Photoconversion curable composition, cured film comprising photoconversion curable composition, and image display device comprising cured film

Abstract

The present invention relates to a photoconversion curable composition, a cured film comprising the photoconversion curable composition, and an image display device comprising the cured film. The curable composition of the present invention uses cross-linking ligands surface-modified on quantum dots to enable surface uniformity of a coating film and low viscosity to be implemented, and the curable composition is used to improve thermal stability of a thin film.

Description

A photoconversion curable composition, a cured film comprising the photoconversion curable composition, and an image display device comprising the cured film

[0001] The present invention relates to a photoconversion curable composition, a cured film comprising the photoconversion curable composition, and an image display device comprising the cured film.

[0002] Quantum dots are nanometer-sized semiconductor nanocrystals whose energy band gap (Eg) varies depending on their size and shape. These quantum dots, thanks to the quantum confinement effect, allow for the control of their emission wavelength simply by adjusting their size. Furthermore, they exhibit excellent color purity and high photoluminescence (PL) efficiency, attracting significant interest not only in displays but also in lighting sources, solar cells, semiconductor lasers / optical amplifiers, and bioimaging.

[0003] Meanwhile, color filters, used in liquid crystal displays and optical filters for cameras, are manufactured by coating fine areas colored in three or more colors onto a solid-state imaging element or transparent substrate. Such colored thin films can typically be formed by dyeing, printing, pigment dispersion, inkjet, or other methods.

[0004] Among them, the pigment dispersion method is a method of forming a colored thin film by repeating a series of processes of coating, exposing, developing, and thermally curing a photopolymerizable composition containing a coloring agent on a transparent substrate provided with a black matrix. For example, Korean Patent Publication No. 1992-7002502 proposes a method for producing a colored photosensitive resin composition using the pigment dispersion method. However, the method requires coating, exposing, developing, and curing processes for red, green, and blue, respectively, to form pixels, which makes the manufacturing process very long and increases the number of control factors between processes, making it difficult to manage yield.

[0005] To address these challenges, ongoing efforts have been made to replace pigments with quantum dots, leading to their application in various display devices, electronic devices, and more. However, further research is needed to develop compositions that can stabilize quantum dots to improve processability and performance.

[0006] Quantum dots are formed by weakly bonding organic ligands to an inorganic surface. The surface is not protected by strong bonds such as covalent bonds, which reduces efficiency when applied to thin film formation and photoconversion devices. In particular, the thin film manufacturing process inevitably involves a high heat treatment process of 60°C to 300°C, and the heat generated during this process reduces the color conversion efficiency (PCE) of the quantum dots and causes ligand detachment. This significantly reduces the stability of the quantum dots.

[0007] Against this backdrop, the inventors of the present invention have conducted research efforts to develop quantum dots with excellent stability and improved performance, and have completed the present invention by manufacturing quantum dots modified with a cross-linking ligand on the surface.

[0008] [Prior Art Literature]

[0009] [Patent Document]

[0010] (Patent Document 001) Korean Patent Publication No. 1992-7002502

[0011] The present invention aims to solve the above-mentioned problems and other problems related thereto.

[0012] One exemplary object of the present invention is to provide a curable composition comprising quantum dots having improved ink resistance and thermal stability.

[0013] Another exemplary object of the present invention is to provide a cured film comprising the curable composition and an image display device.

[0014] The technical problem to be achieved according to the technical idea of ​​the invention disclosed in this specification is not limited to the problem to solve the above-mentioned problem, and other problems not mentioned will be clearly understood by those skilled in the art from the description below.

[0015] As one aspect for achieving the above purpose, one example of the present invention is

[0016] Quantum dots surface-modified with a compound represented by any one of the following chemical formulae 1 to 4; and

[0017] [Chemical Formula 1]

[0018]

[0019] [Chemical Formula 2]

[0020]

[0021] [Chemical Formula 3]

[0022]

[0023] [Chemical Formula 4]

[0024]

[0025] A curable composition comprising a photopolymerizable monomer comprising at least one of the compounds represented by the following chemical formulae 5 and 6:

[0026] [Chemical Formula 5]

[0027]

[0028] [Chemical Formula 6]

[0029]

[0030] In the above chemical formulas 1 to 6,

[0031] R1 and R2 are the same or different and each independently represent hydrogen, an acryl group, a cyano group, a nitro group, C1~C 40 Alkyl group of C2~C 40 Alkenyl group, C2~C 40 Alkynyl group, C6~C40 Selected from the group consisting of an aryl group and a heteroaryl group having 5 to 40 nuclear atoms,

[0032] The above A is C, O, S or N,

[0033] The above X is C1~C 40 alkylene group, C1~C 40 Cycloalkylene group, C1~C 40 Alkyloxylene group, C6~C 40 An arylene group or a heteroarylene group having 5 to 40 nuclear atoms,

