and The concentrate was then filtered and concentrated by evaporation. The desired ligand (mercaptoethanol) is purified by column chromatography using the developing solvent. 1,1-dimethyl-3-oxobutyl butapropionate) was obtained.

[0150] (Preparation method of thioglycolic acid PEG ester (molecular weight 470)) Add 3.7 g of thioglycolic acid (40 mmol) and 19.2 g of methoxy PE to a flask. G-OH (molecular weight 400, 48 mmol) and 0.2 g of concentrated sulfuric acid were mixed under a nitrogen atmosphere. The solution was stirred at 60°C, and the pressure was reduced to 30 mmHg or less, and the reaction was carried out for 24 hours. After cooling the reaction solution to room temperature, it was dissolved in toluene and washed successively with saturated sodium bicarbonate water, water, and saturated saline. The obtained organic phase was dried over magnesium sulfate, and then filtered and The desired ligand (thioglycolic acid PEG ester, molecular Amount 470) was obtained.

[0151] (Preparation method of thioglycolic acid PEG ester (molecular weight 760)) Methoxy PEG-OH (molecular weight 400, 48 mmol) was added to methoxy PEG-OH (molecular weight By changing the amount of thiol to 690, 48 mmol and preparing it in the same manner as above, a thiol with a molecular weight of 760 was obtained. Glycolic acid PEG ester was obtained.

[0152] (Preparation method of 3-mercaptopropionic acid PEG ester (molecular weight 550)) A flask was charged with 4.2 g of 3-mercaptopropionic acid (40 mmol) and 21.6 g of methyl PEG-OH (molecular weight 450, 48 mmol) and 0.2 g of concentrated sulfuric acid were added to a nitrogen atmosphere. The solution was stirred at 60°C under reduced pressure of 30 mmHg or less and reacted for 24 hours. The reaction solution was cooled to room temperature, dissolved in toluene, and then extracted with saturated sodium bicarbonate water, water, and saturated saline. The resulting organic phase was dried over magnesium sulfate, and then washed with The mixture was filtered and concentrated by evaporation to obtain the desired ligand (3-mercaptopropionic acid PEG ester, molecular weight 550) was obtained.

[0153] (Preparation method of 3-mercaptopropionic acid PEG ester (molecular weight 640)) Methoxy PEG-OH (molecular weight 450, 48 mmol) was added to methoxy PEG-OH (molecular weight The amount was changed to 550, 48 mmol) and the preparation was carried out in the same manner as above, to obtain 3- Mercaptopropionic acid PEG ester was obtained.

[0154] 2-[2-(2-acetoxyethoxy)ethoxy]ethyl 3-mercaptopropionate (How to adjust) Add 2.1 g of 3-mercaptopropionic acid (20 mmol) and 1.2 g of acetic acid to a flask. (20 mmol), 7.2 g of triethylene glycol (48 mmol), 100 mL of Toluene and 0.2 g of concentrated sulfuric acid were mixed under a nitrogen atmosphere. The solution was stirred at 110°C for 24 hours under a stirring device. After cooling at 40°C, the mixture was washed with saturated sodium bicarbonate water, water, and saturated saline in that order. After drying with magnesium, the concentrate was filtered and concentrated by evaporation. It was purified by column chromatography using hexane and ethyl acetate as developing solvents. The desired ligand (2-[2-(acetoxyethoxy)-3-mercaptopropionic acid] )ethoxy]ethyl) was obtained.

[0155] (Method for preparing 6-mercaptohexanoic acid PEG ester) A flask was charged with 5.9 g of 6-mercaptohexanoic acid (40 mmol) and 19.2 g of methionine. PEG-OH (molecular weight 400, 48 mmol) and 0.2 g of concentrated sulfuric acid were added under a nitrogen atmosphere. The solution was stirred at 60°C, and the pressure was reduced to 30 mmHg or less, and the mixture was allowed to react for 24 hours. The reaction solution was cooled to room temperature, dissolved in toluene, and then extracted with saturated sodium bicarbonate water, water, and saturated saline. The resulting organic phase was dried over magnesium sulfate, and then filtered. The desired ligand (6-mercaptohexanoic acid PE) was obtained by filtration and concentration by evaporation. G ester, molecular weight 530) was obtained.

