Solventless curable composition, cured layer using the same, color filter including the cured layer, and display device

Abstract

Disclosed are a solvent-free curable composition including quantum dots and a curable monomer represented by Chemical Formula 1, a cured layer manufactured using the composition, a color filter including the cured layer, and a display device including the color filter. (In Chemical Formula 1, each substituent is as defined in the specification.) [Chemical Formula 1]

Description

TECHNICAL FIELD

[0001] The present disclosure relates to a solvent-free type curable composition, a cured layer manufactured using the same, a color filter including the cured layer, and a display device including the color filter. BACKGROUND

[0002] In the case of ordinary quantum dots, due to surface characteristics having hydrophobicity, solvents in which the quantum dots are dispersed are limited, and thus it is difficult to be introduced into a polar system such as an adhesive or a curable monomer.

[0003] For example, even in the case of actively researching quantum dot ink composition, the polarity is relatively low in the initial step and the solvent used can be dispersed in a curable composition having high hydrophobicity. Therefore, since it is difficult to include quantum dots in an amount of 20% by weight or more based on the total amount of the composition, it is not possible to increase the light efficiency of the ink to a certain degree or more. Even if quantum dots are additionally added and dispersed in order to increase the light efficiency, the viscosity exceeds the range capable of inkjet, and thus the processability can not be satisfied.

[0004] In order to achieve the viscosity range capable of inkjet, attempts have been made to reduce the ink solid content by dissolving 50% by weight or more of a solvent based on the total amount of the composition, which also provides a slightly satisfactory result in terms of viscosity. However, it can be considered as a satisfactory result in terms of viscosity, but nozzle drying due to solvent evaporation and nozzle clogging during inkjet, and reduction in the single layer thickness over time after inkjet can become worse, and it is difficult to control the thickness deviation after curing. Therefore, it is difficult to apply it to an actual process.

[0005] Therefore, a solvent-free type quantum dot ink not including a solvent is the most ideal form for application to an actual process. The current technology applying quantum dots themselves to a solvent type composition is now limited to a certain degree.

[0006] As reported so far, since the solvent type composition includes about 20% to about 25% by weight of non-surface modified quantum dots through ligand substitution and the like based on the total amount of the solvent type composition, and thus has a viscosity limitation, it is difficult to increase the light efficiency and the absorption rate. On the other hand, a method of reducing the content of quantum dots and increasing the content of a light diffusing agent (scatterer) has been attempted, but failed to improve the deposition problem or low light efficiency. SUMMARY

[0007] TECHNICAL CHALLENGES

[0008] An embodiment provides a solvent-free type curable composition including a curable monomer including a linking group having a substituent and a quantum dot.

[0009] Another embodiment provides a cured layer manufactured using a solvent-free curable composition.

[0010] Another embodiment provides a color filter including the cured layer.

[0011] Another embodiment provides a display device including the color filter.

[0012] Means for solving the problem

[0013] An embodiment provides a solvent-free curable composition including a quantum dot; and a curable monomer represented by Chemical Formula 1.

[0014] [Chemical Formula 1]

[0015]

[0016] In Chemical Formula 1,

[0017] R 1 and R 2 are each independently a hydrogen atom or a substituted or unsubstituted C1 to C10 alkyl,

[0018] L 1 is a single bond or an unsubstituted C1 to C20 alkylene,

[0019] L 2 is a substituted C1 to C20 alkylene, and

[0020] L 3 is a substituted or unsubstituted C1 to C20 alkylene.

[0021] Chemical Formula 1 can be represented by any one of Chemical Formula 1-1 to Chemical Formula 1-3.

[0022] [Chemical Formula 1-1]

[0023]

[0024] [Chemical Formula 1-2]

[0025]

[0026] [Chemical Formula 1-3]

[0027]

[0028] In Chemical Formula 1-1 to Chemical Formula 1-3,

[0029] R 1 and R 2 are each independently a hydrogen atom or a substituted or unsubstituted C1 to C10 alkyl,

[0030] L 4 is unsubstituted C1 to C20 alkylene,

[0031] L 5 to L 7 each independently substituted C1 to C20 alkylene, and

[0032] L 8 to L 10 each independently substituted or unsubstituted C1 to C20 alkylene, with the proviso that at least one of L 8 to L 10 must be substituted C1 to C20 alkylene.

[0033] The curable monomer represented by Chemical Formula 1 can have a vapor pressure of 1.0 x 10 -4 tor to 5.0 x 10 -2 tor. The curable monomer represented by Chemical Formula 1 can have a viscosity of 4 centipoise to 10 centipoise.

[0034] The curable monomer represented by Chemical Formula 1 can be represented by any one of Chemical Formula 2 to Chemical Formula 6.

[0035] [Chemical Formula 2]

[0036]

[0037] [Chemical Formula 3]

[0038]

[0039] [Chemical Formula 4]

[0040]

[0041] [Chemical Formula 5]

[0042]

[0043] [Chemical Formula 6]

[0044]

[0045] The solvent-free type curable composition can have a viscosity of 20 centipoise to 40 centipoise.

[0046] The quantum dot can have a maximum fluorescence emission wavelength in the range of 500 nanometers to 680 nanometers.

[0047] The solvent-free curable composition can include quantum dots in an amount of 5 to 60 wt% based on the total amount of the solvent-free curable composition; and 40 to 95 wt% of the curable monomer represented by Chemical Formula 1.

[0048] The solvent-free curable composition can further include a polymerization initiator, a light diffusing agent, or a combination thereof.

[0049] The light diffusing agent can include barium sulfate, calcium carbonate, titanium dioxide, zirconium oxide, or a combination thereof.

[0050] The solvent-free curable composition can further include a polymerization inhibitor, malonic acid, 3-amino-1,2-propanediol, a silane coupling agent, a leveling agent, a fluorine-based surfactant, or a combination thereof.

