Light-converting ink composition, light-converting laminated substrate manufactured using the same, light-converting pixel substrate, and image display device

Abstract

The present invention relates to a light-converting ink composition comprising light-emitting particles, polymerizable monomers, and an additive having a specific structure, a light-converting layered substrate, a light-converting pixel substrate, and an image display device manufactured using the same, which has improved light-conversion efficiency, has little change in absorbance of blue light and droplet size even when stored at room temperature, and also has excellent light resistance, heat resistance, high-temperature high-humidity stability, viscosity stability, particle size change stability, does not generate foreign matter on the surface, and has excellent inkjet ejection performance and improved nozzle wettability.

Description

Technical Field

[0001] This invention relates to light conversion ink compositions, light conversion laminates manufactured using the same, light conversion pixel substrates, and image display devices. Background Technology

[0002] With the development of the information society, the requirements for display devices used to display images have increased in various forms. Recently, various display devices such as liquid crystal display (LCD), plasma display panel (PDP), and organic light-emitting diode display (OLED) have been used.

[0003] Color gamut is one of the most important elements in display devices. Recently, as an example of a solution to improve the color gamut of a display device, a display with a light conversion stacked substrate that utilizes blue LEDs instead of conventional white LEDs and includes quantum dots as a separate light conversion means has begun to be used. For example, by applying a light conversion stacked substrate or a light conversion pixel substrate including a light conversion layer with dispersed quantum dots to a backlight unit using blue LED chips or a color filter including pixels, the light conversion efficiency is improved, thereby enhancing the color reproduction of the display device.

[0004] Furthermore, to manufacture color filters that utilize light-converting pixels, photolithography can be employed using compositions containing luminescent particles such as quantum dots. However, while this method excels in the refinement and reproducibility of color filters, forming pixels requires coating, exposure, development, and curing processes for each color. This increases manufacturing steps, time, and costs, and leads to more control factors between processes, making yield management difficult.

[0005] To address these issues, inkjet printing was developed. Inkjet printing is a technique that uses an inkjet head to spray liquid ink onto pre-defined, designated areas to create images colored with various inks. It can color multiple colors, including red, green, and blue, at once, thus significantly reducing manufacturing steps, time, and costs.

[0006] Relatedly, Korean Patent No. 10-1475520 discloses a quantum dot ink composition for inkjet printing, and Korean Patent No. 10-1628065 discloses a composition containing a luminescent complex. However, both suffer from insufficient light conversion efficiency, particularly significant variations in blue light absorbance and droplet size over time. Furthermore, the aforementioned technologies exhibit large particle size variation rates, leading to surface foreign matter buildup, and also present issues with lightfastness, heat resistance, and high-temperature and high-humidity stability. Moreover, coatings prepared from quantum dot-containing light conversion ink compositions not only suffer from poor light conversion efficiency, color purity, coating uniformity, and inkjet ejection performance, but also suffer from deteriorated optical properties due to the aggregation of scattering particles and nozzle wetting issues caused by the ink composition.

[0007] Therefore, there is a need to develop a light conversion ink composition that enables the formation of light conversion multilayer substrates and light conversion pixel substrates with excellent light conversion efficiency, minimal changes in blue light absorbance and droplet size, minimal particle size change over time, and improved lightfastness, heat resistance, high-temperature and high-humidity stability, viscosity stability over time, and surface foreign matter characteristics. Furthermore, there is a need to develop a light conversion ink composition that can form light conversion multilayer substrates and light conversion pixel substrates with excellent light conversion efficiency, color purity, and coating uniformity, without agglomeration of scattering particles, excellent inkjet ejection performance, and prevention of nozzle wetting.

[0008] [Existing technical documents]

[0009] [Patent Literature]

[0010] (Patent Document 1) Korean Patent No. 10-1475520

[0011] (Patent Document 2) Korean Patent No. 10-1628065 Summary of the Invention

[0012] Technical issues

[0013] One object of the present invention is to provide a light conversion ink composition that has improved light conversion efficiency and exhibits minimal changes in blue light absorbance and droplet size even when stored at room temperature.

[0014] One object of the present invention is to provide a light conversion ink composition that has excellent light conversion properties and continuous inkjet process.

[0015] One objective of this invention is to provide a light conversion ink composition with excellent lightfastness, heat resistance, high temperature and high humidity stability, and viscosity stability.

[0016] In addition, an object of the present invention is to provide a light conversion ink composition with excellent color purity and coating uniformity and reduced agglomeration of scattering particles.

[0017] One object of the present invention is to provide a light conversion ink composition that has excellent light conversion properties and continuous inkjet process.

[0018] In addition, an object of the present invention is to provide a light conversion laminate substrate, a light conversion pixel substrate, and an image display device manufactured using the light conversion ink composition.

[0019] Technical solution

[0020] To solve the above-mentioned technical problems, the present invention provides a light conversion ink composition comprising light-emitting particles, polymerizable monomers, and additives having a specific structure.

[0021] Furthermore, the present invention provides a light conversion laminate substrate, a light conversion pixel substrate, and an image display device manufactured using the above-described light conversion ink composition.

[0022] Invention Effects

[0023] By using the light conversion ink composition according to the present invention, it is possible to provide a light conversion coating with improved light conversion efficiency and minimal changes in blue light absorbance and droplet size even when stored at room temperature.

[0024] Furthermore, by using the light conversion ink composition according to the present invention, not only can high light conversion efficiency be achieved to obtain excellent brightness, but also a very small particle size change rate can be obtained, and the viscosity stability over time and foreign matter properties can be improved. Therefore, excellent light conversion coatings without blemishes can be provided in continuous processes.

[0025] By using the light conversion ink composition according to the present invention, a light conversion coating film with excellent light resistance, heat resistance, high temperature and high humidity stability, and viscosity stability can be provided.

[0026] Furthermore, the light conversion ink composition according to the present invention can improve the color purity and uniformity of the coating film and reduce the aggregation of scattering particles compared with existing light conversion ink compositions.

[0027] By using the light conversion ink composition according to the present invention, not only can high light conversion efficiency be achieved to obtain excellent brightness, but inkjet ejection performance and nozzle wettability can also be improved. Therefore, an excellent light conversion ink composition that prevents spot formation in continuous processes can be provided.

[0028] The present invention enables the effective application of the above-described light conversion ink composition to backlight units or light conversion pixel substrates and image display devices. Detailed Implementation

[0029] The present invention provides a light conversion ink composition and a light conversion laminate substrate, a light conversion pixel substrate and an image display device made therefrom, wherein the ink composition comprises light-emitting particles and polymerizable monomers, the light-emitting particles comprising a core and a shell containing a specific metal element, and the ink composition comprises at least one compound selected from chemical formula 1 and chemical formulas 6 to 9, thereby improving light conversion efficiency and making the changes in absorbance of blue light and droplet size very small.

[0030] Furthermore, the present invention provides a light conversion ink composition and a light conversion laminate substrate and a light conversion pixel substrate manufactured using the same, wherein the light conversion ink composition has excellent light conversion efficiency and jetting characteristics based on the above composition, its particle size and viscosity change very little over time, and it prevents foreign matter from appearing on the coating film.

[0031] In addition, the present invention is characterized by its ability to improve the absorption of blue light sources, thereby improving light conversion efficiency, as well as light resistance, heat resistance, high temperature and high humidity stability and viscosity stability.

[0032] Furthermore, the present invention provides a light conversion ink composition and a light conversion laminate substrate and a light conversion pixel substrate manufactured using the same, wherein the light conversion ink composition, based on the above composition, has excellent light conversion efficiency, color purity and coating uniformity and reduces the aggregation of scattering particles.

[0033] The present invention provides a light conversion ink composition and a light conversion laminate substrate and a light conversion pixel substrate manufactured using the same, wherein the light conversion ink composition has high light efficiency, low full width at half maximum (FWHM), improved inkjet ejection performance and nozzle wettability, and excellent color purity based on the above composition.

[0034] Image display devices, including backlight units and / or light-converting pixel substrates manufactured using the light-converting ink composition of the present invention, have excellent color purity due to the full width at half maximum (FWHM) of the light they convert and emit being less than 40 nm. Therefore, they have the following advantages: they can not only ensure color reproducibility of more than 100% based on the NTSC color gamut, but also have excellent light conversion efficiency.

