JP2020045440A - Semiconductor fine particle composition, coating liquid using the composition, ink composition, and ink-jet ink, coating, printed matter, wavelength conversion film, color filter, light emitting element - Google Patents

Abstract

【Task】
An object of the present invention is to provide a coating liquid or an ink, particularly an ink that can be printed by an inkjet method, without impairing various characteristics of the semiconductor fine particle composition, particularly, the fluorescent characteristics of the quantum dots. Accordingly, it is an object of the present invention to provide a coated or printed material having excellent properties and stability over time, more specifically, a wavelength conversion film, a color filter, and a light-emitting element having excellent fluorescence characteristics.
[Solution]
The object is to provide a semiconductor fine particle composition comprising semiconductor fine particles and a coating material covering the surface of the particles, wherein the coating material has a structure represented by the following general formula (1) or general formula (2). Solved by things.
[Selection diagram] None

Description

  The present invention relates to a semiconductor fine particle composition and quantum dots, a coating liquid and an ink composition containing them, an inkjet ink, and coated and printed materials using them, a wavelength conversion film, a color filter, and a light emitting device.

The quantum dots that constitute the main component of the present invention are extremely small grains (dots) formed to confine electrons in a minute space in order to express unique optical characteristics according to quantum mechanics. The size of one quantum dot is 1 nanometer to several tens of nanometers in diameter, and is composed of about 10,000 atoms or less. In recent years, attention has been paid to the fact that the wavelength of emitted fluorescence can be continuously controlled by the size of the particles, and sharp emission having a highly symmetrical fluorescence intensity wavelength distribution can be obtained.
Quantum dots can adjust fluorescence to a wavelength that is easily transmitted through the human body, and can be delivered to any part of the body. Therefore, quantum dots can be used for bioimaging applications as a luminescent material (Non-Patent Document 1). Patent Literature 1), and development into applications for electronics and photonics (Patent Literatures 2 and 3) as clear light emitting materials and wavelength conversion materials are being studied.

When developing for these uses, it is necessary to form a fine pattern. A method has been proposed in which a resist solution is prepared using a photosensitive material for pattern formation, and light is irradiated through a mask (Patent Document 4). However, there has been a problem that the quantum dots are deteriorated when the photosensitive material or light is irradiated, and the quantum dots are also included in the portions to be removed by development, so that the efficiency of using the quantum dot material is low.
An ink-jet method is known as a method of not forming a resist, but a practical quantum dot ink that can be used in the ink-jet method has not yet been prepared.

  Also, as a problem of the current quantum dots themselves, although the luminous efficiency (quantum yield) is very high, the absorption efficiency of light, which is the excitation energy source, is not so high. It is necessary to devise such measures as using, thickening, and using a light-scattering substance in combination, and even if they are applied, they do not reach the level of conventional organic or inorganic fluorescent materials, or lower other required characteristics. There was something.

  On the other hand, when a quantum dot is used as a light emitting material of an electroluminescent device, it is necessary to make the quantum dot an excited state by recombining positive and negative charges injected from an electrode within (or near) the quantum dot. As a method of promoting the charge intake, for example, a design is adopted in which a conjugate structure such as an aromatic ring is introduced outside the quantum dot so that the charge flows into the quantum dot (Patent Documents 5 and 6). However, according to this method, even if the charge reaches the coating material on the surface of the quantum dot, recombination of positive and negative charges occurs on the quantum dot, and further, there is no guarantee that the excitation energy moves into the inside of the quantum dot.

JP 2006-216560 A JP 2008-112154 A JP 2009-251129 A JP-A-2015-127733 JP 2010-209141 A JP-T-2005-502176

Shintaka, "Semiconductor Quantum Dots, Their Synthesis and Application to Life Sciences," Production and Technology, Vol. 63, No. 2, 2011, p58-p65 Journal of the American chemical society 2007 129 15432-15433

  An object of the present invention is to provide coating liquids and inks, particularly inks that can be printed by an inkjet method, without impairing the properties of the semiconductor fine particle composition, particularly the fluorescent properties of quantum dots, and using the same. Accordingly, it is an object of the present invention to provide a coated or printed material having excellent properties and stability over time, more specifically, a wavelength conversion film, a color filter, and a light-emitting element having excellent fluorescence characteristics.

  The present inventors have conducted intensive studies to solve the above problems, and as a result, by using a compound having a specific structure as a coating material for quantum dots, without impairing various properties such as quantum dots, the coating liquid and the ink. In particular, it is possible to produce inks which can be printed by an ink-jet method, and to provide the above-mentioned coated products and printed materials using them, especially printed materials by an ink-jet method, and further provide a wavelength conversion film, a color filter, and a light-emitting element using them. I found something.

  That is, the present invention comprises semiconductor fine particles and a coating material covering the surface of the particles, and the coating material has a structure represented by the following general formula (1) or general formula (2). It relates to a particulate composition. The present inventions [1] to [16] are as follows.

[1] A semiconductor fine particle composition comprising semiconductor fine particles and a coating material covering the surface of the particles, wherein the coating material has a structure represented by the following general formula (1) or general formula (2). .
General formula (1)
General formula (2)

[In the general formulas (1) and (2),
X ^{1 to} X ⁴ are each independently N, S, O, NR ¹ , NR ² R ³ , OR ⁴ or SR ⁵ ;
Y ^{1 to} Y ⁵ are each independently C or N;
R ^{1 to} R ⁵ are each independently a hydrogen atom or a monovalent alkyl group which may have a substituent.
X ¹ Y ¹ Y ² X ² and X ³ Y ³ Y ⁴ Y ⁵ X ⁴ are π-conjugated,
X ^{1 to} X ⁴ and Y ^{1 to} Y ⁵ may form a ring structure Ar ^{1 to} Ar ⁷ containing adjacent groups,
When forming the ring structures Ar ^{1 to} Ar ⁷ ,
Ar ^{1 to} Ar ⁷ are each independently a divalent π-conjugated unit which may have a substituent,
X ¹ is a constituent atomic group of Ar ¹ or a group directly bonded to Ar ² ;
X ² is a constituent atomic group of Ar ³ or a group directly bonded to Ar ² ;
X ³ is a constituent atomic group of Ar ⁴ or a group directly bonded to Ar ⁵ ;
X ⁴ is a constituent atomic group of Ar ⁷ or a group directly bonded to Ar ⁶ . ]

[2] Any two or more of Ar ^{1 to} Ar ^{3 in} the general formula (1) or Ar ^{4 to} Ar ^{7 in} the general formula (2) may be condensed with adjacent π-conjugated units, The semiconductor fine particle composition according to [1], which is a 5- or 6-membered aromatic ring which may have a substituent.

[3] The semiconductor according to [1] or [2], wherein X ^{1 to} X ⁴ in the general formulas (1) and (2) are each independently N or OR ^4. Fine particle composition.

  [4] The coating material may have a substituent, and at least one selected from the group consisting of an 8-hydroxyquinoline ring, a benzoxazole ring, a benzothiazole ring, a benzimidazole ring, a benzotriazole ring, and a triazine ring. The semiconductor fine particle composition according to any one of [1] to [3], having a kind of ring structure.

  [5] The coating material according to any one of [1] to [4], wherein the coating material has a heteroaromatic ring structure represented by any of the following formulas (3) to (6). Semiconductor fine particle composition.

Equation (3)

Equation (4)

Equation (5)
[In the formula (5), Z represents O, S or NH. ]

Equation (6)

  [6] The semiconductor fine particle composition according to any one of [1] to [5], wherein the semiconductor fine particles are quantum dots.

  [7] The semiconductor fine particle composition according to any one of [1] to [6], further comprising a solvent.

  [8] The semiconductor fine particle composition according to any one of [1] to [7], further comprising a resin.

  [9] A coating liquid comprising the semiconductor fine particle composition according to any one of [1] to [8].

  [10] A coated article obtained by using the coating liquid according to [9].

  [11] An ink composition comprising the semiconductor fine particle composition according to any one of [1] to [8].

  [12] An inkjet ink comprising the ink composition according to [11].

  [13] A printed matter obtained by using the ink composition according to [11].

  [14] A wavelength conversion film formed on a substrate using the coating liquid according to [9] or the ink composition according to [11].

  [15] A color filter formed on a substrate using the coating liquid according to [9] or the ink composition according to [11].

  [16] A light-emitting element in which a light-emitting layer is formed on a substrate using the coating liquid according to [9] or the ink composition according to [11].

  According to the present invention, there is provided a coating liquid or an ink, particularly an ink which can be printed by an inkjet method, without impairing various characteristics of the semiconductor fine particle composition, particularly, a fluorescent characteristic of the quantum dot. In addition, a coating or printed matter having excellent properties and stability over time, more specifically, a wavelength conversion film, a color filter, and a light-emitting element having excellent fluorescence properties are provided using the composition.

  Hereinafter, the present invention will be described in detail.

<Semiconductor fine particle composition and quantum dots>
The quantum dot that constitutes the main component of the present invention is a composition composed of specific semiconductor fine particles, and the semiconductor fine particles are a semiconductor containing an inorganic substance as a component. It may be composed of a plurality of layers or more.
The semiconductor of the present invention is a simple substance selected from the group consisting of group 2 elements, 10 group elements, 11 group elements, 12 group elements, 13 group elements, 14 group elements, 15 group elements and 16 group elements; A semiconductor made of a compound containing at least one kind of element. Among them, a compound semiconductor is preferable. The compound semiconductor is at least two selected from the group consisting of Zn, Cd, B, Al, Ga, In, C, Si, Ge, Sn, N, P, As, Sb, Pb, S, Se, and Te. Is a semiconductor made of a compound containing the following elements. More preferably, it is selected from the group of elements represented by Zn, B, Al, Ga, In, C, Si, Ge, Sn, N, P, S, and Te, excluding elements that are concerned about human safety. A semiconductor made of a compound containing at least two kinds of elements. For applications that emit visible light, a semiconductor containing In as a constituent element is more preferable because of its narrow band gap.

As the material, more specifically, Group IV of the periodic table such as carbon (C) (amorphous carbon, graphite, graphene, carbon nanotube, diamond, etc.), silicon (Si), germanium (Ge), tin (Sn), etc. Elemental simple substance, simple substance of Group V element of the periodic table such as phosphorus (P) (black phosphorus), simple substance of Group VI element of the periodic table such as selenium (Se), tellurium (Te), tin oxide (IV) boron nitride (BN), boron phosphide (BP), boron arsenide (BAs), aluminum nitride (AlN), aluminum phosphide (AlP), aluminum arsenide (AlAs), aluminum antimonide (AlSb), gallium nitride (GaN), phosphorus Gallium arsenide (GaP), gallium arsenide (GaAs), gallium antimonide (GaSb), indium nitride (InN), indium phosphide (In) ), Indium arsenide (InAs), indium antimonide (InSb) periodic table compounds aluminum sulfide of a group III element and the periodic table group V element such as _{(Al 2 S} 3), aluminum selenide _(Al 2 _Se 3) Gallium sulfide (Ga ₂ S ₃ ), gallium selenide (GaSe, Ga ₂ Se ₃ ), gallium telluride (GaTe, Ga ₂ Te ₃ ), indium oxide (In ₂ O ₃ ), indium sulfide (In ₂ S ₃ , InS), indium selenide (In ₂ Se ₃ ), compounds of group III elements of the periodic table such as indium telluride (In ₂ Te ₃ ) and group VI elements of the periodic table, zinc oxide (ZnO), zinc sulfide ( ZnS), zinc selenide (ZnSe), zinc telluride (ZnTe), cadmium oxide (CdO), cadmium sulfide (CdS), Of cadmium lenide (CdSe), cadmium telluride (CdTe), mercury sulfide (HgS), mercury selenide (HgSe), mercury telluride (HgTe), etc. compounds, copper oxide (I) _(Cu 2 O) periodic table compounds of the group I element and periodic table group VI elements such as copper chloride (I) (CuCl), copper bromide (I) (CuBr), Compounds of a Group I element of the Periodic Table and a Group VII element of the Periodic Table, such as copper (I) iodide (CuI), silver chloride (AgCl), and silver bromide (AgBr). More than one species may be used in combination. These semiconductors may contain elements other than the constituent elements. For example, if the group III-V is taken as an example, an alloy system such as INGaP or INGaN may be used. In addition, semiconductor fine particles in which a rare earth element or a transition metal element is doped in the above materials are also used. For example, ZnS: Mn, ZnS: Tb, ZnS: Ce, LaPO ₄ : Ce, and the like can be given.