[0051] Another embodiment provides a cured layer manufactured using the solvent-free curable composition.

[0052] Another embodiment provides a color filter including the cured layer.

[0053] Another embodiment provides a display device including the color filter.

[0054] Other embodiments of the present invention are included in the following embodiments.

[0055] Effects of Invention

[0056] The present invention provides a solvent-free curable composition having excellent storage stability and excellent inkjet properties (even if the standing time is long) by modifying the structure of the curable monomer to include a linker having a substituent to reduce the viscosity of itself and a composition including the same, and thus improving the inkjet properties. BRIEF DESCRIPTION OF DRAWINGS

[0057] Figure 1 A photograph showing the solvent-free curable composition of Example 1 immediately after inkjet.

[0058] Figure 2 A photograph showing the solvent-free curable composition of Example 1 immediately after inkjet of 10 minutes of standing time.

[0059] Figure 3 A photograph showing the solvent-free curable composition according to Example 1 immediately after inkjet of 30 minutes of standing time.

[0060] Figure 4 A photograph showing the solvent-free curable composition according to Example 1 immediately after inkjet of 60 minutes of standing time.

[0061] Figure 5A photograph of inkjet immediately after 24 hours of dwell time for the solventless curable composition according to Example 1.

[0062] Figure 6 A photograph of inkjet immediately after 24 hours of dwell time for the solventless curable composition according to Example 1.

[0063] Figure 7 A photograph of inkjet immediately after 10 minutes of dwell time for the solventless curable composition according to Comparative Example 1.

[0064] Figure 8 A photograph of inkjet immediately after 30 minutes of dwell time for the solventless curable composition according to Comparative Example 1.

[0065] Best mode for carrying out the invention

[0066] Hereinafter, embodiments of the present application are described in detail. However, such embodiments are illustrative only, the present application is not limited thereto and the present application is defined only by the scope of the claims.

[0067] As used herein, when a specific definition is not otherwise provided, "alkyl" means C1 to C20 alkyl, "alkenyl" means C2 to C20 alkenyl, "cycloalkenyl" means C3 to C20 cycloalkenyl, "heterocycloalkenyl" means C3 to C20 heterocycloalkenyl, "aryl" means C6 to C20 aryl, "aralkyl" means C6 to C20 aralkyl, "alkylene" means C1 to C20 alkylene, "arylene" means C6 to C20 arylene, "alkylarylene" means C6 to C20 alkylarylene, "heteroarylene" means C3 to C20 heteroarylene, and "alkyloxy" means C1 to C20 alkyloxy.

[0068] As used herein, when a specific definition is not otherwise provided, the term "substituted" means that at least one hydrogen atom is replaced with a substituent selected from 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 imine group, a diazo group, a formamidine group, a hydrazine group, a hydrazo group, a carbonyl group, a carboxamide group, a thiol group, an ester group, an ether group, a carboxyl group or a salt thereof, a sulfonic acid group or a salt thereof, a phosphoric acid or a salt thereof, a C1 to C20 alkyl group, a C2 to C20 alkenyl group, a C2 to C20 alkynyl group, a C6 to C20 aryl group, a C3 to C20 cycloalkyl group, a C3 to C20 cycloalkenyl group, a C3 to C20 cycloalkynyl group, a C2 to C20 heterocycloalkyl group, a C2 to C20 heterocycloalkenyl group, a C2 to C20 heterocycloalkynyl group, a C3 to C20 heteroaryl group, or a combination thereof.

[0069] As used herein, when a specific definition is not otherwise provided, "hetero" means that at least one heteroatom N, O, S, and P is included in the chemical formula.

[0070] As used herein, "(meth)acrylate" refers to both "acrylate" and "methacrylate", and "(meth)acrylic acid" refers to both "acrylic acid" and "methacrylic acid", when a specific definition is not otherwise provided.

[0071] As used herein, the term "combination" refers to mixing or copolymerization, when a specific definition is not otherwise provided.

[0072] In the present specification, when a chemical bond is not drawn at a position where it should be given in a chemical formula, hydrogen is bonded at the position, when a definition is not otherwise provided.

[0073] Further, in the present specification, "*" refers to a point of attachment to the same or different atom or chemical formula, when a definition is not otherwise provided.

[0074] The present application relates to a curable composition for a color filter applied to a display device, and in particular, a solvent-free curable ink composition including quantum dots, which has recently been established as a new technology in the display field.

[0075] A quantum dot-containing photosensitive ink composition applied to a quantum dot display is generally composed of a curable monomer, a binder resin, a starter, a solvent, an additive, and the like, and in addition, includes quantum dots and a light diffusing agent to secure color characteristics, in which the quantum dots have a function of converting incident light into red and green light after forming a single film.

[0076] However, when the quantum dot-containing photosensitive ink composition includes a solvent, there are problems such as nozzle drying, nozzle clogging, post-jet single layer film reduction, and the like caused by solvent evaporation during inkjet, and in addition, due to a severe thickness deviation after curing, recent research has been actively conducted on a quantum dot-containing curable ink composition that does not use a solvent, that is, a solvent-free curable ink composition.

[0077] The solvent-free quantum dot-containing curable ink composition includes a multifunctional monomer in order to sufficiently disperse quantum dots and sufficiently form a matrix through UV curing or thermal curing. In particular, a widely used HDDA (1,6-hexanediol diacrylate) monomer has a viscosity of about 6.2 centipoise, and when prepared into a curable ink composition, the viscosity becomes about 26.3 centipoise. In order to apply this curable ink composition having a relatively high viscosity to a process, the curable ink composition should be jetted after reducing the viscosity of the ink composition by increasing the temperature of a nozzle head during inkjet. However, when the temperature of the nozzle head is increased, problems such as nozzle clogging in the nozzle head, insufficient ejection, and the like caused by the increase in temperature occur.

