Quantum dot composition, cured film and display device

Abstract

Provided are a quantum dot composition, a cured film and a display device, the quantum dot composition comprising: quantum dots having two different ligands; a photocurable monomer having an unsaturated double bond; a thermosetting monomer; and an initiator, wherein the thermosetting monomer includes an oxetane-based monomer, and the thermosetting monomer is included in an amount of 1-10 wt% in the composition.

Description

Quantum dot composition, cured film and display device

[0001] The present invention relates to a quantum dot composition, a cured film, and a display device.

[0002]

[0003] Quantum dot compositions containing quantum dots (QDs) are required to exhibit good patternability, prevent degradation of quantum dot light efficiency during thermal processing, exposure, development, washing, deposition, and additional thermal processes, and increase productivity. Cured films formed from the compositions may experience a decrease in the external quantum efficiency and light conversion retention of the quantum dots during subsequent thermal processes.

[0004] A cured film that can maintain external quantum efficiency and photoconversion retention rate even after undergoing thermal curing and subsequent thermal processes after photocuring is desirable.

[0005]

[0006] The present invention provides a quantum dot composition that minimizes the decrease in quantum efficiency of quantum dots even after undergoing a subsequent process after photocuring, thereby increasing the external quantum efficiency (EQE) and the maintenance rate of external quantum efficiency of quantum dots, and includes a thermosetting monomer without increasing viscosity.

[0007]

[0008] According to one embodiment, a quantum dot composition is provided.

[0009] The quantum dot composition comprises: quantum dots having two or more different ligands; a photocurable monomer having an unsaturated bond; a thermosetting monomer; and a photopolymerization initiator, wherein the thermosetting monomer comprises an oxetane-based monomer, and the thermosetting monomer is included in the composition in an amount of 1 to 10 wt%.

[0010] According to another embodiment, a cured film is provided.

[0011] The above cured film includes a cured product of the quantum dot composition.

[0012] In another embodiment, a display device is provided.

[0013] The above display device includes the above cured film.

[0014]

[0015] Even if the quantum efficiency of the quantum dot is reduced after a subsequent process after photocuring, the external quantum efficiency and the maintenance rate of the external quantum efficiency of the quantum dot are high, thereby increasing the reliability of the display device. In addition, even if a thermosetting monomer is included, the viscosity does not increase excessively, enabling inkjet jetting (printing), thereby providing a quantum dot composition with improved processability.

[0016]

[0017] Figure 1 is a conceptual diagram of a display device according to an embodiment.

[0018]

[0019] Hereinafter, embodiments of the present application will be described in more detail with reference to the attached drawings. However, the technology disclosed in the present application is not limited to the embodiments described herein and may be embodied in other forms. However, the embodiments introduced herein are provided so that the disclosed content can be thorough and complete and so that the spirit of the present application can be sufficiently conveyed to those skilled in the art. In order to clearly express the components of each device in the drawings, the sizes of the components, such as width and thickness, are somewhat enlarged. However, the sizes of the components, such as width and thickness, in the present invention do not limit the scope of the present invention. The same reference numerals in multiple drawings indicate substantially the same components.

[0020] The terminology used herein is for the purpose of describing exemplary embodiments only and is not intended to limit the present invention. Singular expressions include plural expressions unless the context clearly dictates otherwise.

[0021] In this specification, "upper" and "lower" are defined based on the drawing, and depending on the perspective, "upper" may be changed to "lower" and "lower" may be changed to "upper", and reference to "on" or "on" may include not only directly on but also cases where another structure is interposed in between. On the other hand, reference to "directly on" or "directly above" or "directly formed" indicates cases where there is no intervening other structure such as an intermediate body.

[0022] Unless otherwise specified herein, "alkyl group" means a C1 to C20 alkyl group, "alkenyl group" means a C2 to C20 alkenyl group, "cycloalkenyl group" means a C3 to C20 cycloalkenyl group, "heterocycloalkenyl group" means a C3 to C20 heterocycloalkenyl group, "aryl group" means a C6 to C20 aryl group, "arylalkyl group" means a C6 to C20 arylalkyl group, "alkylene group" means a C1 to C20 alkylene group, "arylene group" means a C6 to C20 arylene group, "alkylarylene group" means a C6 to C20 alkylarylene group, "heteroarylene group" means a C3 to C20 heteroarylene group, and "alkoxylene group" means a C1 to C20 It refers to an alkoxylene group.

[0023] Unless otherwise specified herein, "substitution" means that at least one hydrogen atom is substituted with a halogen atom (F, Cl, Br, I), a hydroxy group, a C1 to C20 alkoxy group, a nitro group, a cyano group, an amine group, an imino group, an azido group, an amidino group, a hydrazino group, a hydrazono group, a carbonyl group, a carbamyl group, a thiol group, an ester group, an ether group, a carboxyl group or a salt thereof, a sulfonic acid group or a salt thereof, a phosphoric acid or a salt thereof, a C1 to C20 alkyl group, a C2 to C20 alkenyl group, a C2 to C20 alkynyl group, a C6 to C20 aryl group, a C7 to C20 arylalkyl group, a C3 to C20 cycloalkyl group, a C3 to C20 cycloalkenyl group, a C3 to C20 cycloalkynyl group, a C2 to C20 heterocycloalkyl group, a C2 to C20 It means substituted with a heterocycloalkenyl group, a C2 to C20 heterocycloalkynyl group, a C3 to C20 heteroaryl group, or a combination thereof.

[0024] Additionally, unless otherwise specified herein, “hetero” means that the chemical formula contains at least one heteroatom of at least one of N, O, S, and P.

[0025] Additionally, unless otherwise specified herein, “(meth)acrylate” means both “acrylate” and “methacrylate”, and “(meth)acrylic acid” means both “acrylic acid” and “methacrylic acid”.

[0026] Unless otherwise specified herein, “combination” means mixing or copolymerization.

[0027] Unless otherwise defined in the chemical formulas herein, if a chemical bond is not drawn at a position where a chemical bond should be drawn, it means that a hydrogen atom is bonded at that position.

[0028] When describing a numerical range in this specification, “X to Y” means X or more and Y or less (X≤ and ≤Y).

[0029] A quantum dot composition including quantum dots should not only have an appropriate viscosity and excellent inkjet jetting properties, but also preferably have a high external quantum efficiency of the quantum dots and be maintained without decreasing when subjected to a subsequent process after photocuring by exposure.

[0030] Here, 'photocuring by exposure' means light irradiation at a wavelength of 190 nm to 450 nm, for example 200 nm to 500 nm.

[0031] Here, the 'subsequent process' may include a heat treatment at a temperature of 180°C or higher, for example, 180 to 200°C, for 1 to 60 minutes in a nitrogen atmosphere or air. In the above-described subsequent process, the heat treatment may be performed one or more times, for example, two or more times.

[0032] According to one embodiment, the quantum dot composition may be capable of inkjet jetting without significantly increasing viscosity even if it includes a thermosetting monomer, thereby improving processability.

[0033] According to one embodiment, the quantum dot composition may preferably have a viscosity of 5 to 27 cps at 25°C. Within this range, the inkjet jetting properties are excellent, allowing a uniform cured film to be formed, and processability may be improved.