[0034] The above Y is C1~C 40 Alkyl group or C6~C 40 is an aryl group,

[0035] The above Z is hydrogen or C,

[0036] In the above chemical formulas 1 to 4, n is an integer from 1 to 30,

[0037] In the above chemical formulas 5 and 6, n is an integer from 0 to 12,

[0038] In the above chemical formula 6, m is an integer from 0 to 2,

[0039] Acrylic groups of the above X, Y, R1 and R2, C1~C 40 Alkyl group of C2~C 40 Alkenyl group, C2~C 40 Alkynyl group, C6~C 40 Aryl group of, heteroaryl group having 5 to 40 nuclear atoms, C1~C 40 alkylene group, C1~C 40 Cycloalkylene group, C1~C 40 Alkyloxylene group, C6~C 40 The arylene group and the heteroarylene group having 5 to 40 nuclear atoms are each independently selected from the group consisting of halogen, cyano group, nitro group, C1~C 40 Alkyl group of C2~C 40 Alkenyl group, C2~C 40 Alkynyl group, C3~C 40 Cycloalkyl group of C1~C 40Alkyloxy group, C6~C 60 Aryloxy group, C6~C 60 It may be substituted with one or more substituents selected from the group consisting of an aryl group and a heteroaryl group having 5 to 40 nuclear atoms, and in this case, when there are multiple substituents, they may be the same or different from each other.

[0040] Another example of the present invention provides a cured film comprising the curable composition.

[0041] Another example of the present invention provides an image display device including the cured film.

[0042] As one aspect for achieving the above purpose, one example of the present invention is

[0043] Quantum dots surface-modified with a compound represented by any one of the following chemical formulae 1 to 4; and

[0044] [Chemical Formula 1]

[0045]

[0046] [Chemical Formula 2]

[0047]

[0048] [Chemical Formula 3]

[0049]

[0050] [Chemical Formula 4]

[0051]

[0052] A curable composition comprising a photopolymerizable monomer comprising at least one of the compounds represented by the following chemical formulae 5 and 6:

[0053] [Chemical Formula 5]

[0054]

[0055] [Chemical Formula 6]

[0056]

[0057] In the above chemical formulas 1 to 6,

[0058] R1 and R2 are the same or different and each independently represent hydrogen, an acryl group, a cyano group, a nitro group, C1~C 40 Alkyl group of C2~C 40 Alkenyl group, C2~C 40 Alkynyl group, C6~C 40 Selected from the group consisting of an aryl group and a heteroaryl group having 5 to 40 nuclear atoms,

[0059] The above A is C, O, S or N,

[0060] The above X is C1~C 40 alkylene group, C1~C 40 Cycloalkylene group, C1~C 40 Alkyloxylene group, C6~C 40 An arylene group or a heteroarylene group having 5 to 40 nuclear atoms,

[0061] The above Y is C1~C 40 Alkyl group or C6~C 40 is an aryl group,

[0062] The above Z is hydrogen or C,

[0063] In the above chemical formulas 1 to 4, n is an integer from 1 to 30,

[0064] In the above chemical formulas 5 and 6, n is an integer from 0 to 12,

[0065] In the above chemical formula 6, m is an integer from 0 to 2,

[0066] Acrylic groups of the above X, Y, R1 and R2, C1~C 40 Alkyl group of C2~C 40 Alkenyl group, C2~C 40 Alkynyl group, C6~C 40 Aryl group of, heteroaryl group having 5 to 40 nuclear atoms, C1~C 40 alkylene group, C1~C 40 Cycloalkylene group, C1~C 40 Alkyloxylene group, C6~C 40The arylene group and the heteroarylene group having 5 to 40 nuclear atoms are each independently selected from the group consisting of halogen, cyano group, nitro group, C1~C 40 Alkyl group of C2~C 40 Alkenyl group, C2~C 40 Alkynyl group, C3~C 40 Cycloalkyl group of C1~C 40 Alkyloxy group, C6~C 60 Aryloxy group, C6~C 60 It may be substituted with one or more substituents selected from the group consisting of an aryl group and a heteroaryl group having 5 to 40 nuclear atoms, and in this case, when there are multiple substituents, they may be the same or different from each other.

[0067] Another example of the present invention provides a cured film comprising the curable composition.

[0068] Another example of the present invention provides an image display device including the cured film.

[0069] Figure 1 shows the results of confirming the degree of crosslinking of a single film manufactured using a curable composition according to an example of the present invention by measuring it using an infrared spectroscopy (FT-IR).

[0070] The present invention is specifically described as follows.