[0156] (3-Mercaptopropionic acid 2-[2-(2-levulinoxyethoxy)ethoxy]ethyl) (How to adjust the A flask was charged with 2.1 g of 3-mercaptopropionic acid (20 mmol), 2.3 g of Lev Phosphoric acid (20 mmol), 6.0 g triethylene glycol (40 mmol), 5.4 g of 1-hydroxybenzotriazole (40 mmol), 100 mL of methylene chloride and and 7.7 g of 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide hydrochloride ( The solution was reacted at room temperature for 60 minutes, and then the reaction The solution was transferred to a separatory funnel and washed successively with saturated sodium bicarbonate water, water, and saturated saline. The organic phase was dried over magnesium sulfate, filtered, and concentrated by evaporation. This concentrate was subjected to column chromatography using hexane and ethyl acetate as developing solvents. The desired ligand (3-mercaptopropionic acid 2-[2-(2-levulinic acid) The resulting product was linoxy(ethoxy)ethoxy)ethyl.

[0157] (3-Mercaptopropionic acid 2-[2-[2-(2-hexyloxyethoxy)ethoxy]ethoxy Preparation of ethoxyethyl A flask was charged with 4.2 g of 3-mercaptopropionic acid (40 mmol) and 13.4 g of tetrahydrofuran. Triethylene glycol monohexyl ether (48 mmol), 100 mL of toluene and 0.2 g of concentrated sulfuric acid were mixed under a nitrogen atmosphere. A Dean-Stark apparatus was attached to the flask. The solution was stirred at 110°C for 24 hours. After cooling the reaction solution to room temperature, The organic phase was washed with saturated sodium bicarbonate water, water, and saturated saline in that order. After drying using a filtration gel, the concentrate was filtered and concentrated by evaporation. and purified by column chromatography using ethyl acetate as a developing solvent to obtain the desired product. The ligand (2-[2-[2-(2-hexyloxyethoxy)-3-mercaptopropionic acid) )ethoxy]ethoxy]ethyl) was obtained.

[0158] [Example 1] An InP-based semiconductor nanoparticle composite was prepared according to the following method. (Preparation of core particles) Indium acetate (0.3 mmol) and zinc oleate (0.6 mmol) were dissolved in oleic acid. Acid (0.9 mmol), 1-dodecanethiol (0.1 mmol), and octadecene (10 mL), heated to approximately 120°C under vacuum (<20 Pa), and reacted for 1 hour. The reaction mixture was reacted under vacuum, and then heated at 25°C under a nitrogen atmosphere to obtain tris(trimethylsilyl) After adding phosphine (0.2 mmol), the mixture was heated to about 300°C and reacted for 10 minutes. The reaction mixture was cooled to 25°C, and octanoic acid chloride (1.1 mmol) was added. After heating at 0°C for 30 minutes, the mixture was cooled to 25°C to obtain a dispersion of InP-based semiconductor nanoparticles.

[0159] (Precursor for shell formation) To prepare the shell, the following precursor was first prepared. (Preparation of Zn precursor solution) 40 mmol of zinc oleate and 75 mL of octadecene were mixed and heated under vacuum at 110°C. The mixture was heated at RT for 1 hour to prepare a Zn precursor with [Zn]=0.4M. (Preparation of Se precursor (trioctylphosphine selenide)) 22 mmol of selenium powder and 10 mL of trioctylphosphine were mixed in nitrogen. The mixture was stirred until dissolved to obtain trioctylphosphine selenide with [Se] = 2.2M. (Preparation of S precursor (trioctylphosphine sulfide)) 22 mmol of sulfur powder and 10 mL of trioctylphosphine were mixed under nitrogen. The mixture was stirred until dissolved to give trioctylphosphine sulfide with [S]=2.2M.

[0160] Using each of the precursors obtained as described above, the InP-based semiconductor nanoparticles (cores) were A shell was formed on the surface as follows. (Shell formation) The core dispersion was heated to 200°C. At 250°C, 6.0 mL of Zn precursor solution was added. and 2.0 mL of trioctylphosphine selenide were added and reacted for 30 minutes to form an InP-based semiconductor. A ZnSe shell was formed on the surface of the nanoparticles. 1.8 mL of trioctylphosphine sulfide was added, and the temperature was raised to 280°C and the reaction was carried out for 1 hour. A ZnS shell was formed. The obtained semiconductor nanoparticles were observed by STEM-EDS, and the core / shell structure was confirmed. It was confirmed that the structure The solution in which the synthesized core / shell-structured semiconductor nanoparticles were dispersed was The semiconductor nanoparticles were then aggregated by centrifugation (4000 rpm, 10 min). After the above steps, the supernatant was removed and the semiconductor nanoparticles were redispersed in hexane. Purified semiconductor nanoparticles were obtained.

