TWI851415B - Curable composition, cured layer, color filter and display device - Google Patents

Abstract

Provided are a curable composition, a cured layer manufactured using the curable composition, a color filter including the cured layer, and a display device including the color filter, the curable composition including (A) quantum dots; and (B) a polymerizable compound including a compound represented by Chemical Formula 1. [Chemical Formula 1]

Description

Curable composition, cured layer, color filter and display device

The present disclosure relates to a curable composition, a curable layer made using the composition, a color filter including the curable layer, and a display device including the color filter.

In the case of general quantum dots, the solvent in which the quantum dots are dispersed is limited due to the hydrophobic surface characteristics. Therefore, it is difficult to introduce into polar systems such as adhesives or curable monomers.

For example, even in the case of actively studying quantum dot ink compositions, polarity is relatively low in the initial step and it can be dispersed in a solvent used in a curable composition having high hydrophobicity. Therefore, because the quantum dots are 20 wt% or more based on the total amount of the composition, the light efficiency of the ink cannot be improved to a certain level. Although quantum dots are additionally added and dispersed in order to improve light efficiency, the viscosity is beyond the range that can be jetted and processability may not be satisfied.

In order to achieve a viscosity range capable of ink jetting, a method of reducing the solid content of ink by dissolving a solvent of 50 wt% or more based on the total amount of the composition is also provided, which provides slightly satisfactory results in terms of viscosity. However, although it can be regarded as a satisfactory result in terms of viscosity, nozzle drying, nozzle clogging, and reduction in thickness of a single film over time after ink jetting due to solvent volatilization during ink jetting may become worse, and it is difficult to control thickness deviation after curing. Therefore, it is difficult to apply it to an actual process.

Therefore, solvent-free quantum dot inks that do not contain solvents are the best form for application in actual processes. Current technology for applying quantum dots themselves to solvent-based compositions is now limited to a certain extent.

In the case of solvent-free curable compositions (quantum dot ink compositions), since an excessive amount of polymerizable compounds is contained, blockage and ejection failure due to nozzle drying caused by volatility and a reduction in the thickness of a single layer film due to the volatility of the ink composition ejected in the patterned partition wall pixels may occur. Therefore, efforts have been made from various angles to improve the optical properties of solvent-free curable compositions. In order to improve the optical properties of solvent-free curable compositions, a method of increasing the content of inorganic materials is generally used, but there is a problem that the more inorganic materials there are, the higher the reflectivity. In other words, since there is a trade-off between the improvement of the optical properties of solvent-free curable compositions and the problem of reducing the reflectivity, there is a growing demand for a technology that can simultaneously improve the aforementioned two properties (improvement of optical properties and reduction of reflectivity).

The embodiment provides a curable composition capable of simultaneously improving optical properties and reducing reflectivity.

Another embodiment provides a cured layer made using a curable composition.

Another embodiment provides a color filter including a cured layer.

Another embodiment provides a display device including a color filter.

The embodiment provides a curable composition, the curable composition comprising: (A) quantum dots; and (B) a polymerizable compound, comprising a compound represented by Chemical Formula 1.

In Formula 1, ^L1 is a divalent linking group containing a sulfur atom, but does not contain a disulfide bond (*-SS-*) bonding structure, ^L2 and ^L3 are each independently a single bond, a substituted or unsubstituted C1 to C20 alkylene group, or a substituted or unsubstituted C3 to C20 cycloalkylene group, and ^R1 and ^R2 are each independently a hydrogen atom, a substituted or unsubstituted C1 to C20 alkyl group, a substituted or unsubstituted C3 to C20 cycloalkyl group, or a substituted or unsubstituted C6 to C20 aryl group.

^L1 can be represented by any one of Chemical Formula L-1 to Chemical Formula L-4.

[化學式L-3]

[Chemical formula L-3]

In Formulae L-1 to L-4, ^L4 to ^L8 are each independently a single bond or a substituted or unsubstituted C1 to C20 alkylene group.

The compound represented by Chemical Formula 1 may have a refractive index greater than 1.455.

The compound represented by Chemical Formula 1 may be represented by any one of Chemical Formula 1-1 to Chemical Formula 1-3.

The polymerizable compound may further include a compound having a structure different from that of the compound represented by Chemical Formula 1.

A compound having a structure different from that of the compound represented by Chemical Formula 1 can be represented by Chemical Formula 2.

In Chemical Formula 2, ^L9 is a substituted or unsubstituted C1 to C10 alkylene group, a substituted or unsubstituted C3 to C20 cycloalkylene group, or a keto group (*-O-*), ^L10 and ^L11 are each independently a single bond or a substituted or unsubstituted C1 to C10 alkylene group, and ^R3 and ^R4 are each independently a hydrogen atom, a substituted or unsubstituted C1 to C20 alkyl group, a substituted or unsubstituted C3 to C20 cycloalkyl group, or a substituted or unsubstituted C6 to C20 aryl group.

The compound represented by Chemical Formula 2 may have a refractive index less than or equal to 1.455.

The compound represented by Chemical Formula 1 and a compound having a structure different from that of the compound represented by Chemical Formula 1 may be included in a weight ratio of 1:9 to 9:1.

The curable composition may be a solvent-free curable composition.

Based on the total amount of the solvent-free curable composition, the solvent-free curable composition may contain 5 wt% to 60 wt% of quantum dots and 40 wt% to 95 wt% of polymerizable compounds.

The curable composition may further include a polymerization initiator, a light diffuser, a polymerization inhibitor or a combination thereof.

The light diffuser may include barium sulfate, calcium carbonate, titanium dioxide, zirconium oxide, or a combination thereof.

The curable composition may further comprise a solvent.

The curable composition may include 1 wt % to 40 wt % of quantum dots, 1 wt % to 20 wt % of polymerizable compounds, and 40 wt % to 80 wt % of solvents, based on the total weight of the curable composition.

The curable composition may further include malonic acid, 3-amino 1,2-propylene glycol, a silane coupling agent, a fluorine-based surfactant or a combination thereof.

Another embodiment provides a cured layer made using a curable composition.

The cured layer can have a diffuse reflectivity of 50% to 55%.

Another embodiment provides a color filter including a cured layer.

Another embodiment provides a display device including a color filter.

Other embodiments of the present invention are included in the following embodiments.

The sulfur-containing di(meth)acrylate compound is contained in the curable composition containing quantum dots, and thereby the optical properties of the curable composition containing quantum dots can be improved and the reflectivity can be reduced at the same time.

The embodiments of the present invention are described in detail below. However, these embodiments are illustrative, the present invention is not limited thereto and the present invention is limited by the scope of the patent application.

In this specification, when no specific definition is otherwise provided, "alkyl" refers to C1 to C20 alkyl, "alkenyl" refers to C2 to C20 alkenyl, "cycloalkenyl" refers to C3 to C20 cycloalkenyl, "heterocycloalkenyl" refers to C3 to C20 heterocycloalkenyl, "aryl" refers to C6 to C20 aryl, "aralkyl" refers to C6 to C20 aralkyl, "alkylene" refers to C1 to C20 alkylene, "arylene" refers to C6 to C20 arylene, "alkylarylene" refers to C6 to C20 alkylarylene, "heteroarylene" refers to C3 to C20 heteroarylene, and "alkoxylene" refers to C1 to C20 alkoxylene.