[0078] Accordingly, the present inventors developed a solvent-free curable composition which is capable of dispersing quantum dots as well as conventional monomers such as HDDA and thus sufficiently forms a matrix via UV curing or thermal curing, minimizes quantum efficiency deterioration of quantum dots after exposure and thermal processes, and further maintains storage stability and inkjet properties during a long residence time.

[0079] Hereinafter, each component constituting the solvent-free curable composition is described in detail.

[0080] Curable monomer

[0081] The curable monomer included in the solvent-free curable composition according to the embodiment is a monomer having carbon-carbon double bonds at both terminals, and specifically is represented by Chemical Formula 1.

[0082] [Chemical Formula 1]

[0083]

[0084] In Chemical Formula 1,

[0085] R 1 and R 2 each independently is a hydrogen atom or a substituted or unsubstituted C1 to C10 alkyl group,

[0086] L 1 is a single bond or an unsubstituted C1 to C20 alkylene group,

[0087] L 2 is a substituted C1 to C20 alkylene group, and

[0088] L 3 is a substituted or unsubstituted C1 to C20 alkylene group.

[0089] The curable monomer represented by Chemical Formula 1 must include a substituent such as an alkyl group and the like in the linking group included between the (meth)acrylate groups included at both terminals, which can reduce the viscosity of the curable monomer represented by Chemical Formula 1 itself and also reduce the viscosity of the solvent-free curable composition including the same, and thus significantly improves the inkjet properties of the composition and further contributes to minimizing quantum efficiency deterioration of quantum dots described later after exposure and thermal processes.

[0090] In addition, the solvent-free curable composition of the embodiment includes the curable monomer represented by Chemical Formula 1, and thus can exhibit almost no change in viscosity over time at a higher temperature higher than room temperature, and thus has excellent storage stability, and maintains inkjet properties without deterioration even if the residence time during the inkjet process is extended.

[0091] For example, the curable monomer 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.

[0092] [Chemical Formula 1-1]

[0093]

[0094] [Chemical Formula 1-2]

[0095]

[0096] [Chemical Formula 1-3]

[0097]

[0098] In Chemical Formula 1-1 to Chemical Formula 1-3,

[0099] R 1 and R 2 each independently is a hydrogen atom or a substituted or unsubstituted C1 to C10 alkyl,

[0100] L 4 is an unsubstituted C1 to C20 alkylene,

[0101] L 5 to L 7 each independently is a substituted C1 to C20 alkylene, and

[0102] L 8 to L 10 each independently is a substituted or unsubstituted C1 to C20 alkylene, with the proviso that at least one of L 8 to L 10 must be a substituted C1 to C20 alkylene.

[0103] For example, the curable monomer represented by Chemical Formula 1 can have a vapor pressure of 1.0 x 10 -4 tor to 5.0 x 10 -2 tor.

[0104] For example, the curable monomer represented by Chemical Formula 1 can have a viscosity of 4 centipoise to 10 centipoise.

[0105] For example, the curable monomer represented by Chemical Formula 1 can be represented by any one of Chemical Formula 2 to Chemical Formula 6, but is not necessarily limited thereto.

[0106] [Chemical Formula 2]

[0107]

[0108] [Chemical Formula 3]

[0109]

[0110] [Chemical Formula 4]

[0111]

[0112] [Chemical Formula 5]

[0113]

[0114] [Chemical Formula 6]

[0115]

[0116] For example, the solvent-free curable composition can have a viscosity of 20 to 40 centipoise.

[0117] The curable monomer represented by Chemical Formula 1 can be included in an amount of 40 to 95% by weight, for example, 45 to 90% by weight, for example, 45 to 85% by weight, or for example, 50 to 80% by weight, based on the total weight of the solvent-free curable composition. When the content of the curable monomer represented by Chemical Formula 1 is within the above range, a solvent-free curable composition having a viscosity capable of inkjet can be prepared, and the quantum dots in the prepared solvent-free curable composition can also have excellent dispersibility, and thus optical properties can also be improved.

[0118] For example, the curable monomer represented by Chemical Formula 1 can have a molecular weight of 180 to 1,000 g / mol. When the molecular weight of the curable monomer represented by Chemical Formula 1 is within the above range, inkjet can be facilitated in that the viscosity of the composition is not increased without inhibiting the optical properties of the quantum dots.

[0119] In addition, the solvent-free curable composition according to the embodiments can further include a monomer generally used in a conventional thermosetting or photocurable composition, in addition to the curable monomer represented by Chemical Formula 1, and the monomer can further include, for example, an oxetane compound such as bis[1-ethyl(3-oxetanyl)]methyl ether.

[0120] Quantum dots

[0121] For example, the quantum dots included in the solvent-free curable composition absorb light in a wavelength range of 360 to 780 nm, for example, 400 to 780 nm, and emit fluorescence in a wavelength range of 500 to 700 nm, for example, 500 to 580 nm, or emit fluorescence in a wavelength range of 600 to 680 nm. That is, the quantum dots can have a maximum fluorescence emission wavelength (fluorescence λ em ).

[0122] The quantum dots can 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 the range of the full width at half maximum (FWHM), color reproducibility is increased when used as a color material in a color filter due to high color purity.

[0123] The quantum dots can independently be an organic material, an inorganic material, or a hybrid of an organic material and an inorganic material.

[0124] The quantum dots can independently consist of a core and a shell layer surrounding the core, and the core and the shell layer can independently have a structure of a core, a core / shell layer, a core / first shell layer / second shell layer, an alloy, an alloy / shell layer, or the like, consisting of Groups II to IV, Groups III to V, and the like, but are not limited thereto.