Among them, silicon (Si), germanium (Ge), gallium nitride (GaN), gallium phosphide (GaP), gallium arsenide (GaAs), indium nitride (InN), indium phosphide (InP), indium arsenide (InAs), Gallium selenide (GaSe, Ga ₂ Se ₃ ), indium sulfide (In ₂ S ₃ , InS), zinc oxide (ZnO), zinc sulfide (ZnS), zinc selenide (ZnSe), zinc telluride (ZnTe), oxide Cadmium (CdO), cadmium sulfide (CdS), cadmium selenide (CdSe), cadmium telluride (CdTe), alloys such as InGaP, InGaN, and the like are preferably used. In particular, indium phosphide (InP), cadmium selenide (CdSe), zinc sulfide (ZnS), zinc selenide (ZnSe) Particularly preferably used.

Further, as a material of the semiconductor fine particles, a perovskite crystal can also be preferably used. The perovskite crystal suitable as the quantum dot of the present invention has a composition represented by the following general formula (7) and has a three-dimensional crystal structure.
General formula (7): AB (Hal) ₃
[In the general formula (7), A is a monovalent cation of an amine compound which is at least one selected from methylammonium (CH ₃ NH ₂ ) and formamidinium (NH ₂ CHNH), or R is a monovalent cation of at least one alkali metal element selected from rubidium (Rb), cesium (Cs), and francium (Fr), and B is at least one selected from lead (Pb) and tin (Sn). Hal is a monovalent anion of at least one halogen element selected from iodine (I), bromine (Br), and chlorine (Cl). ]

The core / shell type semiconductor fine particles suitably used in the present invention have a structure in which the core structure is coated with a semiconductor component different from the semiconductor component forming the core. Since the outside is a semiconductor having a large band gap, excitons (electron-hole pairs) generated by energy excitation such as light are confined in the core. As a result, the probability of non-radiative transition on the surface of the semiconductor fine particles is reduced, and the quantum yield of light emission and the stability of the fluorescent properties of the semiconductor quantum dots are improved. When used as a quantum dot, suitable combinations of materials satisfying the above conditions include CdSe / ZnS, CdSe / ZnSe, CdS / ZnS, CdSe / CdS, CdTe / CdS, InP / ZnS, PbSe / PbS, GaP / ZnS, Si / ZnS, InN / GaN, InP / CdSSe, InP / ZnSeTe, InGaP / ZnSe, InGaP / ZnS, Si / AlP, InP / ZnSTe, InGaP / ZnSTe, InGaP / ZnSSe, and the like.
As the shell component of the fine particles, ZnS, CdS, ZnSe, etc. are often used. Among them, in the case of semiconductor fine particles containing In as a constituent element of the fine particles, ZnS has no elemental toxicity, and is used as a quantum dot. It is particularly excellent in characteristics such as exciton confinement and is preferably used.

  The average particle size of the inorganic material portion of the semiconductor fine particles of the present invention is preferably 0.5 nm to 100 nm, and a particle size that can obtain desired characteristics can be selected. In the case of the core / shell type, a plurality of shell fine particles may be contained in one semiconductor fine particle. In the case of a single semiconductor composition, the average particle diameter of the semiconductor fine particles and the average particle diameter of the core / shell type core are preferably 0.5 nm to 10 nm. Synthesis with an average particle diameter of less than 0.5 nm is difficult, and in the case of a quantum dot, if it exceeds 10 nm, the quantum confinement effect cannot be obtained, and the desired fluorescence cannot be obtained. The quantum dot is characterized in that the fluorescence wavelength can be arbitrarily changed by changing the core particle diameter even with the same material, and the particle diameter is set according to the required fluorescence wavelength. The average shell thickness is equivalent to the difference between the particle radius of the inorganic material portion and the core particle radius.If the shell thickness is too small, the strength and confinement effect of the shell are not sufficient. In the case of using a working liquid or ink, the dispersibility is poor, or in the case of quantum dots, it becomes difficult to excite the core depending on the excitation method. Further, the average particle diameter of the whole fine particles including the coating material is preferably 2 nm to 1 μm. The shape of the semiconductor fine particles is not limited to a spherical shape, but may be a rod shape, a disk shape, or another shape.

  When the semiconductor fine particles of the present invention are quantum dots, the quantum dots in the coating liquid or ink, such as red and green, in order to obtain a plurality of emission peaks, a plurality of types of quantum dots having different particle diameters corresponding thereto. Can be used in combination, and the ratio can be freely selected within the range of the content in the ink in total.

<Coating material>
The semiconductor fine particles of the present invention can be used by exposing the inorganic material portion, but it is necessary at the time of fine particle preparation, stability when used as a coating liquid or ink, coating, printability, and coating. It is preferable that the material or the printed material is coated with an organic material in order to exhibit characteristics when the product is in the final form and improve environmental resistance such as stability over time. These organic substances are often referred to as a coating material or a protective material. In particular, they are often referred to as a treating agent for the surface of fine particles during synthesis, and in the case of quantum dots, as a ligand or a ligand.

  The coating material of the present invention has a structure represented by the general formula (1) or the general formula (2).

General formula (1)

General formula (2)

[In the general formulas (1) and (2),
X ^{1 to} X ⁴ are each independently N, S, O, NR ¹ , NR ² R ³ , OR ⁴ or SR ⁵ ;
Y ^{1 to} Y ⁵ are each independently C or N;
R ^{1 to} R ⁵ are each independently a hydrogen atom or a monovalent alkyl group which may have a substituent.
X ¹ Y ¹ Y ² X ² and X ³ Y ³ Y ⁴ Y ⁵ X ⁴ are π-conjugated,
X ^{1 to} X ⁴ and Y ^{1 to} Y ⁵ may form a ring structure Ar ^{1 to} Ar ⁷ containing adjacent groups,
When forming the ring structures Ar ^{1 to} Ar ⁷ ,
Ar ^{1 to} Ar ⁷ are each independently a divalent π-conjugated unit which may have a substituent,
X ¹ is a constituent atomic group of Ar ¹ or a group directly bonded to Ar ² ;
X ² is a constituent atomic group of Ar ³ or a group directly bonded to Ar ² ;
X ³ is a constituent atomic group of Ar ⁴ or a group directly bonded to Ar ⁵ ;
X ⁴ is a constituent atomic group of Ar ⁷ or a group directly bonded to Ar ⁶ . ]

Many of the compounds having a structure represented by the general formula (1) or (2) are known as chelating ligands in a metal complex, stabilizing a metal atom, and furthermore, a compound between the metal atom and the ligand. Many exhibit strong absorption due to strong electronic interaction, and some exhibit strong fluorescence. By utilizing these properties of the metal complex, it can be used as a dye, and those having sublimability or solvent solubility can also be used as a light emitting material or a charge transport material in an electroluminescent device. In the present invention, instead of coordinating to a single metal atom, it is adsorbed to metal atoms on the surface of the semiconductor fine particles. Instead, the fine particles are more strongly coated and stabilized by binding with at least two adsorbing groups consisting of X ¹ and X ² linked by π conjugation. Furthermore, like the metal complex, the π-conjugated system integrated with the ring structure shows strong light absorption, and the irradiated light can be used efficiently, and the excitation energy obtained by absorption is absorbed through the adsorbed metal atom. It is possible to efficiently feed the inside of the fine particles. In addition, when used in an electroluminescent device, it has a π-conjugated ring and thus has a charge transporting property, so that charges can be efficiently taken in. In addition, through the bond between the adsorptive group and the metal atom, the excitation energy generated by the recombination of positive and negative charges on the coating material can be efficiently sent into the fine particles, and the positive and negative charges can be sent into the fine particles from different coating materials. Thus, recombination excitation can be caused in the fine particles.

In the present invention, specific examples of the π-conjugated unit which may be formed by the general formula (1) or the general formula (2) include:
Substituted or unsubstituted aromatic rings or condensation such as benzene, toluene, xylene, ethylbenzene, naphthalene, anthracene, phenanthrene, fluorene, pyrene, chrysene, naphthacene, perylene, azulene, fluorenone, anthraquinone, dibenzosuberenone, tetracyanoquinodimethane, etc. A group consisting of an aromatic ring,
Furan, thiophene, pyrrole, pyridine, pyrone, oxazole, pyrazine, triazine, oxadiazole, triazole, thiadiazole, indole, quinoline, isoquinoline, carbazole, acridine, thioxanthone, coumarin, acridone, diphenylene sulfone, quinoxaline, benzoxazole, benzo Thiazole, benzimidazole, benzotriazole, phenazine, phenanthroline, phenothiazine, quinacridone, flavanthrone, a group consisting of a substituted or unsubstituted heteroaromatic ring or fused heteroaromatic ring such as indanthrone,
Biphenyl, terphenyl, binaphthyl, bifluorenylidene, bipyridine, biquinoline, flavone, phenyltriazine, bisbenzothiazole, bithiophene, phenylbenzotriazole, phenylbenzimidazole, phenylacridine, bis (benzoxazolyl) thiophene, bis (phenyl) Oxazolyl) benzene, biphenylylphenyloxadiazole, diphenylbenzoquinone, diphenylisobenzofuran, diphenylpyridine, stilbene, dibenzyl, diphenylmethane, bis (phenylisopropyl) benzene, diphenylfluorene, diphenylhexafluoropropane, dibenzylnaphthyl ketone, diphenyl Benzylidenecyclohexanone, distyrylnaphthalene, (phenylethyl) benzylnaphthalene, Phenyl ether, methyldiphenylamine, benzophenone, phenyl benzoate, diphenylurea, diphenylsulfide, diphenylsulfone, diphenoxybiphenyl, bis (phenoxyphenyl) sulfone, bis (phenoxyphenyl) propane, diphenoxybenzene, ethylene glycol diphenyl ether, neopentyl glycol A group having a skeleton in which two or more of the same or different two or more ring structural units such as diphenyl ether, dipicolylamine, and dipyridylamine are linked; and the like.
Among these, a group consisting of the compounds exemplified as the substituted or unsubstituted aromatic ring, fused aromatic ring, heteroaromatic ring, and fused heteroaromatic ring is preferable.