[0071] Meanwhile, each description and embodiment disclosed in this application can also be applied to each other description and embodiment. In other words, all combinations of the various elements disclosed in this application fall within the scope of this application. Furthermore, the scope of this application is not limited by the specific descriptions described below.

[0072] As one aspect for achieving the above purpose, the present invention

[0073] Quantum dots surface-modified with a compound represented by any one of the following chemical formulae 1 to 4; and

[0074] [Chemical Formula 1]

[0075]

[0076] [Chemical Formula 2]

[0077]

[0078] [Chemical Formula 3]

[0079]

[0080] [Chemical Formula 4]

[0081]

[0082] A curable composition comprising a photopolymerizable monomer comprising at least one of the compounds represented by the following chemical formulae 5 and 6 is provided.

[0083] [Chemical Formula 5]

[0084]

[0085] [Chemical Formula 6]

[0086]

[0087] In the above chemical formulas 1 to 6,

[0088] R1 and R2 are the same or different and each independently represent hydrogen, an acryl group, a cyano group, a nitro group, C1~C 40 Alkyl group of C2~C 40 Alkenyl group, C2~C 40 Alkynyl group, C6~C 40 Selected from the group consisting of an aryl group and a heteroaryl group having 5 to 40 nuclear atoms,

[0089] The above A is C, O, S or N,

[0090] The above X is C1~C 40 alkylene group, C1~C 40 Cycloalkylene group, C1~C 40 Alkyloxylene group, C6~C 40 An arylene group or a heteroarylene group having 5 to 40 nuclear atoms,

[0091] The above Y is C1~C 40 Alkyl group or C6~C 40is an aryl group,

[0092] The above Z is hydrogen or C,

[0093] In the above chemical formulas 1 to 4, n is an integer from 1 to 30,

[0094] In the above chemical formulas 5 and 6, n is an integer from 0 to 12,

[0095] In the above chemical formula 6, m is an integer from 0 to 2,

[0096] Acrylic groups of the above X, Y, R1 and R2, C1~C 40 Alkyl group of C2~C 40 Alkenyl group, C2~C 40 Alkynyl group, C6~C 40 Aryl group of, heteroaryl group having 5 to 40 nuclear atoms, C1~C 40 alkylene group, C1~C 40 Cycloalkylene group, C1~C 40 Alkyloxylene group, C6~C 40 The arylene group and the heteroarylene group having 5 to 40 nuclear atoms are each independently selected from the group consisting of halogen, cyano group, nitro group, C1~C 40 Alkyl group of C2~C 40 Alkenyl group, C2~C 40 Alkynyl group, C3~C 40 Cycloalkyl group of C1~C 40 Alkyloxy group, C6~C 60 Aryloxy group, C6~C 60 It may be substituted with one or more substituents selected from the group consisting of an aryl group and a heteroaryl group having 5 to 40 nuclear atoms, and in this case, when there are multiple substituents, they may be the same or different from each other.

[0097]

[0098] [quantum dot]

[0099] In the present invention, the term "quantum dot" refers to a nanocrystal exhibiting quantum confinement or exciton confinement, and is a type of nanostructure that is luminescent (e.g., capable of emitting light upon energy excitation). The term "quantum dot" herein is not limited in shape unless specifically defined.

[0100] The above nanostructure refers to a structure having a single region or characteristic dimension with nanoscale dimensions. The nanostructure may have any shape, such as a nanowire, nanorod, nanotube, multi-pod type shape with two or more pods, nanodot (or quantum dot), etc., and is not particularly limited thereto.

[0101] The electrical and / or optical properties of the quantum dots of the present invention may vary depending on their physical properties (e.g., composition, size, and / or shape). For example, quantum dots may have a large surface area per unit volume, exhibit quantum confinement effects, and exhibit properties different from those of bulk materials of the same composition.

[0102] In the present invention, the type of the quantum dot is not particularly limited and includes all known or commercially available quantum dots.

[0103] In one embodiment of the present invention, the quantum dot comprises InP, CdSe, AgInGaS, ZnSeTe, CdTe, ZnS, ZnSe, ZnTe, ZnO, HgS, HgSe, HgTe, MgSe, MgS, CdSeS, CdSeTe, CdSTe, ZnSeS, ZnSTe, HgSeS, HgSeTe, HgSTe, CdZnS, CdZnSe, CdZnTe, CdHgS, CdHgSe, CdHgTe, HgZnS, HgZnSe, HgZnTe, MgZnSe, MgZnS, ZnSeSTe, HgZnTeS, CdZnSeS, CdZnSeTe, CdZnSTe, CdHgSeS, CdHgSeTe, CdHgSTe, HgZnSeS, HgZnSeTe, It can be selected from the group consisting of HgZnSTe and mixtures thereof.