[0035] The present invention will now be described in detail.

[0036] <Photoconversion ink composition>

[0037] The light-converting ink composition of the present invention comprises luminescent particles and polymerizable monomers, and contains at least one compound selected from chemical formulas 1 and 6 to 9, and may also contain at least one compound represented by chemical formula 11, scattering particles, photopolymerization initiator, additives and solvents.

[0038] luminescent particles

[0039] Luminescent particles, for example, can emit light with a wavelength different from the absorbed wavelength by absorbing light of a specified wavelength. The luminescent nanocrystal particles can be red luminescent particles emitting light (red light) with a peak emission wavelength in the range of 605 to 665 nm, green luminescent particles emitting light (green light) with a peak emission wavelength in the range of 500 to 600 nm, or blue luminescent particles emitting light (blue light) with a peak emission wavelength in the range of 420 to 480 nm. The light-converting ink composition of the present invention preferably contains at least one of the above-mentioned luminescent particles.

[0040] In this invention, the light-emitting particles include semiconductor materials, such as quantum dots.

[0041] According to one embodiment of the present invention, the luminescent particles may have a ligand layer on their surface.

[0042] In one embodiment of the invention, the quantum dot has a core-shell structure, including a core and a shell covering at least a portion of the core.

[0043] In this invention, the core-shell structure can be a structure consisting of a core and a first shell, such as a core / shell structure, or a structure consisting of a core, a first shell, and a second shell, i.e., a core / shell / shell structure.

[0044] The core comprises a quaternary compound containing silver (Ag), indium (In), gallium (Ga), and sulfur (S). For example, the core is AgInGaS. Such a core has the advantage of more effectively absorbing short-wavelength light sources and minimizing the light absorption rate in the emitting region, thus excellent light conversion efficiency can be expected even with low content.

[0045] The shell contains at least two elements selected from In, Ga, and S, and may contain, for example, GaS. In this case, in the present invention, the shell can maintain a narrow full width at half maximum (FWHM) of the emission wavelength by suppressing trap emission of the nucleus, thereby improving color purity.

[0046] According to an exemplary embodiment, examples of core-shell structured quantum dots may include, but are not limited to, AgInGaS / GaS, etc.

[0047] In some embodiments, if desired, the present invention may also include quantum dots with structures other than the core-shell structure described above. For example, it may also include core-shell quantum dots such as InP / ZnSe / ZnS, InP / ZnS, InGaP / ZnS, and InGaP / ZnSe / ZnS, but is not limited thereto.

[0048] Quantum dots can be synthesized using wet chemical processes, metal-organic chemical vapor deposition (MOCVD), or molecular beam epitaxy (MBE), but are not limited to these methods. Preferably, synthesis is performed using wet chemical processes, as this yields quantum dots with superior optical properties.

[0049] Wet chemistry is a method of growing particles by placing precursor materials in an organic solvent. During crystal growth, the organic solvent naturally coordinates on the surface of the quantum dot crystal to act as a dispersant, thereby controlling the crystal growth. Therefore, wet chemistry is preferred for preparing quantum dots because it allows for easier and lower-cost control of nanoparticle growth compared to vapor deposition methods such as organometallic chemical vapor deposition or molecular beam epitaxy.

[0050] In this invention, based on 100% by weight of the solid content in the light-conversion ink composition, the content of luminescent particles can be from 3% to 50% by weight, preferably from 5% to 45% by weight, and more preferably from 8% to 40% by weight. When the content of luminescent particles is within the above range, the light conversion efficiency can be improved.

[0051] When the content of luminescent particles is below the above range, the light conversion efficiency will decrease, making it difficult to achieve a high-quality display device. Furthermore, if the content exceeds the above range, it will result in a lack of components necessary for curing, leading to insufficient coating curing, which may reduce the productivity of subsequent processes in display manufacturing and the reliability of the product.

[0052] polymerizable monomers

[0053] In one embodiment of the present invention, the light conversion ink composition comprises a polymerizable monomer.

[0054] Polymerizable monomers may contain compounds represented by the following chemical formula 10.

[0055] [Chemical Formula 10]

[0056]

[0057] In chemical formula 10,

[0058] R 281 It is an alkylene, phenylene, or cycloalkylene having 1 to 20 carbon atoms;

[0059] R 291 Each is independently hydrogen or an alkyl group having 1 to 20 carbon atoms, preferably hydrogen or methyl;

[0060] m 10 It is an integer from 1 to 15.

[0061] The term "alkylene" as used in this specification refers to straight-chain or branched divalent hydrocarbons having 1 to 20 carbon atoms, such as methylene, ethylene, n-propylene, isopropylene, n-butylene, isobutylene, n-pentylene, n-hexylene, n-heptylene, n-octylene, n-nonylene, etc., but not limited to these.

[0062] The term "cycloalkylene" as used in this specification refers to monocyclic or fused-ring divalent hydrocarbons having 3 to 10 carbon atoms, such as cyclopropylene, cyclobutylene, cyclopentylene, and cyclohexylene, but not limited thereto.

[0063] One or more hydrogen atoms in alkylene, phenylene, and cycloalkylene with 3 to 10 carbon atoms can be derived from C1-C6 alkyl, C2-C6 alkenyl, C2-C6 ynyl, or C3-C 10 cycloalkyl, C3-C 10 Heterocyclic alkyl, C3-C 10 Substitutions include heterocyclic alkoxy, C1-C6 haloalkyl, C1-C6 alkoxy, C1-C6 thioalkoxy, aryl, acyl, hydroxyl, thio, halogen, amino, alkoxycarbonyl, carboxyl, carbamoyl, cyano, nitro, etc.

[0064] In one embodiment of the present invention, R 281 It can be C1-C 20 Alkylene, preferably C2-C 16 Alkylene. When R 281 For C1-C 20 When alkylene oxides are used, the light-conversion ink composition of the present invention exhibits excellent dispersion of luminescent particles even in the absence of solvents, thereby improving spraying performance and enhancing coating hardness and thickness uniformity.

[0065] According to an embodiment of the present invention, m 10 It can be an integer from 1 to 15 as described above, preferably an integer from 1 to 5. If it exceeds the above range, it will result in higher viscosity, which may lead to deterioration of dispersibility.

[0066] Specific examples of compounds represented by Formula 10 may include, but are not limited to, 1,6-hexanediol diacrylate, polyethylene glycol diacrylate, 2-hydroxy-3-methacrylpropylacrylate, 1,9-bisacryloxynonane, tripropylene glycol diacrylate, etc.

[0067] The compound represented by Chemical Formula 10 improves the dispersibility of luminescent particles, thereby enabling the achievement of low-viscosity light-conversion ink compositions of 80 cP or lower without solvents. Therefore, the light-conversion ink compositions of the present invention can be effectively used to manufacture light-conversion laminates using inkjet printing.

[0068] In addition to the polymerizable monomer represented by Formula 10, the photoconversion ink compositions of the present invention may also contain polymerizable compounds commonly used in the art, without departing from the purpose of the invention. Examples may include monofunctional monomers, difunctional monomers, and other multifunctional monomers, with difunctional monomers being preferred.

[0069] There are no particular restrictions on the types of monofunctional monomers, and examples may include nonylphenyl carbitol acrylate, 2-hydroxy-3-phenoxypropyl acrylate, 2-ethylhexyl carbitol acrylate, 2-hydroxyethyl acrylate, N-vinylpyrrolidone, etc.

[0070] There are no particular restrictions on the types of bifunctional monomers; examples may include bis(acryloyloxyethyl) ether of bisphenol A.

[0071] There are no particular restrictions on the types of multifunctional monomers, and examples may include trimethylolpropane tri(meth)acrylate, ethoxylated trimethylolpropane tri(meth)acrylate, propoxylated trimethylolpropane tri(meth)acrylate, pentaerythritol tri(meth)acrylate, pentaerythritol tetra(meth)acrylate, dipentaerythritol tri(meth)acrylate, dipentaerythritol penta(meth)acrylate, ethoxylated dipentaerythritol hexa(meth)acrylate, propoxylated dipentaerythritol hexa(meth)acrylate, dipentaerythritol hexa(meth)acrylate, etc.