[0125] For example, the core can include at least one material selected from CdS, CdSe, CdTe, ZnS, ZnSe, ZnTe, HgS, HgSe, HgTe, GaN, GaP, GaAs, InP, InAs, and alloys thereof, but is not necessarily limited thereto. The shell layer surrounding the core can include at least one material selected from CdSe, ZnSe, ZnS, ZnTe, CdTe, PbS, TiO, SrSe, HgSe, and alloys thereof, but is not necessarily limited thereto.

[0126] In an embodiment, since recent worldwide concerns about the environment have greatly increased and restrictions on toxic materials have also been strengthened, a cadmium-free light-emitting material (InP / ZnS, InP / ZeSe / ZnS, etc.) having slightly lower quantum efficiency (quantum yield) but being environmentally friendly is used instead of a light-emitting material having a cadmium-based core, but is not necessarily limited thereto.

[0127] In the case of a quantum dot of a core / shell layer structure, the overall size (average particle diameter) including the shell layer can be 1 nm to 15 nm, for example, 5 nm to 15 nm.

[0128] For example, the quantum dots can independently include red quantum dots, green quantum dots, or a combination thereof. The red quantum dots can independently have an average particle diameter of 10 nm to 15 nm. The green quantum dots can independently have an average particle diameter of 5 nm to 8 nm.

[0129] On the other hand, for dispersion stability of the quantum dots, the solvent-free curable composition according to the embodiments can further include a dispersant to include the quantum dots in the form of a quantum dot dispersion liquid. The dispersant contributes to uniform dispersibility of the photoconversion material such as the quantum dots in the solvent-free curable composition, and can include a nonionic, anionic, or cationic dispersant. In particular, the dispersant can be a polyalkylene glycol or an ester thereof, a polyoxyalkylene, a polyhydric alcohol ester alkylene oxide adduct, an ethanol alkylene oxide adduct, a sulfonate ester, a sulfonate salt, a carboxylate ester, a carboxylate salt, an alkylamide alkylene oxide adduct, an alkylamine, and the like, and can be used alone or in a mixture of two or more. The dispersant can be used in an amount of 0.1 to 100% by weight, for example, 10 to 20% by weight, based on the solid content of the photoconversion material such as the quantum dots.

[0130] The quantum dots can be surface-modified by a conventional quantum dot surface-modification material (e.g., a thiol-based compound, etc.) or can not be surface-modified thereby.

[0131] The quantum dots can be included in an amount of 5 to 60% by weight, for example, 10 to 60% by weight, for example, 20 to 50% by weight, or for example, 30 to 50% by weight, based on the total amount of the solvent-free curable composition. When the quantum dots (e.g., quantum dot dispersion liquid) are included within the above range, the conversion rate is improved and the pattern characteristics and development characteristics are not deteriorated, and thus excellent processability can be obtained.

[0132] Polymerization initiator

[0133] The solvent-free curable composition according to the embodiments can further include a polymerization initiator, for example, a photopolymerization initiator, a thermal polymerization initiator, or a combination thereof.

[0134] The photopolymerization initiator can be a commonly used initiator for a photosensitive resin composition, for example, an acetophenone-based compound, a benzophenone-based compound, a thioxanthone-based compound, a benzoin-based compound, a triazine-based compound, an oxime-based compound, an aminoketone-based compound, and the like, but is not necessarily limited thereto.

[0135] Examples of the acetophenone-based compound can be 2,2'-diethoxyacetophenone, 2,2'-dibutoxyacetophenone, 2-hydroxy-2-methylpropiophenone, p-tert-butyltrichloroacetophenone, p-tert-butyl-dichloroacetophenone, 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.

[0136] Examples of benzophenone compounds can be 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.

[0137] Examples of thioxanthone compounds can be thioxanthone, 2-methylthioxanthone, isopropyl thioxanthone, 2,4-diethylthioxanthone, 2,4-diisopropylthioxanthone, 2-chlorothioxanthone, and the like.

[0138] Examples of benzoin compounds can be benzoin, benzoin methyl ether, benzoin ethyl ether, benzoin isopropyl ether, benzoin isobutyl ether, benzyl dimethyl ketal, and the like.

[0139] Examples of triazine compounds can be 2,4,6-trichloromelamine, 2-phenyl-4,6-bis(trichloromethyl) melamine, 2-(3',4'-dimethoxystyryl)-4,6-bis(trichloromethyl) melamine, 2-(4'-methoxynaphthyl)-4,6-bis(trichloromethyl) melamine, 2-(p-methoxyphenyl)-4,6-bis(trichloromethyl) melamine, 2-(p-tolyl)-4,6-bis(trichloromethyl) melamine, 2-biphenyl-4,6-bis(trichloromethyl) melamine, bis(trichloromethyl)-6-styrylmelamine, 2-(naphthol 1-yl)-4,6-bis(trichloromethyl) melamine, 2-(4-methoxynaphthol 1-yl)-4,6-bis(trichloromethyl) melamine, 2-4-bis(trichloromethyl)-6-piperonylmelamine, 2-4-bis(trichloromethyl)-6-(4-methoxystyryl) melamine, and the like.

[0140] Examples of oxime compounds can be 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-alpha-hydroxylamino-1-phenylpropan-1-one, and the like. Specific examples of O-acyl oxime compounds can be 1,2-octanedione, 2-dimethylamino-2-(4-methylbenzyl)-1-(4-morpholin-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)-octan-1-one oxime-O-acetate, 1-(4-phenylthiophenyl)-butan-1-one oxime-O-acetate, and the like.

[0141] Examples of the aminoketone compound can be 2-benzyl-2-dimethylamino-1- (4-morpholinophenyl) butanone-1 and the like.

[0142] In addition to the compound, the photopolymerization initiator can further include a carbazole compound, a diketone compound, a sulfonium borate compound, a diazo compound, an imidazole compound, a bisimidazole compound, and the like.

[0143] The photopolymerization initiator can be used together with a photosensitizer capable of causing a chemical reaction by absorbing light and becoming an excited state and then transferring its energy.