In the structure represented by the general formula (1) or (2), at least two of each of Ar ^{1 to} Ar ³ of the general formula (1) or Ar ^{4 to} Ar ⁷ of the general formula (2) are: The ring structure is preferably a ring structure which may be condensed with each other or may have a substituent, and the ring structure is preferably an aromatic ring or a heteroaromatic ring, and more preferably from the viewpoint of stabilizing a π-conjugated system. It is a 5- or 6-membered aromatic or heteroaromatic ring, and Y ^{1 to} Y ⁵ are preferably atoms constituting a ring structure which is a conjugate unit.

X ¹ and X ^{2 in} the general formula (1) or X ³ and X ^{4 in} the general formula (2) are preferably coordinated to the same metal element on the surface of the semiconductor fine particles, and are preferably N or OH. More preferably, X ¹ and X ² are N and OH, or X ³ and X ⁴ are N and OH. In addition, one hydrogen on X ¹ or X ² of the general formula (1) or X ³ or X ⁴ of the general formula (2) is eliminated and coordinated to the metal element as a monovalent anion. Is preferred.

  Hereinafter, typical examples of the coating material having the structure represented by the general formula (1) or the general formula (2) of the present invention are specifically exemplified in Tables 1 to 6, and the present invention is not limited thereto. It is not limited.

  For many of the coating materials listed in Tables 1 to 6, commercially available reagents and industrial raw materials can be used as they are. Other target compounds can be appropriately synthesized by introducing or converting a substituent, coupling a partial structure, or the like.

  As the coating material, at least one selected from the group consisting of an 8-hydroxyquinoline ring, a benzoxazole ring, a benzothiazole ring, a benzimidazole ring, a benzotriazole ring, and a triazine ring, which may have a substituent. It preferably has a ring structure, and more preferably has a heteroaromatic ring structure represented by any of the following formulas (3) to (6). These ring structures may have a substituent.

Equation (3)

Equation (4)

Equation (5)
[In the formula (5), Z represents O, S or NH. ]

Equation (6)

  That is, among the coating materials listed in Tables 1 to 6, particularly preferable ones are compounds (1), (2), (3), (47), and (4) as compounds belonging to formula (3). Compounds belonging to compounds (58), (59), (60), compounds belonging to formula (5), compounds (44), (45), (52), compounds belonging to formula (6) (41).

  The coating material of the present invention can be used as a treating agent at the time of synthesizing the semiconductor fine particles. However, due to the difference in properties, there is a risk that the synthesis does not proceed well or the coating material itself is deteriorated during the synthesis. is there. For this reason, it is rather preferable to use a general treating agent at the time of synthesis and replace the coating material with the coating material of the present invention later.

  The organic substance that can be used as a treating agent at the time of synthesizing the semiconductor fine particles of the present invention has a strong polarity adsorbed on the metal portion of the inorganic semiconductor fine particles, or has an unshared electron pair, and further has a carbon chain or an aromatic ring linked thereto. Is an organic substance having a partial structure having a high affinity for a solvent or a resin used as a coating liquid or an ink by having the above-mentioned structure, a polyalkylene glycol structure or the like. Such organic substances are generally well-known as dispersants for organic and inorganic pigments and inorganic compound materials, surfactants and emulsifiers used in detergents and emulsion formation, and the like. In the invention, these compounds can be used. A compound having a partial structure used as a ligand (ligand) of a metal complex, particularly a compound having a chelate ligand structure having two or more coordination sites to a metal, is adsorbed to the metal portion of the semiconductor fine particles. It can be used because it is easy to remove and hard to remove. In particular, an organic substance which can be used as a treating agent in the synthesis in the present invention has a high boiling point and is expected to have an interaction of an alkyl chain portion, and is preferably an organic substance having an alkyl group having 8 or more carbon atoms as a partial structure. Further, it is better to have a polar group in order to strengthen the action on the semiconductor fine particles. Examples of the organic substance that can be treated include an organic acid, an organic amine, a sulfur-containing organic substance, and a phosphorus-containing organic substance.

As the organic acid, a compound having a carboxylic acid group at a terminal, which may have an aromatic ring or an ether group, can be used. Specific examples include benzoic acid, biphenylcarboxylic acid, butylbenzoic acid, hexylbenzoic acid, cyclohexylbenzoic acid, naphthalenecarboxylic acid, hexanoic acid, heptanoic acid, octanoic acid, ethylhexanoic acid, hexenoic acid, octenoic acid, citronellic acid, suberin Acid, ethylene glycol bis (4-carboxyphenyl) ether, (2-butoxyethoxy) acetic acid and the like.
The organic acid having an alkyl group having 8 or more carbon atoms as a partial structure is a compound having an alkyl group having 8 or more carbon atoms among organic acids, and specifically, nonanoic acid, decanoic acid, lauric acid, and myristine. Acids, palmitic acid, stearic acid, tricosanoic acid, lignoceric acid, oleic acid, eicosadienoic acid, linolenic acid, sebacic acid, (2-octyloxy) acetic acid, and the like.

  As the organic amine, a compound having an amino group at a terminal which may have an aromatic ring or an ether group can be used. Specific examples include n-butylamine, iso-butylamine, tert-butylamine, n-hexylamine, n-heptylamine, and cyclohexylamine. Examples of the organic amine having an alkyl group having 8 or more carbon atoms as a partial structure include octylamine, dodecaamine, heptadecane-9-amine, and N, N-dimethyl-n-octylamine.

Examples of the sulfur-containing organic substance include thiols and disulfides which may have an aromatic ring and an ether group.
As thiols, allyl mercaptan, 1,3-benzenedimethanethiol, 2-amino-5-mercapto-1,3,4-thiadiazole, 3-amino-5-mercapto-1,2,4-triazolebutanethiol , N-hexanethiol, n-heptanethiol, and the like. Examples of the sulfur-containing organic substances of thiols having an alkyl group having 8 or more carbon atoms as a partial structure include dodecanethiol, 1-docosanthiol, tert-dodecylmercaptan and the like.
Examples of the disulfide include bis (4-chloro-2-nitrophenyl) disulfide, hexyl sulfide, 3,3 ′, 5,5′-tetrachlorodiphenyl disulfide, and the like. Examples of the sulfur-containing organic substances of sulfides having an alkyl group having 8 or more carbon atoms as a partial structure include dodecyl disulfide, octadecyl disulfide, dodecyl octadecyl disulfide, and the like.

As the phosphorus-containing organic substance, a compound which may have an aromatic ring or an ether group and has a terminal phosphate group can be used. Specific examples include butyl phosphate, hexyl phosphate, diisopropyl phosphate, mono-2-ethylhexyl (2-ethylhexyl) phosphonate, propyl phosphonic acid, hexyl phosphonic acid, methyl hexyl phosphonate, hexyl isopropyl phosphonate, and the like. .
Examples of the phosphorus-containing organic substance having an alkyl group having 8 or more carbon atoms as a partial structure include octyl phosphate, didodecyl phosphate, dodecyl phosphate, dodecylphosphonic acid, dodecyl hexylphosphonate, decylphosphonic acid, and isopropyl decylphosphonate. Can be

  The organic substance that can be used as a treating agent at the time of synthesis may have a plurality of groups selected from the same or different groups among the above organic acid groups, amino groups, sulfur-containing groups, and phosphorus-containing groups.

  As a method for synthesizing the semiconductor fine particles of the present invention, generally known methods such as a method for preparing in a glass, a method for synthesizing in an aqueous solution, and a method for synthesizing in an organic solvent can be used. In particular, regarding the InP / ZnS core-shell type quantum dots, the technical documents “Journal of American Chemical Society. 2007, 129, 15432-15433”, “Journal of American Chemical Society. 2016, 138, 5923-592Zn core”. Technical documents "Journal of American Chemical Society. 2009, 131, 5691-5697" for quantum dots, technical documents "Chemistry of Materials. 2009, 21, 4222-2429", and technical documents "Journalic anonymous company for Si quantum dots. .2010, 132, 2 48-253 ", and can be synthesized.

  Exchange of the semiconductor fine particle composition surface-treated with the treating agent used in the synthesis to the coating material of the present invention is performed by mixing the surface-treated semiconductor fine particle composition with the coating material of the present invention and stirring in a solvent, or After the solvent is roughly removed from the treated semiconductor fine particle composition by centrifugal sedimentation or the like, the method can be performed by, for example, redispersing the semiconductor fine particles in the solvent containing the coating material of the present invention. By performing a surface treatment on a coating material having a high affinity with a desired solvent or resin suitable for a coating liquid or an ink, a final form of a target coated product or printed material can be obtained as described above. As a result, the semiconductor fine particle composition, particularly a composition having very high characteristics as a quantum dot, can be suitably used in the final form. The coating material of the present invention may be used in combination with the above-mentioned general synthesis processing agent as a coating material when synthesizing, or when forming a coating liquid or ink.

<Solvent and resin, additive>
The solvent used in the present invention includes toluene, 1,2,3-trichloropropane, 1,3-butylene glycol, 1,3-butylene glycol diacetate, 1,4-dioxane, 2-heptanone, 2-methyl -1,3-propanediol, 3,5,5-trimethyl-2-cyclohexen-1-one, 3,3,5-trimethylcyclohexanone, ethyl 3-ethoxypropionate, 3-methyl-1,3-butanediol , 3-methoxy-3-methyl-1-butanol, 3-methoxy-3-methylbutyl acetate, 3-methoxybutanol, 3-methoxybutyl acetate, 4-heptanone, m-xylene, m-diethylbenzene, m-dichlorobenzene , N, N-dimethylacetamide, N, N-dimethylformamide, n-butyl alcohol, n-butylbenzene, n-propyl acetate, N-methylpyrrolidone, o-xylene, o-chlorotoluene, o-diethylbenzene, o-dichlorobenzene, P-chlorotoluene, P-diethylbenzene, sec-butylbenzene, tert-butylbenzene, γ-butyrolactone , Water, methanol, ethanol, isopropyl alcohol, tertiary tert-butanol, isobutyl alcohol, isophorone, ethylene glycol diethyl ether, ethylene glycol dibutyl ether, ethylene glycol monoisopropyl ether, ethylene glycol monoethyl ether, ethylene glycol monoethyl ether acetate, ethylene Glycol monotertiary butyl ether, ethylene glycol monobutyl ether, ethylene glycol monobutyl Ether acetate, ethylene glycol monopropyl ether, ethylene glycol monohexyl ether, ethylene glycol monomethyl ether, ethylene glycol monomethyl ether acetate, diisobutyl ketone, diethylene glycol diethyl ether, diethylene glycol dimethyl ether, diethylene glycol monoisopropyl ether, diethylene glycol monoethyl ether acetate, diethylene glycol monobutyl ether , Diethylene glycol monobutyl ether acetate, diethylene glycol monomethyl ether, cyclohexanol, cyclohexanol acetate, cyclohexanone, dipropylene glycol dimethyl ether, dipropylene glycol methyl ether acetate, Propylene glycol monoethyl ether, dipropylene glycol monobutyl ether, dipropylene glycol monopropyl ether, dipropylene glycol monomethyl ether, diacetone alcohol, triacetin, tripropylene glycol monobutyl ether, tripropylene glycol monomethyl ether, propylene glycol diacetate, propylene glycol Phenyl ether, propylene glycol monoethyl ether, propylene glycol monoethyl ether acetate, propylene glycol monobutyl ether, propylene glycol monopropyl ether, propylene glycol monomethyl ether, propylene glycol monomethyl ether acetate, propylene glycol monomethyl ether Propionate, benzyl alcohol, methyl isobutyl ketone, methyl cyclohexanol, acetic acid n- amyl acetate n- butyl, isoamyl acetate, isobutyl acetate, propyl acetate, and dibasic acid esters.