In the present specification, when a specific definition is not otherwise provided, "substituted" refers to the replacement of at least one hydrogen atom by a substituent selected from the following: a halogen atom (F, Cl, Br or I), a hydroxyl group, a C1 to C20 alkoxy group, a nitro group, a cyano group, an amine group, an imino group, an azido group, a formamido group, a hydrazine group, a hydrazone group, a carbonyl group, a carbamoyl group, a thiol group, an ester group, a keto group , carboxyl or its salt, sulfonic acid group or its salt, phosphoric acid or its salt, C1 to C20 alkyl, C2 to C20 alkenyl, C2 to C20 alkynyl, C6 to C20 aryl, C3 to C20 cycloalkyl, C3 to C20 cycloalkenyl, C3 to C20 cycloalkynyl, C2 to C20 heterocycloalkyl, C2 to C20 heterocycloalkenyl, C2 to C20 heterocycloalkynyl, C3 to C20 heteroaryl or a combination thereof.

In this specification, when no specific definition is provided, "hetero" refers to a hetero atom containing at least one N, O, S and P in the chemical formula.

In this specification, when no specific definition is otherwise provided, "(meth)acrylate" refers to both "acrylate" and "methacrylate", and "(meth)acrylic acid" refers to both "acrylic acid" and "methacrylic acid".

In this specification, when no specific definition is otherwise provided, the term "combination" refers to mixing or copolymerization.

In this specification, when no definition is otherwise provided, when a chemical bond is not drawn at a position where it should be given in a chemical formula, a hydrogen bond is formed at the position.

In addition, in this specification, when no additional definition is provided, "*" refers to the connection point with the same or different atoms or chemical formulas.

Hereinafter, each component constituting the curable composition according to the embodiment is described in detail.

Polymerizable compounds

The quantum dot-containing curable composition according to the embodiment contains a sulfur-containing di(meth)acrylate compound having a high refractive index as a polymerizable compound, so that the high refractive property of the sulfur-containing di(meth)acrylate compound can cause the improvement of the optical properties of the curable composition, and further, when the curable composition is thermally cured, a thiol-ene addition reaction is induced to promote the surface curing of the cured layer of the curable composition, thereby simultaneously satisfying the reflectivity reduction effect.

The sulfur-containing di(meth)acrylate compound can be represented by Chemical Formula 1.

In Formula 1, ^L1 is a divalent linking group containing a sulfur atom, but does not contain a disulfide bond (*-SS-*) bonding structure, ^L2 and ^L3 are each independently a single bond, a substituted or unsubstituted C1 to C20 alkylene group, or a substituted or unsubstituted C3 to C20 cycloalkylene group, and ^R1 and ^R2 are each independently a hydrogen atom, a substituted or unsubstituted C1 to C20 alkyl group, a substituted or unsubstituted C3 to C20 cycloalkyl group, or a substituted or unsubstituted C6 to C20 aryl group.

Curable compositions containing green quantum dots have relatively low absorptivity (absolute value) and light efficiency (EQE), and reflectivity that is approximately twice as high as that of curable compositions containing red quantum dots. Therefore, there are unresolved technical challenges to improving the brightness of green quantum dot pixels in panels, but reducing the reflection of external light requires further improvements in the brightness of the front side.

The inventors have clearly recognized the above problems and have conducted relevant research for a long time to improve the optical properties of the curable composition containing green quantum dots while reducing its reflectivity. After hundreds of trials and errors, they finally successfully solved the technical challenges by applying the compound represented by Chemical Formula 1 as a polymerizable compound.

Generally speaking, in order to improve the optical properties of a curable composition containing green quantum dots, the method of increasing the content of inorganic materials is mainly used, but in contrast, in order to reduce the reflectivity of a curable composition containing green quantum dots, the method of reducing the content of inorganic materials is used, wherein the improvement of optical properties and the reduction of reflectivity are relative to each other, that is, there is a trade-off relationship, which can make it difficult to achieve both properties at the same time.

According to the embodiment, a sulfur-containing di(meth)acrylate compound represented by Chemical Formula 1 as a polymerizable compound is applied to a curable composition, thereby achieving optical property improvement and reflection reduction effects in a curable composition containing green quantum dots in addition to a curable composition containing red quantum dots.

Specifically, due to the high refractive index of the compound represented by Chemical Formula 1, optical properties can be improved. For example, the compound represented by Chemical Formula 1 may have a refractive index greater than 1.455, for example, greater than 1.455 and less than or equal to 1.7, wherein Since the compound represented by Chemical Formula 1 has a high refractive index within the range, the optical properties of the curable composition containing the compound as a content quantum dot of the polymerizable compound can be greatly improved.

In addition, since the compound represented by Chemical Formula 1 used as a polymerizable compound is thermally decomposed during the thermal curing of the curable composition of the embodiment to expose a thiol group, and this thiol group is easy to induce a thiol-ene reaction with the carbon-carbon double bond of the (meth)acrylate group (refer to the following reaction scheme), and thus promotes the surface curing of the thermally cured single film, ultimately significantly reducing the reflectivity of the cured layer, especially the diffuse reflectivity, so that the reflectivity reduction can be obtained. For example, the diffuse reflectivity of the cured layer can be reduced to less than or equal to 55%, such as 50% to 55%.

In Chemical Formula 1, when ^L1 includes a disulfide bond (*-SS-*) linking structure, or ^L2 or ^L3 includes an aryl group as a linking group, the compound may have a lower refractive index and disadvantages in optical properties, and in addition, the thiol-ene reaction does not occur smoothly, thereby reducing the reflectivity reducing effect to half.

For example, ^L1 can be represented by any one of Chemical Formula L-1 to Chemical Formula L-4.

[Chemical formula L-2]

In Formulae L-1 to L-4, ^L4 to ^L8 are each independently a single bond or a substituted or unsubstituted C1 to C20 alkylene group.

When the ^L1 linking group of Chemical Formula 1 has the above structure, it may be extremely advantageous to simultaneously achieve the effects of improving the optical properties of the curable composition according to the embodiment and reducing its reflectivity (diffuse reflectivity).

For example, the compound represented by Chemical Formula 1 can be represented by any one of Chemical Formula 1-1 to Chemical Formula 1-3, but is not necessarily limited thereto.

For example, the polymerizable compound may further include a compound having a structure different from that of the compound represented by Chemical Formula 1. That is, the polymerizable compound may include the compound represented by Chemical Formula 1 and another compound having a different structure.

For example, a compound having a structure different from that of the compound represented by Chemical Formula 1 can be represented by Chemical Formula 2.

In Chemical Formula 2, ^L9 is a substituted or unsubstituted C1 to C10 alkylene group, a substituted or unsubstituted C3 to C20 cycloalkylene group, or a keto group (*-O-*), ^L10 and ^L11 are each independently a single bond or a substituted or unsubstituted C1 to C10 alkylene group, and ^R3 and ^R4 are each independently a hydrogen atom, a substituted or unsubstituted C1 to C20 alkyl group, a substituted or unsubstituted C3 to C20 cycloalkyl group, or a substituted or unsubstituted C6 to C20 aryl group.

Even if the curable composition according to the embodiment further comprises the compound represented by Chemical Formula 2 and the compound represented by Chemical Formula 1 having a high refractive index as polymerizable compounds, the effects of improving the optical properties of the curable composition and reducing the reflectivity can be achieved at the same time, as in the case of using the compound represented by Chemical Formula 1 alone.

For example, the compound represented by Chemical Formula 2 may have a refractive index less than or equal to 1.455. When the compound represented by Chemical Formula 2 has a refractive index greater than 1.455, it is advantageous in improving optical properties, but may be disadvantageous in terms of reducing reflectivity.