[0034] The external quantum efficiency of the quantum dot may gradually decrease as it goes through the subsequent process. Therefore, in order to prevent the decrease in the external quantum efficiency of the quantum dot, a thermosetting monomer is added to the composition to increase the crosslinking density of the cured film, thereby maintaining the external quantum efficiency of the quantum dot. However, in order to thermally cure the thermosetting monomer, an acid catalyst or an amine catalyst must be additionally included in the composition. The amine catalyst can increase the viscosity of the composition and cause the decomposition of the thermosetting monomer and / or the decomposition of the quantum dot in the liquid state. The acid catalyst can also decompose the quantum dot.

[0035] The quantum dot composition according to one embodiment does not include the above-described acid catalyst, amine catalyst, and thermal polymerization initiator, and by thermally curing the thermosetting monomer during the subsequent process, the degree of decrease in the external quantum efficiency of the quantum dot is low even after the subsequent process after photocuring, so that the photoconversion rate and photoconversion maintenance rate are high, thereby increasing the reliability of the display device.

[0036] In this regard, a specimen manufactured with the quantum dot composition may have an external quantum efficiency of 29.9% or more, for example, 29.9 to 35%, after being cured (POB) in a nitrogen atmosphere at 180°C for 30 minutes.

[0037] In this regard, a specimen manufactured with the quantum dot composition may be cured (POB) in a nitrogen atmosphere at 180°C for 30 minutes and cured (CVD) in air at 200°C for 5 minutes, and then have an external quantum efficiency of 29.5% or more, for example, 29.5 to 35%.

[0038] The specimen manufactured with the above quantum dot composition was coated with the above quantum dot composition to a thickness of 15 μm and exposed to 5000 mJ / cm at a wavelength of 395 nm under a nitrogen atmosphere. 2 It can be manufactured by exposure to light.

[0039] The quantum dot composition comprises quantum dots having two different ligands; a photocurable monomer having an unsaturated bond; a thermosetting monomer; and a photopolymerization initiator, wherein the thermosetting monomer comprises an oxetane-based monomer, and the thermosetting monomer is included in the composition in an amount of 1 to 10 wt%.

[0040] The content range of the thermosetting monomer in the above composition was set in consideration of the ratio of the curable ligand having a carboxylic acid group among the total ligands possessed by the quantum dot and the subsequent process. The curable ligand having a carboxylic acid group has a carboxylic acid group partially desorbed from the quantum dot during the subsequent process, and the exposed carboxylic acid group can catalyze the thermal curing of the thermosetting monomer.

[0041] When the thermosetting monomer is included in the composition in an amount of 1 wt% or more, thermal curing occurs during the subsequent process, thereby preventing a decrease in the external quantum efficiency of the quantum dot due to the addition of the thermosetting monomer. When the thermosetting monomer is included in the composition in an amount of 10 wt% or less, thermal curing of the thermosetting monomer by the ligand is sufficiently performed, thereby obtaining excellent reliability. In addition, the decrease in the light transmittance of the cured film due to unreaction can be prevented, thereby preventing a decrease in the optical properties of the quantum dot. In addition, the increase in viscosity of the composition can be prevented, thereby ensuring inkjet jetting properties.

[0042] According to one embodiment, the quantum dot composition may be solvent-free. Although the composition is solvent-free, it may have excellent inkjet jetting properties.

[0043] Hereinafter, each component of the quantum dot composition will be described in detail.

[0044] Quantum dots with two different ligands

[0045] The above quantum dot has two different ligands. For convenience, the ligands are referred to as the first ligand and the second ligand.

[0046] The first ligand may be a ligand derived from a first modified material that is a curable material and has a carboxylic acid group. For example, the first modified material may be a photocurable material or a thermocurable material and have one or more carboxylic acid groups.

[0047] The second ligand may be a ligand derived from a second modifying material having one or more thiol groups. For example, the second modifying material may have one thiol group. The second modifying material may not only improve the heat resistance of the quantum dot, but also catalyze the thermal curing of the thermosetting monomer by allowing the modifying material having the carboxylic acid group to be easily separated in the subsequent process.

[0048] According to one embodiment, the quantum dot is modified with a mixture of the first modifying material and the second modifying material, and the first modifying material and the second modifying material in the mixture may be included in a weight ratio of 80:20 to 20:80 based on a total of 100 parts by weight. Within this range, the effect of improving the heat resistance of the thermosetting catalyst and the quantum dot of the thermosetting monomer can be obtained.

[0049] For example, the first modifying material in the mixture: the second modifying material may be included in a weight ratio of 50:50 to 70:30 based on 100 parts by weight of the total. In the above range, the quantum dot composition may have an appropriate viscosity, which is very advantageous for inkjet jetting properties, and the photoconversion retention rate considering the EQE (external quantum efficiency) after photocuring by exposure of the quantum dot composition and the EQE after a subsequent process may be remarkably high. Here, the 'photoconversion retention rate' is described in more detail in the following experimental method, and reference is made thereto. For example, the weight ratio may be 50:50, 55:45, 60:40, 65:35, or 70:30.

[0050] In one specific example, the quantum dot may be modified with a mixture comprising the first modifying material and the second modifying material. In this case, the sum of the first modifying material and the second modifying material may be comprised in an amount of 95 wt% or more, for example, 99 to 100 wt%, or 100 wt%, of the mixture.

[0051] In one specific example, the first modified material may include one or more of the compounds represented by the following chemical formula 1:

[0052] [Chemical Formula 1]

[0053]

[0054] (In the above chemical formula 1,

[0055] R 1 is a substituted or unsubstituted C1 to C10 alkyl group or a substituted or unsubstituted C6 to C20 aryl group,

[0056] L 11 Inland L 13 are each independently a substituted or unsubstituted C1 to C10 alkylene group, ester group or ether group,

[0057] n is an integer from 1 to 20, except that L 12 It is an ester group and at the same time L 13 When this is an unsubstituted C1 to C10 alkylene group, n is an integer from 4 to 20.

[0058] For example, in the chemical formula 1 above, L 11 and L 13 are each independently a substituted or unsubstituted C1 to C10 alkylene group, and L 12 It can be an ester group (*-C(=O)O-* or *-O(C=O)-*) or an ether group (*-O-*).

[0059] The compound represented by the above chemical formula 1 may include at least one selected from the group consisting of the following chemical formulas 1-1 to 1-10, but is not necessarily limited thereto.