Among these, in order to perform printing by the ink jet method, it is necessary that the solvent has a boiling point at normal pressure of 120 ° C. or higher in order to prevent drying by the discharge head. Examples of solvents having a boiling point of 120 ° C. or higher at normal pressure are given. 1,4-butanediol (228 ° C.), 1,3-butanediol (208 ° C.), 2-ethyl-1-hexanol (185 ° C.), benzyl alcohol (205 ° C.), diisobutyl ketone (168 ° C.), cyclohexanone ( 156 ° C), diacetone alcohol (168 ° C), butyl acetate (121 ° C), methoxybutyl acetate (171 ° C), cellosolve acetate (156 ° C), propylene glycol monomethyl ether acetate (146 ° C), amyl acetate (130 ° C) Methyl lactate (145 ° C) ethyl lactate (154 ° C), butyl lactate (188 ° C), ethylene glycol monomethyl ether acetate (145 ° C), ethylene glycol monomethyl ether (125 ° C), ethylene glycol monoethyl ether (134 ° C), Ethylene glycol monobutyl ether (17 1 ° C.), ethylene glycol (197 ° C.), propylene glycol (187 ° C.), propylene glycol monomethyl ether (121 ° C.), methoxymethyl butanol (173 ° C.), diethylene glycol dimethyl ether (162 ° C.), ethylene glycol diethyl ether (121 ° C.) , Perchloroethylene (121 ° C), dichlorobenzene (180 ° C), N-methyl-2-pyrrolidone (202 ° C), dimethylformamide (153 ° C), ethyl 3-ethoxypropionate (170 ° C), γ-butyrolactone ( 203 ° C.) and dimethylsulfoxyside (189 ° C.).
From the viewpoint of solubility, a hydrocarbon solvent having a boiling point of 120 ° C. or more at normal pressure is preferable, and an aromatic hydrocarbon solvent having a boiling point of 120 ° C. or more at normal pressure is particularly preferable.

Octane (125 ° C), decane (174 ° C), 1-decene (171 ° C), decahydronaphthalene (191 ° C), and butylcyclohexane (180 ° C) include hydrocarbon solvents having a boiling point of 120 ° C or more at normal pressure. , 2,3, -dimethylheptane (140 ° C).
Examples of aromatic hydrocarbon solvents having a boiling point of 120 ° C. or higher at normal pressure include xylene (138 ° C.), mesitylene (164 ° C.), methylnaphthalene (245 ° C.), tert-butylbenzene (168 ° C.), and n-butylbenzene. (183 ° C.).

Further, the inkjet ink of the present invention may also contain a solvent having a boiling point of less than 120 ° C. Examples of the contained solvent include methanol, ethanol, isopropyl alcohol, normal propyl alcohol, butanol, isobutanol, tert-butanol, acetone, methyl ethyl ketone, methyl isobutyl ketone, ethyl acetate, methyl acetate, normal propyl acetate, isopropyl acetate, 1,4 -Dioxane, methyl tert-butyl ether, isopropyl ether), ethylene glycol dimethyl ether, methylene chloride, trichloroethylene, fluorocarbon, bromopropane, chloroform, tetrahydrofuran, dimethyl carbonate, diethyl carbonate, acetonitrile, 1,3-dioxolan and the like.
It is preferable that the solvent having a boiling point of less than 120 ° C. is mixed within a range of 0 to 60% of the volatile components. If the content is more than this, drying of the ink is accelerated, and it may be difficult to discharge the ink jet.

  Examples of the resin include petroleum resin, maleic acid resin, nitrocellulose, cellulose acetate butyrate, cyclized rubber, chlorinated rubber, alkyd resin, acrylic resin, polyester resin, amino resin, vinyl resin, and butyral resin. It can be selected as appropriate depending on the coating, printing method and base material. Further, as resins that may be contained, linear olefin resins, aromatic polyether resins, polyimide resins, fluorene polycarbonate resins, fluorene polyester resins, polycarbonate resins, polyamide (aramid) resins, polyarylates Resin, polysulfone resin, polyethersulfone resin, polyparaphenylene resin, polyamideimide resin, polyethylene naphthalate (PEN) resin, fluorinated aromatic polymer resin, (modified) acrylic resin, epoxy Resins, allyl ester-based curable resins, and silsesquioxane-based ultraviolet curable resins.

  A surfactant may be added to the coating liquid and the ink of the present invention for the purpose of adjusting the surface tension and ensuring the wettability of the ink on the printing substrate. In the present invention, any of cationic, anionic, amphoteric, and nonionic surfactants can be used.

  Examples of the cationic surfactant include fatty acid amine salts, aliphatic quaternary ammonium salts, benzalkonium salts, benzethonium chloride, pyridinium salts, imidazolinium salts and the like.

  Examples of the anionic surfactant include fatty acid soap, N-acyl-N-methylglycine salt, N-acyl-N-methyl-β-alanine salt, N-acylglutamate, acylated peptide, alkyl sulfonate, Alkyl benzene sulfonate, alkyl naphthalene sulfonate, dialkyl sulfosuccinate, alkyl sulfo acetate, α-olefin sulfonate, N-acylmethyl taurine, sulfated oil, higher alcohol sulfate, secondary higher alcohol Sulfate, alkyl ether sulfate, secondary higher alcohol ethoxy sulfate, fatty acid alkylolamide sulfate, alkyl ether phosphate, alkyl phosphate, and the like.

Examples of the amphoteric surfactant include a carboxybetaine type, a sulfobetaine type, an aminocarboxylate, and imidazolinium betaine.
Examples of the nonionic surfactant include polyoxyethylene secondary alcohol ether, polyoxyethylene alkylphenyl ether, polyoxyethylene sterol ether, polyoxyethylene lanolin derivative polyoxyethylene polypropylene alkyl ether, polyoxyethylene glycerin fatty acid ester, and polyoxyethylene glycerin fatty acid ester. Oxyethylene castor oil, hydrogenated castor oil, polyoxyethylene sorbitol fatty acid ester, polyethylene glycol fatty acid ester, fatty acid monoglyceride, polyglycerin fatty acid ester, sorbitan fatty acid ester, propylene glycol fatty acid ester, sucrose fatty acid ester, fatty acid alkanolamide, polyoxyethylene Fatty acid amide, polyoxyethylene alkylamine, alkylamine oxide, Ji glycol, acetylene alcohol, and the like.

  Among the surfactants, in order to improve the wettability to the printing substrate, it is preferable to use a surface tension adjuster, specifically, acetylene diol type, silicon type, acrylic type, and fluorine type are preferable. . The above surfactants may be used alone or in combination of two or more.

  Various additives such as a plasticizer, an ultraviolet ray inhibitor, a light stabilizer, an antioxidant, and a hydrolysis inhibitor can be used in the coating liquid and ink of the present invention.

<Printing method>
The coating and printed matter of the present invention can be obtained by forming or coating the coating liquid of the present invention on a substrate. Known wet film forming methods, for example, spin coating, casting, microgravure coating, gravure coating, bar coating, roll coating, wire bar coating, dip coating, spray coating, screen printing, It can be prepared by using a coating method such as a flexographic printing method, an offset printing method, an ink jet printing method, a capillary coating method, a nozzle coating method and the like.
Examples of the substrate include a glass plate and a resin plate.

  Among them, the ink jet printing method used in the present invention includes a single pass method in which the ink jet ink is ejected to the recording medium only once and performs recording, and a recording medium having a maximum recording width, which is perpendicular to the conveying direction of the recording medium. Any of a serial type in which recording is performed while reciprocally scanning a short shuttle head in the direction may be employed. Further, the ink jet recording apparatus needs to include an ink jet head (ink discharging means) for discharging the ink jet ink and a drying step for drying the ink discharged from the ink jet head. When the ink is ejected from the ink jet head, the ejected ink lands on the printing substrate and an image is recorded, and the image is transported in a drying device as the printing substrate is transported, and a drying process is performed. .

  The ink jet method is not particularly limited, and is a known method, for example, a charge control method for discharging ink using electrostatic attraction, a drop-on-demand method (pressure pulse method) using a vibration pressure of a piezo element, an electric signal. Acoustic ink jet system that emits ink using radiation pressure by irradiating the ink into an acoustic beam and using thermal radiation, and thermal ink jet (bubble jet (registered trademark)) that heats the ink to form bubbles and uses the generated pressure Any method may be used.

  The ink jet head used in the ink jet method may be of an on-demand type or a continuous type. In addition, the discharge method includes electro-mechanical conversion method (eg, single cavity type, double cavity type, bender type, piston type, share mode type, shared wall type, etc.), and electro-thermal conversion method (eg, thermal inkjet) Type, bubble jet (registered trademark) type, etc., electrostatic suction type (eg, electrolytic control type, slit jet type, etc.), and discharge type (eg, spark jet type, etc.). However, any discharge method may be used. There is no particular limitation on the ink nozzles and the like used for recording by the ink jet method, and they can be appropriately selected according to the purpose.

  The amount of ink droplets ejected from the inkjet head is preferably 0.2 to 20 picoliters (pL), and more preferably 1 to 15 picoliters (pL), from the viewpoint of a large drying load reduction effect and improvement in image quality. Is more preferred.

<Wavelength conversion film and color filter>
The wavelength conversion film and the color filter, which are one of the final forms of the present invention, absorb light from a light source, and when extracting light of a desired wavelength by fluorescence light generated by transmitted light or light absorption that has not been absorbed. What is used. In particular, when quantum dots are used in the present invention, fluorescence emission with an excellent quantum yield will be used. The wavelength conversion film of the present invention is obtained by applying the coating liquid or the ink composition of the present invention on a substrate, and contains a quantum dot that emits green and red fluorescent colors. A printing film is a planar member that mainly converts blue light of a light source into white light in a display panel or lighting, or adjusts pseudo white light or the like having an untuned color to a desired color.
Examples of the substrate include a glass plate and a resin plate.

  Further, the color filter of the present invention is a color filter obtained by forming at least one of the filter segments using the coating liquid or the ink composition of the present invention, and is particularly used for a liquid crystal display panel. Yes, specifically, three or more types of fine stripe filter segments of different hues are arranged in parallel or intersecting on the surface of a transparent substrate such as glass, or fine mosaic filter segments are arranged vertically and horizontally. It consists of those arranged in a fixed array. In the present invention, unlike a light absorption type color filter that extracts blue, green, and red light from a conventional white light source, green and red are extracted mainly by using a blue LED or the like as a light source and a fluorescent filter. When quantum dots are used, energy loss is reduced because fluorescence is extracted with a high quantum yield rather than light reduction due to light absorption, and a color with a narrow wavelength distribution and close to a pure color is obtained. Can be manufactured. Also, at this time, if a quantum dot that emits green and red fluorescence has a high absorbance in the blue light portion using the coating material of the present invention, it can be efficiently converted to fluorescence and the original blue light can be converted. Since the omission can be prevented, a filter having high color purity can be obtained without using a pigment or a light scattering substance that absorbs blue separately.