For example, the compound represented by Chemical Formula 1 and a compound having a structure different from that of the compound represented by Chemical Formula 1 (e.g., a compound represented by Chemical Formula 2, etc.) have a weight ratio of 1:9 to 9:1, such as a weight ratio of 5:5 to 9:1.

For example, the compound represented by Chemical Formula 1 may be contained in a higher amount than a compound having a structure different from that of the compound represented by Chemical Formula 1 (e.g., a compound represented by Chemical Formula 2, etc.).

For example, the compound represented by Chemical Formula 1 and a compound having a structure different from that of the compound represented by Chemical Formula 1 (for example, a compound represented by Chemical Formula 2, etc.) may be included in a weight ratio of 6:4 to 9:1.

When the compound represented by Chemical Formula 1 is contained in a higher amount than a compound having a structure different from that of the compound represented by Chemical Formula 1 (e.g., a compound represented by Chemical Formula 2, etc.), for example, at a weight ratio of 6:4 to 9:1, the curing rate of the curable composition according to the embodiment increases, and the simultaneous improvement of the two effects of improving optical characteristics and reducing reflectivity can be maximized.

For example, the compound represented by Chemical Formula 2 can be represented by Chemical Formula 2-1 or Chemical Formula 2-2, but is not necessarily limited thereto.

[Chemical formula 2-1]

For example, in addition to the compounds represented by Chemical Formula 2-1 and Chemical Formula 2-2, the compound having a structure different from that of the compound represented by Chemical Formula 1 may further include: 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, trihydroxymethylpropane triacrylate, novolac epoxy acrylate, ethylene glycol dimethacrylate, triethylene glycol dimethacrylate, propylene glycol dimethacrylate, 1,4-butanediol dimethacrylate, 1,6-hexanediol dimethacrylate, or a combination thereof.

In addition to the polymerizable compound, a monomer commonly used in a known thermosetting or photocurable composition may be further used, and for example, the monomer may further include an oxacyclobutane compound such as bis[1-ethyl(3-oxacyclobutane)]methanone.

The polymerizable compound may be included in an amount of 40 wt % to 95 wt %, for example, 50 wt % to 90 wt %, based on the total amount of the solvent-free curable composition. When the polymerizable compound is included in the range, a solvent-free curable composition having a viscosity capable of inkjetting may be prepared, and the quantum dots in the prepared solvent-free curable composition may have improved dispersibility, thereby improving optical properties.

For example, the polymerizable compound may have a molecular weight of 170 g/mol to 1,000 g/mol. When the polymerizable compound has a molecular weight within the range, it may be advantageous for inkjetting because it does not increase the viscosity of the composition without interfering with the optical properties of the quantum dots.

In addition, when the curable composition includes a solvent, the polymerizable compound may be included in an amount of 1 wt % to 20 wt %, 1 wt % to 15 wt %, for example, 5 wt % to 15 wt %, based on the total amount of the curable composition. When the polymerizable compound is included in the above range, the optical properties of the quantum dots may be improved.

Quantum dots

For example, quantum dots can have a maximum fluorescence emission wavelength between 500 nm and 680 nm.

For example, when the curable composition according to the embodiment is a solvent-free curable composition, the quantum dots may be included in an amount of 5 wt % to 60 wt %, such as 10 wt % to 60 wt %, such as 20 wt % to 60 wt %, such as 30 wt % to 50 wt %. When the quantum dots are included in the above range, high light retention and light efficiency can be achieved even after curing.

For example, when the curable composition according to the embodiment is a curable composition containing a solvent, the quantum dots may be included in an amount of 1 wt% to 40 wt%, for example, 3 wt% to 30 wt%, based on the total amount of the curable composition. When the quantum dots are included in the above range, the light conversion efficiency is improved without weakening the pattern characteristics and the development characteristics, so that excellent processability can be obtained.

For example, the quantum dot absorbs light in the wavelength region of 360 nm to 780 nm, such as 400 nm to 780 nm, and emits fluorescence in the wavelength region of 500 nm to 700 nm, such as 500 nm to 580 nm, or emits fluorescence in the wavelength region of 600 nm to 680 nm. That is, the quantum dot may have a maximum fluorescence emission wavelength (λ _em ) at 500 nm to 680 nm.

The 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) in the range, the color reproducibility is increased when used as a color material in a color filter due to high color purity.

Quantum dots can be independently organic materials or inorganic materials, or a mixture of organic and inorganic materials.

The quantum dots may each independently consist of a core and a shell surrounding the core, and the core and the shell may each independently have a core, core/shell, core/first shell/second shell, alloy, alloy/shell or similar structure consisting of Group II to Group IV, Group III to Group V and the like, but are not limited thereto.

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

In the embodiment, since the concern for the environment has greatly increased worldwide recently and the restrictions on toxic materials have also been strengthened, non-cadmium-based luminescent materials (InP/ZnS, InP/ZeSe/ZnS, etc.) with slightly lower quantum efficiency (quantum yield) but environmentally friendly are used instead of luminescent materials with cadmium-based cores, but not necessarily limited thereto.

In the case of core/shell structured quantum dots, the overall size (average particle size) including the shell may be 1 nm to 15 nm, for example 5 nm to 15 nm.

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

On the other hand, for the dispersion stability of quantum dots, the curable composition according to the embodiment may further include a dispersant. The dispersant contributes to the uniform dispersion of the photoconversion material such as the quantum dots in the curable composition, and may include a non-ionic, anionic or cationic dispersant. Specifically, the dispersant may be polyalkylene glycol or its ester, polyoxyalkylene glycol, polyol ester epoxide addition product, ethanol epoxide addition product, sulfonate, sulfonate salt, carboxylate, carboxylate salt, alkylamide epoxide addition product, alkylamine and the like, and it may be used alone or in the form of a mixture 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 light conversion material such as quantum dots.

For example, the quantum dots may be quantum dots that have been surface-modified with a ligand having a polar group, such as a ligand having a high affinity for the polymerizable compound. In the case of surface-modified quantum dots as described above, it is very easy to prepare a high concentration or highly concentrated dispersion of quantum dots (improving the dispersibility of the quantum dots relative to the polymerizable compound), which can have a huge impact on improving light efficiency and in particular can be advantageous for implementing solvent-free curable compositions.

For example, a ligand having a polar group may have a structure that has a high affinity for the chemical structure of the polymerizable compound.

For example, a ligand having a polar group can be represented by any one of Chemical Formula A to Chemical Formula Q, but is not necessarily limited thereto.

[Chemical formula A]

In the chemical formula D, m1 is an integer from 0 to 10.

[Chemical formula H]

When a ligand is used, the surface modification of quantum dots can become easier, and when the quantum dots surface-modified with the ligand are added to the aforementioned polymerizable compound and then stirred, an extremely transparent dispersion can be obtained, which confirms that the surface modification of the quantum dots is extremely sufficiently performed.

Light diffuser

The curable composition according to the embodiment may further include a light diffuser.

For example, the light diffuser may include barium sulfate (BaSO ₄ ), calcium carbonate (CaCO ₃ ), titanium dioxide (TiO ₂ ), zirconium oxide (ZrO ₂ ), or a combination thereof.

The light diffuser can reflect the light that is not absorbed by the quantum dots and allow the quantum dots to absorb the reflected light again. That is, the light diffuser can increase the amount of light absorbed by the quantum dots and improve the light conversion efficiency of the curable composition.