[0161] (composition analysis) Elemental analysis of semiconductor nanoparticles was performed using a high-frequency inductively coupled plasma (ICP) and The ICP measurement was carried out using an X-ray fluorescence analyzer (XRF). After dissolving in nitric acid and heating, the sample was diluted with water and analyzed by an ICP emission spectrometer (Shimadzu Corporation, ICPS-81 00) was measured by the calibration curve method. The sample was placed in a pull holder and quantitative analysis was performed using an X-ray fluorescence analyzer (Rigaku, ZSX100e). The molar ratio of halogen to In in the semiconductor nanoparticles is shown in Table 1.

[0162] (Preparation of semiconductor nanoparticle composites) The purified semiconductor nanoparticles were placed in a flask at a mass ratio of 10% by mass. A 1-octadecene dispersion of semiconductor nanoparticles was prepared. 10.0 g of the 1-octadecene particle dispersion was placed in a flask, and the mercapto fatty acid ester 3.6 g of thioglycolic acid PEG ester (molecular weight 470) was used as a non-polar ligand. 0.4 g of dodecanethiol was added, and the mixture was stirred at 110°C for 60 minutes under a nitrogen atmosphere. The mixture was cooled to 5°C to obtain a semiconductor nanoparticle composite. The reaction mixture was transferred to a centrifuge tube and centrifuged at 4000 G for 20 minutes to obtain a clear 1-octadecane The 1-octadecene phase was removed, and the remaining semiconducting nanoparticle composite phase was The conductor nanoparticle composite phase was recovered. 5.0 mL of acetone was added to the obtained semiconductor nanoparticle composite phase to prepare a dispersion. 50 mL of normal hexane was added to the dispersion, and the mixture was centrifuged at 4000 G for 20 minutes. After centrifugation, the clear supernatant was removed and the precipitate was collected. This procedure was repeated several times. A purified semiconductor nanoparticle composite was obtained.

[0163] <Analysis> (Measurement of molecular weight of ligand) The molecular weight of the ligand was measured using a liquid chromatograph (LC-20: Shimadzu Corporation). This was carried out by GPC. First, the ligand was dissolved in THF (tetrahydrofuran). The eluate was collected in a column (KF-801, KF-803, KF-805: Shodex). The syneresis liquid was injected, and the number average molecular weight was calculated from the molecular weight distribution curve obtained. Polyethylene glycol (Polyethylene glycol) with a known average molecular weight is used. col READY_CAL SET Mp 102-40,000: Aldrich) Used.

[0164] (Fluorescence quantum efficiency measurement) The optical properties of the semiconductor nanoparticle composites were measured using a fluorescence quantum efficiency measurement system (Otsuka Electronics, QE-2 100) was used for the measurement. The semiconductor nanoparticle composite obtained by synthesis was dispersed in a dispersion medium. The emission spectrum was obtained by applying a single light of 450 nm as excitation light. The re-excitation correction spectrum is obtained by subtracting the re-excitation fluorescence emission spectrum from the spectrum. The fluorescence quantum efficiency (QY) and full width at half maximum (FWHM) were calculated from the emission spectrum after the measurement. The catalyst used was propylene glycol monomethyl ether acetate (PGMEA). The results are shown in Table 2.

[0165] ( 1 H-NMR measurement) The purified semiconductor nanoparticle complex was analyzed by analyzing the ligands coordinated to the semiconductor nanoparticles. The results were analyzed using a nuclear magnetic resonance (NMR) spectrometer (JNM-LA400 manufactured by JEOL Ltd.). In all measurements, deuterated chloroform was used as the solvent and tetrachloroform was used as the internal standard for chemical shifts. Using methylsilane, 1 The semiconductor nanoparticles obtained in Example 1 were measured using H-NMR. The complex contains a signal due to the alkyl group of dodecanethiol at around 0.8 to 1.6 ppm. and a signal due to the polyethylene glycol skeleton at around 3.5 to 4.0 ppm. The abundance ratio of each ligand was calculated from the area ratio of these signals. Based on the abundance ratio of each ligand, the average SP value of all ligands and the mercapto group for all ligands were calculated. The ratio of fatty acid esters was calculated. The results are shown in Tables 1 and 3.