[0104] Quantum dots are formed by weakly bonding organic ligands to an inorganic surface. Their surfaces are not protected by strong bonds, such as covalent bonds. This reduces their efficiency when applied to thin film formation and photoconversion devices. In particular, the heat generated during the heat treatment process in the thin film manufacturing process can significantly reduce the color conversion efficiency (PCE) of quantum dots and cause ligand detachment, significantly reducing their stability. Therefore, improving thermal stability is necessary.

[0105]

[0106] [Ligand]

[0107] In the present invention, the quantum dot is surface-modified with a compound represented by any one of the following chemical formulas 1 to 4.

[0108] [Chemical Formula 1]

[0109]

[0110] [Chemical Formula 2]

[0111]

[0112] [Chemical Formula 3]

[0113]

[0114] [Chemical Formula 4]

[0115]

[0116] In the above chemical formulas 1 to 4,

[0117] R1 and R2 are the same or different and each independently represent hydrogen, an acryl group, a cyano group, a nitro group, C1~C 40 Alkyl group of C2~C 40 Alkenyl group, C2~C 40 Alkynyl group, C6~C 40 Selected from the group consisting of an aryl group and a heteroaryl group having 5 to 40 nuclear atoms,

[0118] The above Z is hydrogen or C,

[0119] n is an integer from 1 to 30.

[0120] Acrylic groups of the above R1 and R2, C1~C 40 Alkyl group of C2~C 40 Alkenyl group, C2~C 40 Alkynyl group, C6~C 40 Aryl group of, heteroaryl group having 5 to 40 nuclear atoms, C1~C 40 alkylene group, C1~C 40 Cycloalkylene group, C1~C 40 Alkyloxylene group, C6~C 40 The arylene group and the heteroarylene group having 5 to 40 nuclear atoms are each independently selected from the group consisting of halogen, cyano group, nitro group, C1~C 40 Alkyl group of C2~C 40 Alkenyl group, C2~C 40 Alkynyl group, C3~C 40 Cycloalkyl group of C1~C 40 Alkyloxy group, C6~C 60 Aryloxy group, C6~C 60 It may be substituted with one or more substituents selected from the group consisting of an aryl group and a heteroaryl group having 5 to 40 nuclear atoms, and in this case, when there are multiple substituents, they may be the same or different from each other.

[0121] In the present invention, "alkyl" means a monovalent substituent derived from a straight or branched saturated hydrocarbon having 1 to 40 carbon atoms. Examples of such alkyl include, but are not limited to, methyl, ethyl, propyl, isobutyl, sec-butyl, pentyl, iso-amyl, hexyl, etc.

[0122] In the present invention, "alkenyl" means a monovalent substituent derived from a straight or branched unsaturated hydrocarbon having 2 to 40 carbon atoms and at least one carbon-carbon double bond. Examples of such alkenyl include, but are not limited to, vinyl, allyl, isopropenyl, and 2-butenyl.

[0123] In the present invention, "alkynyl" means a monovalent substituent derived from an unsaturated hydrocarbon having 2 to 40 carbon atoms and a straight or branched chain having at least one carbon-carbon triple bond. Examples of such alkynyl include, but are not limited to, ethynyl and 2-propynyl.

[0124] In the present invention, "aryl" refers to a monovalent substituent derived from an aromatic hydrocarbon having 6 to 60 carbon atoms, which is a single ring or a combination of two or more rings. Furthermore, forms in which two or more rings are simply attached to each other (pendant) or condensed may also be included. Examples of such aryls include, but are not limited to, phenyl, naphthyl, phenanthryl, and anthryl.

[0125] In the present invention, "cycloalkyl" refers to a monovalent substituent derived from a monocyclic or polycyclic non-aromatic hydrocarbon having 3 to 40 carbon atoms. Examples of such cycloalkyl include, but are not limited to, cyclopropyl, cyclopentyl, cyclohexyl, norbornyl, and adamantine.

[0126] In the present invention, "heteroaryl" refers to a monovalent substituent derived from a monoheterocyclic or polyheterocyclic aromatic hydrocarbon having 5 to 60 nuclear atoms. At this time, at least one carbon atom in the ring, preferably 1 to 3 carbon atom, is substituted with a heteroatom such as N, O, S, or Se. In addition, a form in which two or more rings are simply attached to each other (pendant) or condensed may be included, and a form condensed with an aryl group may also be included. Examples of such heteroaryls include, but are not limited to, 6-membered monocyclic rings such as pyridyl, pyrazinyl, pyrimidinyl, pyridazinyl, and triazinyl; polycyclic rings such as phenoxathienyl, indolizinyl, indolyl, purinyl, quinolyl, benzothiazole, and carbazolyl; and 2-furanyl, N-imidazolyl, 2-isoxazolyl, 2-pyridinyl, and 2-pyrimidinyl.