The light diffuser may have an average particle size (D ₅₀ ) of 150 nm to 250 nm, and specifically 180 nm to 230 nm. When the average particle size of the light diffuser is within the range, it may have a better light diffusion effect and improve light conversion efficiency.

The light diffuser may be included in an amount of 1 wt% to 20 wt%, such as 2 wt% to 15 wt%, such as 3 wt% to 10 wt%, based on the total amount of the curable composition. When less than 1 wt% of the light diffuser is included in the total amount of the curable composition, it is difficult to expect the effect of improving the light conversion efficiency by using the light diffuser, and when more than 20 wt% of the light diffuser is included, quantum dot precipitation problems may occur.

Polymerization initiator

The curable composition according to the embodiment may further include a polymerization initiator, such as a photopolymerization initiator, a thermal polymerization initiator or a combination thereof.

The photopolymerization initiator may be a commonly used initiator for photosensitive resin compositions, such as acetophenone compounds, benzophenone compounds, thiophenone compounds, benzoin compounds, triazine compounds, oxime compounds, aminoketone compounds and the like, but is not necessarily limited thereto.

Examples of acetophenone compounds include 2,2'-diethoxyacetophenone, 2,2'-dibutoxyacetophenone, 2-hydroxy-2-methylpropiophenone, tert-butyltrichloroacetophenone, tert-butyldichloroacetophenone, 4-chloroacetophenone, 2,2'-dichloro-4-phenoxyacetophenone, 2-methyl-1-(4-(methylthio)phenyl)-2-morpholinopropan-1-one, 2-benzyl-2-dimethylamino-1-(4-morpholinophenyl)butan-1-one, and the like.

Examples of benzophenone compounds include benzophenone, benzyl benzoate, methyl benzoylbenzoate, 4-phenylbenzophenone, hydroxybenzophenone, acrylated benzophenone, 4,4'-bis(dimethylamino)benzophenone, 4,4'-bis(diethylamino)benzophenone, 4,4'-dimethylaminobenzophenone, 4,4'-dichlorobenzophenone, 3,3'-dimethyl-2-methoxybenzophenone, and the like.

Examples of thiothione compounds include thiothione, 2-methylthiothione, isopropylthiothione, 2,4-diethylthiothione, 2,4-diisopropylthiothione, 2-chlorothiothione and the like.

Examples of benzoin compounds include benzoin, benzoin methyl ether, benzoin ethyl ether, benzoin isopropyl ether, benzoin isobutyl ether, benzyl dimethyl ketal and the like.

Examples of triazine compounds include 2,4,6-trichloro-s-triazine, 2-phenyl-4,6-bis(trichloromethyl)-s-triazine, 2-(3',4'-dimethoxyphenyl)-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, s-triazine, 2-biphenyl-4,6-bis(trichloromethyl)-s-triazine, bis(trichloromethyl)-6-phenylvinyl-s-triazine, 2-(naphthol-yl)-4,6-bis(trichloromethyl)-s-triazine, 2-(4-methoxynaphthol-yl)-4,6-bis(trichloromethyl)-s-triazine, 2-4-bis(trichloromethyl)-6-piperonyl-s-triazine, 2-4-bis(trichloromethyl)-6-(4-methoxyphenylvinyl)-s-triazine and the like.

Examples of oxime compounds include O-acyl oxime 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, and the like. Specific examples of O-acyl oxime compounds may be 1,2-octanedione, 2-dimethylamino-2-(4-methylbenzyl)-1-(4-pyrrol-4-yl-phenyl)-butan-1-one, 1-(4-phenylthiophenyl)-butane-1,2-dione-2-oxime-O-benzoate, 1-(4-phenylthiophenyl)-octane-1,2-dione-2-oxime-O-benzoate, 1-(4-phenylthiophenyl)-octane-1,2-dione-2-oxime-O-benzoate, 1-(4-phenylthiophenyl)-octan-1-one oxime-O-acetate, 1-(4-phenylthiophenyl)-butan-1-one oxime-O-acetate and the like.

Examples of aminoketone compounds include 2-benzyl-2-dimethylamino-1-(4-morpholinophenyl)butanone-1 and the like.

In addition to the above compounds, the photopolymerization initiator may further include carbazole compounds, diketone compounds, cobalt borate compounds, diazo compounds, imidazole compounds, biimidazole compounds and the like.

The photopolymerization initiator can be used together with a photosensitizer that can cause a chemical reaction by absorbing light and becoming excited and then transferring its energy.

Examples of photosensitizers may include tetraethylene glycol di-3-butyl propionate, pentaerythritol tetra-3-butyl propionate, dipentaerythritol tetra-3-butyl propionate, and the like.

Examples of thermal polymerization initiators may be peroxides, specifically, benzoyl peroxide, dibenzoyl peroxide, lauryl peroxide, dilauryl peroxide, di-tert-butyl peroxide, cyclohexane peroxide, methyl ethyl ketone peroxide, hydrogen peroxide (e.g., tert-butyl hydrogen peroxide, isopropylbenzene hydrogen peroxide), dicyclohexyl peroxydicarbonate, 2,2-azo-bis(isobutyronitrile), tert-butyl perbenzoate, and the like, such as 2,2'-azobis-2-methylpropionitrile, but are not necessarily limited thereto, and any peroxide known in the art may be used.

The polymerization initiator may be included in an amount of 0.1 wt% to 5 wt%, for example, 1 wt% to 4 wt%, based on the total amount of the curable composition. When the polymerization initiator is included in the range, it is possible to obtain excellent reliability due to sufficient curing during exposure or heat curing, and it is possible to prevent the transmittance from being degraded due to the non-reactive initiator, thereby preventing the optical properties of the quantum dots from being degraded.

Adhesive resin

The curable composition according to the embodiment may further include a binder resin.

The adhesive resin may include an acrylic resin, a cardo resin, an epoxy resin or a combination thereof.

The acrylic resin may be a copolymer of a first olefinic unsaturated monomer and a second olefinic unsaturated monomer copolymerizable therewith, and may be a resin containing at least one acrylic repeating unit.

Specific examples of acrylic adhesive resins may be polybenzyl methacrylate, (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, and the like, but are not limited thereto, and may be used alone or in the form of a mixture of two or more.

The weight average molecular weight of the acrylic adhesive resin may be 5,000 g/mol to 15,000 g/mol. When the acrylic adhesive resin has a weight average molecular weight within the range, the close contact property with the substrate, the physical property and the chemical property are improved, and the viscosity is appropriate.

The acid value of the acrylic resin may be 80 mg potassium hydroxide/g to 130 mg potassium hydroxide/g. When the acrylic resin has an acid value within the range, an excellent resolution of pixels may be obtained.

Cardoline resins can be used in known curable resin (or photosensitive resin) compositions, and can be used, for example, as disclosed in Korean Patent Publication No. 10-2018-0067243, but are not limited thereto.

The cardo-based resin can be prepared, for example, by mixing at least two of the following compounds: a fluorene-containing compound such as 9,9-bis(4-oxiranylmethoxyphenyl)fluorene; an anhydride compound such as benzenetetracarboxylic dianhydride, naphthalenetetracarboxylic dianhydride, biphenyltetracarboxylic dianhydride, benzophenonetetracarboxylic dianhydride, pyromellitic dianhydride, cyclobutanetetracarboxylic dianhydride, perylenetetracarboxylic dianhydride, tetrahydrofurantetracarboxylic dianhydride, and tetrahydrophthalic anhydride; Alcohol compounds, such as ethylene glycol, propylene glycol and polyethylene glycol; alcohol compounds, such as methanol, ethanol, propanol, n-butanol, cyclohexanol and benzyl alcohol; solvent compounds, such as propylene glycol methyl ethyl acetate and N-methylpyrrolidone; phosphorus-containing compounds, such as triphenylphosphine; and amine or ammonium salt compounds, such as tetramethylammonium chloride, tetraethylammonium bromide, benzyldiethylamine, triethylamine, tributylamine or benzyltriethylammonium chloride.