[0060] [Chemical Formula 1-1]

[0061]

[0062] [Chemical Formula 1-2]

[0063]

[0064] [Chemical Formula 1-3]

[0065]

[0066] [Chemical Formula 1-4]

[0067]

[0068] [Chemical Formula 1-5]

[0069]

[0070] [Chemical Formula 1-6]

[0071]

[0072] [Chemical Formula 1-7]

[0073]

[0074] [Chemical Formula 1-8]

[0075]

[0076] [Chemical Formula 1-9]

[0077]

[0078] [Chemical Formula 1-10]

[0079]

[0080] Preferably, the first modifying material may be a compound of the following chemical formula 1-11:

[0081] [Chemical Formula 1-11]

[0082]

[0083] (n is an integer from 1 to 10)

[0084] The second modified material may include at least one compound represented by the following chemical formula 2:

[0085] [Chemical Formula 2]

[0086]

[0087] (In the above chemical formula 2,

[0088] R 2 is a substituted or unsubstituted C2 to C10 alkenyl group,

[0089] L 21 Inland L 23 are each independently a single bond, a substituted or unsubstituted C1 to C10 alkylene group, an ester group or an ether group,

[0090] m is an integer from 1 to 10)

[0091] Preferably, the second modifying material may be a compound of the following chemical formula 2-1:

[0092] [Chemical Formula 2-1]

[0093]

[0094] (m is an integer from 1 to 10)

[0095] The above quantum dots may have a maximum fluorescence emission wavelength of 500 nm to 680 nm.

[0096] Surface modification of the quantum dot by the first modifying material and the second modifying material can be performed by referring to a method known to those skilled in the art.

[0097] When the quantum dot composition according to one embodiment is a solvent-free quantum dot composition, the quantum dots may be included in an amount of 5 to 60 wt%, for example, 10 to 60 wt%, for example, 20 to 60 wt%, for example, 30 to 50 wt%. When the quantum dots are included within the above range, high light retention and light efficiency can be achieved even after curing.

[0098] When the quantum dot composition according to one embodiment is a quantum dot composition including a solvent, the quantum dots may be included in an amount of 1 to 40 wt%, for example, 3 to 30 wt%, based on the total amount of the quantum dot composition. When the quantum dots are included within the above range, the photoconversion rate is excellent and the pattern characteristics and development characteristics are not impaired, thereby enabling excellent processability.

[0099] The quantum dot can absorb light in a wavelength range of 360 nm to 780 nm, for example, a wavelength range of 400 nm to 780 nm, and emit fluorescence in a wavelength range of 500 nm to 700 nm, for example, 500 nm to 580 nm, or emit fluorescence in a wavelength range of 600 nm to 680 nm. That is, the quantum dot can have a maximum fluorescence emission wavelength (fluorescence λ) in a wavelength range of 500 nm to 680 nm. em ) can have.

[0100] The above quantum dots may each independently have a full width at half maximum (FWHM) of 20 nm to 100 nm, for example, 20 nm to 50 nm. When the quantum dots have a full width at half maximum (FWHM) within the above range, the color purity is high, thereby increasing the color reproducibility when used as a color material in a color filter.

[0101] The above quantum dots may each independently be organic, inorganic, or a hybrid (hybrid) of organic and inorganic materials.

[0102] The above quantum dots can each independently be composed of a core and a shell surrounding the core, and the core and shell can each independently have a structure such as a core, core / shell, core / first shell / second shell, alloy, alloy / shell, etc., made of group II-IV, group III-V, etc., but are not limited thereto.

[0103] For example, the core may include at least one material selected from the group consisting of CdS, CdSe, CdTe, ZnS, ZnSe, ZnTe, HgS, HgSe, HgTe, GaN, GaP, GaAs, InP, InAs, and alloys thereof, but is not necessarily limited thereto. The shell surrounding the core may include at least one material selected from the group consisting of CdSe, ZnSe, ZnS, ZnTe, CdTe, PbS, TiO, SrSe, HgSe, and alloys thereof, but is not necessarily limited thereto.

[0104] In one implementation example, since environmental concerns have been increasing significantly worldwide and regulations on toxic substances have been strengthened, environmentally friendly non-cadmium-based luminescent materials (such as InP / ZnS, InP / ZeSe / ZnS) with somewhat lower quantum yields were used instead of luminescent materials having cadmium-based cores, but the present invention is not limited thereto.

[0105] In the case of the quantum dot of the above core / shell structure, the size (average particle diameter) of each quantum dot including the shell may be 1 nm to 15 nm, for example, 5 nm to 15 nm.

[0106] For example, the quantum dots may each independently include red quantum dots, green quantum dots, or a combination thereof. The red quantum dots may each independently have an average particle diameter of 10 nm to 15 nm. The green quantum dots may each independently have an average particle diameter of 5 nm to 8 nm.

[0107] Meanwhile, in order to ensure dispersion stability of the quantum dots, the quantum dot composition according to one embodiment may further include a dispersant. The dispersant helps to uniformly disperse the photoconversion material, such as quantum dots, within the quantum dot composition, and any nonionic, anionic, or cationic dispersant may be used. Specifically, polyalkylene glycol or its esters, polyoxyalkylene, polyhydric alcohol ester alkylene oxide adducts, alcohol alkylene oxide adducts, sulfonic acid esters, sulfonic acid salts, carboxylic acid esters, carboxylic acid salts, alkyl amide alkylene oxide adducts, alkyl amines, and the like may be used alone or in combination of two or more. The dispersant may be used in an amount of 0.1 wt% to 100 wt%, for example, 10 wt% to 20 wt%, relative to the solid content of the photoconversion material, such as quantum dots.

[0108] Photocurable monomer with unsaturated bonds

[0109] The quantum dot composition comprises a photocurable monomer containing an unsaturated bond. For example, the photocurable monomer may be a photocurable monomer having a carbon-carbon double bond at the terminal.

[0110] The photocurable monomer may be included in an amount of 30 to 70 wt%, for example, 40 to 70 wt%, for example, 45 to 65 wt%, for example, 45 to 60 wt%, based on the total amount of the quantum dot composition (e.g., based on solid content). Within this range, a composition having a viscosity that enables inkjet jetting of the composition, particularly a solvent-free quantum dot composition, can be produced, and furthermore, the quantum dots in the produced composition, particularly the solvent-free quantum dot composition, can have excellent dispersibility, so that the optical properties can also be improved.

[0111] The photocurable monomer may have a molecular weight of 150 g / mol to 1,000 g / mol. Within this range, the composition may be advantageous for ink-jetting because the viscosity of the composition may not be increased without impairing the optical properties of the quantum dots.

[0112] The above photocurable monomer may be represented by the following chemical formula 3, but is not necessarily limited thereto:

[0113] [Chemical Formula 3]

[0114]

[0115] (In the above chemical formula 3,

[0116] R 3 and R 4 are each independently a hydrogen atom or a substituted or unsubstituted C1 to C10 alkyl group,

[0117] L 31 and L 33 are each independently a substituted or unsubstituted C1 to C10 alkylene group,

[0118] L 32 is a substituted or unsubstituted C1 to C10 alkylene group or ether group (*-O-*).

[0119] For example, the photocurable monomer may include at least one of the following chemical formulas 3-1 and 3-2, but is not necessarily limited thereto.

[0120] [Chemical Formula 3-1]

[0121]

[0122] [Chemical Formula 3-2]

[0123]

[0124] For example, the photocurable monomer, in addition to the compounds represented by the chemical formulas 3-1 and 3-2, may be selected from the group consisting of ethylene glycol diacrylate, triethylene glycol diacrylate, 1,4-butanediol diacrylate, 1,6-hexanediol diacrylate, neopentyl glycol diacrylate, pentaerythritol diacrylate, pentaerythritol triacrylate, dipentaerythritol diacrylate, dipentaerythritol triacrylate, dipentaerythritol pentaacrylate, pentaerythritol hexaacrylate, bisphenol A diacrylate, trimethylolpropane triacrylate, novolac epoxy acrylate, ethylene glycol dimethacrylate, triethylene glycol dimethacrylate, propylene glycol dimethacrylate, 1,4-butanediol dimethacrylate, 1,6-hexanedioldimethacrylate or a combination thereof may be further included.