[0127] In the present invention, "alkyloxy" is a monovalent substituent represented by R'O-, wherein R' means alkyl having 1 to 40 carbon atoms. Such alkyloxy may include a linear, branched, or cyclic structure. Examples of such alkyloxy include, but are not limited to, methoxy, ethoxy, n-propoxy, 1-propoxy, t-butoxy, n-butoxy, and pentoxy.

[0128] In the present invention, "aryloxy" is a monovalent substituent represented by RO-, wherein R represents aryl having 6 to 60 carbon atoms. Examples of such aryloxy include, but are not limited to, phenyloxy, naphthyloxy, and diphenyloxy.

[0129] In this way, the ligand used to modify the surface of the quantum dot in the present invention is bonded to the surface of the quantum dot and crosslinks with the photopolymerizable monomer to form a polymer, thereby stabilizing the surface of the quantum dot and improving the degree of crosslinking, thereby improving the thermal stability and surface uniformity of a thin film manufactured using the curable composition including the quantum dot.

[0130] In one embodiment of the present invention, the compound represented by any one of the chemical formulas 1 to 4 may have a carboxyl group or an amine group at a terminal and a photopolymerizable monomer bonded to the other terminal.

[0131] In one embodiment of the present invention, the compounds represented by the chemical formulae 1, 3 and 4 may each be represented by the following structures.

[0132] For chemical formula 1:

[0133] or

[0134] For chemical formula 3:

[0135]

[0136] For chemical formula 4:

[0137]

[0138] In the present invention, the compound represented by any one of the chemical formulas 1 to 4 may be included in an amount of 0.1 part by weight or more, 0.5 part by weight or more, 1 part by weight or more, 3 parts by weight or more, 5 parts by weight or more, or 7 parts by weight or more, based on 100 parts by weight of the total curable composition.

[0139] In the present invention, the compound represented by any one of the chemical formulas 1 to 4 may be included in an amount of 20 parts by weight or less, 15 parts by weight or less, 10 parts by weight or less, 7 parts by weight or less, 5 parts by weight or less, or 3 parts by weight or less, based on 100 parts by weight of the total curable composition.

[0140]

[0141] [Photopolymerizable monomer]

[0142] In the present invention, the curable composition comprises at least one photopolymerizable monomer among the compounds represented by chemical formulae 5 and 6.

[0143] [Chemical Formula 5]

[0144]

[0145] [Chemical Formula 6]

[0146]

[0147] The curable composition according to the present invention is characterized by being a solvent-free type that does not contain a solvent. To implement such a solvent-free type composition, by using a monomer comprising a compound represented by the above chemical formulas 5 and / or 6, not only can quantum dots be excellently dispersed, but also problems such as reduced jetting properties and poor film properties caused by the inclusion of a solvent can be improved.

[0148] In the present invention, the compound represented by the chemical formula 5 may include two or more (meth)acrylate groups, and the compound represented by the chemical formula 6 may include one or more (meth)acrylate groups.

[0149] In one embodiment of the present invention, Y may be substituted with one of the following structural formulas.

[0150]

[0151] At this time, * indicates the site that combines with Y.

[0152] In one embodiment of the present invention, the compound represented by the chemical formula 5 may be selected from the group consisting of A-1 to A-9 below.

[0153]

[0154] In one embodiment of the present invention, the compound represented by the chemical formula 6 may be selected from the group consisting of B-1 to B-8 below.

[0155]

[0156] [etc]

[0157] In the present invention, the curable composition may further include a photopolymerization initiator, a light scattering agent, or a combination thereof.

[0158] The type of the photopolymerization initiator is not particularly limited, and may include, for example, a triazine compound, an acetophenone compound, a benzophenone compound, a thioxanthone compound, a benzoin compound, an oxime ester compound, an aminoketone compound, a phosphine or phosphine oxide compound, a carbazole compound, a diketone compound, a sulfonium borate compound, a diazo compound, a biimidazole compound, or a combination thereof.

[0159] 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.

[0160] 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.

[0161] 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.

[0162] Examples of the above thioxanthone compounds include thioxanthone, 2-methylthioxanthone, isopropyl thioxanthone, 2,4-diethyl thioxanthone, 2,4-diisopropyl thioxanthone, 2-chlorothioxanthone, etc.

[0163] Examples of the above benzoin compounds include benzoin, benzoin methyl ether, benzoin ethyl ether, benzoin isopropyl ether, benzoin isobutyl ether, benzyldimethyl ketal, etc.

[0164] In the above composition, the content of the photopolymerization initiator can be appropriately adjusted in consideration of the type and content of the photopolymerizable monomer used.