[0166] (Thermogravimetric analysis) The purified semiconductor nanoparticle composite was heated to 550°C by differential thermogravimetry (DTA-TG). After heating, the sample was held for 10 minutes and then cooled. The residual mass after analysis was taken as the mass of the semiconductor nanoparticles. The mass ratio of the ligand to the semiconductor nanoparticles in the semiconductor nanoparticle complex (ligand / semiconductor nanoparticles) was calculated from the The results are shown in Tables 1 and 3.

[0167] (Dispersibility test) With reference to the mass ratio, the semiconductor nanoparticle composite was prepared so that the concentration of the semiconductor nanoparticles was 20 The organic dispersion medium was added so that the concentration was 0.0 mass%, 30.0 mass%, and 35.0 mass%, and at that time The dispersion state of the sample was checked. The sample that was dispersed was marked with a "○", and the sample that showed precipitation or turbidity was marked with a "○". Those that did not show the desired results are marked with "X" in Tables 2 and 4. Phenylidene methyl ether acetate (PGMEA) was used.

[0168] (Filterability test) A semiconductor nanoparticle composite PGMEA dispersion with a semiconductor nanoparticle concentration of 20.0 mass % was prepared. The filterability test was carried out on the samples that could be prepared. 1 mL of the composite PGMEA solution was measured into a syringe and poured into a PTFE syringe with a 0.45 μm aperture. The solution was filtered using a syringe filter (filter diameter 13 mm). Those that could be filtered are marked with "〇", and those that became clogged are marked with "×" in Table 2 and Table As described in 4.

[0169] (Heat resistance test) 50 mg of semiconductor nanoparticle composite was weighed into a sample tube and heated at 180°C in air. The sample was heated for 60 minutes. The sample was allowed to cool to room temperature, and 1 mL of chloroform was added. The dispersion state of the sample was checked. The sample that was dispersed was marked with "○", and the sample that showed precipitation or turbidity was marked with "○". Those that did not meet the criteria are marked with an "X" in Tables 2 and 4.

[0170] (Viscosity measurement) The semiconductor nanoparticle composite was mixed with isopropyl alcohol so that the concentration of the semiconductor nanoparticles was 30.0 mass %. The resulting dispersion was then dispersed in 25% hydroxybenzoate. Viscosity was measured using a TA Instruments AR-2000 rheometer at °C. Measurement takes 0.1 seconds. -1 After pre-shearing for 1 minute, -1 From the 1000s -1 The shear rate was varied from 100 s -1 The viscosity at If it is more than 30cp and less than 60cp, it is marked as "◎", if it is more than 30cp and less than 60cp, it is marked as "〇", if it is more than 60cp, it is marked as "〇", The results are shown in Tables 2 and 4. Samples for which the isobornyl acrylate dispersion could not be prepared are marked with a hyphen (-). Ta.

[0171] Example 2 In the process of producing semiconductor nanoparticle composites, 3-mercapto fatty acid ester is used. 3.2 g of PEG ester of butyropropionic acid (molecular weight 550) was used as an aliphatic ligand. A semiconductor nanoparticle composite was obtained in the same manner as in Example 1, except that 0.8 g of leic acid was used.

[0172] Example 3 In the process of preparing the semiconductor nanoparticle composite, thioglycol is used as the mercapto fatty acid ester. 3.2 g of PEG ester of carboxylic acid (molecular weight 470) was used, and 3-mercaptoethanol was used instead of the aliphatic ligand. A semiconductor was prepared in the same manner as in Example 1, except that 0.8 g of ethylhexyl captopropionate was used. The body-nanoparticle complex was obtained.

[0173] Example 4 In the process of producing semiconductor nanoparticle composites, 3-mercapto fatty acid ester is used. 6.4 g of PEG ester of butyropropionic acid (molecular weight 640) was used as an aliphatic ligand. A semiconductor nanoparticle composite was prepared in the same manner as in Example 1, except that 0.8 g of decanethiol was used. Got it.