  In general, a color filter is often produced by a resist method of removing unnecessary portions by patterning exposure and development after producing a solid-coated thin film, and it is also applicable to the fine particle composition of the present invention. Although it is possible, it is advantageous to apply the inkjet method in the present invention from the viewpoint of productivity due to the difference in the number of steps and low cost in that there is no material loss in the developing step.

<Light emitting element>
Further, a light-emitting element having a light-emitting layer formed using a coating liquid or an ink composition, which is one of the final modes of the present invention, will be described in detail.

  The light-emitting element of the present invention is generally called an electroluminescent element, and is constituted by an element in which one or more organic layers are formed between an anode and a cathode. It refers to an element consisting of only a light emitting layer between the light emitting layer and the cathode. On the other hand, the multi-layer electroluminescent device is intended to facilitate the injection of holes and electrons into the light emitting layer in addition to the light emitting layer, and to facilitate the recombination of holes and electrons in the light emitting layer. For the purpose of doing so, it refers to a laminate of a hole injection layer, a hole transport layer, a hole blocking layer, an electron injection layer, and the like. Further, an interlayer which is adjacent to the light emitting layer between the light emitting layer and the anode and has a role of isolating the light emitting layer and the anode or the light emitting layer and the hole injection layer or the hole transport layer. Layers may be inserted. Therefore, typical device configurations of the multilayer electroluminescent device include (1) anode / hole injection layer / light emitting layer / cathode, and (2) anode / hole injection layer / hole transport layer / light emitting layer / cathode. (3) anode / hole injection layer / light emitting layer / electron injection layer / cathode, (4) anode / hole injection layer / hole transport layer / light emitting layer / electron injection layer / cathode, (5) anode / positive (6) anode / hole injection layer / hole transport layer / light emitting layer / hole blocking layer / electron injection layer / cathode; (7) anode / hole injection layer / hole blocking layer / electron injection layer / cathode Anode / light emitting layer / hole blocking layer / electron injection layer / cathode, (8) anode / light emitting layer / electron injection layer / cathode (9) anode / hole injection layer / hole transport layer / interlayer layer / light emitting layer / Cathode, (10) anode / hole injection layer / interlayer layer / emission layer / electron injection layer / cathode, (11) anode / hole injection layer / hole transport layer / inter Layer / light emitting layer / electron injection layer / cathode, an element formed by laminating a multilayer structure etc. can be considered.

  Each of the above-described layers may be formed of two or more layers, and some layers may be repeatedly laminated. As such an example, in recent years, an element configuration called “multi-photon emission” has been proposed in which some layers of the above-mentioned multilayer electroluminescent element are multilayered for the purpose of improving light extraction efficiency. For example, in an electroluminescent device composed of a glass substrate / anode / hole transporting layer / electron transporting light emitting layer / electron injection layer / charge generating layer / light emitting unit / cathode, the charge generating layer and the light emitting unit There is a method of laminating a plurality of portions.

For the hole injection layer, a hole injection material that exhibits an excellent hole injection effect with respect to the light emitting layer, and that can form a hole injection layer having excellent adhesion to the anode interface and excellent thin film formation properties is used. In the case where such materials are stacked in multiple layers and a material having a high hole-injection effect and a material having a high hole-transport effect are stacked in layers, the materials used for each are called a hole-injection material and a hole-transport material. Sometimes. The electroluminescent device material of the present invention can be suitably used as both a hole injection material and a hole transport material. These hole injection materials and hole transport materials need to have a high hole mobility and a small ionization energy of usually 5.5 eV or less. As such a hole injecting layer, a material that transports holes to the light emitting layer with a lower electric field strength is preferable, and the mobility of holes is, for example, at least when an electric field of 10 ⁴ to 10 ⁶ V / cm is applied. It is preferably 10 ⁻⁶ cm ² / V · sec. The other hole injecting material and hole transporting material that can be used by being mixed with the material for an electroluminescent element of the present invention are not particularly limited as long as they have the above preferable properties. In the conductive material, an arbitrary material can be selected from those commonly used as a hole charge transporting material and known materials used in a hole injection layer of an electroluminescent element.

  Specific examples of such a hole injection material and a hole transport material include, for example, a triazole derivative, an oxadiazole derivative, an imidazole derivative, a polyarylalkane derivative, a pyrazoline derivative and a pyrazolone derivative, a phenylenediamine derivative, and an arylamine derivative. , Amino-substituted chalcone derivatives, oxazole derivatives, styryl anthracene derivatives, fluorenone derivatives, hydrazone derivatives, stilbene derivatives, silazane derivatives, polysilane derivatives, aniline copolymers, conductive polymer oligomers (particularly thiophene oligomers) and the like. it can.

  Among them, porphyrin compounds, aromatic tertiary amine compounds and styrylamine compounds can be preferably used. For example, 4,4′-bis (N- (1-naphthyl) -N-phenylamino) biphenyl having two condensed aromatic rings in a molecule, and three triphenylamine units linked in a star burst type 4,4 ', 4 "-tris (N- (3-methylphenyl) -N-phenylamino) triphenylamine and the like. Further, as a hole injecting material, copper phthalocyanine, hydrogen phthalocyanine, or the like can be used. In addition, an inorganic compound such as an aromatic dimethylidene-based compound, p-type Si, or p-type SiC can also be used as a hole injection material or a hole transport material.

Further, materials usable for the hole injection layer include molybdenum oxide (MnO _x ), vanadium oxide (VO _x ), ruthenium oxide (RuO _x ), copper oxide (CuO _x ), tungsten oxide (WO _x ), and iridium oxide. Inorganic oxides such as (IrO _x ) are also included.

  In order to form the above-described hole injection layer, the above compound is thinned by a known method such as a vacuum evaporation method, a spin coating method, a casting method, and an LB method. The thickness of the hole injection layer is not particularly limited, but is usually 5 nm to 5 μm.

  Examples of the material used for the interlayer include polyvinyl carbazole and derivatives thereof, and polymers containing aromatic amines such as polyarylene derivatives having an aromatic amine in a side chain or a main chain, arylamine derivatives, and triphenyldiamine derivatives. In the case where a high molecular weight material is used, a method of forming a film from a solution is exemplified as a method of forming the interlayer.

  For forming an interlayer from a solution, a known wet film forming method, for example, a spin coating method, a casting method, a microgravure coating method, a gravure coating method, a bar coating method, a roll coating method, a wire bar coating method, Coating methods such as dip coating, spray coating, screen printing, flexographic printing, offset printing, inkjet printing, capillary coating, and nozzle coating can be used.

  The thickness of the interlayer is optimally different depending on the material used, and may be selected so that the driving voltage and the luminous efficiency have appropriate values. Usually, the thickness is 1 nm to 1 μm, and preferably 2 to 500 nm. More preferably, it is 5 to 200 nm.

  On the other hand, for the electron injection layer, an electron injection material that exhibits an excellent electron injection effect with respect to the light emitting layer, and that can form an electron injection layer having excellent adhesion to the cathode interface and excellent thin film formation properties is used. Examples of such electron injecting materials include metal complex compounds, nitrogen-containing five-membered ring derivatives, fluorenone derivatives, anthraquinodimethane derivatives, diphenoquinone derivatives, thiopyrandioxide derivatives, perylenetetracarboxylic acid derivatives, fluorenylidenemethane Derivatives, anthrone derivatives, silole derivatives, triarylphosphine oxide derivatives, polyquinolines and derivatives thereof, polyquinoxalines and derivatives thereof, polyfluorenes and derivatives thereof, calcium acetylacetonate, sodium acetate and the like. Also, an inorganic / organic composite material obtained by doping a metal such as cesium into bathophenanthroline, and a proceedings of the 50th Federation of Applied Physics-related lectures; 3, 1402, BCP, TPP, T5MPyTZ, etc., published in 2003, are also examples of electron injecting materials. However, a thin film necessary for device fabrication can be formed, electrons can be injected from a cathode, and electrons can be transported. The material is not particularly limited as long as it is a material.

  Preferred examples of the electron injecting material include a metal complex compound, a nitrogen-containing five-membered ring derivative, a silole derivative, and a triarylphosphine oxide derivative. As a preferable metal complex compound usable in the present invention, a metal complex of 8-hydroxyquinoline or a derivative thereof is suitable. Specific examples of the metal complex of 8-hydroxyquinoline or a derivative thereof include tris (8-hydroxyquinolinato) aluminum, tris (2-methyl-8-hydroxyquinolinato) aluminum, tris (4-methyl-8- (Hydroxyquinolinato) aluminum, tris (5-methyl-8-hydroxyquinolinato) aluminum, tris (5-phenyl-8-hydroxyquinolinato) aluminum, bis (8-hydroxyquinolinato) (1-naphtholate) ) Aluminum, bis (8-hydroxyquinolinato) (2-naphtholate) aluminum, bis (8-hydroxyquinolinato) (phenolate) aluminum, bis (8-hydroxyquinolinato) (4-cyano-1-naphtholate) ) Aluminum, bis (4-methyl-8-) Droxyquinolinato) (1-naphtholate) aluminum, bis (5-methyl-8-hydroxyquinolinato) (2-naphtholate) aluminum, bis (5-phenyl-8-hydroxyquinolinato) (phenolate) aluminum, Bis (5-cyano-8-hydroxyquinolinato) (4-cyano-1-naphtholate) aluminum, bis (8-hydroxyquinolinato) chloroaluminum, bis (8-hydroxyquinolinato) (o-cresolate) Aluminum complex compounds such as aluminum, tris (8-hydroxyquinolinato) gallium, tris (2-methyl-8-hydroxyquinolinato) gallium, tris (4-methyl-8-hydroxyquinolinato) gallium, tris ( 5-methyl-8-hydroxyquinolinate) Lium, tris (2-methyl-5-phenyl-8-hydroxyquinolinate) gallium, bis (2-methyl-8-hydroxyquinolinate) (1-naphtholate) gallium, bis (2-methyl-8-hydroxy) Quinolinato) (2-naphtholate) gallium, bis (2-methyl-8-hydroxyquinolinato) (phenolate) gallium, bis (2-methyl-8-hydroxyquinolinate) (4-cyano-1-naphtholate) Gallium, bis (2,4-dimethyl-8-hydroxyquinolinate) (1-naphtholate) gallium, bis (2,5-dimethyl-8-hydroxyquinolinate) (2-naphtholate) gallium, bis (2 -Methyl-5-phenyl-8-hydroxyquinolinato) (phenolate) gallium, bis (2-methyl-5-cy Ano-8-hydroxyquinolinate) (4-cyano-1-naphtholate) gallium, bis (2-methyl-8-hydroxyquinolinate) chlorogallium, bis (2-methyl-8-hydroxyquinolinate) ( In addition to gallium complex compounds such as (o-cresolate) gallium, lithium 8-hydroxyquinolinato, bis (8-hydroxyquinolinato) copper, bis (8-hydroxyquinolinato) manganese, bis (10-hydroxybenzo [h ] Quinolinato) beryllium, bis (8-hydroxyquinolinato) zinc, metal complex compounds such as bis (10-hydroxybenzo [h] quinolinato) zinc.