[0165] In one embodiment, the content of the photopolymerizable initiator may be 0.01 wt% or more, 0.1 wt% or more, 0.5 wt% or more, or 1 wt% or more, based on 100 wt% of the total composition. The content of the photopolymerizable initiator may be 10 wt% or less, or 5 wt% or less, based on the total weight of the composition, but is not limited thereto.

[0166] The type of the above light scattering agent is not particularly limited, and may include, for example, barium sulfate (BaSO4), calcium carbonate (CaCO3), titanium dioxide (TiO2), zirconia (ZrO2), or a combination thereof.

[0167] The light-scattering agent reflects light that is not absorbed by the 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 curable composition.

[0168] The form of use of the above light scattering agent is not particularly limited, and for example, a form of dispersion dispersed in a solvent can be used to ensure dispersion stability in a curable composition.

[0169] In the above composition, the content of the light-scattering agent can be appropriately adjusted as needed.

[0170] In one embodiment, the content of the light-scattering agent may be 0.1 wt% or more, 0.5 wt% or more, 1 wt% or more, or 5 wt% or more, based on 100 wt% of the total weight of the composition. The content of the light-scattering agent may be 10 wt% or less, or 5 wt% or less, based on the total weight of the composition, but is not limited thereto.

[0171] When the above light scattering agent is included in the above content range, an effect of improving the light conversion efficiency by using the light scattering agent can be expected, and the pattern characteristics can also be improved.

[0172] In the present invention, the curable composition may further include at least one selected from the group consisting of a binder resin and a solvent.

[0173] The above binder resin may include an acrylic binder resin, a cardo binder resin, or a combination thereof.

[0174] Specific examples of the above acrylic binder resin include, but are not limited to, (meth)acrylic acid / benzyl methacrylate copolymer, (meth)acrylic acid / benzyl methacrylate / styrene copolymer, (meth)acrylic acid / benzyl methacrylate / 2-hydroxyethyl methacrylate copolymer, (meth)acrylic acid / benzyl methacrylate / styrene / 2-hydroxyethyl methacrylate copolymer, etc., and these may be used alone or in combination of two or more.

[0175] In the present invention, the solvent may include propylene glycol monomethyl ether acetate, dipropylene glycol methyl ether acetate, cyclohexyl acetate, ethanol, ethylene glycol dimethyl ether, ethylene glycol butyl ether acetate, ethylene diglycol methyl ethyl ether, diethylene glycol dimethyl ether, dimethyl acetamide, dimethyl adipate, cyclohexylacrylate, hydroxyethyl acrylate, 2-butoxyethanol, N-methylpyrrolidine, N-ethylpyrrolidine, propylene carbonate, γ-butyrolactone, acetone, or a combination thereof.

[0176] As another aspect for achieving the above object, the present invention provides a cured film comprising the curable composition and an image display device comprising the cured film.

[0177]

[0178] Hereinafter, the present invention will be described in more detail through the following examples. However, these examples are intended to exemplify the present invention and the scope of the present invention is not limited to these examples.

[0179]

[0180] [quantum dot]

[0181] InP / ZnSe / ZnS (Nanosys, hereinafter referred to as 'QD-1') or Ag / In / Ga / S (Nanosys, hereinafter referred to as 'QD-2') were prepared as quantum dots. QD-1 is an InP core-based green QD, has a size of 537 nm and a half width of 35 nm. QD-2 is an Ag / In / Ga / S core-based green QD, has a size of 530 nm and a half width of 30 nm. The above QD-1 and QD-2 were each prepared by dispersing them in toluene at a concentration of 30 wt%.

[0182]

[0183] [Examples 1 and 2]

[0184] To the prepared QD-1 quantum dots, monomers 1,6-hexanediol diacrylate (HDDA, denoted as MN-1, Sigma-Aldrich) and benzyl acrylate (BZA, denoted as MN-2, Sigma-Aldrich) were applied, and 2 wt% (Example 1) or 5 wt% (Example 2) of mono-2-(methacryloyloxy)ethyl succinate (MMES) was added as a surface stabilizing additive. In addition, TPO (TCI) as a photopolymerization initiator (denoted as PI-1), TiO2 (in HDDA) as a light-scattering particle (denoted as SP-1) and BYK-111 dispersant, and BYK-2013 as an ink composition dispersion stabilizer were mixed in the weight% of Table 1 to prepare a curable composition. The structures of MMES, TPO, HDDA, and BZA used are as follows.

[0185]

[0186]

[0187]

[0188] [Examples 3 and 4]

[0189] A curable composition was prepared using the same process as in Examples 1 and 2, except that 2 wt% (Example 3) or 5 wt% (Example 4) of 2-carboxyethyl acrylate (CA) was used as a surface stabilizing additive.