[0174] Example 5 In the process of preparing the semiconductor nanoparticle composite, thioglycol is used as the mercapto fatty acid ester. 2.8 g of PEG ester of carboxylic acid (molecular weight 470) and dodecanethiol as an aliphatic ligand. A semiconductor nanoparticle composite was obtained in the same manner as in Example 1, except that 1.2 g of ethanol was used.

[0175] Example 6 In the process of preparing the semiconductor nanoparticle composite, thioglycol is used as the mercapto fatty acid ester. 2.4 g of PEG ester of carboxylic acid (molecular weight 470) and dodecanethiol as an aliphatic ligand A semiconductor nanoparticle composite was obtained in the same manner as in Example 1, except that 1.6 g of ethanol was used.

[0176] Example 7 When preparing the dispersion of the core particles, 0.45 mmol of octanoic acid chloride was added to the semiconductor nanoparticles. PEG 3-mercaptopropionate was used as the mercapto fatty acid ester when preparing the polymer complex. 3.6 g of ester (molecular weight 550), 0.4 g of dodecanethiol as an aliphatic ligand A semiconductor nanoparticle composite was obtained in the same manner as in Example 1, except that g was used.

[0177] Example 8 When preparing the dispersion of the core particles, 2.5 mmol of octanoic acid chloride was added to the semiconductor nanoparticle complex. When preparing the composite, 3-mercaptopropionic acid PEG ester was used as the mercapto fatty acid ester. The same procedure was carried out except that 3.8 g of ether was used as the aliphatic ligand and 0.2 g of dodecanethiol was used as the aliphatic ligand. A semiconductor nanoparticle composite was obtained in the same manner as in Example 1.

[0178] Example 9 In the process of producing semiconductor nanoparticle composites, 3-mercapto fatty acid ester is used. 2-[2-[2-(2-hexyloxyethoxy)ethoxy]ethoxy]butapropionic acid The same procedure was carried out except that 3.6 g of ethyl acetate and 0.4 g of dodecanethiol were used as the aliphatic ligand. A semiconductor nanoparticle composite was obtained in the same manner as in Example 1.

[0179] Example 10 In the process of producing semiconductor nanoparticle composites, 3-mercapto fatty acid ester is used. 3.8g of 2-[2-(2-levulinoxyethoxy)ethoxy]ethyl butapropionate The same method as in Example 1 was used except that 0.2 g of dodecanethiol was used as the aliphatic ligand. A semiconductor nanoparticle composite was obtained.

[0180] Example 11 In the process of producing semiconductor nanoparticle composites, 3-mercapto fatty acid ester is used. 3.6 g of 1,1-dimethyl-3-oxobutyl butanoate as an aliphatic ligand Semiconductor nanoparticles were synthesized in the same manner as in Example 1, except that 0.4 g of trioctylphosphine was used. A child complex was obtained.

[0181] Example 12 When preparing the dispersion of the core particles, 0.45 mmol of octanoic acid chloride was added to the semiconductor nanoparticles. When preparing the polymer complex, 3-mercaptopropionic acid 3-mercapto fatty acid ester was used. The other compounds used were 3.2 g of butyl ether and 0.8 g of dodecanethiol as an aliphatic ligand. A semiconductor nanoparticle composite was obtained in the same manner as in Example 1.

[0182] Example 13 When preparing the dispersion of the core particles, 2.5 mmol of octanoic acid chloride was added to the semiconductor nanoparticles. When preparing the complex, 1,1-3-mercaptopropionic acid was used as the mercapto fatty acid ester. 3.2 g of dimethyl-3-oxobutyl and 0.5 g of dodecanethiol as an aliphatic ligand. A semiconductor nanoparticle composite was obtained in the same manner as in Example 1, except that 8 g was used.

[0183] Example 14 In the process of producing semiconductor nanoparticle composites, 3-mercapto fatty acid ester is used. 2.8 g of 3-methoxybutyl butyrate and dodecanethiol as an aliphatic ligand. A semiconductor nanoparticle composite was obtained in the same manner as in Example 1, except that 1.2 g of ethanol was used.

[0184] Example 15 In the process of producing semiconductor nanoparticle composites, 3-mercapto fatty acid ester is used. 3.8 g of 2-[2-(2-acetoxyethoxy)ethoxy]ethyl butapropionate, The same method as in Example 1 was used except that 0.05 g of dodecanethiol was used as the aliphatic ligand. A semiconductor nanoparticle composite was obtained.