[0072] In this case, when further containing trifunctional or more functional multifunctional curable monomers, inkjet characteristics can be obtained if the viscosity of the ink composition is controlled to be below 80 cP.

[0073] Based on 100% by weight of the total solids content of the light-conversion ink composition, the content of polymerizable monomers can be 30 to 95% by weight, preferably 40 to 90% by weight. When the content of polymerizable monomers is within the above range, it has a preferred advantage in terms of pixel unit strength or smoothness. When the content of polymerizable monomers is below the above range, it is difficult to ensure the flowability for inkjet printing, while when the content exceeds the above range, it will result in insufficient content of light-emitting particles, which may cause a decrease in light efficiency. Therefore, the content is preferably within the above range.

[0074] Compounds of chemical formula 1 and chemical formulas 6 through 9

[0075] The present invention is characterized by comprising at least one of the compounds represented by the following chemical formulas 1 and 6 to 9, such that quantum dots can be stably dispersed in the ink composition, thereby having the effect of helping to prevent nozzle clogging even between inkjet processes.

[0076] [Chemical Formula 1]

[0077]

[0078] In chemical formula 1,

[0079] R a R b and R c Each is independently hydrogen, a substituted or unsubstituted alkyl group having 1 to 5 carbon atoms, or a hydrocarbon group having 2 to 50 carbon atoms containing at least one nitrogen atom (preferably containing at least two nitrogen atoms).

[0080] In this invention, the substituents used for "substitution" are hydroxyl, amino, alkyl having 1 to 10 carbon atoms, alkenyl having 1 to 10 carbon atoms, alkynyl having 1 to 10 carbon atoms, amino having 1 to 10 carbon atoms, ethoxy and / or halogen groups having 1 to 10 carbon atoms, wherein alkyl, alkenyl, alkynyl, amino and ethoxy include all straight-chain, branched, linear and cyclic groups, and include groups substituted or unsubstituted by at least one hydroxyl, halogen group, amino, etc.

[0081] Specifically, the compounds represented by chemical formula 1 of the present invention may include at least one of the compounds having the structures of chemical formulas 2 to 5.

[0082] [Chemical Formula 2]

[0083]

[0084] In chemical formula 2,

[0085] R1, R2, R4, R6 and R7 are each independently hydrogen, or substituted or unsubstituted alkyl groups having 1 to 5 carbon atoms;

[0086] R3 and R5 are each independently substituted or unsubstituted alkylene groups having 1 to 5 carbon atoms.

[0087] [Chemical Formula 3]

[0088]

[0089] In chemical formula 3,

[0090] R8, R9, R 11 R 13 R 15 and R 16 Each is independently hydrogen, or a substituted or unsubstituted alkyl group having 1 to 5 carbon atoms;

[0091] R 10 R 12 and R 14 Each is independently a substituted or unsubstituted alkylene group having 1 to 5 carbon atoms.

[0092] [Chemical Formula 4]

[0093]

[0094] In chemical formula 4,

[0095] R 17 R 18 R 21 R 22 R 24 and R 25 Each is independently hydrogen, or a substituted or unsubstituted alkyl group having 1 to 5 carbon atoms;

[0096] R 19 R 20 and R 23 Each is independently a substituted or unsubstituted alkylene group having 1 to 5 carbon atoms.

[0097] [Chemical Formula 5]

[0098]

[0099] In chemical formula 5,

[0100] R 17 R 18 R 20 R 22 R 24 R 26 and R 27Each is independently hydrogen, or a substituted or unsubstituted alkyl group having 1 to 5 carbon atoms;

[0101] R 19 R 21 R 23 and R 25 Each is independently a substituted or unsubstituted alkylene group having 1 to 5 carbon atoms.

[0102] [Chemical Formula 6]

[0103]

[0104] In chemical formula 6,

[0105] R 61 and R 62 Each of the following can be independently substituted or unsubstituted alkylene with 1 to 10 carbon atoms, substituted or unsubstituted cycloalkylene with 5 to 10 carbon atoms, substituted or unsubstituted arylene with 4 to 20 carbon atoms, substituted or unsubstituted heteroarylene with 4 to 20 carbon atoms, substituted or unsubstituted arylalkylene with 6 to 30 carbon atoms, or substituted or unsubstituted heteroarylalkylene with 6 to 30 carbon atoms;

[0106] R 63 It can be a substituted or unsubstituted alkylene group having 1 to 10 carbon atoms, a substituted or unsubstituted alkenyl group having 1 to 10 carbon atoms, a substituted or unsubstituted cycloalkylene group having 5 to 10 carbon atoms, a substituted or unsubstituted alkyleneoxy group having 1 to 10 carbon atoms, or a substituted or unsubstituted alkylthiol group having 1 to 10 carbon atoms.

[0107] R 64 and R 65 Each can be hydrogen, or a substituted or unsubstituted alkyl group having 1 to 10 carbon atoms;

[0108] X6 and Y6 can each be hydrogen or hydroxyl groups independently.

[0109] Alkyl, alkylene, cycloalkylene, aryl, heteroaryl, arylalkylene, and heteroarylalkylene may have one or more substituents, which may be alkyl having 1 to 6 carbon atoms, fluoroalkyl having 1 to 6 carbon atoms, perfluoroalkyl having 1 to 6 carbon atoms, fluoroalkoxy having 1 to 6 carbon atoms, perfluoroalkoxy having 1 to 6 carbon atoms, alkenyl having 2 to 6 carbon atoms, alkynyl having 2 to 6 carbon atoms, cycloalkyl having 3 to 10 carbon atoms, heterocycloalkyl having 3 to 10 carbon atoms, heterocycloalkoxy having 3 to 10 carbon atoms, haloalkyl having 1 to 6 carbon atoms, alkoxy having 1 to 6 carbon atoms, thioalkoxy having 1 to 6 carbon atoms, aryl, acyl, hydroxyl, thiol, halogen, amino, aminoalkyl, alkoxycarbonyl, carboxyl, carbamoyl, cyano, nitro, etc., but not limited to these.

[0110] In order to minimize the changes in viscosity and particle size of the light conversion ink composition over time, suppress the appearance of foreign matter on the surface of the coating film formed by the light conversion ink composition, and improve the light conversion efficiency, the light conversion ink composition of the present invention preferably contains an amine compound of chemical formula 6.

[0111] [Chemical Formula 7]

[0112]

[0113] In chemical formula 7,

[0114] R 71 Aryl groups, with or without substituted carbon atoms, having 6 to 20 carbon atoms;

[0115] R 72 For substituted or unsubstituted aryl groups having 6 to 20 carbon atoms

[0116] R 73 A substituted or unsubstituted aryl group having 6 to 20 carbon atoms;

[0117] R 74 It is a substituted or unsubstituted aryl or alkyl group having 6 to 20 carbon atoms.

[0118] In this invention, the substituents used for "substitution" are hydroxyl, amino, alkyl having 1 to 10 carbon atoms, alkenyl having 1 to 10 carbon atoms, alkynyl having 1 to 10 carbon atoms, amino having 1 to 10 carbon atoms, ethoxy and / or halogen groups having 1 to 10 carbon atoms, wherein alkyl, alkenyl, alkynyl, amino and ethoxy include all straight-chain, branched, linear and cyclic groups, and include groups substituted or unsubstituted by at least one hydroxyl, halogen group, amino, etc.

[0119] This invention contains a compound represented by chemical formula 7, which has the effect of protecting quantum dots, thereby enabling stable light efficiency during the manufacturing process and reliability evaluation.