[0190] The structure of the CA used is as follows.

[0191]

[0192]

[0193] [Examples 5 and 6]

[0194] Curable compositions were prepared using the same process as in Examples 1 and 2, except that QD-2 quantum dots were applied and 2 wt% (Example 5) or 5 wt% (Example 6) of 2-Aminoethyl methacrylate (AA) was used as a surface stabilizing additive.

[0195] The structure of the AA used is as follows.

[0196]

[0197]

[0198] [Examples 7 and 8]

[0199] A curable composition was prepared using the same process as in Examples 5 and 6, except that 2 wt% (Example 7) or 5 wt% (Example 8) of 2-(Dimethylamino)ethyl methacrylate (DMAEMA) was used as a surface stabilizing additive.

[0200] The structure of DMAEMA used is as follows.

[0201]

[0202]

[0203] [Comparative Example 1]

[0204] A curable composition was prepared using the same process as Example 1, except that only HDDA was used as a monomer and no surface stabilizing additive was used.

[0205]

[0206] [Comparative Example 2]

[0207] A curable composition was prepared using the same process as Example 5, except that only HDDA was used as a monomer and no surface stabilizing additive was used.

[0208]

[0209] [Comparative Example 3]

[0210] A curable composition was prepared using the same process as Example 1, except that only HDDA was used as a monomer and heptaonic acid (HA) was used as a surface stabilizing additive.

[0211] The structure of the HA used is as follows.

[0212]

[0213]

[0214] [Comparative Example 4]

[0215] A curable composition was prepared using the same process as Example 5, except that only HDDA was used as a photopolymerizable monomer and Hexyl amine (HAM) was used as a surface stabilizing additive.

[0216] The structure of the HAM used is as follows.

[0217]

[0218]

[0219] [Experimental Example]

[0220] A photoconversion coating layer was prepared as follows using the photoconversion curable compositions prepared in Examples 1 to 8 and Comparative Examples 1 to 4, and the film thickness, transmittance, color conversion efficiency (PCE), maximum emission wavelength, full width at half maximum (FWHM), and viscosity at this time were measured by the following methods, and the results are shown in Table 2 below.

[0221] The film thickness was measured using a step measurement device (BRUKER DektakXT), and the transmittance, color conversion efficiency (PCE), maximum emission wavelength, and full width at half maximum (FWHM) were measured using a quantum efficiency meter (Otsuka Electronics QE-2100). The viscosity was measured using a Brookfield ametek DV2T viscometer, and the state of the thin film (aggregation, roughness) was observed using an electron microscope. The TiO2 particle size was measured using Otsuka Electronics ELSZ-2000.

[0222] A thin film was produced by spin-coating a curable composition using SPIN3000D from MIDAS SYSTEM Co., Ltd., and the thin film was cured using an exposure device (JooEun Yu V-Tech Co., Ltd., SLC-1000AF-D). The degree of curing (crosslinking) of the thin film was then measured using ALPHA ± (BRUKER Co., Ltd.).

[0223]

[0224] As shown in Table 2 above, the photoconversion curable compositions of Examples 1 to 8 of the present invention are compositions to which a crosslinking-participating ligand additive (surface stabilizing additive) is applied, and compared to Comparative Examples 1 to 4, they exhibited thermal stability of within 5% at 100°C and within 10% at 180°C based on QD-1, and a significantly excellent thermal stability improvement of -0% at 100°C and within 3% at 180°C based on QD-2 was confirmed.

[0225] In addition, when a thin film was manufactured with the composition of Example 6, it was confirmed by FT-IR measurement that the degree of crosslinking of the thin film was improved and a more robust film was formed compared to Comparative Examples 2 and 4, which applied simple additives (HA, HAM) that do not participate in crosslinking (Fig. 1). Specifically, it was confirmed that the degree of crosslinking was improved in the order of Comparative Example 4 < Comparative Example 2 < Example 6.

[0226] This is a result of the stabilization of the quantum dot surface and improvement in membrane planarization and crosslinking degree by forming a polymer by crosslinking the monomer with the crosslinking-participating ligand while binding to the quantum dot surface.

[0227] In particular, it was confirmed that the photoconversion curable compositions of Examples 5 to 8 using QD-2 had an excellent color conversion efficiency (PCE) value of 35% or more and a viscosity of less than 20cp, making them suitable as photoconversion curable compositions included in ink-discharging type color filters and image display devices. In addition, it was confirmed that the emission wavelength was 530 nm to 540 nm and the half-width was 30 nm to 32 nm, showing excellent color purity.