[0185] Example 16 In the process of producing semiconductor nanoparticle composites, 3-mercapto fatty acid ester is used. 2.8 g of 3-methoxybutyl butyrate, and benzenethiol instead of the aliphatic ligand. A semiconductor nanoparticle composite was obtained in the same manner as in Example 1, except that 1.2 g of ol was used.

[0186] Example 17 In the shell formation reaction, after the ZnSe shell was formed, the Zn precursor solution and trisulfide were The mixture was cooled to room temperature without adding octylphosphine. In the process of producing 1,1-dimethyl 3-mercaptopropionate as a mercapto fatty acid ester, 3.2 g of ethyl-3-oxobutyl and 0.8 g of dodecanethiol as an aliphatic ligand A semiconductor nanoparticle composite was obtained in the same manner as in Example 1, except that the above-mentioned compound was used.

[0187] (Comparative Example 1) In the process of preparing the semiconductor nanoparticle composite, thioglycol is used as the mercapto fatty acid ester. 9.6 g of PEG ester of carboxylic acid (molecular weight 760) and dodecanethiol as an aliphatic ligand. A semiconductor nanoparticle composite was obtained in the same manner as in Example 1, except that 0.8 g of ethanol was used.

[0188] (Comparative Example 2) When preparing the dispersion of the core particles, 4.5 mmol of octanoic acid chloride was added to the semiconductor nanoparticles. When preparing the complex, thioglycolic acid PEG ester (mol.) was used as the mercapto fatty acid ester. The molecular weight of 470 was 3.6 g, and 0.4 g of dodecanethiol was used as the aliphatic ligand. A semiconductor nanoparticle composite was obtained in the same manner as in Example 1.

[0189] (Comparative Example 3) In the process of producing semiconductor nanoparticle composites, 6-mercapto fatty acid ester is used. 3.2 g of butyrohexanoic acid PEG ester and 0 g of dodecanethiol as an aliphatic ligand were used. A semiconductor nanoparticle composite was obtained in the same manner as in Example 1, except that 0.8 g was used.

[0190] Comparative Example 4 In the process of preparing the semiconductor nanoparticle composite, thioglycol is used as the mercapto fatty acid ester. 2.0 g of PEG ester of carboxylic acid (molecular weight 470) and dodecanethiol as an aliphatic ligand A semiconductor nanoparticle composite was obtained in the same manner as in Example 1, except that 2.0 g of ethanol was used. Chloroform was used as a solvent for measuring the fluorescence quantum yield.

[0191] (Comparative Example 5) In the process of producing semiconductor nanoparticle composites, no mercapto fatty acid esters are added, and fatty Using 4.0 g of dodecanethiol as the aromatic ligand, the reaction was carried out at 110°C for 60 minutes under a nitrogen atmosphere. The mixture was stirred and cooled to 25°C to obtain a semiconductor nanoparticle composite. The reaction solution containing the complex was transferred to a centrifuge tube, 100 mL of acetone was added, and the mixture was centrifuged at 4000 G for 20 minutes. After centrifugation for a short time, the mixture was separated into a clear supernatant and a semiconductor nanoparticle composite phase. The remaining semiconductor nanoparticle composite phase was collected. 5.0 mL of normal hexane was added to prepare a dispersion. Seton was added and the mixture was centrifuged at 4000 G for 20 minutes. After centrifugation, the clear supernatant was removed. The precipitate was collected. This procedure was repeated several times. The rest of the procedure was the same as in Example 1. The semiconductor nanoparticle composite was obtained. Note that normal hexane was used as the solvent for measuring the fluorescence quantum yield. was used.

[0192] (Comparative Example 6) When preparing the dispersion of the core particles, 0.2 mmol of octanoic acid chloride was added to the semiconductor nanoparticles. When preparing the complex, 3-mercaptopropionic acid 3-methionine was used as the mercapto fatty acid ester. Except for the use of 3.2 g of butyl ether and 0.8 g of dodecanethiol as an aliphatic ligand, A semiconductor nanoparticle composite was obtained in the same manner as in Example 1.