[0125] thermosetting monomer

[0126] The above thermosetting monomer can further increase the crosslinking density of the cured film by being thermosetted in a subsequent process of the quantum dot composition, thereby reducing the degree of quantum efficiency degradation of the quantum dot and improving the reliability of the display device.

[0127] The above thermosetting monomer includes an oxetane monomer. The oxetane monomer has lower molecular stress within the ring than the epoxy monomer, and thus may have higher stability in subsequent processes.

[0128] According to one embodiment, the oxetane monomer may be included in an amount of 95 wt% or more, for example, 99 to 100 wt%, or 100 wt%, of the thermosetting monomer. Within this range, the viscosity of the composition does not increase, and the effect of thermosetting can be obtained.

[0129] The above oxetane monomer may have 1 to 5 oxetane groups, for example, 1, 2, 3, 4 or 5 oxetane groups.

[0130] The above oxetane monomer may have a ring structure and / or a straight-chain or branched-chain structure within its molecular structure. For example, the oxetane monomer may have a straight-chain, branched-chain or cyclic C1 to C10 alkane group, a straight-chain, branched-chain or cyclic C1 to C10 alkene group, or a C6 to C20 arylene group. The oxetane monomer may also have an ether group or an ester group.

[0131] In one specific example, the oxetane monomer may include at least one of the following chemical formulas 4-1 and 4-2:

[0132] [Chemical Formula 4-1]

[0133]

[0134] [Chemical Formula 4-2]

[0135]

[0136] (In the above chemical formulas 4-1 and 4-2,

[0137] L 42 is straight chain or branched chain C1-C 20 Alkane group, or straight chain, or branched chain C1-C 20 It is an alkene group,

[0138] L 43 Silver ring C1-C 20 Alkane or cyclic C1-C 20 It is an alkene group,

[0139] L 41 is *-O-*', or And,

[0140] a is 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10,

[0141] R 41 Inland R 45 are independently hydrogen, deuterium, halogen elements, or straight, branched or cyclic C1-C 20 It is an alkyl group;

[0142] b is an integer from 1 to 12,

[0143] p is 1, 2, 3, 4, or 5,

[0144] * and *' are bonding sites with neighboring atoms, respectively.

[0145] In one specific example, the oxetane monomer includes, but is not limited to, 1,4-bis[(3-ethyl-3-oxetanyl methoxy)methyl]benzene, 1,4-bis[(3-methyl-3-oxetanyl methoxy)methyl]benzene, 3-methyl-3-glycidyl oxetane, 3-ethyl-3-glycidyl oxetane, bis[1-ethyl(3-oxetanyl)]methyl ether, 3-ethyl-3-hydroxymethyl oxetane, 3-ethyl-3-[(3-ethoxyoxetan-3-yl)methoxy] oxetane, 3-ethyl-3-phenoxymethyl oxetane, 3-ethyl-3-[(2-ethylhexyloxy)methyl] oxetane, oxetanyl-silicate, phenol novolak oxetane, and the like.

[0146] The thermosetting monomer is included in an amount of 1 to 10 wt% based on the total amount of the quantum dot composition (e.g., based on solid content). This has been described above and is therefore omitted. For example, the thermosetting monomer may be included in an amount of 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10 wt%, for example, 3 to 7 wt%.

[0147] Initiator

[0148] The curable composition according to one embodiment may further comprise an initiator, for example, a photopolymerization initiator, a thermal polymerization initiator, or a combination thereof.

[0149] The above photopolymerization initiator is an initiator capable of initiating a polymerization reaction by light, and examples thereof include, but are not limited to, acetophenone-based compounds, benzophenone-based compounds, thioxanthone-based compounds, benzoin-based compounds, triazine-based compounds, oxime-based compounds, and aminoketone-based compounds.

[0150] Examples of the above acetophenone compounds include 2,2'-diethoxy acetophenone, 2,2'-dibutoxy acetophenone, 2-hydroxy-2-methylpropiophenone, pt-butyltrichloro acetophenone, pt-butyldichloro acetophenone, 4-chloro acetophenone, 2,2'-dichloro-4-phenoxy acetophenone, 2-methyl-1-(4-(methylthio)phenyl)-2-morpholinopropan-1-one, 2-benzyl-2-dimethylamino-1-(4-morpholinophenyl)-butan-1-one, etc.

[0151] Examples of the above benzophenone compounds include benzophenone, benzoyl benzoate, methyl benzoyl benzoate, 4-phenyl benzophenone, hydroxybenzophenone, acrylated benzophenone, 4,4'-bis(dimethylamino)benzophenone, 4,4'-bis(diethylamino)benzophenone, 4,4'-dimethylaminobenzophenone, 4,4'-dichlorobenzophenone, 3,3'-dimethyl-2-methoxybenzophenone, etc.

[0152] Examples of the above thioxanthone compounds include thioxanthone, 2-methylthioxanthone, isopropyl thioxanthone, 2,4-diethyl thioxanthone, 2,4-diisopropyl thioxanthone, 2-chlorothioxanthone, etc.

[0153] Examples of the above benzoin compounds include benzoin, benzoin methyl ether, benzoin ethyl ether, benzoin isopropyl ether, benzoin isobutyl ether, benzyldimethyl ketal, etc.

[0154] Examples of the above triazine compounds include 2,4,6-trichloro-s-triazine, 2-phenyl-4,6-bis(trichloromethyl)-s-triazine, 2-(3',4'-dimethoxystyryl)-4,6-bis(trichloromethyl)-s-triazine, 2-(4'-methoxynaphthyl)-4,6-bis(trichloromethyl)-s-triazine, 2-(p-methoxyphenyl)-4,6-bis(trichloromethyl)-s-triazine, 2-(p-tolyl)-4,6-bis(trichloromethyl)-s-triazine, 2-biphenyl-4,6-bis(trichloromethyl)-s-triazine, bis(trichloromethyl)-6-styryl-s-triazine, Examples thereof include 2-(naphtho-1-yl)-4,6-bis(trichloromethyl)-s-triazine, 2-(4-methoxynaphtho-1-yl)-4,6-bis(trichloromethyl)-s-triazine, 2-4-bis(trichloromethyl)-6-piperonyl-s-triazine, and 2-4-bis(trichloromethyl)-6-(4-methoxystyryl)-s-triazine.