[0228] Ultimately, the present invention reliably achieves low-viscosity, solvent-free, and high-efficiency thin films. Furthermore, thermal process stability is improved, while surface uniformity of the coating is also achieved, significantly enhancing stability. When forming thin films using quantum dots, a desirable result is achieved when there is no difference in efficiency after initial exposure and after heat treatment.

[0229] In particular, when a cross-linking-participating additive is added to a four-component QD, the difference between the efficiency after exposure and the efficiency after heat treatment is smaller, which may be desirable.

[0230] From the above description, those skilled in the art will understand that the present invention can be implemented in other specific forms without altering its technical spirit or essential characteristics. In this regard, it should be understood that the embodiments described above are illustrative in all respects and not restrictive. The scope of the present invention should be interpreted as encompassing all changes or modifications derived from the meaning and scope of the following claims and their equivalent concepts, rather than the detailed description above.

Claims

1. A quantum dot surface-modified with a compound represented by any one of the following chemical formulas 1 to 4; and [Chemical Formula 1] [Chemical formula 2] [Chemical Formula 3] [Chemical Formula 4] A curable composition comprising a photopolymerizable monomer comprising at least one of the compounds represented by the following chemical formulae 5 and 6: [Chemical Formula 5] [Chemical formula 6] In the above chemical formulas 1 to 6, R1 and R2 are the same or different from each other, and each independently represents hydrogen, an acryl group, a cyano group, a nitro group, C1~C 40 Alkyl group of C2~C 40 Alkenyl group of C2~C 40 Alkynyl group, C6~C 40 is selected from the group consisting of an aryl group and a heteroaryl group having 5 to 40 nuclear atoms, The above A is C, O, S or N, The above X is C1~C 40 Alkylene group, C1~C 40 Cycloalkylene group of C1~C 40 Alkyloxylene group, C6~C 40 is an arylene group or a heteroarylene group having 5 to 40 nuclear atoms, The above Y is C1~C 40 Alkyl group or C6~C 40 is an aryl group, The above Z is hydrogen or C, In the above chemical formulas 1 to 4, n is an integer from 1 to 30, In the above chemical formulas 5 and 6, n is an integer from 0 to 12, In the above chemical formula 6, m is an integer from 0 to 2, Acrylic groups of the above X, Y, R1 and R2, C1~C 40 Alkyl group of C2~C 40 Alkenyl group of C2~C 40 Alkynyl group, C6~C 40 Aryl group of , heteroaryl group having 5 to 40 nuclear atoms, C1~C 40 Alkylene group, C1~C 40 Cycloalkylene group of C1~C 40 Alkyloxylene group, C6~C 40 The arylene group and the heteroarylene group having 5 to 40 nuclear atoms are each independently selected from halogen, cyano group, nitro group, C1~C 40 Alkyl group of C2~C 40 Alkenyl group of C2~C 40 Alkynyl group, C3~C 40 Cycloalkyl group of C1~C 40 Alkyloxy group, C6~C 60 Aryloxy group of C6~C 60 It may be substituted with one or more substituents selected from the group consisting of an aryl group and a heteroaryl group having 5 to 40 nuclear atoms, and when there are multiple substituents, they may be the same or different from each other.

2. In paragraph 1, A curable composition, wherein the compound represented by the above chemical formula 5 is selected from the group consisting of A-1 to A-9 below.

3. In paragraph 1, A curable composition, wherein the compound represented by the chemical formula 6 is selected from the group consisting of B-1 to B-8 below.

4. In paragraph 1, A curable composition, wherein the compound represented by any one of the chemical formulas 1 to 4 is contained in an amount of 0.1 to 10 parts by weight based on 100 parts by weight of the total curable composition.

5. In paragraph 1, The above curable composition further comprises a photopolymerization initiator, a light scattering agent or a combination thereof.

6. In paragraph 1, The above curable composition further comprises at least one of a binder resin and a solvent.

7. In paragraph 6, The above binder resin is a curable composition comprising an acrylic binder resin, a cardo binder resin or a combination thereof.

8. In paragraph 6, A curable composition comprising the solvent selected from the group consisting of propylene glycol monomethyl ether acetate, dipropylene glycol methyl ether acetate, cyclohexyl acetate, ethanol, ethylene glycol dimethyl ether, ethylene glycol butyl ether acetate, ethylene diglycol methyl ethyl ether, diethylene glycol dimethyl ether, dimethyl acetamide, dimethyl adipate, cyclohexylacrylate, hydroxyethyl acrylate, 2-butoxyethanol, N-methylpyrrolidine, N-ethylpyrrolidine, propylene carbonate, γ-butyrolactone, acetone or a combination thereof.

9. A cured film comprising the curable composition of paragraph 1.

10. An image display device including a cured film according to Article 9.

Images