[0120] [Chemical Formula 8]

[0121]

[0122] In chemical formula 8,

[0123] R 81 and R 82 Each can be independently a hydrogen atom or a methyl group;

[0124] R 83 R 84 and R 85 Each of the following is independently a direct bond: substituted or unsubstituted alkylene group having 1 to 20 carbon atoms; substituted or unsubstituted cycloalkylene group having 3 to 10 carbon atoms; substituted or unsubstituted arylene group having 5 to 20 carbon atoms; substituted or unsubstituted heteroarylene group having 2 to 15 carbon atoms; substituted or unsubstituted arylalkylene group having 6 to 30 carbon atoms; substituted or unsubstituted heteroarylalkylene group having 3 to 30 carbon atoms; substituted or unsubstituted alkenylene group having 2 to 10 carbon atoms; substituted or unsubstituted alkyneylene group having 2 to 10 carbon atoms; substituted or unsubstituted alkoxyalkylene group having 1 to 10 carbon atoms; substituted or unsubstituted dialkoxyalkylene group having 1 to 10 carbon atoms; -(CH2O)-; -(CH2CH2O)-; or -(CH2CH(CH3)O) l8 -;

[0125] X8 is a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted cycloalkyl group having 3 to 10 carbon atoms, a substituted or unsubstituted aryl group having 5 to 20 carbon atoms, a substituted or unsubstituted heteroaryl group having 2 to 15 carbon atoms, a substituted or unsubstituted alkenyl group having 2 to 10 carbon atoms, a substituted or unsubstituted alkynyl group having 2 to 10 carbon atoms, or a substituted or unsubstituted alkoxy, hydroxyl, amino, thiol, or carboxyl group having 1 to 5 carbon atoms.

[0126] Y8 is a direct bond, ester group, or amide group;

[0127] l8 and n8 are integers from 1 to 20.

[0128] Alkyl or alkylene compounds having 1 to 20 carbon atoms refer to straight-chain or branched monovalent or divalent hydrocarbons having 1 to 20 carbon atoms. Examples include, but are not limited to, methyl (methyl)yl, ethyl (ethyl)yl, n-propyl (propyl)yl, isopropyl (propyl)yl, n-butyl (butyl)yl, isobutyl (butyl)yl, n-pentyl (pentyl)yl, n-hexyl (hexyl)yl, n-octyl (octyl)yl, and n-nonyl (nonyl)yl.

[0129] Cycloalkyl or cycloalkylene hydrocarbons having 3 to 10 carbon atoms refer to monocyclic or fused-ring monovalent or divalent hydrocarbons having 3 to 10 carbon atoms. Examples include, but are not limited to, cyclopropyl (propylene), cyclobutyl (butylene), cyclopentyl (pentylene), and cyclohexyl (hexylene).

[0130] Aryl or arylene compounds having 5 to 20 carbon atoms refer to monocyclic or polycyclic monovalent or divalent aromatic hydrocarbons derived from aromatic hydrocarbons having 5 to 20 carbon atoms. Examples include, but are not limited to, phenylene(phenylene), biphenylene(phenylene), terphenylene(phenylene), and naphthyl(naphthylene).

[0131] A heteroaryl or heteroarylene group having 2 to 15 carbon atoms refers to a group having 2 to 15 carbon atoms in which at least one carbon atom (C) is replaced by a heteroatom such as an oxygen atom (O), a nitrogen atom (N), or a sulfur atom (S). Examples include thiopheneyl, furanyl, pyrrolyl, imidazolyl, thiazolyl, oxazolyl, oxadiazolyl, pyridyl, bipyridyl, pyrimidinyl, triazinyl, triazolyl, acridineyl, pyrazinyl, quinolinyl, quinazolinyl, quinoxolinyl, phthalazinyl, pyridopyrimidinyl, pyridopyrazinyl, isoquinolinyl, indolyl, carbazoleyl, benzoxazolyl, benzimidazolyl, benzothiazolyl, benzocarbazoleyl, benzothiopheneyl, dibenzothiopheneyl, benzofuranyl, and phenanthrolinel. (enanthroline), thiazolyl, isoxazolyl, oxadiazolyl, thiadiazolyl, benzothiazolyl, phenothiazinyl, aziridinyl, azidinoyl, isoindolyl, indazole, purine, pteridine, β-carbonyl, naphthyridine, terpyridinyl, pherazinyl, imidazopyridinyl, pyrrolopyridinyl, acrylonitrile, pyrazolyl, dibenzofuranyl or their divalent functional groups, but not limited thereto.

[0132] An arylalkylene group having 6 to 30 carbon atoms refers to a group having 6 to 30 carbon atoms in which at least one hydrogen atom (H) of the aryl group is replaced by a lower alkylene group (e.g., methylene, ethylene, propylene, etc.). Examples include, but are not limited to, benzylene, phenylethylene, etc.

[0133] A heteroarylene alkylene with 3 to 30 carbon atoms refers to an arylene alkylene with 3 to 30 carbon atoms in which at least one carbon atom (C) is replaced by a heteroatom such as an oxygen atom (O), a nitrogen atom (N), or a sulfur atom (S).

[0134] Alkenyl or alkenyl groups having 2 to 10 carbon atoms refer to straight-chain, branched, or cyclic monovalent or divalent hydrocarbons derived from olefins having 2 to 10 carbon atoms.

[0135] Alkynyl or ynynyl groups with 2 to 10 carbon atoms refer to straight-chain, branched, or cyclic monovalent or divalent hydrocarbons derived from alkynes with 2 to 10 carbon atoms.

[0136] Alkoxyalkylene compounds having 1 to 10 carbon atoms refer to straight-chain or branched divalent hydrocarbons having 1 to 10 carbon atoms and containing 1 alkoxy group. Examples include, but are not limited to, methoxymethylene, ethoxymethylene, ethoxyethylene, methoxypropylene, and methoxybutylene.

[0137] Dialkoxyalkylene refers to a straight-chain or branched divalent hydrocarbon having 1 to 10 carbon atoms and containing two alkoxy groups. Examples include, but are not limited to, dimethoxymethylene, diethoxymethylene, diethoxyethylene, dimethoxypropylene, and dimethoxybutylene.

[0138] Alkyl, alkylene, cycloalkyl, cycloalkylene, aryl, arylene, heteroaryl, heteroarylene, arylalkylene, heteroarylalkylene, alkenyl, alkenylene, ynyl, ynylene may have one or more substituents, wherein the substituents may be alkyl having 1 to 6 carbon atoms, alkenyl having 2 to 6 carbon atoms, ynyl having 2 to 6 carbon atoms, cycloalkyl having 3 to 10 carbon atoms, heterocycloalkyl having 3 to 10 carbon atoms, heterocycloalkoxy having 3 to 10 carbon atoms, haloalkyl having 1 to 6 carbon atoms, alkoxy having 1 to 6 carbon atoms, thioalkoxy having 1 to 6 carbon atoms, aryl, acyl, hydroxyl, thiol, halogen, amino, alkoxycarbonyl, carboxyl, carbamoyl, cyano, nitro, etc., but not limited to these.

[0139] [Chemical Formula 9]

[0140]

[0141] In chemical formula 9, R 91 and R 92Each of the following is independently a single bond, an alkoxyalkylene group having 1 to 10 carbon atoms, a divalent or trivalent amino group having 1 to 10 carbon atoms, an arylene group having 1 to 10 carbon atoms, or a substituted or unsubstituted alkylene group having 1 to 10 carbon atoms, wherein A9 is a substituted or unsubstituted aryl group having 5 to 20 carbon atoms, a substituted or unsubstituted arylene group having 5 to 20 carbon atoms, a substituted or unsubstituted heteroaryl group having 5 to 20 carbon atoms, a substituted or unsubstituted heteroarylene group having 5 to 20 carbon atoms, or a substituted or unsubstituted heterocyclic alkylene group having 4 to 20 carbon atoms, and n9 may be 0 to 1.

[0142] Alkoxyalkylene, alkylene, heterocyclic alkylene, aryl, arylene, heteroaryl, and heteroarylene may have one or more substituents, wherein the substituents may be alkyl having 1 to 6 carbon atoms, fluoroalkyl having 1 to 6 carbon atoms, perfluoroalkyl having 1 to 6 carbon atoms, fluoroalkoxy having 1 to 6 carbon atoms, perfluoroalkoxy having 1 to 6 carbon atoms, alkenyl having 2 to 6 carbon atoms, alkynyl having 2 to 6 carbon atoms, or having 3 to 1 carbon atom. Cycloalkyl groups with 0 carbon atoms, heterocycloalkyl groups with 3 to 10 carbon atoms, heterocycloalkoxy groups with 3 to 10 carbon atoms, haloalkyl groups with 1 to 6 carbon atoms, alkoxy groups with 1 to 6 carbon atoms, thioalkoxy groups with 1 to 6 carbon atoms, aryl, acyl, hydroxyl, thiol, halogen-substituted alkoxy groups, halogen groups, amino, aminoalkyl, amino-substituted alkoxy, alkoxycarbonyl, carboxyl, carbamoyl, cyano, nitro, etc., but not limited to these.