[0155] Examples of the above oxime compounds include O-acyloxime compounds, 2-(O-benzoyloxime)-1-[4-(phenylthio)phenyl]-1,2-octanedione, 1-(O-acetyloxime)-1-[9-ethyl-6-(2-methylbenzoyl)-9H-carbazol-3-yl]ethanone, O-ethoxycarbonyl-α-oxyamino-1-phenylpropan-1-one, etc. Specific examples of the O-acyl oxime compounds include 1,2-octanedione, 2-dimethylamino-2-(4-methylbenzyl)-1-(4-morpholin-4-yl-phenyl)-butan-1-one, 1-(4-phenylsulfanylphenyl)-butane-1,2-dione-2-oxime-O-benzoate, 1-(4-phenylsulfanylphenyl)-octane-1,2-dione-2-oxime-O-benzoate, 1-(4-phenylsulfanylphenyl)-octane-1-oneoxime-O-acetate, and 1-(4-phenylsulfanylphenyl)-butan-1-oneoxime-O-acetate.

[0156] Examples of the above aminoketone compounds include 2-Benzyl-2-dimethylamino-1-(4-morpholinophenyl)-butanone-1.

[0157] In addition to the above compound, the photopolymerization initiator may also include a carbazole compound, a diketone compound, a sulfonium borate compound, a diazo compound, an imidazole compound, a biimidazole compound, etc.

[0158] The above photopolymerization initiator may also be used together with a photosensitizer that causes a chemical reaction by absorbing light, becoming excited, and then transferring the energy.

[0159] Examples of the above photosensitizer include tetraethylene glycol bis-3-mercapto propionate, pentaerythritol tetrakis-3-mercapto propionate, dipentaerythritol tetrakis-3-mercapto propionate, and the like.

[0160] Examples of the above thermal polymerization initiator include peroxides, specifically benzoyl peroxide, dibenzoyl peroxide, lauryl peroxide, dilauryl peroxide, di-tert-butyl peroxide, cyclohexane peroxide, methyl ethyl ketone peroxide, hydroperoxides (e.g., tert-butyl hydroperoxide, cumene hydroperoxide), dicyclohexyl peroxydicarbonate, 2,2-azo-bis(isobutyronitrile), t-butyl perbenzoate, etc., and 2,2'-azobis-2-methylpropionitrile, etc., but are not necessarily limited thereto, and any one widely known in the art can be used.

[0161] The photopolymerization initiator may be included in an amount of 0.1 to 5 wt%, for example, 1 to 4 wt%, based on the total amount of the quantum dot composition (e.g., based on solid content). When included within the above range, sufficient curing occurs upon exposure to light or thermal curing, thereby achieving excellent reliability, and preventing a decrease in transmittance due to unreacted initiator, thereby preventing a decrease in the optical properties of the quantum dot.

[0162] light scattering agent

[0163] A quantum dot composition according to one embodiment may further include a light scattering agent.

[0164] The above light scattering agent may include barium sulfate (BaSO4), calcium carbonate (CaCO3), titanium dioxide (TiO2), zirconia (ZrO2), or a combination thereof.

[0165] The light-scattering agent reflects light not absorbed by the aforementioned quantum dots and allows the reflected light to be reabsorbed by the quantum dots. In other words, the light-scattering agent can increase the amount of light absorbed by the quantum dots, thereby increasing the photoconversion efficiency of the quantum dot composition.

[0166] The above light scattering agent has an average particle diameter (D 50 ) may be 150 nm to 250 nm, and specifically, 180 nm to 230 nm. When the average particle diameter of the light diffusing agent is within the above range, it may have a better light diffusing effect and increase the light conversion efficiency.

[0167] The light-scattering agent may be included in an amount of 1 to 20 wt%, for example 2 to 15 wt%, for example 3 to 10 wt%, based on the total amount of the quantum dot composition (e.g., based on solid content). Within this range, an effect of improving the light conversion efficiency due to the use of the light-scattering agent can be expected, and quantum dot sedimentation problems may not occur.

[0168] additives

[0169] In order to improve the stability and dispersibility of the above quantum dots, the solvent-free quantum dot composition according to one embodiment may further include a polymerization inhibitor.

[0170] The polymerization inhibitor may include, but is not necessarily limited to, a hydroquinone-based compound, a catechol-based compound, or a combination thereof. According to one embodiment, since the solvent-free quantum dot composition further includes the hydroquinone-based compound, the catechol-based compound, or a combination thereof, crosslinking at room temperature can be prevented during exposure after printing (coating) the solvent-free quantum dot composition.

[0171] For example, the hydroquinone-based compound, catechol-based compound, or combinations thereof may include, but are not necessarily limited to, hydroquinone, methyl hydroquinone, methoxyhydroquinone, t-butyl hydroquinone, 2,5-di-t-butyl hydroquinone, 2,5-bis(1,1-dimethylbutyl) hydroquinone, 2,5-bis(1,1,3,3-tetramethylbutyl) hydroquinone, catechol, t-butyl catechol, 4-methoxyphenol, pyrogallol, 2,6-di-t-butyl-4-methylphenol, 2-naphthol, tris(N-hydroxy-N-nitrosophenylaminato-O,O')aluminium, or combinations thereof.

[0172] The above hydroquinone-based compound, catechol-based compound, or a combination thereof may be used in the form of a dispersion, and the polymerization inhibitor in the form of the dispersion may be included in an amount of 0.001 wt% to 3 wt%, for example, 0.1 wt% to 2 wt%, based on the total amount of the solvent-free quantum dot composition. When the polymerization inhibitor is included within the above range, the problem of aging at room temperature can be solved, while at the same time preventing a decrease in sensitivity and surface peeling.

[0173] The solvent in the above composition may be included in an amount of 2 parts by weight or less, for example, 0 to 2 parts by weight, per 100 parts by weight of the solid content of the above composition.

[0174] In addition, the quantum dot composition according to one embodiment may further include malonic acid; 3-amino-1,2-propanediol; a silane coupling agent; a leveling agent; a fluorinated surfactant; or a combination thereof to improve heat resistance and reliability.

[0175] For example, the quantum dot composition according to one embodiment may further include a silane coupling agent having a reactive substituent such as a vinyl group, a carboxyl group, a methacryloxy group, an isocyanate group, or an epoxy group to improve adhesion to a substrate, etc.

[0176] Examples of the above silane coupling agent include trimethoxysilyl benzoic acid, γ-methacryloxypropyl trimethoxysilane, vinyl triacetoxysilane, vinyl trimethoxysilane, γ-isocyanate propyl triethoxysilane, γ-glycidoxy propyl trimethoxysilane, β-epoxycyclohexyl)ethyl trimethoxysilane, etc., and these may be used alone or in combination of two or more.

[0177] The above silane coupling agent may be included in an amount of 0.01 to 10 parts by weight based on 100 parts by weight of the quantum dot composition. When the silane coupling agent is included within the above range, adhesion, storability, etc. are excellent.

[0178] In addition, the solvent-free quantum dot composition may further include a surfactant, such as a fluorinated surfactant, if necessary, to improve coating properties and prevent defect formation, i.e., to improve leveling performance. The fluorinated surfactant may have a low weight average molecular weight of 4,000 g / mol to 10,000 g / mol, specifically, a weight average molecular weight of 6,000 g / mol to 10,000 g / mol. In addition, the fluorinated surfactant may have a surface tension of 18 mN / m to 23 mN / m (measured in a 0.1% propylene glycol monomethyl ether acetate (PGMEA) solution). When the weight average molecular weight and surface tension of the above fluorinated surfactant are within the above range, the leveling performance can be further improved, the occurrence of stains can be prevented during high-speed coating, and since the occurrence of bubbles is small and the film defects are small, it provides excellent characteristics to slit coating, which is a high-speed coating method.