The weight average molecular weight of the cardo-based binder resin may be 500 g/mol to 50,000 g/mol, for example, 1,000 g/mol to 30,000 g/mol. When the weight average molecular weight of the cardo-based binder resin is within the range, a satisfactory pattern may be formed without residue during the production of the cured layer and without loss of film thickness during the development of the curable composition.

When the binder resin is a cardo resin, the developing property of the curable composition containing the binder resin, in particular the photosensitive resin composition, is improved, and the sensitivity during photocuring is good, so as to improve the fine pattern forming property.

Epoxy resins may be thermally polymerizable monomers or oligomers and may include compounds having carbon-carbon unsaturated bonds and carbon-carbon ring bonds.

Epoxy resins may include, but are not limited to, bisphenol A epoxy resins, bisphenol F epoxy resins, phenol novolac epoxy resins, cycloaliphatic epoxy resins, and aliphatic polyglycidyl ethers, but are not necessarily limited thereto.

Since the commercially available products of the compound may be: diphenyl epoxy resins, such as YX4000, YX4000H, YL6121H, YL6640 or YL6677 of Yuka Shell Epoxy Co.; cresol novolac epoxy resins, such as EOCN-102, EOCN-103S, EOCN-104S, EOCN-1020, EOCN-1025 and EOCN-1027 of Nippon Kayaku Co., Ltd., and EPIKOTE 180S75 and similar; bisphenol A epoxies such as EPIKOTE 1001, EPIKOTE 1002, EPIKOTE 1003, EPIKOTE 1004, EPIKOTE 1007, EPIKOTE 1009, EPIKOTE 1010 and EPIKOTE 828 from Eukashell Epoxy Co., Ltd.; bisphenol F epoxies such as EPIKOTE 807 and EPIKOTE 834 from Eukashell Epoxy Co., Ltd.; phenol novolac epoxies such as EPIKOTE 152, EPIKOTE 154 and EPIKOTE 157H65, and EPPN 201 and EPPN 202 of Nippon Kayaku Co., Ltd., and EPPN 201 and EPPN 202 of Nippon Kayaku Co., Ltd.; cycloaliphatic epoxy resins, such as CY175, CY177 and CY179 of CIBA-GEIGY AG, ERL-4234, ERL-4299, ERL-4221 and ERL-4206 of Union Carbide Corporation (U.C.C), Shodyne 509 of Showa Denko K.K., Araldite CY-182 of Ciba-Geigy, Dainippon Ink & Chemicals Co., Ltd. CY-192 and CY-184 of EPICLON Chemicals, Inc., EPICLON 200 and EPICLON 400, EPIKOTE 871, EPIKOTE 872 of Eukashell Epoxy Resin Co., Ltd., and EP1032H60, ED-5661 and ED-5662 of Celanese Coatings Corporation, so the aliphatic polyglycidyl ether can be EPIKOTE 190P and EPIKOTE 191P of Eukashell Epoxy Resin Co., Ltd., Epolite 100MF of Kyoesha Yushi Co., Ltd., Epiol TMP of Nippon Yushi Co., Ltd., and the like.

For example, when the curable composition according to the embodiment is a solvent-free curable composition, the binder resin may be included in an amount of 0.5 wt % to 10 wt %, for example, 1 wt % to 5 wt %, based on the total amount of the curable composition. In this case, the heat resistance and chemical resistance of the solvent-free curable composition may be improved, and the storage stability of the composition may also be improved.

For example, when the curable composition according to the embodiment is a curable composition containing a solvent, the binder resin may be contained in an amount of 1 wt % to 30 wt %, for example, 3 wt % to 20 wt %, based on the total amount of the curable composition. In this case, pattern characteristics, heat resistance, and chemical resistance may be improved.

Other additives

In order to improve the stability and dispersion of quantum dots, the curable composition according to the embodiment may further include a polymerization inhibitor.

The polymerization inhibitor may include a hydroquinone compound, a catechol compound, or a combination thereof, but is not necessarily limited thereto. When the curable composition according to the embodiment further includes a hydroquinone compound, a catechol compound, or a combination thereof, room temperature crosslinking during exposure after coating the curable composition can be prevented.

For example, the hydroquinone compound, catechol compound or a combination thereof may be hydroquinone, methyl hydroquinone, methoxy hydroquinone, tert-butyl hydroquinone, 2,5-di-tert-butyl hydroquinone, 2,5-bis(1,1-dimethylbutyl) hydroquinone, 2,5-bis(1,1,3,3-tetramethylbutyl) hydroquinone, catechol, tert-butyl catechol, 4-methoxyphenol, benzyltriol, 2,6-di-tert-butyl-4-methylphenol, 2-naphthol, tris(N-hydroxy-N-nitrosoanilino-O,O')aluminum or a combination thereof, but is not necessarily limited thereto.

The hydroquinone compound, the catechol compound or a combination thereof can be used in the form of a dispersion. The polymerization inhibitor in the form of a dispersion can be included in an amount of 0.001 wt % to 3 wt %, for example, 0.01 wt % to 2 wt %, based on the total amount of the curable composition. When the polymerization inhibitor is included in the range, the passage of time at room temperature can be solved, and at the same time, the reduction in sensitivity and the surface stratification phenomenon can be prevented.

In addition, the curable composition according to the embodiment may further include malonic acid, 3-amino-1,2-propylene glycol, a silane coupling agent, a leveling agent, a fluorine-based surfactant or a combination thereof to improve heat resistance and reliability.

For example, the curable composition according to the embodiment may further include a silane coupling agent having a reactive substituent such as a vinyl group, a carboxyl group, a methacryloyl group, an isocyanate group, an epoxy group, and the like, so as to improve the close contact property with the substrate.

Examples of silane coupling agents include trimethoxysilylbenzoic acid, γ-methacryloylpropoxytrimethoxysilane, vinyltriacetoxysilane, vinyltrimethoxysilane, γ-isocyanatepropyltriethoxysilane, γ-glycidyloxypropyltrimethoxysilane, β-((cyclohexyl)-epoxy)ethyltrimethoxysilane, and the like, and these silane coupling agents may be used alone or in the form of a mixture of two or more.

The silane coupling agent may be used in an amount of 0.01 to 10 parts by weight based on 100 parts by weight of the curable composition. When the silane coupling agent is included within the range, close contact properties, storage capacity, and the like are improved.

In addition, the curable composition may further contain a surfactant, such as a fluorine-based surfactant, as needed, in order to improve the coating properties and inhibit the generation of spots, that is, to improve the leveling performance.

The fluorine-based surfactant may have a low weight average molecular weight of 4,000 g/mol to 10,000 g/mol, and specifically 6,000 g/mol to 10,000 g/mol. In addition, the fluorine-based surfactant may have a surface tension of 18 mN/m to 23 mN/m (measured as a 0.1% polyethylene glycol monomethylether acetate (PGMEA) solution). When the fluorine-based surfactant has a weight average molecular weight and surface tension within the range, the leveling performance can be further improved, and when applied to narrow gap coating for high-speed coating, excellent properties can be provided, because less film defects can be generated by preventing spot generation and suppressing vapor generation during high-speed coating.