[0193] (Comparative Example 7) In the process of preparing semiconductor nanoparticle composites, 3-mercapto fatty acid esters are used. 3.2 g of ethylhexyl isopropionate and 0 g of dodecanethiol as an aliphatic ligand. 0.8g, stirred at 110°C for 60 minutes under a nitrogen atmosphere, and cooled to 25°C. A semiconductor nanoparticle composite was obtained. The reaction solution containing the semiconductor nanoparticle composite was transferred to a centrifuge tube. Add 100 mL of acetone and centrifuge at 4000 G for 20 minutes to obtain a clear supernatant. The supernatant was removed and the remaining semiconductor nanoparticle composite was separated. The resulting semiconductor nanoparticle composite phase was added with 5.0 mL of normal hexane, and A dispersion was prepared. 50 mL of acetone was added to the obtained dispersion, and the mixture was stirred at 4000 G for 20 minutes. After centrifugation, the clear supernatant was removed and the precipitate was collected. The procedure was repeated several times. Otherwise, a semiconductor nanoparticle composite was obtained in the same manner as in Example 1. Chloroform was used as a solvent for measuring the fluorescence quantum yield.

[0194] (Comparative Example 8) In the process of producing semiconductor nanoparticle composites, 3-mercapto fatty acid ester is used. 3.2 g of 2-hydroxyethyl butadiene propionate, trioctyl as an aliphatic ligand A semiconductor nanoparticle composite was obtained in the same manner as in Example 1, except that 0.8 g of phosphine was used. This semiconductor nanoparticle complex was not dispersed in chloroform or PGMEA, and the fluorescence intensity was The yield could not be measured.

[0195] (Comparative Example 9) When preparing the dispersion of the core particles, 4.5 mmol of octanoic acid chloride was added to the semiconductor nanoparticles. When preparing the complex, 3-mercaptopropionic acid-3-mercapto fatty acid ester was used. The other compounds used were 3.6 g of butyl ether and 0.4 g of dodecanethiol as an aliphatic ligand. A semiconductor nanoparticle composite was obtained in the same manner as in Example 1.

[0196] (Comparative Example 10) The same procedure as in Example 1 was repeated except that octanoic acid chloride was not added when preparing the dispersion of core particles. A semiconductor nanoparticle composite was obtained in the same manner as described above.

[0197] (Comparative Example 11) When preparing the dispersion of core particles, 0.3 mm of indium chloride was used instead of indium acetate. The semiconductor was prepared in the same manner as in Example 1, except that octanoic acid chloride was not added. The body-nanoparticle complex was obtained. The indium chloride added during the preparation of the core particle dispersion generates hydrogen chloride as a by-product during synthesis. Therefore, in the semiconductor nanoparticles that are finally obtained, the halogen precursor is Compared with the case where a halogen precursor was added during the preparation of the core particle dispersion, It was found that the halogen content of

[0198] The meanings of the abbreviations shown in Tables 1 to 4 are as follows: MPAE: mercapto fatty acid ester QD: Semiconductor nanoparticles DDT: Dodecanethiol TOP: Trioctylphosphine EHMP: Ethylhexyl 3-mercaptopropionate PGMEA: Propylene glycol monomethyl ether acetate

[0199] [Table 1]

[0200] [Table 2]

[0201] [Table 3]

[0202] [Table 4]

[0203] As can be seen from the above results, in Examples 1 to 17, the semiconductor nanoparticle composites exhibited high fluorescence. It has high quantum efficiency (QY), excellent dispersibility in polar dispersion media, and high mass fraction. It is possible to distribute the rate. On the other hand, Comparative Example 5, which does not use mercapto fatty acid ester, Comparative Example 1 in which the molecular weight was too large, Comparative Example 3 in which the SP value of the mercapto fatty acid ester was too low, and Comparative Example 7: The average SP of the entire ligand is too low. Comparative Example 4: The average SP of the entire ligand is too low. In Comparative Example 8, which was too high, the dispersibility in a polar dispersion medium was poor, and the dispersibility at a high mass fraction was Dispersion is difficult. In addition, Comparative Examples 2, 6, 9, 10 and 11 However, since the halogen / In content of the semiconductor nanoparticles is outside the range specified in the present invention, the fluorescence intensity The efficiency was low and the filterability was also low.