[0143] The light conversion ink composition of the present invention, by comprising a compound represented by chemical formula 9, can improve light conversion performance, color purity and inkjet output performance, and improve nozzle wettability.

[0144] Preferably, the compounds represented by chemical formula 1 of the present invention may include at least one compound having the following structure, but are not limited thereto.

[0145] [Chemical Formula 2-1]

[0146]

[0147] Diethylenetriamine, TCI Corporation

[0148] [Chemical Formula 2-2]

[0149]

[0150] 2,2'-Diamino-N-methyldiethylamine, TCI Corporation

[0151] [Chemical Formula 2-3]

[0152]

[0153] N,N',N”-Trimethyldiethylenetriamine, TCI Corporation [Chemical Formula 2-4]

[0154]

[0155] N,N,N',N”,N”-Pentamethyldiethylenetriamine, TCI Corporation [Chemical Formula 2-5]

[0156]

[0157] 3,3'-Diaminodipropylamine, TCI Corporation

[0158] [Chemical Formula 2-6]

[0159]

[0160] 3,3'-Iminebis(N,N-dimethylpropylamine), TCI Corporation [Chemical Formula 2-7]

[0161]

[0162] 2,6,10-Trimethyl-2,6,10-triazaundecane, TCI [Chemical Formula 2-8]

[0163]

[0164] N,N,N”,N”-Tetrabutyldiethylenetriamine, TCI Corporation

[0165] [Chemical Formula 2-9]

[0166]

[0167] N,N,N”,N”-Tetraisopropyldiethylenetriamine, TCI Corporation [Chemical Formula 2-10]

[0168]

[0169] N,N,N',N”,N”-Penta(2-hydroxypropyl)diethylenetriamine, TCI Corporation [Chemical Formula 3-1]

[0170]

[0171] TCI Corporation, a company specializing in triethylenetetramine

[0172] [Chemical Formula 3-2]

[0173]

[0174] 1,1,4,7,10,10-Hexamethyltriethylenetetramine, TCI Corporation [Chemical Formula 3-3]

[0175]

[0176] N,N'-Bis(3-aminopropyl)ethylenediamine, TCI Corporation

[0177] [Chemical Formula 3-1]

[0178]

[0179] Tris(2-aminoethyl)amine, TCI Corporation

[0180] [Chemical Formula 3-2]

[0181]

[0182] Tris[2-(dimethylamino)ethyl]amine, TCI Corporation

[0183] [Chemical Formula 3-3]

[0184]

[0185] Tris(3-aminopropyl)amine, TCI Corporation

[0186] [Chemical Formula 5-1]

[0187]

[0188] Tetraethylenepentamine, Sigma Aldrich

[0189] The compound represented by chemical formula 6 is not particularly limited as long as it can minimize the changes in viscosity and particle size of the light conversion ink composition over time, suppress the generation of foreign matter on the surface of the coating film formed by the light conversion ink composition, and improve the light conversion efficiency, but more preferably includes at least one compound represented by the following chemical formulas 6-1 to 6-22.

[0190] [Chemical Formula 6-1]

[0191]

[0192] [Chemical Formula 6-2]

[0193]

[0194] [Chemical Formula 6-3]

[0195]

[0196] [Chemical Formula 6-4]

[0197]

[0198] [Chemical Formula 6-5]

[0199]

[0200] [Chemical Formula 6-6]

[0201]

[0202] [Chemical Formulas 6-7]

[0203]

[0204] [Chemical Formula 6-8]

[0205]

[0206] [Chemical Formulas 6-9]

[0207]

[0208] [Chemical Formula 6-10]

[0209]

[0210] [Chemical Formula 6-11]

[0211]

[0212] [Chemical Formula 6-12]

[0213]

[0214] [Chemical Formula 6-13]

[0215]

[0216] [Chemical Formula 6-14]

[0217]

[0218] [Chemical Formula 6-15]

[0219]

[0220] [Chemical Formula 6-16]

[0221]

[0222] [Chemical Formula 6-17]

[0223]

[0224] [Chemical Formula 6-18]

[0225]

[0226] [Chemical Formula 6-19]

[0227]

[0228] [Chemical Formula 6-20]

[0229]

[0230] [Chemical Formula 6-21]

[0231]

[0232] [Chemical Formula 6-22]

[0233]

[0234] Specifically, the compounds represented by chemical formula 7 of the present invention may include at least one of the following structures.

[0235] [Chemical Formula 7-1]

[0236]

[0237] 3-Methyldiphenylamine, TCI Corporation

[0238] [Chemical Formula 7-2]

[0239]

[0240] 2-Aminodiphenylamine, TCI Corporation

[0241] [Chemical Formula 7-3]

[0242]

[0243] 4-Hydroxydiphenylamine, TCI Corporation

[0244] [Chemical Formula 7-4]

[0245]

[0246] 3-Methoxydiphenylamine, TCI Corporation

[0247] [Chemical Formula 7-5]

[0248]

[0249] 2,4-Diaminodiphenylamine, TCI Corporation

[0250] [Chemical Formula 7-6]

[0251]

[0252] 4-Methoxy-2-methyldiphenylamine, TCI Corporation [Chemical Formula 7-7]

[0253]

[0254] N-Phenyl-2-naphthylamine, TCI Corporation

[0255] [Chemical Formulas 7-8]

[0256]

[0257] Bis(3,4-dimethylphenyl)amine, TCI Corporation [Chemical Formula 7-9]

[0258]

[0259] 4,4'-Dimethoxydiphenylamine, TCI Corporation

[0260] [Chemical Formula 7-10]

[0261]

[0262] N,N'-Diphenyl-1,4-phenylenediamine, TCI Corporation [Chemical Formula 7-11]

[0263]

[0264] 3-Trifluoromethyl-4'-methoxydiphenylamine, TCI Corporation [Chemical Formula 7-12]

[0265]

[0266] 2,2'-Dinaphthylamine, TCI Corporation

[0267] [Chemical Formula 7-13]

[0268]

[0269] Bis(4-tert-butylphenyl)amine, TCI Corporation

[0270] [Chemical Formula 7-14]

[0271]

[0272] 4-(2-Octylamino)diphenylamine, TCI Corporation

[0273] [Chemical Formula 7-15]

[0274]

[0275] Bis(4-Biphenyl)amine, TCI Corporation

[0276] [Chemical Formula 7-16]

[0277]

[0278] N,N'-Diphenylbenzidine, TCI Corporation

[0279] [Chemical Formula 7-17]

[0280]

[0281] N,N'-Di-2-naphthyl-1,4-phenylenediamine, TCI

[0282] [Chemical Formula 7-18]

[0283]

[0284] bis[4-(hexyloxy)phenyl]amine, TCI Corporation

[0285] The compounds represented by chemical formula 8 may be suitably selected without affecting the purpose of the invention, but preferably include at least one of the compounds represented by chemical formulas 8-1 to 8-11.

[0286] [Chemical Formula 8-1]

[0287]

[0288] [Chemical Formula 8-2]

[0289]

[0290] [Chemical Formula 8-3]

[0291]

[0292] Where m8 is an integer from 1 to 20.

[0293] [Chemical Formula 8-4]

[0294]

[0295] [Chemical Formula 8-5]

[0296]

[0297] [Chemical Formula 8-6]

[0298]

[0299] [Chemical Formula 8-7]

[0300]

[0301] Where m8 is an integer from 1 to 20.

[0302] [Chemical Formula 8-8]

[0303]

[0304] Where m8 is an integer from 1 to 20.

[0305] [Chemical Formulas 8-9]

[0306]

[0307] Where m8 is an integer from 1 to 20.

[0308] [Chemical Formulas 8-10]

[0309]

[0310] Where m8 is an integer from 1 to 20.

[0311] [Chemical Formula 8-11]

[0312]

[0313] Where m8 is an integer from 1 to 20.