Examples of fluorine-based surfactants include BM- ^1000® and BM- ^1100® (BM Chemie Inc.); MEGAFACE F ^142D® , MEGAFACE F ^172® , MEGAFACE F ^173® , and MEGAFACE F ^183® (Dainippon Ink Kagaku Kogyo Co., Ltd.); FULORAD FC- ^135® , FULORAD FC- ^170C® , FULORAD FC- ^430® , and FULORAD FC- ^431® (Sumitomo 3M Co., Ltd.); SURFLON S- ^112® , SURFLON S-113®, and SURFLON S-135®. ^® , Solon S-131 ^® , Solon S-141 ^® and Solon S-145 ^® (ASAHI Glass Co., Ltd.); and SH-28PA ^® , SH-190 ^® , SH-193 ^® , SZ-6032 ^® and SF-8428 ^® and the like (Toray Silicone Co., Ltd.); F-482, F-484, F-478, F-554 and the like from Dainippon Ink and Chemicals Co., Ltd. (DIC Co., Ltd.).

In addition, in addition to the fluorine-based surfactant, the curable composition according to the embodiment may also include a silicone-based surfactant. Specific examples of silicone-based surfactants may be TSF400, TSF401, TSF410, TSF4440 and the like from Toshiba Silicone Co., Ltd., but are not limited thereto.

The 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 curable composition. When the surfactant is included within the range, fewer foreign substances are generated in the spray composition.

In addition, unless the properties are deteriorated, the curable composition according to the embodiment may further contain a predetermined amount of other additives, such as antioxidants, stabilizers, and the like.

Solvent

Meanwhile, the curable composition according to the embodiment may further contain a solvent.

The solvent may, for example, include alcohols such as methanol, ethanol, and the like; glycol ethers such as ethylene glycol methyl ether, ethylene glycol ethyl ether, propylene glycol methyl ether, and the like; 2-ethoxyethyl acetate (cellosolve acetate) such as 2-methyl acetate (methyl cellosolve acetate), 2-ethoxyethyl acetate (ethyl cellosolve acetate), 2-ethoxydiethyl acetate (diethyl cellosolve acetate), and the like. acetate) and the like; carbitols such as methyl ethyl carbitol, diethyl carbitol, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol dimethyl ether, diethylene glycol methyl ethyl ether, diethylene glycol diethyl ether and the like; propylene glycol alkyl ether acetates such as propylene glycol monomethyl ether acetate, propylene glycol propyl ether acetate and the like; ketones such as methyl ethyl ketone, cyclohexanone, 4-hydroxy-4-methyl-2-pentanone, methyl n-propyl ketone, methyl n-butyl ketone, methyl n-amyl ketone, 2-heptanone and the like; saturated aliphatic monocarboxylic acid alkyl esters such as ethyl acetate, n-butyl acetate, isobutyl acetate and the like ; lactic acid esters such as methyl lactate, ethyl lactate and the like; alkyl hydroxyacetates such as methyl hydroxyacetate, ethyl hydroxyacetate, butyl hydroxyacetate and the like; alkoxyalkyl acetates such as methoxymethyl acetate, methoxyethyl acetate, methoxybutyl acetate, ethoxymethyl acetate, ethoxyethyl acetate and the like; alkyl 3-hydroxypropionates such as methyl 3-hydroxypropionate, ethyl 3-hydroxypropionate and the like; alkyl 3-alkoxypropionates such as methyl 3-methoxypropionate, ethyl 3-methoxypropionate, ethyl 3-ethoxypropionate, methyl 3-ethoxypropionate and the like; alkyl 2-hydroxypropionates such as methyl such as methyl 2-hydroxypropionate, ethyl 2-hydroxypropionate, propyl 2-hydroxypropionate and the like; alkyl 2-alkoxypropionates such as methyl 2-methoxypropionate, ethyl 2-methoxypropionate, ethyl 2-ethoxypropionate, methyl 2-ethoxypropionate and the like; alkyl 2-hydroxy-2-methylpropionates such as methyl 2-hydroxy-2-methylpropionate, ethyl 2-hydroxy-2-methylpropionate and the like; alkyl 2-alkoxy-2-methylpropionates such as methyl 2-methoxy-2-methylpropionate, ethyl 2-ethoxy-2-methylpropionate and the like; esters such as 2-hydroxyethyl propionate, 2-hydroxy-2-methylethyl propionate; Esters, hydroxyethyl acetate, methyl 2-hydroxy-3-methylbutyrate and the like; or ketoesters such as ethyl pyruvate and the like, and in addition, may be N-methylformamide, N,N-dimethylformamide, N-methylformaniline, N-methylacetamide, N,N-dimethylacetamide, N-methylpyrrolidone, dimethylsulfoxide, benzyl ethyl ether, dihexyl ether, acetylacetone, isophorone, hexanoic acid, octanoic acid, 1-octanol, 1-nonanol, benzyl alcohol, benzyl acetate, ethyl benzoate, diethyl oxalate, diethyl maleate, γ-butyrolactone, ethylene carbonate, propylene carbonate, 2-phenoxyethyl acetate and the like, but are not limited thereto.

For example, the solvent may desirably be glycol ethers such as ethylene glycol monoethyl ether, ethylene diglycol methyl ethyl ether, and the like; ethylene glycol alkyl ether acetates such as 2-ethoxyethyl acetate and the like; esters such as 2-hydroxyethyl propionate and the like; carbitols such as diethylene glycol monomethyl ether and the like; propylene glycol alkyl ether acetates such as propylene glycol monomethyl ether acetate, propylene glycol propyl ether acetate, and the like; alcohols such as ethanol and the like, or combinations thereof.

For example, the solvent may be a polar solvent including propylene glycol monomethyl ether acetate, dipropylene glycol methyl ether acetate, ethanol, ethylene glycol dimethyl ether, ethylene diglycol methyl ethyl ether, diethylene glycol dimethyl ether, 2-butoxyethanol, N-methylpyrrolidine, N-ethylpyrrolidine, propylene carbonate, γ-butyrolactone or a combination thereof.

The solvent may be included in an amount of 40 wt % to 80 wt %, for example, 45 wt % to 80 wt %, based on the total amount of the curable composition. When the solvent is within the range, the solvent-type curable composition has an appropriate viscosity and thus can have excellent coating properties when coating a large area by spin coating and slit coating.

Another embodiment provides a cured layer made using a curable composition, a color filter including the cured layer, and a display device including the color filter. In this case, the cured layer may have a diffuse reflectivity of 50% to 55% as described above.

One method of manufacturing a cured layer may include applying the aforementioned curable composition and the solvent-based curable composition on a substrate using an inkjet coating method to form a pattern (S1) and curing the pattern (S2).

(S1) Forming a pattern

The curable composition can be applied to the substrate to a thickness of about 0.5 micrometers to about 20 micrometers using an inkjet coating method. The inkjet coating method can form a pattern by spraying a single color according to each nozzle and thus repeating the spraying multiple times according to the required number of colors, but can form a pattern by spraying the required number of colors simultaneously through each inkjet nozzle to reduce the process.