[0144] Examples of the photosensitizer can be tetraethylene glycol bis-3-mercaptopropionate, isopentyldiol tetra-3-mercaptopropionate, diisopentyldiol penta-3- mercaptopropionate, and the like.

[0145] Examples of the thermal polymerization initiator can be peroxides, in particular, benzoyl peroxide, dibenzoyl peroxide, lauroyl peroxide, di-lauroyl peroxide, di-tert-butyl peroxide, cyclohexane peroxide, methyl ethyl ketone peroxide, hydrogen peroxide (e.g., tert-butyl hydroperoxide, cumene hydroperoxide), di-cyclohexyl peroxydicarbonate, 2,2-azobis(isobutyronitrile), tert-butyl perbenzoate, and the like, such as 2,2'-azobis-2-methylpropionitrile, but not necessarily limited thereto, and any of the peroxides well known in the art can be used.

[0146] The polymerization initiator can be included in an amount of 0.1 to 5% by weight, for example, 1 to 4% by weight, based on the total amount of the solvent-free type 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 thermal curing, and it is possible to prevent transmittance deterioration due to non-reactive initiators, thereby preventing optical property deterioration of the quantum dots.

[0147] Light diffusing agent

[0148] The solvent-free type curable composition according to the embodiments can further include a light diffusing agent.

[0149] For example, the light diffusing agent can include barium sulfate (BaSO4), calcium carbonate (CaCO3), titanium dioxide (TiO2), zirconium oxide (ZrO2), or a combination thereof.

[0150] The light diffusing agent can reflect light not absorbed in the aforementioned quantum dots and allow the quantum dots to absorb the reflected light again. That is, the light diffusing agent can increase the amount of light absorbed by the quantum dots, and improve the light conversion efficiency of the curable composition.

[0151] The light diffusing agent can have an average particle diameter (D50) of 150 nm to 250 nm, and specifically 180 nm to 230 nm. 50 When the average particle diameter of the light diffusing agent is within the range, it can have a better light diffusing effect and improve the light conversion efficiency.

[0152] The light diffusing agent can be included in an amount of 1% by weight to 20% by weight, for example, 5% by weight to 10% by weight, based on the total amount of the solvent-free curable composition. When the light diffusing agent is included in an amount of 1% by weight, based on the total amount of the solvent-free curable composition, it is difficult to expect an effect of improving the light conversion efficiency by using the light diffusing agent, and when the light diffusing agent is included in an amount of more than 20% by weight, the quantum dots can be precipitated.

[0153] Other additives

[0154] The solvent-free curable composition according to the embodiments can further include a polymerization inhibitor for stability and dispersion improvement of the quantum dots.

[0155] The polymerization inhibitor can include a hydroquinone-based compound, a catechol-based compound, or a combination thereof, but is not necessarily limited thereto. When the solvent-free curable composition according to the embodiments further includes a hydroquinone-based compound, a catechol-based compound, or a combination thereof, room temperature crosslinking during exposure after coating the solvent-free curable composition can be prevented.

[0156] For example, the hydroquinone-based compound, the catechol-based compound, or the combination thereof can include hydroquinone, methylhydroquinone, methoxyhydroquinone, tertiary butylhydroquinone, 2,5-di-t-butylhydroquinone, 2,5-bis(1,1-dimethylbutyl)hydroquinone, 2,5-bis(1,1,3,3-tetramethylbutyl)hydroquinone, catechol, tertiary butylcatechol, 4-methoxyphenol, pyrogallol, 2,6-di-t-butyl-4-methylphenol, 2-naphthol, aluminum bis(N-hydroxy-N-nitrosophenylazanato-O,O'), or a combination thereof, but is not necessarily limited thereto.

[0157] The hydroquinone-based compound, the catechol-based compound, or the combination thereof can be used in the form of a dispersion liquid, and the polymerization inhibitor in the form of a dispersion liquid can be included in an amount of 0.001% by weight to 3% by weight, for example, 0.1% by weight to 2% by weight, based on the total amount of the solvent-free curable composition. When the polymerization inhibitor is included within the above range, the problem of aging at room temperature can be solved, and at the same time, a decrease in sensitivity and surface peeling can be prevented.

[0158] Further, the solventless curable composition according to embodiments can further include malonic acid; 3-amino 1,2-propanediol; a silane-based coupling agent; a leveling agent; a fluoroalkyl-based surfactant; or a combination thereof, in order to improve heat resistance and reliability.

[0159] For example, the solventless curable composition according to embodiments can further include a silane-based coupling agent having a reactive substituent such as a vinyl group, a carboxyl group, a methacryloyloxy group, an isocyanate group, an epoxy group, and the like, in order to improve close contact properties with a substrate.

[0160] Examples of the silane-based coupling agent can be trimethoxysilylbenzoic acid, γ-methacryloylpropyitrimethoxysilane, vinyltriacetoxysilane, vinyltrimethoxysilane, γ-isocyanatopropyltriethoxysilane, γ-glycidoxypropyltrimethoxysilane, β-epoxycyclohexyl)ethyltrimethoxysilane, and the like, and such silane-based coupling agents can be used alone or in a mixture of two or more.

[0161] The silane-based coupling agent can be included in an amount of 0.01 parts by weight to 10 parts by weight, based on 100 parts by weight of the solventless curable composition. When the silane-based coupling agent is included within the range, close contact properties, storage ability, and the like are improved.

[0162] Further, the solventless curable composition can further include a surfactant, for example, a fluoroalkyl-based surfactant, as necessary, in order to improve coating properties and inhibit the generation of spots, that is, to improve leveling efficiency.