[0314] The compound represented by chemical formula 8 can improve the light conversion efficiency, color purity and uniformity of the coating film formed by the light conversion ink composition, and can suppress the aggregation of scattering particles when the light conversion ink composition contains scattering particles.

[0315] The compounds represented by chemical formula 9 may be suitably selected without affecting the purpose of the invention, but preferably include at least one of the compounds represented by the following chemical formulas 9-1 to 9-23.

[0316] [Chemical Formula 9-1]

[0317]

[0318] [Chemical Formula 9-2]

[0319]

[0320] [Chemical Formula 9-3]

[0321]

[0322] [Chemical Formula 9-4]

[0323]

[0324] [Chemical Formula 9-5]

[0325]

[0326] [Chemical Formula 9-6]

[0327]

[0328] [Chemical Formula 9-7]

[0329]

[0330] [Chemical Formula 9-8]

[0331]

[0332] [Chemical Formula 9-9]

[0333]

[0334] [Chemical Formulas 9-10]

[0335]

[0336] [Chemical Formula 9-11]

[0337]

[0338] [Chemical Formula 9-12]

[0339]

[0340] [Chemical Formula 9-13]

[0341]

[0342] [Chemical Formula 9-14]

[0343]

[0344] [Chemical Formula 9-15]

[0345]

[0346] [Chemical Formula 9-16]

[0347]

[0348] [Chemical Formula 9-17]

[0349]

[0350] [Chemical Formula 9-18]

[0351]

[0352] [Chemical Formula 9-19]

[0353]

[0354] [Chemical Formula 9-20]

[0355]

[0356] [Chemical Formula 9-21]

[0357]

[0358] [Chemical Formula 9-22]

[0359]

[0360] [Chemical Formula 9-23]

[0361]

[0362] Based on 100% by weight of the total solid content of the light-conversion ink composition, the content of compounds represented by Chemical Formula 1 and Chemical Formulas 6 to 9 can be greater than 0.1% by weight and less than 15% by weight, preferably in the range of 0.01% to 10% by weight. When the content of compounds represented by Chemical Formula 1 and Chemical Formulas 6 to 9 is within the above range, it improves light conversion efficiency and is beneficial in terms of changes in blue light absorbance and droplet size, prevention of surface foreign matter formation, and viscosity and particle size of the light-conversion ink composition. It also benefits inkjet ejection performance, nozzle wettability, lightfastness, heat resistance, high-temperature and high-humidity stability, and viscosity stability. Therefore, the content within the above range is preferred. Furthermore, when the content of the compounds is within the above range, it can further improve light conversion efficiency and coating uniformity, and when the light-conversion ink composition contains scattering particles, it can further suppress the aggregation of scattering particles.

[0363] Compounds with chemical formula 11

[0364] The light conversion ink composition according to the present invention may also contain a compound represented by chemical formula 11.

[0365] [Chemical Formula 11]

[0366]

[0367] In chemical formula 11,

[0368] Z8 is a substituted or unsubstituted alkyl group having 1 to 30 carbon atoms, a substituted or unsubstituted cycloalkyl group having 1 to 30 carbon atoms, a substituted or unsubstituted aryl group having 6 to 30 carbon atoms, a substituted or unsubstituted alkenyl group having 2 to 30 carbon atoms, a substituted or unsubstituted alkynyl group having 2 to 30 carbon atoms, a substituted or unsubstituted alkoxy group having 1 to 10 carbon atoms, a substituted or unsubstituted alkyl ester group having 2 to 30 carbon atoms, a substituted or unsubstituted heteroaryl group having 4 to 30 carbon atoms, a substituted or unsubstituted thioester group having 1 to 30 carbon atoms, a substituted or unsubstituted silyl ester group having 1 to 30 carbon atoms, a thioether group, or a silyl group;

[0369] R 89 and R 810 Each is independently a direct bond, substituted or unsubstituted, of an alkylene group having 1 to 30 carbon atoms, -OR 811 -、-OC(=O)R 812 -、-(OCH2CH2) p8 - or -(OCH2CH2CH2) q8 -;

[0370] Q 81 and Q 82 Each can be a direct bond, an oxygen atom, a sulfur atom, or -NH-;

[0371] D8 represents an oxygen atom, a sulfur atom, or is equal to NH;

[0372] R 811 A substituted or unsubstituted alkylene group having 1 to 30 carbon atoms;

[0373] R 812 A substituted or unsubstituted alkylene group having 4 to 30 carbon atoms;

[0374] p8 and q8 are each independent integers from 1 to 150.

[0375] The advantage of the compound represented by chemical formula 11 is that it fully protects the unprotected portion of the shell surface, thereby preventing the oxidation of quantum dots during thermal processes in the manufacturing of the light conversion laminate substrate, thus improving light efficiency.

[0376] The compounds represented by chemical formula 11 may be suitably selected without affecting the purpose of the invention, and preferably include at least one of the compounds represented by the following chemical formulas 11-1 to 11-7.

[0377] [Chemical Formula 11-1]

[0378]

[0379] [Chemical Formula 11-2]

[0380]

[0381] [Chemical Formula 11-3]

[0382]

[0383] [Chemical Formula 11-4]

[0384]

[0385] [Chemical Formula 11-5]

[0386]

[0387] [Chemical Formula 11-6]

[0388]

[0389] [Chemical Formula 11-7]

[0390]

[0391] Based on the total weight of the solid components in the light conversion ink composition, the content of the compound represented by Formula 11 can be from 0.1% to 15%. When the content of the compound represented by Formula 11 is within the above range, not only is the light efficiency improved, but it also benefits the dispersion of scattering particles and their stability over time.

[0392] Scattering particles

[0393] The light-converting ink composition according to the present invention may also contain scattering particles.

[0394] The scattering particles can be made of conventional inorganic materials, and preferably can contain metal oxides with an average particle size of 50 to 1000 nm.

[0395] Metal oxides can be, but are not limited to, oxides of a metal selected from the group consisting of Li, Be, B, Na, Mg, Al, Si, K, Ca, Sc, V, Cr, Mn, Fe, Ni, Cu, Zn, Ga, Ge, Rb, Sr, Y, Mo, Cs, Ba, La, Hf, W, Tl, Pb, Ce, Pr, Nd, Pm, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Ti, Sb, Sn, Zr, Nb, Ce, Ta, In, and combinations thereof.

[0396] Specifically, it can be selected from the group consisting of Al2O3, SiO2, ZnO, ZrO2, BaTiO3, TiO2, Ta2O5, Ti3O5, ITO, IZO, ATO, ZnO-Al, Nb2O3, SnO, MgO, BaSO4, and combinations thereof. If desired, materials that have been surface-treated with compounds containing unsaturated bonds, such as acrylates, can also be used.

[0397] When the light conversion ink composition according to the invention contains scattering particles, the path of light emitted from the luminescent particles can be increased by the scattering particles, thereby increasing the overall light efficiency in the light conversion coating; therefore, it is preferable to include scattering particles. In this regard, the light conversion ink composition of the invention preferably contains at least one selected from TiO2, SiO2, ZnO and BaSO4 as scattering particles.

[0398] The scattering particles can have an average particle size of 50 to 1000 nm, with internal scattering particles having an average particle size in the range of 100 to 500 nm being preferred. In this case, if the particles are too small, sufficient scattering effect of the light emitted from the quantum dots cannot be expected; conversely, if they are too large, they will sink into the composition or a uniformly sized self-emissive layer surface cannot be obtained. Therefore, it is appropriate to adjust them to the ranges mentioned above for use.

[0399] Based on 100% by weight of the total solids in the light-conversion ink composition, the content of scattering particles can be 0.5 to 20% by weight, preferably 1 to 15% by weight, and more preferably 2 to 10% by weight. When the content of scattering particles is within the above range, the effect of increasing luminous intensity can be maximized; therefore, a content within the above range is preferred. If the content of scattering particles is below the above range, it may be difficult to obtain the desired luminous intensity, and if the content of scattering particles exceeds the above range, the transmittance of blue illumination light is significantly reduced, resulting in the problem that the light conversion of the luminescent particles does not function properly. Therefore, it is preferable to use it appropriately within the above range.