  Among the electron injecting materials that can be used in the present invention, preferred nitrogen-containing five-membered ring derivatives include oxazole derivatives, thiazole derivatives, oxadiazole derivatives, thiadiazole derivatives, and triazole derivatives. , 5-bis (1-phenyl) -1,3,4-oxazole, 2,5-bis (1-phenyl) -1,3,4-thiazole, 2,5-bis (1-phenyl) -1, 3,4-oxadiazole, 2- (4′-tert-butylphenyl) -5- (4 ″ -biphenyl) 1,3,4-oxadiazole, 2,5-bis (1-naphthyl) -1 , 3,4-oxadiazole, 1,4-bis [2- (5-phenyloxadiazolyl)] benzene, 1,4-bis [2- (5-phenyloxadiazolyl) -4-tert-butyl benzene], 2- (4′-tert-butylphenyl) -5- (4 ″ -biphenyl) -1,3,4-thiadiazole, 2,5-bis (1-naphthyl) -1,3,4-thiadiazole, 1, 4-bis [2- (5-phenylthiadiazolyl)] benzene, 2- (4′-tert-butylphenyl) -5- (4 ″ -biphenyl) -1,3,4-triazole, 2,5- Bis (1-naphthyl) -1,3,4-triazole, 1,4-bis [2- (5-phenyltriazolyl)] benzene and the like can be mentioned.

Further, examples of a material that can be used for the electron injection layer include inorganic oxides such as zinc oxide (ZnO) and titanium oxide (TiO ₂ ).

  Further, the hole blocking layer is made of a hole blocking material that prevents holes passing through the light emitting layer from reaching the electron injection layer and can form a layer having excellent thin film forming properties. Examples of such a hole blocking material include aluminum complex compounds such as bis (8-hydroxyquinolinato) (4-phenylphenolate) aluminum and bis (2-methyl-8-hydroxyquinolinate) ( Gallium complex compounds such as (4-phenylphenolate) gallium; and nitrogen-containing condensed aromatic compounds such as 2,9-dimethyl-4,7-diphenyl-1,10-phenanthroline (BCP).

As the light emitting layer of the electroluminescent device of the present invention, those having the following functions are suitable.
Injection function; Capability of injecting holes from the anode or hole injection layer and injecting electrons from the cathode or electron injection layer when applying an electric field Transport function; Transfer of injected charges (electrons and holes) to the electric field The function of moving by the force of light; the function of providing a field of recombination of electrons and holes, and the function of connecting it to light emission. However, there is a difference between the ease of hole injection and the ease of electron injection. And the transport capacity represented by the mobility of holes and electrons may be large or small.

  The light emitting layer formed using the coating liquid or the ink composition of the present invention can be suitably used. Forming a light-emitting layer by combining the coating liquid or ink composition of the present invention with another light-emitting compound in order to obtain a light-emitting layer formed using the coating liquid or the ink composition of the present invention. Can be.

  In order to obtain a light emitting layer formed using the coating liquid or the ink composition of the present invention, it may be added to the coating liquid or the ink composition of the present invention, as a compound that emits blue to green light. For example, benzothiazole-based, benzimidazole-based, benzoxazole-based fluorescent brighteners, metal-chelated oxinoid compounds, and styrylbenzene-based compounds can be used.

  Preferred examples of the metal chelated oxinoid compound include 8-hydroxyquinoline-based metal complexes such as tris (8-quinolinol) aluminum and dilithium epthridione.

  Further, as the styrylbenzene-based compound, for example, a distyrylpyrazine derivative can also be used as a material for the light emitting layer. In addition, a polyphenyl compound may be added to the coating liquid or the ink composition of the present invention.

  Further, in addition to the above-described fluorescent whitening agent, metal chelated oxinoid compound, styrylbenzene-based compound, and the like, for example, 12-phthaloperinone, 1,4-diphenyl-1,3-butadiene, 1,1,4,4-tetraphenyl -1,3-butadiene, naphthalimide derivative, perylene derivative, oxadiazole derivative, aldazine derivative, pyrazin derivative, cyclopentadiene derivative, pyrrolopyrrole derivative, styrylamine derivative, coumarin compound, polymer compound, 9,9 ′, Examples thereof include 10,10′-tetraphenyl-2,2′-bianthracene, PPV (polyparaphenylene vinylene) derivatives, polyfluorene derivatives, and copolymers thereof. Phenolate ligands such as bis (2-methyl-8-quinolinolate) (para-phenylphenolate) aluminum (III) and bis (2-methyl-8-quinolinolate) (1-naphtholate) aluminum (III); Metal complexes having a substituted 8-quinolinolate ligand simultaneously are mentioned.

  The light emitting layer for emitting white light is not particularly limited, but the following can be used. One in which the energy level of each layer of the electroluminescent laminated structure is specified and light is emitted by utilizing tunnel injection (EP 0390551). Similarly, a white light-emitting element is described as an example of an element utilizing tunnel injection (Japanese Patent Application Laid-Open No. 3-230584). One in which a light emitting layer having a two-layer structure is described (JP-A-2-220390 and JP-A-2-216790). The light-emitting layer is divided into a plurality of light-emitting layers, each of which is made of a material having a different emission wavelength (Japanese Patent Laid-Open No. 4-51491). A structure in which a blue light emitter (fluorescence peak: 380 to 480 nm) and a green light emitter (480 to 580 nm) are laminated, and a red phosphor is further contained (Japanese Patent Laid-Open No. 6-207170). A structure in which a blue light-emitting layer contains a blue fluorescent dye, a green light-emitting layer has a region containing a red fluorescent dye, and further contains a green phosphor (Japanese Patent Application Laid-Open No. 7-142169).

Further, as the material used for the anode of the electroluminescent device of the present invention, a material having a large work function (4 eV or more), a metal, an alloy, an electrically conductive compound, or a mixture thereof is preferably used. Specific examples of such an electrode material include metals such as Au, and conductive materials such as CuI, ITO, SnO ₂ , and ZnO. In order to form this anode, a thin film can be formed from these electrode substances by a method such as an evaporation method or a sputtering method. The anode desirably has such a property that, when light emitted from the light emitting layer is extracted from the anode, the transmittance of the anode to the emitted light is greater than 10%. Further, the sheet resistance of the anode is preferably several hundred Ω / □ or less. Further, the thickness of the anode is selected in the range of usually 10 nm to 1 μm, preferably 10 to 200 nm, although it depends on the material.

  Further, as a material used for the cathode of the electroluminescent device of the present invention, a metal, an alloy, an electrically conductive compound having a low work function (4 eV or less), and a mixture thereof are used as an electrode material. Specific examples of such an electrode material include sodium, sodium-potassium alloy, magnesium, lithium, magnesium-silver alloy, aluminum / aluminum oxide, aluminum-lithium alloy, indium, and rare earth metals. This cathode can be manufactured by forming a thin film from these electrode substances by a method such as vapor deposition or sputtering. Here, when the light emitted from the light emitting layer is taken out from the cathode, it is preferable that the transmittance of the cathode with respect to the emitted light be greater than 10%. Further, the sheet resistance as the cathode is preferably several hundred Ω / □ or less, and the film thickness is usually 10 nm to 1 μm, preferably 50 to 200 nm.

  With respect to the method of manufacturing the electroluminescent device of the present invention, the anode and the light emitting layer, the hole injection layer as needed, and the electron injection layer as needed are formed by the above-mentioned materials and the method, and finally the cathode is formed. do it. In addition, an electroluminescent element can be manufactured in the reverse order from the cathode to the anode.

  This electroluminescent element is manufactured over a light-transmitting substrate. The light-transmitting substrate is a substrate that supports the electroluminescent element. The light-transmitting substrate preferably has a light transmittance of 50% or more, preferably 90% or more in the visible region of 400 to 700 nm. It is preferable to use a smoother substrate.

  These substrates are not particularly limited as long as they have mechanical and thermal strength and are transparent. For example, a glass plate, a synthetic resin plate, or the like is preferably used. Examples of the glass plate include a plate formed of soda lime glass, barium / strontium-containing glass, lead glass, aluminosilicate glass, borosilicate glass, barium borosilicate glass, quartz, or the like. Examples of the synthetic resin plate include plates made of polycarbonate resin, acrylic resin, polyethylene terephthalate resin, polyether sulfide resin, polysulfone resin, and the like.

  Examples of the method for forming each layer except for the light emitting layer of the electroluminescent device of the present invention include vacuum deposition, electron beam irradiation, sputtering, plasma, dry film forming methods such as ion plating, or spin coating, dipping, flow coating, and the like. Any of the wet film forming methods can be applied. In addition, Japanese Patent Application Laid-Open No. 2002-534784 and S.I. T. Lee, et al. , Proceedings of SID '02, p. 784 (2002), a laser induced thermal imaging (LITI) method, a printing method (offset printing, flexographic printing, gravure printing, screen printing), an ink jet method, and the like.

  The organic layer excluding the polymer material is particularly preferably a molecular deposition film. Here, the molecular deposition film refers to a thin film formed by deposition from a material compound in a gaseous state or a film formed by solidification from a material compound in a solution state or a liquid phase state. Can be distinguished from a thin film (molecule accumulation film) formed by the LB method by a difference in an aggregated structure and a higher-order structure and a functional difference caused by the difference. Further, as disclosed in JP-A-57-51781, a binder and a material compound such as a resin are dissolved in a solvent to form a solution, which is then formed into a thin film by spin coating or the like. An organic layer can be formed. The thickness of each layer is not particularly limited. However, if the thickness is too large, a large applied voltage is required to obtain a constant light output, resulting in poor efficiency. Are generated, and it becomes difficult to obtain sufficient light emission luminance even when an electric field is applied. Therefore, the thickness of each layer is suitably in the range of 1 nm to 1 μm, but is more preferably in the range of 10 nm to 0.2 μm.

  In order to improve the stability of the electroluminescent device against temperature, humidity, atmosphere, and the like, a protective layer may be provided on the surface of the device, or the entire device may be covered or sealed with a resin or the like. In particular, when covering or sealing the entire device, a photocurable resin that is cured by light is preferably used.

  The current applied to the electroluminescent device of the present invention is usually a direct current, but a pulse current or an alternating current may be used. The current value and the voltage value are not particularly limited as long as they are within a range in which the element is not destroyed. However, considering the power consumption and the life of the element, it is desirable to emit light efficiently with as little electric energy as possible.

  The driving method of the electroluminescent device of the present invention can be driven not only by the passive matrix method but also by the active matrix method. In addition, as a method of extracting light from the electroluminescent device of the present invention, not only a method of bottom emission for extracting light from the anode side but also a method of top emission for extracting light from the cathode side is applicable. These methods and techniques are described in Junji Kido, "All about Electroluminescence", published by Nihon Jitsugyo Shuppan (2003).

  The main methods of the full-color electroluminescent device of the present invention include a three-color coating method, a color conversion method, and a color filter method. Examples of the three-color coating method include an evaporation method using a shadow mask, an ink jet method, and a printing method. In addition, Japanese Patent Application Laid-Open No. 2002-534784 and S.I. T. Lee, et al. , Proceedings of SID '02, p. 784 (2002), which is also referred to as Laser Induced Thermal Imaging (LITI). In the color conversion method, a blue light-emitting layer is used to convert green and red wavelengths longer than blue through a color conversion (CCM) layer in which a fluorescent dye is dispersed. The color filter method is a method of extracting light of three primary colors through a color filter for liquid crystal using a white light emitting electroluminescent element. In addition to these three primary colors, a part of white light is directly extracted and used for light emission. Thus, the luminous efficiency of the entire device can be increased.