[0163] The fluoroalkyl-based surfactant can 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. Further, the fluoroalkyl-based surfactant can have a surface tension (measured with a 0.1% polyethylene glycol monomethylether acetate (PGMEA) solution) of 18 mN / m to 23 mN / m. When the fluoroalkyl-based surfactant has a weight average molecular weight and a surface tension within the range, leveling efficiency can be further improved, and when applied as slit coating of high speed coating, excellent characteristics can be provided because film defects can be less generated by preventing the generation of spots and inhibiting vapor generation during high speed coating.

[0164] Examples of the fluoroalkyl-based surfactant can be and (BM Chemie Inc.); MEGAFACE F MEGAFACE F Majestif F and Majestif F (FULORAD) FULORAD FULORAD and FULORAD (SURFLON) SURFLON SURFLON SURFLON and SURFLON (ASAHI Glass Co., Ltd.) and and the like (Toray Silicone Co., Ltd.); F-482, F-484, F-478, F-554, and the like from DIC Co., Ltd.

[0165] In addition, the solventless curable composition according to the embodiments can include a silicone-based surfactant, in addition to the fluorine-based surfactant. Specific examples of the silicone-based surfactant can be TSF400, TSF401, TSF410, TSF4440, and the like of Toshiba Silicone Co., Ltd., but are not limited thereto.

[0166] The surfactant can 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 solventless curable composition. When the surfactant is included within the range, foreign substances generated in the spray composition are less.

[0167] In addition, the solventless curable composition according to the embodiments can further include other additives, such as an antioxidant, a stabilizer, and the like, in a predetermined amount, unless the properties are deteriorated.

[0168] Another embodiment provides a cured layer manufactured using the solventless curable composition and a color filter including the cured layer.

[0169] One of the methods of manufacturing the cured layer can include coating the solventless curable composition on a substrate using an inkjet spray method to form a pattern (S1), and curing the pattern (S2).

[0170] (S1) forming a pattern

[0171] It is desirable to coat the solventless curable composition on a substrate by an inkjet spraying method to be about 0.5 micrometers to about 20 micrometers. The inkjet spraying method can form a pattern by spraying a single color according to each nozzle and thus repeating spraying multiple times according to the number of desired colors, but can form a pattern by spraying the number of desired colors at the same time through each inkjet nozzle to reduce the process.

[0172] (S2) curing

[0173] The obtained pattern is cured to obtain a pixel. Herein, the curing method can be a thermal curing process or a photo curing process. The thermal curing process can be performed at higher than or equal to 100°C, desirably in the range of 100°C to 300°C, and more desirably in the range of 160°C to 250°C. The photo curing process can include irradiating actinic rays such as UV rays of 190 nm to 450 nm, for example, 200 nm to 500 nm. The irradiation is performed by using a light source such as a mercury lamp having low, high, or super high pressure, a metal halide lamp, an argon laser, and the like. X-rays, electron beams, and the like can also be used as needed.

[0174] Another method of manufacturing a cured layer can include manufacturing a cured layer by using the aforementioned solventless curable composition through a lithography method.

[0175] (1) coating and film formation

[0176] The solventless curable composition is coated using a spin coating or slit coating method, a roll coating method, a screen printing method, a painting method, and the like, to have a desired thickness, for example, a thickness in the range of about 2 micrometers to about 10 micrometers, on a substrate subjected to a predetermined pretreatment. 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.

[0177] (2) exposure

[0178] After placing a mask having a predetermined shape, the resulting film is irradiated by actinic rays such as UV rays of 190 nm to 450 nm, for example, 200 nm to 500 nm, to form a desired pattern. The irradiation is performed by using a light source such as a mercury lamp having low, high, or super high pressure, a metal halide lamp, an argon laser, and the like. X-rays, electron beams, and the like can also be used as needed.

[0179] When a high-pressure mercury lamp is used, the exposure process uses a light dose of, for example, 500 mJ / cm2or less (with a 365-nm sensor). However, the light dose can vary depending on the type of each component of the curable composition, the combined ratio thereof, and the dry film thickness.

[0180] (3) Developing

[0181] After the exposure process, the exposed film is developed by dissolving and removing unnecessary portions other than the exposed portions using an aqueous alkali solution, thereby forming an image pattern. In other words, when an alkali developing solution is used for development, the non-exposed regions are dissolved and an image color filter pattern is formed.

[0182] (4) Post-treatment

[0183] The developed image pattern can be heated again or irradiated by actinic rays and the like to be cured, so as to achieve excellent quality in terms of heat resistance, light resistance, close contact properties, crack resistance, chemical resistance, high strength, storage stability, and the like.

[0184] Another embodiment provides a display device including a color filter, for example, a display device such as an LCD, an LED, or an OLED. DETAILED DESCRIPTION

[0185] Hereinafter, the present application is explained in more detail with reference to examples. However, these examples are not to be construed as limiting the scope of the present application in any manner.

[0186] (Synthesis of curable monomer)

[0187] Synthesis Example 1

[0188] In a round bottom flask, 10 g of 3-methyl 1,5-pentanediol was dissolved in 100 g of cyclohexane. Subsequently, 3.4 g of acrylic acid and 2.4 g of methanesulfonic acid were added thereto and reacted at 100°C for 20 hours, thereby synthesizing a curable monomer represented by Chemical Formula 2 (molecular weight: 226 g / mol, vapor pressure at 25°C: 2.0 x 10 -3 mmHg).

[0189] [Chemical Formula 2]

[0190]

[0191] Synthesis Example 2

[0192] In a round bottom flask, 10 g of 2,3-butanediol was dissolved in 100 g of cyclohexane. Subsequently, 17.6 g of acrylic acid and 3.2 g of methanesulfonic acid were added thereto and reacted at 100°C for 20 hours, thereby synthesizing a curable monomer represented by Chemical Formula 3 (molecular weight: 198 g / mol).