[0179] Additionally, the quantum dot composition according to one embodiment may use a silicone-based surfactant together with the aforementioned fluorine-based surfactant. Specific examples of the silicone-based surfactant include, but are not limited to, TSF400, TSF401, TSF410, and TSF4440 from Toshiba Silicone Co., Ltd.

[0180] The surfactant, including the fluorinated surfactant, may be included in an amount of 0.01 to 5 parts by weight, for example, 0.1 to 2 parts by weight, based on 100 parts by weight of the solvent-free quantum dot composition. When the surfactant is included within the above range, the phenomenon of foreign substances occurring in the sprayed composition is reduced.

[0181] In addition, the quantum dot composition according to one embodiment may further include a certain amount of other additives, such as antioxidants, within a range that does not impair physical properties.

[0182] Another aspect provides a cured film manufactured using the quantum dot composition and a display device including the cured film.

[0183] According to one embodiment, the cured film comprises a cured product of the quantum dot composition.

[0184] One of the methods for manufacturing the above-mentioned cured film includes a step (S1) of forming a pattern by applying the above-mentioned quantum dot composition onto a substrate using an inkjet jetting method; and a step (S2) of curing the pattern.

[0185] (S1) Pattern forming step

[0186] The above quantum dot composition is preferably applied to a substrate at a thickness of 0.5 to 20 μm using an inkjet jetting method. The inkjet jetting method can form a pattern by repeatedly spraying only a single color from each nozzle according to the required number of colors. To reduce the process, the pattern can also be formed by simultaneously spraying the required number of colors through each inkjet nozzle.

[0187] The above inkjet jetting method can use an inkjet printer having an inkjet head equipped with a piezo-type nozzle that applies pressure according to voltage.

[0188] More specifically, the quantum dot composition is ejected from a nozzle of an inkjet head onto a substrate. At this time, the ejection amount of the composition may be 1 to 80 pL / time, for example, 1 to 30 pL / time, or as another example, 1 to 20 pL / time.

[0189] The aperture of the inkjet head may be, but is not limited to, 5 to 100 μm, for example, 10 to 80 μm, to minimize clogging of the nozzle and improve ejection precision.

[0190] The ejection pressure of the inkjet head is 1000 to 100000s based on the shear speed. -1It may be, but is not limited to,

[0191] The temperature at the time of discharge is not particularly limited, but may be 10 to 120°C, for example, 15 to 60°C, as another example, 15 to 40°C, or as another example, 20 to 35°C, from the viewpoint of suppressing crystallization of materials included in the ink composition.

[0192] (S2) Hardening stage

[0193] The pattern obtained above can be cured to obtain pixels. At this time, a photocuring process can be applied as a curing method. The photocuring process irradiates active rays such as UV rays having a wavelength of 190 nm to 450 nm, for example, 200 nm to 500 nm. Light sources used for irradiation include low-pressure mercury lamps, high-pressure mercury lamps, ultra-high-pressure mercury lamps, metal halide lamps, argon gas lasers, etc., and in some cases, X-rays, electron beams, etc. can also be used.

[0194] Another method of manufacturing the above-mentioned cured film is to manufacture the cured film using the above-mentioned quantum dot composition using a lithography method, and the manufacturing method is as follows.

[0195] (1) Application and film formation stage

[0196] The above-described quantum dot composition is applied to a substrate that has undergone a predetermined pretreatment using a spin or slit coating method, a roll coating method, a screen printing method, an applicator method, or the like to a desired thickness, for example, 2 μm to 10 μm, and then heated at a temperature of 70°C to 90°C for 1 to 10 minutes to remove the solvent, thereby forming a film.

[0197] (2) Exposure stage

[0198] In order to form a necessary pattern on the obtained film, a mask of a predetermined shape is interposed, and then an active ray such as UV light of 190 nm to 450 nm, for example, 200 nm to 500 nm, is irradiated. Light sources used for irradiation include low-pressure mercury lamps, high-pressure mercury lamps, ultra-high-pressure mercury lamps, metal halide lamps, argon gas lasers, etc., and in some cases, X-rays, electron beams, etc. can also be used.

[0199] The exposure dose varies depending on the type, mixing amount, and dry film thickness of each component of the quantum dot composition, but for example, when using a high-pressure mercury lamp, it is 500 mJ / cm 2　 Below (based on 365 nm sensor).

[0200] (3) Phenomenon stage

[0201] Following the above exposure step, an alkaline aqueous solution is used as a developer to dissolve and remove unnecessary portions, thereby leaving only the exposed portions to form an image pattern. That is, when developing with an alkaline developer, the unexposed portions are dissolved, and an image color filter pattern is formed.

[0202] (4) Post-processing stage

[0203] The image pattern obtained by the above phenomenon can be cured by reheating or irradiating with active rays, etc., to obtain a pattern superior in terms of heat resistance, light resistance, adhesion, crack resistance, chemical resistance, high strength, storage stability, etc.

[0204] Another viewpoint is the display device, which includes the cured film.

[0205] According to one embodiment, the display device includes a color filter layer including the cured film. According to one embodiment, the display device may be a light-emitting element display device including an organic light-emitting display device.

[0206] Figure 1 is a cross-sectional view of a light-emitting display device according to an embodiment.

[0207] Referring to FIG. 1, a display device (11) according to one embodiment includes a first substrate (111), two or more first electrodes (112) formed on the first substrate (111), a pixel defining film (113) formed between adjacent first electrodes (112), and a light source (10) including an organic light-emitting layer (120) formed on each of the first electrodes (112) and emitting a first light, a second electrode layer (114) formed on the organic light-emitting layer (120), and a first planarization layer (115) formed on the second electrode layer (114), a sealing layer (119) formed on the first planarization layer (115), a second planarization layer (118) formed on the sealing layer (119), and a quantum dot (3, 3r, 3g) formed on the second planarization layer (118) and converting the first light into at least one of different second light and third light. It includes a color filter layer (130) and a second substrate (116) formed on the color filter layer (130).

[0208] In a display device (11) according to one embodiment, the organic light-emitting layer (120) can be defined as a first pixel area, a second pixel area, and a third pixel area, and each pixel area is spaced apart at a predetermined interval by a pixel definition film (113). In one embodiment, unit layers belonging to the first to third pixel areas of the organic light-emitting layer (120) are defined as first to third organic light-emitting layers (120a to 120c), respectively.

[0209] The color filter layer (130) is formed to cover the space between adjacent light-blocking members (117). The color filter layer (130) includes first to third color filters (130r, 130g, 130b) formed at positions that overlap the first to third pixel areas described above, respectively.

[0210] In one embodiment, the first color filter (130r) can emit a second light different from the first light, the second color filter (130g) can emit a third light different from the first light, and the third color filter (130b) can emit the first light. For example, the first light can be blue light, the second light can be red light, and the third light can be green light.

[0211] Although not shown in FIG. 1, the display device may further include a color conversion layer.