  Further, the electroluminescent device of the present invention may employ a microcavity structure. The electroluminescent device has a structure in which a light emitting layer is sandwiched between an anode and a cathode, and emitted light causes multiple interference between the anode and the cathode. By appropriately selecting the optical characteristics such as the ratio and the thickness of the organic layer sandwiched between them, the multiple interference effect is actively used to control the emission wavelength extracted from the element. . Thereby, the emission chromaticity can be improved. The mechanism of this multiple interference effect is described in AM-LCD Digest of Technical Papers, OD-2, p. 77-80 (2002).

  As described above, the electroluminescent device using the light emitting layer formed using the coating liquid or the ink composition of the present invention can emit light for a long time at a low driving voltage. Therefore, the present electroluminescent device can be used as a flat panel display such as a wall-mounted television and various kinds of flat light emitters, and further, a light source such as a copier and a printer, a light source such as a liquid crystal display and instruments, a display board, and a sign lamp. The application of is considered.

  Hereinafter, the present invention will be described specifically with reference to examples, but the present invention is not particularly limited to the examples. In Examples, “parts” and “%” represent “parts by mass” and “% by mass”.

<Preparation of semiconductor fine particle (quantum dot) composition>
[Example 1] (Quantum dot dispersion liquid QD-1)
QD: InP / ZnS core-shell quantum dots were synthesized as follows in accordance with the description in the technical document “Inorganic Chemistry 2016, (17), pp8381-8386”.
0.22 parts of indium chloride and 8.25 parts of octylamine were placed in a reaction vessel and heated to 180 ° C. while performing nitrogen bubbling. After the indium chloride was dissolved, 0.86 parts of diethylaminophosphine was injected in a short time, and the temperature was controlled at 180 ° C. for 20 minutes. Thereafter, it was rapidly cooled to 40 ° C. Separately, 0.55 part of anhydrous zinc acetate and an additive solution obtained by heating and dissolving 15.0 parts of the compound (58) shown in Table 6 were injected, and the mixture was heated at 220 ° C. for 5 hours and then allowed to cool to room temperature. After allowing to cool, purification was performed by a reprecipitation method using hexane and ethanol. Further, the solid content concentration was adjusted to 10% using toluene, and a quantum dot dispersion liquid QD-1 surface-coated with the compound (58) was obtained.

[Comparative Example 1] (Quantum dot dispersion liquid QD-2)
0.22 parts of indium chloride and 8.25 parts of octylamine were placed in a reaction vessel and heated to 165 ° C. while performing nitrogen bubbling. After the indium chloride was dissolved, 0.86 parts of diethylaminophosphine was injected in a short time, and the temperature was controlled at 165 ° C for 20 minutes. Thereafter, it was rapidly cooled to 40 ° C. Separately, an additive solution obtained by heating and dissolving 0.55 part of anhydrous zinc acetate, 7.0 parts of dodecanethiol, and 5.0 parts of oleylamine was injected, heated at 240 ° C. for 2 hours, and allowed to cool to room temperature. After allowing to cool, purification was performed by a reprecipitation method using hexane and ethanol. Further, the solid content concentration was adjusted to 10% using toluene, and a quantum dot dispersion liquid QD-2 surface-treated with dodecanethiol (C-1) was obtained.

[Example 2] (Quantum dot dispersion liquid QD-3)
The obtained dispersion liquid QD-2 was further diluted to a solid concentration of 1% using toluene. A 5% toluene solution of the compound (2) shown in Table 1 was prepared, added in the same amount, and stirred for 12 hours. Purification was performed by a reprecipitation method using hexane and ethanol. The solid content concentration was adjusted to 10% using trimethylbenzene, and a quantum dot dispersion QD-3 surface-coated with the compound (2) was obtained.

[Examples 3 to 10] (Quantum dot dispersion liquids QD-4 to QD-11)
Compound (2), which is a surface coating treatment agent of the dispersion QD-3, was changed to a coating material shown in Table 7 (compounds shown in Tables 1 to 6), and subjected to a surface coating treatment. By performing the preparation, quantum dot dispersions QD-4 to QD-11 surface-coated with the respective compounds of the present invention were obtained.

[Comparative Example 2] (Quantum dot dispersion liquid QD-12)
0.22 parts of indium chloride and 8.25 parts of octylamine were placed in a reaction vessel and heated to 165 ° C. while performing nitrogen bubbling. After the indium chloride was dissolved, 0.86 parts of diethylaminophosphine was injected in a short time, and the temperature was controlled at 165 ° C for 20 minutes. Thereafter, it was rapidly cooled to 40 ° C. Separately, an additive solution obtained by heating and dissolving 0.55 parts of anhydrous zinc acetate and 15.0 parts of 3,6,9,12-tetraoxadecaneamine was injected, heated at 240 ° C. for 2 hours, and then allowed to cool to room temperature. . After allowing to cool, purification was performed by a reprecipitation method using hexane and ethanol. Further, a quantum dot dispersion QD prepared by using 2-acetoxy-1-methoxypropane to a solid concentration of 10% and surface-coated with 3,6,9,12-tetraoxadecaneamine (C-2) is used. -12 was obtained.

[Examples 11 to 14] (Quantum dot dispersion liquids QD-13 to QD-16)
The obtained dispersion QD-12 was further diluted to a solid concentration of 1% using 2-acetoxy-1-methoxypropane. 5% 2-acetoxy-1-methoxypropane solutions of the coating materials described in Table 7 (the compounds described in Tables 1 to 6) were respectively prepared and added in the same amount, followed by stirring for 12 hours. Purification was performed by a reprecipitation method using hexane and ethanol. The solid content concentration was adjusted to 10% using 2-acetoxy-1-methoxypropane, and quantum dot dispersions QD-13 to QD-16 surface-treated with the respective compounds of the present invention were obtained.

<Preparation of resin solution>
(Resin solution 1)
Paraffin wax 155 (manufactured by Nippon Seiro) was dissolved in decane so as to have an NV of 10% to prepare a resin solution 1.

(Resin solution 2)
A reaction vessel equipped with a thermometer, a cooling pipe, a nitrogen gas introduction pipe, and a stirrer in a separable four-necked flask was charged with 70.0 parts of xylene, the temperature was raised to 80 ° C., and the inside of the reaction vessel was purged with nitrogen. A mixture of 18.0 parts of n-butyl methacrylate, 12.0 parts of methyl methacrylate, and 0.4 part of 2,2′-azobisisobutyronitrile was added dropwise over 2 hours. After completion of the dropwise addition, the reaction was further continued for 3 hours to obtain a solution of an acrylic resin having a mass average molecular weight (Mw) of 26,000. After cooling to room temperature, about 2 g of the resin solution was sampled, heated and dried at 180 ° C. for 20 minutes to measure the nonvolatile content, and xylene was added to the previously synthesized resin solution so that the nonvolatile content was 20% by mass. Thus, a resin solution 2 was prepared.

<Preparation of inkjet ink>
[Examples 1 to 14, Comparative Examples 1 and 2]
In the container having the composition shown in Table 7, the quantum dot dispersion liquid, the resin solution, and the solvent were weighed in a sealable container in this order, and then sealed and shaken for 3 minutes to prepare an inkjet ink.

<Evaluation of inkjet ink>
[viscosity]
The viscosity of the inkjet ink was measured at 25 ° C. using a vibration type viscometer Viscomate VM-10AL (manufactured by SEKONIC).

[Ink appearance]
The obtained ink-jet ink was visually evaluated for the appearance of the ink according to the following criteria. In the case of Δ to ×, ink cannot be prepared.
：: Transparent state without turbidity of ink appearance (usable)
△: cloudy (cannot be used)
×: Deposits formed (cannot be used)

[Dischargeability]
The obtained inkjet ink was printed under the following conditions, and the dischargeability was evaluated based on the following criteria.
：: Discharged according to print pattern (good)
○ △: Slight abnormalities in re-discharge after discharge interruption (usable)
Δ: Nozzle clogging etc. gradually occurred during continuous discharge (cannot be used)
×: An abnormality such as nozzle clogging from the beginning (cannot be used)
≪Inkjet discharge test conditions≫
Printing machine: DimatixMaterialsPrinter
Cartridges: 10 Dimatix Materials Cartridges, 10 pL
Print pattern: Lattice pattern at 1mm interval Substrate: Round cover glass, manufactured by Matsunami Glass Industry Substrate temperature: 30 ° C
Drying after printing: 40 ° C for 20 minutes

[Print appearance]
The printed matter obtained in the ejection test was evaluated for the appearance of the printed matter according to the following criteria.
：: When the image conforms to the printed pattern of the printed matter appearance (good)
○ △: When fading is observed (usable)
Δ: When the image is distorted (cannot be used)
×: When adhered without trace of print pattern (cannot be used)

[Quantum yield measurement]
The quantum yield of the obtained inkjet ink was measured under the following conditions. The QY maintenance ratio is a ratio after 4 weeks, where the quantum efficiency (hereinafter, also referred to as QY) at the beginning of printing is 1.
Measurement device: Otsuka Electronics Co., Ltd. QE-2000
Excitation wavelength: 400 nm, integration range: 375-425 nm
Fluorescence integration range: 430-800 nm

  It was confirmed that, when the inkjet ink of the present invention was used, inkjet printing was possible and printing was possible with a high quantum yield. It is assumed that coating materials and printed materials produced by other coating methods and printing methods using other coating liquids and inks have almost the same characteristics, and wavelength conversion films and color filters using these are expected to have the desired performance. It was shown that can be exhibited.

<Preparation of semiconductor fine particle (quantum dot) composition for electroluminescent device>
[Examples 29 to 33] (Quantum dot dispersion liquids QD-17 to QD-21)
As a quantum dot dispersion for an electroluminescent device, the dispersion QD-2 was further diluted to a solid content concentration of 1% using toluene. 5% toluene solutions of the compounds (1), (39) and (51) described in Tables 1 to 6 were respectively prepared, added in the same amounts, and stirred for 12 hours. Purification was performed by a reprecipitation method using hexane and ethanol. The solid content concentration was adjusted to 10% using trimethylbenzene, and quantum dot dispersions QD-17 to QD-19 each of which was surface-coated with compound (1), (39) or (51) were obtained. Further, the dispersion QD-16 was further diluted to a solid concentration of 1% using 2-acetoxy-1-methoxypropane. A 5% 2-acetoxy-1-methoxypropane solution of the compound (50) or (59) in Table 1 was prepared, added in the same amount, and stirred for 12 hours. Purification was performed by a reprecipitation method using hexane and ethanol. Using 2-acetoxy-1-methoxypropane, the solid content concentration was adjusted to 10%, and quantum dot dispersions QD-20 and QD-21 surface-coated with compound (50) or (59), respectively, were obtained. .