[0193] [Chemical Formula 3]

[0194]

[0195] Synthesis Example 3

[0196] In a round-bottom flask, 10 g of 1,2-pentanediol was dissolved in 100 g of cyclohexane. Subsequently, 15.2 g of acrylic acid and 2.8 g of methanesulfonic acid were added thereto and reacted at 100°C for 20 hours, thereby synthesizing a curable monomer represented by Chemical Formula 4 (molecular weight: 212 g / mol).

[0197] [Chemical Formula 4]

[0198]

[0199] Synthesis Example 4

[0200] In a round-bottom flask, 10 g of 1,2-pentanediol was dissolved in 100 g of cyclohexane. Subsequently, 15.2 g of acrylic acid and 2.8 g of methanesulfonic acid were added thereto and reacted at 100°C for 20 hours, thereby synthesizing a curable monomer represented by Chemical Formula 4 (molecular weight: 212 g / mol).

[0201] [Chemical Formula 4]

[0202]

[0203] Synthesis Example 4

[0204] In a round-bottom flask, 10 g of 1,2-pentanediol was dissolved in 100 g of cyclohexane. Subsequently, 15.2 g of acrylic acid and 2.8 g of methanesulfonic acid were added thereto and reacted at 100°C for 20 hours, thereby synthesizing a curable monomer represented by Chemical Formula 4 (molecular weight: 212 g / mol).

[0205] [Chemical Formula 4]

[0206]

[0207] Evaluation 1: Viscosity measurement of curable monomer

[0208] The initial viscosity of the curable monomer of Synthesis Example 1 and HDDA (1,6-hexanediol diacrylate) (MIRAMER M200, Miwon Specialty Chemical Co., Ltd.) (vapor pressure at 25°C: 1.0 x 10 -3 mmHg) at 25°C was measured by using a viscometer (C60 / 1 spindle, shear rate: 600, HAAKE Rotoviscometer 6000, Thermo Fisher Scientific Inc.), and the results are shown in Table 1.

[0209] (Table 1)

[0210] Viscosity (centipoise) Curable monomer of synthesis example 1 5.0 HDDA 6.2

[0211] As shown in Table 1, the curable monomer of Synthesis Example 1 including a linking group having a substituent exhibited a lower viscosity compared to HDDA including a linking group having no substituent.

[0212] (Preparation of surface-modified quantum dots)

[0213] Preparation Example

[0214] After placing a magnetic bar in a 3-necked round bottom flask, a green quantum dot dispersion solution (InP / ZnSe / ZnS, Hansol Chemical; quantum dot solid content of 23 wt%) was placed therein. A compound represented by Chemical Formula Q (ligand) was added thereto, and then stirring was performed at 80°C under a nitrogen atmosphere. When the reaction was completed, after reducing the temperature to room temperature (23°C), the quantum dot reaction solution was added to cyclohexane, thereby capturing a precipitate. The precipitate was separated from the cyclohexane through centrifugation, and then sufficiently dried in a vacuum oven for one day, thereby obtaining surface-modified quantum dots.

[0215] (*Synthesis of a compound represented by Chemical Formula Q: 100 g of PH-4 (Hannong Chemical Inc.) was placed in a 2-necked round bottom flask, and then sufficiently dissolved in 300 mL of THF. 15.4 g of NaOH and 100 mL of water were injected thereto at 0°C, and then sufficiently 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 thereto at 0°C. The injection was performed for 1 hour, and the obtained mixture was stirred at room temperature for 12 hours. When the reaction was completed, excess dichloromethane was added thereto and then stirred, and a saturated NaHCO3 solution was added thereto, followed by extraction, titration, and dehydration. After removing the solvent, the residue was dried in a dry oven for 24 hours. 50 g of the dried product was placed in a 2-necked round bottom flask and sufficiently 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. Next, an aqueous solution prepared by dissolving 4.4 g of NaOH in 20 mL of water was injected thereto while additionally stirring for 5 hours, excess 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 Chemical Formula Q.)

[0216] [Chemical Formula Q]

[0217]

[0218] (Preparation of solvent-free curable composition)

[0219] Example 1

[0220] A quantum dot dispersion liquid was obtained by mixing the green quantum dot solid of the example with the curable monomer synthesized in Example 1 in the same weight ratio and stirring the mixture for 12 hours.

[0221] The curable monomer synthesized in Example 1 was added to the quantum dot dispersion liquid for dilution, and then a polymerization inhibitor (methyl hydroquinone, Tokyo Chemical Industry Co., Ltd.) was added thereto, and then stirred for 5 minutes. Subsequently, a photoinitiator (TPO-L, Polynetron Co., Ltd.) was added thereto, and a light diffusing agent (Ti02 of rutile type; particle diameter: 180 nm) was added thereto. Then, the corresponding crude liquid was stirred for 1 hour, thereby preparing a solvent-free curable composition. The solvent-free curable composition had the composition shown in Table 2. (As an example, a solvent-free curable composition was prepared by mixing 40 grams of the green quantum dot solid with 40 grams of the curable monomer synthesized in Example 1 to prepare a quantum dot dispersion liquid, adding 10.5 grams of the curable monomer synthesized in Example 1 and 0.5 grams of a polymerization inhibitor to the quantum dot dispersion liquid, and then stirring the mixture for 5 minutes, and subsequently adding 3 grams of a photoinitiator and 4 grams of a light diffusing agent thereto, which was stirred.)

[0222] (Table 2)

[0223] (Unit: gram)

[0224] Content Quantum dot solids content 40 Curable monomer (synthesis example 1) 50.5 Polymerization inhibitor 0.5 Photoinitiator 3 Light diffuser 4

[0225] Example 2

[0226] A solvent-free curable composition was prepared according to the same method as Example 1 except that the curable monomer synthesized in Example 2 was used instead of the curable monomer synthesized in Example 1.