[0400] Photopolymerization initiator

[0401] The light conversion ink composition according to an embodiment of the present invention may further contain a photopolymerization initiator.

[0402] In one embodiment of the present invention, the type of photopolymerization initiator is not particularly limited as long as it can polymerize polymerizable monomers. For example, considering factors such as polymerization characteristics, initiation efficiency, absorption wavelength, availability, and price, the photopolymerization initiator is preferably at least one compound selected from the group consisting of acetophenone compounds, benzophenone compounds, triazine compounds, biimidazole compounds, oxime compounds, thioxanone compounds, and phosphine oxide compounds.

[0403] For example, to cure films thicker than 5 μm, oxime compounds or phosphine oxide compounds can be used, which can ensure better physical properties of the cured film in terms of curing density and surface roughness.

[0404] Specific examples of oxime compounds may include o-ethoxycarbonyl-α-oxyimino-1-phenylprop-1-one, with Irgacure OXE 01 and OXE 02 from BASF being representative commercially available products.

[0405] Specific examples of phosphine oxide compounds may include Darocur TPO and Lucirin TPO from BASF as trimethylbenzoylphenylphosphine oxide.

[0406] Based on 100% by weight of the total solid components of the light-conversion ink composition, the content of the photopolymerization initiator can be from 0.1% to 10% by weight, preferably from 0.5% to 8% by weight. If the content of the photopolymerization initiator is within the above range, the photosensitivity of the light-conversion ink composition is improved, the exposure time is shortened, and thus productivity is improved; therefore, a content within the above range is preferred. When the content of the photopolymerization initiator is below the above range, insufficient photocuring occurs, resulting in insufficient hardness. Furthermore, when the content of the photopolymerization initiator exceeds the above range, the decrease in the light conversion efficiency of the luminescent particles caused by the photopolymerization initiator increases sharply, leading to a problem where the desired luminous intensity cannot be obtained. Therefore, using the content within the above range is beneficial for improving the intensity of the pixel portion and the smoothness of the pixel portion surface.

[0407] The photopolymerization initiator may also contain a photopolymerization initiation aid to improve the photosensitivity of the photoconversion ink composition according to the invention. When a photopolymerization initiation aid is included, it is advantageous to further improve photosensitivity, thereby increasing productivity.

[0408] Photopolymerization initiators may preferably be at least one compound selected from the group consisting of amine compounds, carboxylic acid compounds, and organosulfur compounds having a thiol group, but are not limited thereto.

[0409] Photopolymerization initiation aids may be appropriately added and used within the scope that does not affect the effects of the present invention.

[0410] additive

[0411] In addition to the components described above, the light conversion ink composition according to an embodiment of the present invention may also contain additives such as surfactants and adhesion promoters to improve the flatness or adhesion of the coating film.

[0412] When the light conversion ink composition of the present invention contains a surfactant, it has the advantage of improving the flatness of the coating film. For example, surfactants such as BM-1000, BM-1100 (BM Chemie), Fluorad FC-135 / FC-170C / FC-430 (Sumitomo 3M Co., Ltd.), SH-28PA / -190 / -8400 / SZ-6032 (Toray Silicone Co., Ltd.) can be used, but are not limited thereto.

[0413] Adhesion promoters can be added to increase adhesion to a substrate and may include, but are not limited to, silane coupling agents having reactive substituents selected from the group consisting of carboxyl, methacryloyl, isocyanate, epoxy, and combinations thereof.

[0414] Furthermore, the light conversion ink composition of the present invention may also contain additives such as antioxidants, ultraviolet absorbers, and anti-coagulation agents without affecting the effect of the present invention. These additives are also added and used appropriately by those skilled in the art without affecting the effect of the present invention.

[0415] Antioxidants may include at least one of the following: phenolic compounds, phosphorus compounds, and sulfur compounds.

[0416] solvent

[0417] The light conversion ink composition according to an embodiment of the present invention may further contain a solvent, or it may be a solvent-free type. When the light conversion ink composition of the present invention contains a solvent, for example, based on 100% by weight of the total amount of the light conversion ink composition, the solvent content may be 20% by weight or less.

[0418] Preferably, the light conversion ink composition according to an embodiment of the present invention can be a solvent-free type that does not contain solvents, taking into account continuous processability.

[0419] Even though the light conversion composition of the present invention is a solvent-free type without solvents, it contains the above-mentioned polymerizable monomers, so the light properties and dispersibility of the light-emitting particles are excellent, and low viscosity can be achieved, thereby improving the nozzle spraying performance of the ink.

[0420] As solvents, ether or ester solvents, aliphatic saturated hydrocarbon solvents, halogenated hydrocarbon solvents, aromatic solvents, etc., can be used. For example, ethylene glycol monoalkyl ethers such as propylene glycol methyl ether acetate (PGMEA), ethylene glycol monoethyl ether acetate, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol monopropyl ether, and ethylene glycol monobutyl ether can be used; diethylene glycol dialkyl ethers such as diethylene glycol dimethyl ether, diethylene glycol diethyl ether, diethylene glycol dipropyl ether, and diethylene glycol dibutyl ether can be used; and methyl cellosolve acetate, ethyl cellosolve acetate, etc., can also be used. Ethylene glycol alkyl ether acetates such as ethylene glycol alkyl acetates; alkylene glycol alkyl ether acetates such as propylene glycol monopropyl ether acetate, methoxybutyl acetate, and methoxypentyl acetate; aromatic hydrocarbons such as benzene, toluene, xylene, and mesitylene; ketones such as methyl ethyl ketone, acetone, methyl pentyl ketone, methyl isobutyl ketone, and cyclohexanone; alcohols such as ethanol, propanol, butanol, hexanol, cyclohexanol, ethylene glycol, and glycerol; esters such as ethyl 3-ethoxypropionate and methyl 3-methoxypropionate; and cyclic esters such as γ-butyrolactone.

[0421] <Light conversion multilayer substrate, backlight unit, and image display device>

[0422] One embodiment of the present invention is a light conversion laminate substrate that absorbs light emitted from a light-emitting device and converts it into blue, green, or red light, and then emits the light, wherein the light conversion laminate substrate is formed using the above-mentioned light conversion ink composition.

[0423] Furthermore, the present invention can provide a light-converting pixel substrate, which is manufactured using the above-described light-converting ink composition and used as a color filter for red, green, and blue colors.

[0424] The light conversion stack substrate and / or light conversion pixel substrate can be formed by applying the above-mentioned light conversion ink composition to a predetermined area using an inkjet method and then curing the applied light conversion ink composition.

[0425] Examples of substrates can include, but are not limited to, substrates with flat surfaces, such as glass substrates, silicon substrates, polycarbonate substrates, polyester substrates, aramid substrates, polyamide-imide substrates, polyimide substrates, Al substrates, and GaAs substrates. These substrates can undergo pretreatment processes such as chemical treatment using chemicals like silane coupling agents, plasma treatment, ion plating, sputtering, vapor phase reaction treatment, and vacuum evaporation. When using silicon substrates or the like as substrates, charge-coupled devices (CCDs), thin-film transistors (TFTs), etc., can be formed on the surface of the silicon substrate or the like. Furthermore, a spacer matrix can be formed. Curing can be performed under thermosetting conditions.

[0426] For example, curing can be carried out at 100 to 250°C, preferably 150 to 230°C, for 5 to 30 minutes, preferably 10 minutes.

[0427] In order for ink to be ejected from a piezoelectric inkjet head, which is an example of an inkjet printer, and to form a suitable phase on a substrate, properties such as viscosity, flowability, and quantum dot particles need to be matched and balanced with the inkjet head. The piezoelectric inkjet head used in this invention is not limited, but it ejects ink having a droplet size of about 3 to 100 pL, preferably about 5 to 40 pL.

[0428] The appropriate viscosity of the light conversion ink composition of the present invention is about 3 to 50 cP, more preferably adjusted in the range of 7 to 40 cP.

[0429] When applied to a blue light source, the light conversion laminate substrate according to the present invention exhibits excellent light output.

[0430] One embodiment of the present invention is a green light-emitting device that emits green light, specifically green light with a wavelength of 500-600nm, but is not limited thereto.