<Preparation of electroluminescent element>
An electroluminescent device was prepared as described below. In the examples, all mixing ratios indicate mass ratios, unless otherwise specified. The vapor deposition (vacuum vapor deposition) was performed in a vacuum of 10 ⁻⁶ Torr without any temperature control such as heating and cooling of the substrate. The light emission characteristics of the element were measured using an electroluminescent element having a light emitting element area of 2 mm x 2 mm.
≪Inkjet discharge test conditions≫
Printing machine: DimatixMaterialsPrinter
Cartridges: 10 Dimatix Materials Cartridges, 10 pL
Print pattern: solid print pattern (1.2 cm x 1.2 cm area with a total of 6 2 mm x 2 mm elements)
Substrate temperature: 30 ° C
Drying after printing: 40 ° C for 20 minutes

[Example 34]
In a sealable container, 1 part of the quantum dot dispersion liquid QD-1, 1 part of the resin solution 1, and 30 parts of trimethylbenzene as a solvent are weighed in this order, and then sealed and shaken for 3 minutes. To prepare the inkjet ink.
PEDOT / PSS (poly (3,4-ethylenedioxy) -2,5-thiophene / polystyrene sulfonic acid, CLEVIUS (registered trademark) PVP CH8000 manufactured by Heraeus) is spin-coated on a washed glass plate with an ITO electrode. And dried at 110 ° C. for 20 minutes to obtain a hole injection layer having a thickness of 35 nm. Next, poly (N-vinylcarbazole) is dissolved in monochlorobenzene at a concentration of 1.0% by mass, formed into a film by spin coating, dried at 110 ° C. for 20 minutes, and transported with a hole thickness of 35 nm. A layer was formed. Using the prepared ink-jet ink, ink-jet printing was performed under the above-described discharge conditions to form a light-emitting layer having a thickness of 20 nm. A zinc oxide isopropanol dispersion N-10 manufactured by Avantama was formed thereon by spin coating to form an 80 nm electron transport layer. Finally, 200 nm of aluminum (Al) was vapor-deposited to form an electrode, and an electroluminescent device was obtained.
This device exhibited red light emission with an external quantum efficiency of 5.0% and an emission luminance of 32000 (cd / m ² ) at 8 V, a peak wavelength of an emission spectrum of 655 nm, and a full width at half maximum of 52 nm. When the device was driven at a constant current at room temperature at a light emission luminance of 1000 (cd / m ² ), the luminance half life was 1000 hours or more. The luminous efficiency when driven at a current density of 10 (mA / cm ² ) was 6.3 (cd / A), and the relative luminance after continuous driving in an environment of 80 ° C. for 100 hours (= (100 hours) (Later luminance) / (initial luminance)) was 0.86.

[Example 35]
In a container that can be sealed, 1 part of the quantum dot dispersion liquid QD-6, 1 part of the resin solution 2, and 30 parts of trimethylbenzene as a solvent are weighed in this order, and then sealed and shaken for 3 minutes. To produce an ink jet ink.
Each layer was formed in the same manner as in Example 34 except that a light-emitting layer was formed by changing this to the ink-jet ink of Example 34, and an electroluminescent element was obtained. About the obtained electroluminescent element, evaluation of external quantum efficiency etc. was performed like Example 34.

[Example 36]
In a container that can be sealed, 1 part of the quantum dot dispersion liquid QD-10, 1 part of the resin solution 2, and 30 parts of trimethylbenzene as a solvent are weighed in this order, and then sealed and shaken for 3 minutes. To produce an ink jet ink.
Each layer was formed in the same manner as in Example 34 except that a light-emitting layer was formed by changing this to the ink-jet ink of Example 34, and an electroluminescent element was obtained. About the obtained electroluminescent element, evaluation of external quantum efficiency etc. was performed like Example 34.

[Example 37]
In a sealable container, 1 part of the quantum dot dispersion liquid QD-15, 1 part of the resin solution 2, and then 30 parts of 2-acetoxy-1-methoxypropane as a solvent were weighed in this order, and then sealed, Shaking was performed for 3 minutes to produce an ink jet ink.
Each layer was formed in the same manner as in Example 34 except that a light-emitting layer was formed by changing this to the ink-jet ink of Example 34, and an electroluminescent element was obtained. About the obtained electroluminescent element, evaluation of external quantum efficiency etc. was performed like Example 34.

[Example 38]
In a container that can be sealed, 1 part of the quantum dot dispersion liquid QD-17, 1 part of the resin solution 2, and then 30 parts of trimethylbenzene as a solvent are weighed in this order, and then sealed and shaken for 3 minutes. To produce an ink jet ink.
Each layer was formed in the same manner as in Example 34 except that a light-emitting layer was formed by changing this to the ink-jet ink of Example 34, and an electroluminescent element was obtained. About the obtained electroluminescent element, evaluation of external quantum efficiency etc. was performed like Example 34.

[Example 39]
In a sealable container, 1 part of the quantum dot dispersion liquid QD-18, 1 part of the resin solution 2, and then 30 parts of trimethylbenzene as a solvent are weighed in this order, and then sealed and shaken for 3 minutes. To produce an ink jet ink.
Each layer was formed in the same manner as in Example 34 except that a light-emitting layer was formed by changing this to the ink-jet ink of Example 34, and an electroluminescent element was obtained. About the obtained electroluminescent element, evaluation of external quantum efficiency etc. was performed like Example 34.

[Example 40]
In a container that can be sealed, 1 part of the quantum dot dispersion liquid QD-19, 1 part of the resin solution 2, and then 30 parts of trimethylbenzene as a solvent are weighed in this order, and then sealed and shaken for 3 minutes. To produce an ink jet ink.
Each layer was formed in the same manner as in Example 34 except that a light-emitting layer was formed by changing this to the ink-jet ink of Example 34, and an electroluminescent element was obtained. This device emitted green light with an external quantum efficiency of 7.2% and an emission luminance of 56000 (cd / m ² ) at 8 V. The peak wavelength of the emission spectrum was 547 nm, and the full width at half maximum was 37 nm. About the obtained electroluminescent element, evaluation of external quantum efficiency etc. was performed like Example 34.

[Example 41]
In a container that can be sealed, 1 part of the quantum dot dispersion liquid QD-20, 1 part of the resin solution 2, and then 30 parts of 2-acetoxy-1-methoxypropane as a solvent are weighed in this order, and then sealed, Shaking was performed for 3 minutes to produce an ink jet ink.
Each layer was formed in the same manner as in Example 34 except that a light-emitting layer was formed by changing this to the ink-jet ink of Example 34, and an electroluminescent element was obtained. About the obtained electroluminescent element, evaluation of external quantum efficiency etc. was performed like Example 34.

[Example 42]
In a container that can be sealed, 1 part of the quantum dot dispersion liquid QD-21, 1 part of the resin solution 2, and then 30 parts of 2-acetoxy-1-methoxypropane as a solvent are weighed in this order, and then sealed, Shaking was performed for 3 minutes to produce an ink jet ink.
Each layer was formed in the same manner as in Example 34 except that a light-emitting layer was formed by changing this to the ink-jet ink of Example 34, and an electroluminescent element was obtained. About the obtained electroluminescent element, evaluation of external quantum efficiency etc. was performed like Example 34.

[Comparative Example 5]
In a sealable container, 1 part of the quantum dot dispersion liquid QD-12, 1 part of the resin solution 2, and then 30 parts of 2-acetoxy-1-methoxypropane as a solvent were weighed in this order, and then sealed, Shaking was performed for 3 minutes to produce an ink jet ink.
Each layer was formed in the same manner as in Example 34 except that a light-emitting layer was formed by changing this to the ink-jet ink of Example 34, and an electroluminescent element was obtained. About the obtained electroluminescent element, evaluation of external quantum efficiency etc. was performed like Example 34.

<Evaluation of electroluminescent element>
Table 10 shows the evaluation results of the obtained electroluminescent devices.

By producing a light emitting device using an inkjet ink comprising the semiconductor fine particle composition of the present invention, a device having excellent light emitting characteristics and stability could be produced. It is presumed that excellent characteristics can be exhibited also in light emitting devices manufactured by other coating methods and printing methods using other coating liquids and inks.

Claims (16)

A semiconductor fine particle composition comprising semiconductor fine particles and a coating material covering the surface of the particles, wherein the coating material has a structure represented by the following general formula (1) or general formula (2).
General formula (1)
General formula (2)
[In the general formulas (1) and (2),
X ^{1 to} X ⁴ are each independently N, S, O, NR ¹ , NR ² R ³ , OR ⁴ or SR ⁵ ;
Y ^{1 to} Y ⁵ are each independently C or N;
R ^{1 to} R ⁵ are each independently a hydrogen atom or a monovalent alkyl group which may have a substituent.
X ¹ Y ¹ Y ² X ² and X ³ Y ³ Y ⁴ Y ⁵ X ⁴ are π-conjugated,
X ^{1 to} X ⁴ and Y ^{1 to} Y ⁵ may form a ring structure Ar ^{1 to} Ar ⁷ containing adjacent groups,
When forming the ring structures Ar ^{1 to} Ar ⁷ ,
Ar ^{1 to} Ar ⁷ are each independently a divalent π-conjugated unit which may have a substituent,
X ¹ is a constituent atomic group of Ar ¹ or a group directly bonded to Ar ² ;
X ² is a constituent atomic group of Ar ³ or a group directly bonded to Ar ² ;
X ³ is a constituent atomic group of Ar ⁴ or a group directly bonded to Ar ⁵ ;
X ⁴ is a constituent atomic group of Ar ⁷ or a group directly bonded to Ar ⁶ . ] Any two or more of Ar ^{1 to} Ar ^{3 in} the general formula (1) or Ar ^{4 to} Ar ^{7 in} the general formula (2) may be formed by condensing adjacent π-conjugated units with each other. The semiconductor fine particle composition according to claim 1, wherein the composition is a 5- or 6-membered aromatic ring that may have. 3. The semiconductor fine particle composition according to claim 1, wherein X ^{1 to} X ⁴ in the general formulas (1) and (2) are each independently N or OR ^{4. 4} .   At least one ring selected from the group consisting of an 8-hydroxyquinoline ring, a benzoxazole ring, a benzothiazole ring, a benzoimidazole ring, a benzotriazole ring, and a triazine ring, wherein the coating material may have a substituent; The semiconductor fine particle composition according to any one of claims 1 to 3, having a structure. The semiconductor fine particle composition according to any one of claims 1 to 4, wherein the coating material has a heteroaromatic ring structure represented by any of the following formulas (3) to (6).
Equation (3)
Equation (4)
Equation (5)
[In the formula (5), Z represents O, S or NH. ]

Equation (6)
  The semiconductor fine particle composition according to any one of claims 1 to 5, wherein the semiconductor fine particles are quantum dots.   The semiconductor fine particle composition according to any one of claims 1 to 6, further comprising a solvent.   The semiconductor fine particle composition according to any one of claims 1 to 7, further comprising a resin.   A coating liquid comprising the semiconductor fine particle composition according to claim 1.   A coated article obtained by using the coating liquid according to claim 9.   An ink composition comprising the semiconductor fine particle composition according to claim 1.   An inkjet ink comprising the ink composition according to claim 11.   A printed matter using the ink composition according to claim 11.   A wavelength conversion film formed on a substrate using the coating liquid according to claim 9 or the ink composition according to claim 11.   A color filter formed on a substrate using the coating liquid according to claim 9 or the ink composition according to claim 11.   A light-emitting element in which a light-emitting layer is formed on a substrate using the coating liquid according to claim 9 or the ink composition according to claim 11.