[0227] Example 3

[0228] A solvent-free curable composition was prepared according to the same method as Example 1 except that the curable monomer synthesized in Example 3 was used instead of the curable monomer synthesized in Example 1.

[0229] Example 4

[0230] A solvent-free curable composition was prepared according to the same method as Example 1 except that the curable monomer synthesized in Example 4 was used instead of the curable monomer synthesized in Example 1.

[0231] Example 5

[0232] A solvent-free curable composition was prepared according to the same method as Example 1 except that the curable monomer of Synthesis Example 5 was used instead of the curable monomer of Synthesis Example 1.

[0233] Comparative Example 1

[0234] A solvent-free curable composition was prepared according to the same method as Example 1 except that HDDA (1,6-hexanediol diacrylate) was used instead of the curable monomer of Synthesis Example 1.

[0235] Evaluation 2: Evaluation of optical properties

[0236] The solvent-free curable compositions according to Example 1 and Comparative Example 1 were each coated to a thickness of 15 micrometers on a yellow photoresist (YPR) using a spin coater (830 rpm, 5 seconds, Opticoat MS-A150, Mikasa Co., Ltd.) under a nitrogen atmosphere using a UV exposure device at 395 nanometers, and exposed to light at 5000 mJ (83°C, 10 seconds). Subsequently, a 2 cm x 2 cm single layer film sample was loaded into an integrating sphere apparatus (QE-2100, Otsuka Electronics, Co., Ltd.) to measure the external quantum efficiency of the quantum dots (external quantum efficiency after exposure). Next, the loaded single layer film sample was dried (heat treated) in a nitrogen atmosphere drying oven at 180°C for 30 minutes, and again measured for the external quantum efficiency of the quantum dots (external quantum efficiency after heat treatment), and the results are shown in Table 3.

[0237] (Table 3)

[0238] (Unit: %)

[0239]

[0240] Referring to Table 3, the solvent-free curable composition of Example 1 and the solvent-free curable composition of Comparative Example 1 both minimized the deterioration of the quantum efficiency of the quantum dots.

[0241] Evaluation 3: Evaluation of storage stability (40°C)

[0242] To evaluate the storage stability of the solvent-free curable compositions according to Examples 1 to 5 and Comparative Example 1, the initial viscosity and the viscosity after 14 days (temperature conditions were constantly maintained) of the compositions were measured with a viscometer (RV-2 spindle, 23 rpm, DV-II, Brookfield Engineering Laboratories, Inc.) at 40°C, respectively, and then each viscosity difference between the initial viscosity and the viscosity after 14 days was shown in Table 4.

[0243] (Table 4)

[0244] (Unit: centipoise)

[0245] Example 1 Example 2 Example 3 Example 4 Example 5 Comparative example 1 Viscosity difference 0.2 0.4 0.4 0.3 0.1 2.6

[0246] Referring to Table 4, the solvent-free curable compositions according to the examples exhibited excellent storage stability compared to the solvent-free curable composition according to Comparative Example 1.

[0247] Evaluation 4: Evaluation of inkjet properties by dwell time

[0248] To evaluate the inkjet properties of the solvent-free curable compositions according to Examples 1 to 5 and Comparative Example 1, each composition was inkjetted and a photograph was taken, and the results are shown in Figures 1 to 8 .

[0249] Referring to Figures 1 to 8 , the solvent-free curable compositions according to the examples maintained the ejection properties even with a long dwell time, but the solvent-free curable composition according to Comparative Example 1 exhibited deteriorated ejection properties although with a short dwell time.

[0250] While the application has been described in connection with what is presently considered to be the practical example embodiments, it is to be understood that the application is not limited to the disclosed embodiments, but, on the contrary, is intended to cover various modifications and equivalent arrangements included within the spirit and scope of the appended claims. Therefore, the foregoing examples should be understood not to be limiting the application, but rather are presented as example embodiments.

Claims

1. A solvent-free curable composition, comprising: quantum dots; as well as Curable monomers represented by any of chemical formulas 3 to 6: [Chemical Formula 3] [Chemical Formula 4] [Chemical Formula 5] [Chemical Formula 6] 2. The solvent-free curable composition according to claim 1, wherein the curable monomer represented by any one of chemical formulas 3 to 6 has a content of 1.0 × 10⁻⁶. -4 Up to 5.0×10 -2 The vapor pressure of Torr.

3. The solvent-free curable composition according to claim 2, wherein the curable monomer represented by any one of chemical formulas 3 to 6 has a viscosity of 4 centipoise to 10 centipoise.

4. The solvent-free curable composition according to claim 1, wherein the solvent-free curable composition has a viscosity of 20 centipoise to 40 centipoise.

5. The solvent-free curable composition according to claim 1, wherein the quantum dots have a maximum fluorescence emission wavelength in the range of 500 nm to 680 nm.

6. The solvent-free curable composition according to claim 1, wherein... Based on the total amount of the solvent-free curable components, The solvent-free curable composition includes: 5% to 60% by weight of the quantum dots; as well as From 40% to 95% by weight of the curable monomer represented by any one of chemical formulas 3 to 6.

7. The solvent-free curable composition according to claim 1, wherein the solvent-free curable composition further comprises a polymerization initiator, a light diffuser, or a combination thereof.

8. The solvent-free curable composition according to claim 7, wherein the light diffuser comprises barium sulfate, calcium carbonate, titanium dioxide, zirconium oxide, or a combination thereof.

9. The solvent-free curable composition according to claim 1, wherein the solvent-free curable composition further comprises polymerization inhibitor, malonic acid, 3-amino-1,2-propanediol, silane coupling agent, leveling agent, fluorinated surfactant, or a combination thereof.

10. A cured layer, manufactured using a solvent-free curable composition as described in any one of claims 1 to 9.

11. A color filter comprising the cured layer as described in claim 10.

12. A display device comprising the color filter as claimed in claim 11.

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