[0212]

[0213] Hereinafter, the structure and operation of the present invention will be described in more detail through preferred embodiments of the present invention. However, these are presented as preferred examples of the present invention and should not be construed as limiting the present invention in any way.

[0214]

[0215] Manufacturing Example 1

[0216] (Manufacture of surface-modified quantum dots)

[0217] A magnetic bar is placed in a three-necked round bottom flask, and a green quantum dot dispersion solution (InP / ZnSe / ZnS, Hansol Chemical; quantum dot solid content 23 wt%) is added.

[0218] Here, a compound represented by the following chemical formula 1-10 and a compound represented by the following chemical formula 2-1 are added in a weight ratio of 80:20, and stirred at 80°C in a nitrogen atmosphere. After the reaction is complete, cool to room temperature (23°C), and then add the quantum dot reaction solution to cyclohexane to precipitate. The precipitate and cyclohexane are separated by centrifugation, and the precipitate is sufficiently dried in a vacuum oven for one day to obtain green quantum dots surface-modified with the two compounds mentioned above.

[0219] [Chemical Formula 1-10]

[0220]

[0221] [Chemical Formula 2-1]

[0222]

[0223] Manufacturing Examples 2 to 9

[0224] Surface-modified green quantum dots are obtained in the same manner as in Manufacturing Example 1, except that the weight ratio of the compound represented by Chemical Formula 1-10 and the compound represented by Chemical Formula 2-1 is changed as shown in Table 1 below.

[0225] Manufacturing Example 123456789 Chemical Formula 1-10807060504030201000 Chemical Formula 2-1203040506070800100

[0226]

[0227] (Manufacturing of quantum dot composition)

[0228] (A) Quantum dots: Surface-modified quantum dots manufactured in Manufacturing Examples 1 to 9

[0229] (B) Photocurable monomer with unsaturated double bond; 1,6-hexanediol diacrylate (Miwon Specialty Chemical Co., Ltd.)

[0230] (C) Thermosetting monomer; Monomer of the chemical formula below (bis[1-ethyl(3-oxetanyl)]methyl ether (OXT-221)

[0231] [chemical formula]

[0232]

[0233] (D) Photopolymerization initiator: TPO-L (Polynetran)

[0234] (E) Light scattering agent: Titanium dioxide dispersion (rutile type TiO2; D50 (180 nm), solid content 50 wt%, Iridos Co., Ltd.)

[0235] (F) Polymerization inhibitor: Methylhydroquinone (TOKYO CHEMICAL)

[0236]

[0237] Example 1

[0238] The surface-modified green quantum dots, a photocurable monomer with an unsaturated double bond, and a thermosetting monomer are mixed and stirred at room temperature for 12 hours. A polymerization inhibitor is added and stirred at room temperature for 5 minutes. A photopolymerization initiator is then added, followed by a light-scattering agent, and the mixture is mixed to produce a solvent-free quantum dot composition.

[0239]

[0240] Examples 2 to 7 and Comparative Examples 1 to 4

[0241] A quantum dot composition is manufactured in the same manner as in Example 1, except that the content of each component is changed as shown in Table 2 below.

[0242]

[0243] The content of each component based on the solid content of the quantum dot composition manufactured in the examples and comparative examples is as shown in Table 2 below.

[0244] The properties of the manufactured quantum dot composition were evaluated in Table 2 below, and the results are shown in Table 2 below.

[0245] (1) Viscosity (unit: cps): For each quantum dot composition, the viscosity value was measured at 25°C using a viscometer (Brookfield DV-Ⅱ, RV-2 spindle, 23 rpm).

[0246] (2) EQE (external quantum efficiency, unit: %): Each quantum dot composition corresponding to the examples and comparative examples was applied to a thickness of 15 μm on yellow photoresist (YPR) using a spin coater (Mikasa, opticoat MS-A150, 830 rpm, 5 seconds), and exposed to 5000 mJ / cm2 in an exposure device (wavelength 395 nm) under a nitrogen atmosphere. 2 Afterwards, EQE was measured for a single film (2 cm x 2 cm) of the manufactured specimen using an integral hemisphere quantum efficiency meter (Otsuka, QE-2000).

[0247] Afterwards, the above-mentioned single film was cured (POB) in a nitrogen atmosphere at 180°C for 30 minutes, and then cooled for 1 hour. EQE was measured using the same method as above.

[0248] Afterwards, curing (CVD) was performed in air at 200°C for 5 minutes, and then cooling was performed for 1 hour. EQE was measured using the same method as above.

[0249] The retention rate was calculated as the percentage of the EQE measured in CVD relative to the EQE measured after exposure. A higher retention rate indicates that the light efficiency of the cured film formed from the quantum dot composition did not decrease.

[0250] Example 1234567 Quantum dot Chemical formula 1-1080706050403020 Chemical formula 2-120304050607080 Content 4141414141414141 Photocurable monomer 49.9549.9549.9549.9549.9549.9549.95 Thermocurable monomer 4444444 Photopolymerization initiator 1111111 Light scattering agent 4444444 Polymerization inhibitor 0.050.050.050.050.050.050.050.05 Total 100100100100100100 Viscosity (cps) 23.724.324.825.125.525.926.8 EQE (%) Exposure After 30.030.029.929.829.829.729.6POB30.130.130.030.030.029.929.9CVD29.629.829.829.930.130.330.2Maintenance rate9899100100101102102

[0251] Comparative Example 1234 Quantum Dot Chemical Formula 1-10 100 50 500 Chemical Formula 2-10 50 50 100 Content 4 14 14 141 Photocurable Monomer 5 3.95 5 3.45 5 3.45 4 2.95 Thermosetting Monomer 0 0.5 114 Photopolymerization Initiator 1 111 Light Scattering Agent 4 4 4 Polymerization Inhibitor 0.05 0.05 0.05 0.05 Total 100 100 100 Viscosity (cps) 23.2 24.8 29.8 27.8 EQE (%) After Exposure 30.2 29.8 29.5 29.3 POB 30.2 29.7 29.4 28.6 CVD 29.2 29.3 29.5 28.4 Retention Rate 9 7 9 8 10 0 97

[0252]

[0253] According to Table 2 above, the quantum dot composition of the example has a low decrease in quantum efficiency of the quantum dot even after undergoing a subsequent process after photocuring, thereby increasing the external quantum efficiency of the quantum dot and thus improving the reliability of the display device. In addition, even if a thermosetting monomer is included, the viscosity does not increase excessively, thereby enabling inkjet jetting (printing), thereby improving the processability.

[0254] On the other hand, according to Table 3 above, Comparative Example 1 showed a significantly lower EQE value after CVD exposure. This proves that the retention rate value can be improved by adding chemical formula 2-1 and a thermosetting monomer in an appropriate ratio as in the example. Compared to Example 4, even when chemical formulas 1-10 and 2-1 were mixed in the same ratio of 50:50 as in Comparative Example 2, the retention rate was not improved unless the thermosetting monomer was sufficiently added. Compared to Example 4, when an excessive amount of thermosetting monomer was added as in Comparative Example 3, the viscosity increased, exceeding the upper limit of the viscosity (27 cps) for inkjet jetting, and the post-exposure efficiency decreased, so that even if the retention rate was high, the final efficiency, i.e., the CVD efficiency, had a relatively low value. As in Comparative Example 4, when the compound of Chemical Formula 1-10 is not added, the compound of Chemical Formula 2-1 is excessively desorbed during the thermal process, and the number of ligands required for passivation of the quantum dot surface decreases, and the retention rate actually decreases, and the viscosity also makes inkjet jetting impossible.