(S2) Solidification

The obtained pattern is cured to obtain pixels. In this article, the curing method may be a thermal curing process or a photocuring process. The thermal curing process may be performed at a temperature greater than or equal to about 100°C, desirably in the range of about 100°C to about 300°C, and more desirably in the range of about 160°C to about 250°C. The photocuring process may include irradiating actinic rays, such as UV rays of 190 nm to 450 nm, for example, 200 nm to 500 nm. Irradiation is performed by using a light source such as a mercury lamp, a metal halide lamp, an argon laser, and the like having low pressure, high pressure, or ultra-high pressure. X-rays, electron beams, and the like may also be used as needed.

Another method of manufacturing a cured layer may include manufacturing a cured layer using the aforementioned curable composition by the following lithography method.

(1) Coating and film formation

The curable resin composition is applied to a substrate subjected to a predetermined pretreatment to have a desired thickness, for example, a thickness in the range of about 2 micrometers to about 10 micrometers, using a spin coating or slit coating method, a roll coating method, a screen printing method, a coating method, and the like. Then, the coated substrate is heated at a temperature of about 70° C. to about 90° C. for about 1 minute to about 10 minutes to remove the solvent and form a film.

(2) Exposure

After placing a mask having a predetermined shape, the resulting film is irradiated with actinic radiation such as UV radiation of 190 nm to 450 nm, for example, 200 nm to 400 nm, to form a desired pattern. Irradiation is performed by using a light source such as a mercury lamp, a metal halide lamp, an argon laser, and the like having low pressure, high pressure, or ultra-high pressure. X-rays, electron beams, and the like may also be used as needed.

When a high-pressure mercury lamp is used, the exposure process uses, for example, a photo dose of 500 mJ/cm2 or less (using a 365 nm sensor). However, the photo dose may vary depending on the types of components of the curable composition, their combination ratios, and the dry film thickness.

(3) Imaging

After the exposure process, an alkaline aqueous solution is used to develop the exposed film by dissolving and removing unnecessary parts except for the exposed parts, thereby forming an image pattern. In other words, when an alkaline developing solution is used for development, the non-exposed area is dissolved and an image color filter pattern is formed.

(4) Post-processing

The developed image pattern can be cured again by heating or by irradiation with actinic rays and the like to achieve excellent qualities in terms of heat resistance, light resistance, close contact properties, crack resistance, chemical resistance, high strength, storage stability and the like.

Hereinafter, the present invention will be described in more detail with reference to examples. However, these examples are not to be construed as limiting the scope of the present invention in any sense.

Preparation of polymerizable compounds

Preparation Example 1

20 g of 2,2-thioethanol was placed in a flask and fully dissolved in 400 ml of dichloromethane. 32.6 g of acryloyl chloride was added thereto, and then stirred under a nitrogen atmosphere. 36.4 g of trimethylamine was injected thereto dropwise at 0°C for 1 hour, and then stirred for 2 hours to complete the reaction. 200 ml of dichloromethane and 500 ml of water were added thereto for extraction, and after separating the dichloromethane layer therefrom, dilute hydrochloric acid was added thereto to repeat the extraction three times. MgSO ₄ was added to the separated dichloromethane layer, and then stirred for 5 minutes. After filtering, the filtrate therefrom was concentrated. The obtained product was subjected to column chromatography and then concentrated and vacuum dried, thereby preparing a compound represented by Chemical Formula 1-1 (refractive index: 1.495).

Preparation Example 2

20 g of 3,6-dithia-1,8-octanedioic acid was placed in a flask and fully dissolved in 200 ml of dichloromethane and 200 ml of ethanol. 21.8 g of acryloyl chloride was added thereto, and then stirred under a nitrogen atmosphere. 24.4 g of trimethylamine was dropwise injected thereto at 0°C for 1 hour and stirred for 2 hours to complete the reaction. 200 ml of dichloromethane and 500 ml of water were added thereto for extraction, and after separating the dichloromethane layer therefrom, dilute hydrochloric acid was added thereto to repeat the extraction three times. MgSO ₄ was added to the separated dichloromethane layer, and then stirred for 5 minutes. After filtering, the filtrate therefrom was concentrated. The obtained product was subjected to column chromatography and then concentrated and vacuum dried, thereby preparing a compound represented by Chemical Formula 1-2 (refractive index: 1.529).

Preparation Example 3

20 g of 1,4-dithiane-2,5-diol was added to 300 ml of ethanol and 200 ml of dichloromethane, and then stirred. 26 g of acryloyl chloride was added thereto, and then stirred under a nitrogen atmosphere. 29.2 g of trimethylamine was injected dropwise thereto at 0°C for 1 hour and stirred for 2 hours to complete the reaction. 200 ml of dichloromethane and 500 ml of water were added thereto for extraction, and after separating the dichloromethane layer therefrom, dilute hydrochloric acid was added thereto to repeat the extraction three times. The separated dichloromethane layer was separated, and MgSO ₄ was added thereto, and then stirred for 5 minutes. After filtering, the filtrate therefrom was concentrated. The obtained product was subjected to column chromatography and then concentrated and vacuum dried, thereby preparing a compound represented by Chemical Formula 1-3 (refractive index: 1.680).

Preparation Example 4

100 g of 1,6-hexanediol was dissolved in 100 ml of toluene, and 135 g of acrylic acid and 8.2 g of methanesulfonic acid were added thereto, and then reacted at 120°C for 5 hours, thereby preparing a compound represented by Chemical Formula 2-2 (refractive index: 1.455).

Comparative preparation example 1

20 g of bis(2-hydroxyethyl)disulfide was fully dissolved in 300 ml of ethanol and 150 ml of dichloromethane. 25.7 g of acryloyl chloride was added thereto, and then stirred for 10 minutes. 28.8 g of triethylamine was slowly injected dropwise thereto, and then stirred at 0°C for 5 hours to complete the reaction, and 250 ml of dichloromethane and 300 ml of water were added thereto for extraction. The organic layer was separated, and extracted three times with a dilute hydrochloric acid aqueous solution. The dichloromethane layer was separated therefrom, MgSO ₄ was added thereto, and then stirred for 5 minutes. After filtering, the filtrate therefrom was concentrated. The obtained product was subjected to column chromatography and then concentrated and vacuum dried, thereby preparing a compound represented by Chemical Formula C-1 (refractive index: 1.517).

Comparative preparation example 2

20 g of 1,4-benzenedithiol was fully dissolved in 200 ml of dichloromethane. 22.5 g of 2-chloroethyl acrylate was added thereto, and then stirred for 10 minutes, and 17 g of triethylamine was slowly injected dropwise thereto at 0°C, and then stirred for 12 hours to complete the reaction. 300 ml of dichloromethane and 300 ml of water were added thereto for extraction, and after separation of the organic layer, a dilute hydrochloric acid solution was added thereto to repeat the extraction three times. The dichloromethane layer was separated therefrom, and MgSO ₄ was added thereto, and then stirred for 5 minutes. After filtration, the filtrate therefrom was concentrated. The obtained product was subjected to column chromatography and then concentrated and vacuum dried to prepare a compound represented by Chemical Formula C-2 (refractive index: 1.556).

Preparation of surface-modified quantum dot dispersions

Preparation Example 5

After placing a magnetic bar in a 3-neck round-bottom flask, a green quantum dot dispersion solution (InP/ZnSe/ZnS, quantum dot solid: 23% by weight, Hansol Chemical) was placed therein. A compound represented by the chemical formula Q (ligand) was added thereto, and then stirred at 80°C under a nitrogen atmosphere. After the reaction was completed and then cooled to room temperature (23°C), the quantum dot reaction solution was added to cyclohexane to capture the precipitate. The precipitate was separated from the cyclohexane by centrifugation and fully dried in a vacuum oven for 24 hours to obtain surface-modified quantum dots.