[0204] In addition, the molecular weight of the mercapto fatty acid ester represented by the general formula (1) is 300 to 700. Examples 1 to 10 in the following ranges are excellent in heat resistance, and are compounds of the present invention represented by general formula (1) The mercapto fatty acid ester represented by the formula (I) has a molecular weight of 300 or more and 700 or less. The semiconductor nanoparticle composites are particularly suitable for applications where heat resistance is important. In Examples 1 to 10, the viscosity of the dispersion liquid when dispersed in a dispersion medium was Examples 11 to 17 using mercapto fatty acid esters represented by general formula (1) Although it is more expensive than the above, it can be used in applications other than those requiring low viscosity of the dispersion medium. is.

[0205] In addition, the molecular weight of the mercapto fatty acid ester represented by the general formula (1) is in the range of 300 or less. In Examples 11 to 17, the viscosity of the dispersion liquid when dispersed in the dispersion medium is low. In the present invention, as in Examples 11 to 17, a mercapto fatty acid represented by general formula (1) The semiconductor nanoparticle composite using an acid ester having a molecular weight of less than 300 has a molecular weight of A mercapto fatty acid ester represented by general formula (1) having a molecular weight of 300 or more and 700 or less is used. Although it does not have the heat resistance of Examples 1 to 10, it is more important to reduce the viscosity of the dispersion than to improve heat resistance. It was found that the above-mentioned composition is suitable for the intended use. [Explanation of symbols]

[0206] 1, 101 Blue LED 3, 103 LCD 7, 8 QD patterning 9 Diffusion Layer 11 cores 12 shells 102 QD Film 104 Color Filter(R) 105 Color Filter (G) 106 Color Filter (B)

Claims

1. A semiconductor nanoparticle composite in which a ligand is coordinated to the surface of a semiconductor nanoparticle, the semiconductor nanoparticles are core / shell type semiconductor nanoparticles containing at least In, P, and Cl; The ligand has the following general formula (1): HS-R １ -COO-R ２ (1) (In general formula (1), R １ represents an alkylene group having 1 to 3 carbon atoms, and R ２ represents a hydrophilic group.) The composition contains one or more mercapto fatty acid esters represented by the formula: the mercapto fatty acid ester has an SP value of 9.20 or more and a molecular weight of less than 300; the average SP value of the entire ligand is 9.10 to 11.00; and the mass ratio of the ligand to the semiconductor nanoparticles (ligand / semiconductor nanoparticles) is 0.40 or less; the semiconductor nanoparticle composite absorbs light in the range of 340 nm to 480 nm, emits light having an emission peak wavelength of 400 nm to 750 nm, has an emission spectrum with a full width at half maximum (FWHM) of 38 nm or less, and has a fluorescence quantum efficiency (QY) of 80% or more; A semiconductor nanoparticle composite characterized by:

2. 2. The semiconductor nanoparticle composite according to claim 1, wherein the content of the mercapto fatty acid ester represented by general formula (1) in the total amount of the ligands is 40 mol % or more.

3. 2. The semiconductor nanoparticle composite according to claim 1, wherein at least one of the shells is formed of ZnSe.

4. 2. The semiconductor nanoparticle composite according to claim 1, wherein the shell has two or more layers, and the outermost layer of the shell is formed of ZnS.

5. R in the general formula (1) ２ 2. The semiconductor nanoparticle composite according to claim 1, wherein: contains any one selected from the group consisting of an oligoethylene glycol group, a polyethylene glycol group, and an alkoxy group.

6. 2. The semiconductor nanoparticle composite according to claim 1, wherein the terminal group of R 2 not bonded to —COO— in the general formula (1) is any one selected from the group consisting of an alkyl group, an alkenyl group, and an alkynyl group.

7. The semiconductor nanoparticle composite according to claim 1 , wherein the ligand further comprises an aliphatic ligand.

8. The semiconductor nanoparticle composite according to claim 1, wherein the Cl content is 0.80 or more relative to the In content in atomic terms.

9. A semiconductor nanoparticle composite dispersion liquid in which the semiconductor nanoparticle composite according to any one of claims 1 to 7 is dispersed in a polar organic dispersion medium.

10. A semiconductor nanoparticle composite composition in which the semiconductor nanoparticle composite according to any one of claims 1 to 7 is dispersed in a monomer or a prepolymer.

11. A semiconductor nanoparticle composite cured film in which the semiconductor nanoparticle composite according to any one of claims 1 to 7 is dispersed in a polymer matrix.

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