[0255]

[0256] Examples 8 to 11

[0257] A quantum dot composition is manufactured in the same manner as in Example 4, except that the content of each component is changed as shown in Table 4 below.

[0258]

[0259] Examples 12 to 15

[0260] A quantum dot composition is manufactured in the same manner as in Example 5, except that the content of each component is changed as shown in Tables 4 and 5 below.

[0261]

[0262] Examples 16 to 19

[0263] A quantum dot composition is manufactured in the same manner as in Example 6, except that the content of each component is changed as shown in Tables 4 and 5 below.

[0264]

[0265] The manufactured quantum dot composition was evaluated in the same manner as above, and the results are shown in Tables 4 and 5 below.

[0266] Example 8910111213Quantum dot414141414141Photocurable monomer46.9548.9550.9552.9546.9548.95Thermocurable monomer753175Photopolymerization initiator111111Light scattering agent444444Polymerization inhibitor0.050.050.050.050.050.050.05Total100100100100100100Viscosity25.125.125.125.125.525.5EQE(%)Exposure Post29.829.930.030.129.830.0POB30.030.130.130.030.030.1CVD29.929.929.829.530.130.1Maintenance1001009998101100

[0267]

[0268] Example 141516171819Quantum dot 41414141414141Photocurable monomer 50.9552.9546.9548.9550.9552.95Thermocurable monomer 317531Photopolymerization initiator 111111Light scattering agent 444444Polymerization inhibitor 0.050.050.050.050.050.050.05Total 100100100100100100Viscosity 25.525.525.925.925.9EQE(%)Exposure Post 30.130.129.729.729.930.0POB30.230.329.930.030.029.9CVD30.129.630.330.230.129.6Maintenance rate1009810210210199

[0269]

[0270] As shown in Tables 4 and 5 above, all examples have a viscosity of 28 cps or less, preferably 26 cps or less, which allows inkjet jetting, and thus can be applied to the process without any problems. In particular, Examples 12, 13, 14, 15, 17, and 18 have a retention rate of 100% or more and an EQE value of 30% or more after CVD, making them optimal quantum dot compositions.

[0271] It is believed that optimal efficiency can be achieved when the ratio of the compound of chemical formula 1-10 to the compound of chemical formula 2-1 is adjusted to 50:50 to 30:70, and the thermosetting monomer is added at 3 to 7% of the total ink content.

[0272]

[0273] Simple modifications or changes of the present invention can be easily implemented by a person having ordinary skill in the art, and all such modifications or changes can be considered to be included in the scope of the present invention.

Claims

1. As a quantum dot composition, A quantum dot having two different ligands; a photocurable monomer having an unsaturated double bond; a thermosetting monomer; and an initiator. The above thermosetting monomer includes an oxetane monomer, A quantum dot composition, wherein the thermosetting monomer is included in an amount of 1 to 10 wt% of the composition.

2. A quantum dot composition according to claim 1, wherein the oxetane monomer comprises at least 95 wt% of the thermosetting monomer.

3. A quantum dot composition according to claim 1, wherein the oxetane-based monomer comprises at least one of 1,4-bis[(3-ethyl-3-oxetanyl methoxy)methyl]benzene, 1,4-bis[(3-methyl-3-oxetanyl methoxy)methyl]benzene, 3-methyl-3-glycidyl oxetane, 3-ethyl-3-glycidyl oxetane, bis[1-ethyl(3-oxetanyl)]methyl ether, 3-ethyl-3-hydroxymethyl oxetane, 3-ethyl-3-[(3-ethoxyoxetan-3-yl)methoxy] oxetane, 3-ethyl-3-phenoxymethyl oxetane, 3-ethyl-3-[(2-ethylhexyloxy)methyl] oxetane, oxetanyl-silicate, and phenol novolak oxetane.

4. A quantum dot composition in the first paragraph, wherein the quantum dot is surface-modified with a mixture containing a first modifying material and a second modifying material, and the ligand is derived from the first modifying material and the second modifying material.

5. A quantum dot composition in the fourth paragraph, wherein the first modifying material is a curable modifying material having a carboxylic acid group, and the second modifying material is a modifying material having one or more thiol groups.

6. A quantum dot composition in the fifth paragraph, wherein the first modifying material and the second modifying material in the mixture are included in a weight ratio of 80:20 to 20:80 out of a total of 100 parts by weight.

7. A quantum dot composition in paragraph 5, wherein the total of the first modifying material and the second modifying material is comprised at least 95 wt% of the mixture.

8. In paragraph 5, the first modified material includes at least one compound represented by the following chemical formula 1: [Chemical Formula 1] (In the above chemical formula 1, R 1 is a substituted or unsubstituted C1 to C10 alkyl group or a substituted or unsubstituted C6 to C20 aryl group, L 11 Inland L 13 are each independently a substituted or unsubstituted C1 to C10 alkylene group, ester group or ether group, n is an integer from 1 to 20, except that L 12 It is an ester group and at the same time L 13 When this is an unsubstituted C1 to C10 alkylene group, n is an integer from 4 to 20), The second modified material is a quantum dot composition comprising at least one compound represented by the following chemical formula 2: [Chemical Formula 2] (In the above chemical formula 2, R 2 is a substituted or unsubstituted C2 to C10 alkenyl group, L 21 Inland L 23 are each independently a single bond, a substituted or unsubstituted C1 to C10 alkylene group, an ester group or an ether group, m is an integer from 1 to 10).

9. In the first paragraph, the composition 10 to 60 wt% of the above quantum dots; 30 to 70 wt% of a photocurable monomer having the above unsaturated double bond; 1 to 10 wt% of the thermosetting monomer; and A quantum dot composition comprising 0.1 to 5 wt% of the above initiator.

10. A quantum dot composition according to claim 1, wherein the composition is a solvent-free composition.

11. A quantum dot composition according to claim 1, wherein the composition further comprises at least one of a light scattering agent and a polymerization inhibitor.

12. A quantum dot composition according to claim 1, wherein the quantum dot composition has a viscosity of 5 to 27 cps at 25°C.

13. A quantum dot composition in accordance with claim 1, wherein the specimen manufactured with the quantum dot composition has an external quantum efficiency (EQE) of 29.9% or more after being cured (POB) in a nitrogen atmosphere at 180°C for 30 minutes.

14. A quantum dot composition in paragraph 1, wherein a specimen manufactured with the quantum dot composition is cured (POB) in a nitrogen atmosphere at 180°C for 30 minutes and then cured (CVD) in air at 200°C for 5 minutes, and then has an external quantum efficiency of 29.5% or more.

15. A cured film comprising a cured product of the quantum dot composition of any one of claims 1 to 14.

16. A display device including the cured film of Article 15.

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