The surface-modified green quantum dots were stirred in the polymerizable compound for 12 hours to obtain a surface-modified quantum dot dispersion (QD solids: 23 wt%).

(*Synthesis of the compound represented by the chemical formula Q: 100 g of PH-4 (Hannong Chemical Inc.) was placed in a 2-neck round-bottom flask and then fully dissolved in 300 ml of THF. 15.4 g of NaOH and 100 ml of water were injected therein at 0°C and then fully dissolved until a clear solution was obtained.

A solution obtained by dissolving 73 g of p-toluenesulfonic acid chloride in 100 ml of THF was slowly injected thereinto at 0°C. The injection was performed for 1 hour, and the resulting mixture was stirred at room temperature for 12 hours. When the reaction was completed, an excess of dichloromethane was added thereto and then stirred, and a saturated solution of NaHCO ₃ was added thereto, followed by extraction, titration and dehydration. After removing the solvent, the residue was dried in a drying oven for 24 hours. 50 g of the dried product was placed in a 2-neck round-bottom flask and fully stirred in 300 ml of ethanol. Subsequently, 27 g of thiourea was added thereto and dispersed therein, and then refluxed at 80°C for 12 hours. Then, an aqueous solution prepared by dissolving 4.4 g of NaOH in 20 ml of water was injected thereto, and while stirring for another 5 hours, an excess of dichloromethane was added thereto, and then an aqueous hydrochloric acid solution was added thereto, followed by extraction, titration, dehydration, and solvent removal in sequence. The obtained product was dried in a vacuum oven for 24 hours, thereby obtaining a compound represented by the chemical formula Q. )

(Preparation of curable composition) Examples 1 to 7 and Comparative Examples 1 to 3

Each curable composition according to Examples 1 to 7 and Comparative Examples 1 to 3 was prepared by using the compositions shown in Tables 1 and 2.

Specifically, after weighing the quantum dot dispersion, it was diluted by mixing with the polymerizable compound, and a polymerization inhibitor was added and stirred for 5 minutes. Subsequently, a photoinitiator was added thereto, and a light diffuser was added thereto. Then, the corresponding crude liquid was stirred for 1 hour to prepare a curable composition.

(A) Quantum dots

Surface-modified green quantum dot dispersion prepared by Preparation Example 5

(B) Polymerizable compounds

(B-1) Preparation of the compound of Example 1

(B-2) Preparation of the compound of Example 2

(B-3) Preparation of the compound of Example 3

(B-4) Preparation of the compound of Example 4

(B-5) Comparison of the compounds of Preparation Example 1

(B-6) Comparison of the compounds of Preparation Example 2

(C) Photopolymerization initiator

TPO-L (Polynetron Co.)

(D) Light diffuser

Titanium dioxide dispersion ( _TiO2 solid content: 20% by weight, average particle size: 200 nm, Ditto technology)

(E)Polymerization inhibitor

Methylhydroquinone (TOKYO CHEMICAL)

Evaluation: Optical properties and diffuse reflectivity of curable compositions

The post-exposure quantum efficiency (EQE) and the post-curing diffuse reflectance (SCE) of each curable composition according to Examples 1 to 7 and Comparative Examples 1 to 3 were measured by using a spectrophotometer (CM-3600A, Konica Minolta Sensing Inc.), and the results are shown in Table 3.

Referring to Table 3, compared with the curable compositions according to Comparative Examples 1 to 3, the curable compositions according to Examples 1 to 7 exhibit higher post-exposure quantum efficiencies and thus exhibit improved optical properties, and at the same time exhibit lower post-curing diffuse reflectance and thus exhibit a reflectivity reduction effect.

Although the present invention has been described in conjunction with what are currently considered to be practical exemplary embodiments, it should be understood that the present invention is not limited to the disclosed embodiments, but rather, the present invention is intended to cover various modifications and equivalent configurations within the spirit and scope of the attached patent application. Therefore, the foregoing embodiments should be understood as exemplary, but not limiting the present invention in any way.

Claims (17)

A curable composition comprising: (A) quantum dots; and (B) a polymerizable compound comprising a compound represented by Chemical Formula 1:

Wherein, in Chemical Formula 1, ^L1 is represented by any one of Chemical Formulas L-2 to L-4:

Wherein, in Chemical Formula L-2 to Chemical Formula L-4, ^L4 is a substituted or unsubstituted C1 to C20 alkylene group, ^L5 to ^L8 are each independently a single bond or a substituted or unsubstituted C1 to C20 alkylene group, ^L2 and ^L3 are each independently a single bond, a substituted or unsubstituted C1 to C20 alkylene group, or a substituted or unsubstituted C3 to C20 cycloalkylene group, and ^R1 and ^R2 are each independently a hydrogen atom, a substituted or unsubstituted C1 to C20 alkyl group, a substituted or unsubstituted C3 to C20 cycloalkyl group, or a substituted or unsubstituted C6 to C20 aryl group. A curable composition as described in claim 1, wherein the compound represented by the chemical formula 1 has a refractive index less than or equal to 1.455. The curable composition of claim 1, wherein the compound represented by the chemical formula 1 is represented by any one of chemical formulas 1-2 to 1-3:

The curable composition as claimed in claim 1 further comprises a compound represented by Chemical Formula 2: [Chemical Formula 2]

Wherein, in the chemical formula 2, ^L9 is a substituted or unsubstituted C1 to C10 alkylene group or an ether group (*-O-*), ^L10 and ^L11 are each independently a substituted or unsubstituted C1 to C10 alkylene group, and ^R3 and ^R4 are each independently a hydrogen atom or a substituted or unsubstituted C1 to C20 alkyl group. A curable composition as described in claim 4, wherein the compound represented by the chemical formula 2 has a refractive index less than or equal to 1.455. The curable composition as described in claim 4, wherein the compound represented by the chemical formula 1 and the compound represented by the chemical formula 2 are contained in a weight ratio of 1:9 to 9:1. A curable composition as described in claim 1, wherein the curable composition is a solvent-free curable composition. The curable composition as described in claim 7, wherein the solvent-free curable composition comprises: 5 wt% to 60 wt% of the quantum dots; and 40 wt% to 95 wt% of the polymerizable compound, based on the total amount of the solvent-free curable composition. The curable composition as described in claim 1, wherein the curable composition further comprises a polymerization initiator, a light diffuser, a polymerization inhibitor, or a combination thereof. A curable composition as described in claim 9, wherein the light diffuser comprises barium sulfate, calcium carbonate, titanium dioxide, zirconium oxide or a combination thereof. A curable composition as described in claim 1, wherein the curable composition further comprises a solvent. The curable composition as claimed in claim 11, wherein the curable composition comprises 1 wt% to 40 wt% of the quantum dots, 1 wt% to 20 wt% of the polymerizable compound, and 40 wt% to 80 wt% of the solvent, based on the total weight of the curable composition. The curable composition as described in claim 1, wherein the curable composition further comprises malonic acid, 3-amino-1,2-propylene glycol, a silane coupling agent, a leveling agent, a fluorine-based surfactant or a combination thereof. A cured layer manufactured using a curable composition as described in any one of claims 1 to 13. A cured layer as described in claim 14, wherein the cured layer has a diffuse reflectivity of 50% to 55%. A color filter comprising a cured layer as described in claim 14. A display device comprising the color filter as described in claim 16.