[0431] Green light-emitting devices can be green light-emitting diodes (LEDs).

[0432] One embodiment of the present invention relates to a backlight unit, including a light conversion laminate substrate applied to a blue light source.

[0433] The backlight unit may also include common components such as light guide plates and reflectors.

[0434] One embodiment of the present invention relates to an image display device including a backlight unit.

[0435] The image display device of the present invention includes not only existing liquid crystal display devices, but also various other image display devices such as electroluminescent display devices, plasma display devices, and field emission display devices.

[0436] In addition, one embodiment of the present invention relates to a light conversion pixel comprising a cured product of the above-described light conversion ink composition.

[0437] For example, a pattern of the light conversion ink composition can be formed by including the steps of coating the light conversion ink composition onto a predetermined area by inkjet printing and curing the coated light conversion ink composition, thereby creating a light conversion pixel.

[0438] Experimental examples, including specific embodiments and comparative examples, are provided below to aid in understanding the invention. However, these are merely illustrative and do not limit the scope of the appended claims. Various changes and modifications can be made to the embodiments within the scope and concept of the invention, which will be apparent to those skilled in the art, and such changes and modifications naturally fall within the scope of the appended claims. Furthermore, the terms "%" and "parts" used below refer to content, and unless otherwise stated, all are by weight.

[0439] <Experimental Example I>

[0440] Synthesis example

[0441] A-1 Preparation Example: Synthesis and Dispersion Preparation of AgInGaS / GaS Core-Shell Type Luminescent Particles

[0442] A mixture was prepared by placing 0.0625 mmol silver iodide (AgI, 99.999%), 1.25 mmol gallium acetylacetonate (Ga(acac)3, 99.99%), and 1 mmol sulfur (99.998%) in 1.5 mL of 1-dodecyl mercaptan (DDT ≥ 98%) and 5 mL of oleylamine (OLA, 70%) in a three-necked flask. The mixture was heated to 120 °C for degassing, and then purged with N2 while simultaneously raising the temperature to the growth temperature of 240 °C. This temperature was maintained for 30 minutes to grow the AGS core QD. 0.01 mmol indium acetate (In(Ac)3, 99.99%) was added to the AGS core solution. The mixture was heated to 120 °C for degassing, and then purged with N2 while simultaneously raising the temperature to the growth temperature of 240 °C. This temperature was maintained for 10 minutes to grow the AIGS core QD.

[0443] The AIGS core QD was mixed with 7 ml of oleylamine, 0.1 mmol of gallium acetylacetonate (Ga(acac)3, 99.99%), and 0.1 mmol of 1,3-dimethylthiourea, and rapidly heated to 230 °C. Under inert conditions, the temperature was increased by 2 °C per minute to 280 °C. The solution was cooled back to room temperature and degassed for 30 minutes to remove unreacted sulfur compounds. The quantum dots were precipitated in ethanol, purified by centrifugation, and then dried under reduced pressure to obtain AgInGaS / GaS quantum dot powder. The obtained quantum dot powder was mixed with 1,6-hexanediol diacrylate in a 1:1 ratio to prepare an AgInGaS / GaS dispersion.

[0444] Examples, Comparative Examples, and Reference Examples: Preparation of Light Conversion Ink Compositions

[0445] The light conversion ink compositions (unit: wt%) of the examples, comparative examples, and reference examples were prepared by mixing the components according to the composition shown in Table 1 below.

[0446] [Table 1]

[0447]

[0448] [Table 2]

[0449]

[0450] -A-1: AgInGaS / GaS QD dispersion

[0451] -B-1: 1,6-Hexanediol diacrylate (Shin Nakamura Chemical Co., Ltd.)

[0452] -B-2: Polyethylene glycol diacrylate (Shin Nakamura Chemical Co., Ltd.)

[0453] -C: TiO2 (Huntsman, TR-88, particle size 220nm)

[0454] -D: Diphenyl(2,4,6-trimethylbenzoyl)phosphine oxide (Aldrich)

[0455] -E-1: SH8400 (Dow Corning Toray Silicone)

[0456] -E-2: A compound with chemical formula 2-1

[0457] -E-3: Compound with chemical formula 2-2

[0458] -E-4: Compounds with chemical formula 2-3

[0459] -E-5: Compounds with chemical formulas 2-4

[0460] -E-6: Compounds with chemical formulas 2-5

[0461] -E-7: Compounds with chemical formulas 2-6

[0462] -E-8: Compounds with chemical formulas 2-7

[0463] -E-9: Compounds with chemical formulas 2-8

[0464] -E-10: Compounds with chemical formulas 2-9

[0465] -E-11: A compound with chemical formula 2-10

[0466] -E-12: A compound with chemical formula 3-1

[0467] -E-13: A compound with chemical formula 3-2

[0468] -E-14: A compound with chemical formula 3-3

[0469] -E-15: A compound with chemical formula 4-1

[0470] -E-16: A compound with chemical formula 4-2

[0471] -E-17: A compound with chemical formula 4-3

[0472] -E-18: A compound with chemical formula 5-1

[0473] -E-19: 1,8-Diaminooctane (TCI Corporation)

[0474] -E-20: Polyethyleneimine, branched, molecular weight (MW) 1800 (Alfa Aesar) -F-1: Sumilizer-GP (Sumitomo Chemical)

[0475] Experimental Example

[0476] 1. Preparation of light conversion coating and measurement of light conversion efficiency

[0477] The light conversion ink compositions prepared in the examples and comparative examples were coated onto a 5cm × 5cm glass substrate using an inkjet printing method, and then used under nitrogen atmosphere with a 395nm blue LED at 4000mJ / cm². 2 The light conversion coating was prepared by irradiation followed by heating at 180°C for 30 minutes on a hot plate under nitrogen atmosphere.

[0478] The prepared light conversion coating was placed over a blue light source (XLamp XR-E LED, Royal blue 450, Cree), and the light conversion efficiency was measured using a luminance meter (CAS140CT Spectrometer, Instrument Systems) according to the following equation. The measurement results are listed in Table 3 below.

[0479]

[0480] 2. Changes in blue light absorbance

[0481] The prepared 5 ml light-conversion ink composition was placed in a 10 ml graduated cylinder and allowed to stand at room temperature for one day. The ink composition from the center was then collected, and the light-conversion coating was prepared as described above. The change rate of blue light absorbance at the same 10 μm was compared before and after standing. It can be concluded that as more TiO2 precipitation occurred, the blue light absorbance decreased, and storage stability became problematic.

[0482] The rate of change of blue light absorbance was measured based on the following criteria, and the results are shown in Table 3.

[0483] <Standard>

[0484] ○: Absorbance change is 0% or more and less than 3%.

[0485] △: Absorbance change is greater than 3% but less than 5%.

[0486] X: Absorbance change is greater than 5%.

[0487] 3. Check for changes in inkjet droplet size.

[0488] Using a Unijet inkjet printer, 20 pL of ink was dropped onto a well-shaped pattern substrate with a width of 30 μm, a length of 90 μm, and a depth of 10 μm for 5 minutes, then allowed to stand for 1 hour. Dropping was then resumed, and any changes in drop size were observed. Changes in drop size could indicate that the ink failed to fill the pattern properly or that the film thickness changed.

[0489] The droplet size change was measured based on the following criteria, and the results are shown in Table 3.

[0490] <Standard>

[0491] ○: Droplet size change is greater than 0 pL and less than 1 pL

[0492] △: Droplet size change is greater than 1 pL but less than 2 pL X: Droplet size change is greater than 2 pL

[0493] [Table 3]

[0494]

[0495] The experimental results above confirm that the composition of the embodiment containing the additive corresponding to the structure of Formula 1 has improved light conversion efficiency and minimal changes in blue light absorbance and droplet size compared to the comparative example without such additive.

[0496] Furthermore, it can be confirmed that, based on a total solid content of 100% by weight of the light conversion ink composition, the compositions of the examples containing 0.01 to 10% by weight of additives corresponding to the structure of Formula 1 exhibit superior performance compared to the reference examples where the content of the additives is not within this range.

[0497] <Experimental Example II>

[0498] Synthesis example

[0499] A-1 Preparation Example: Synthesis and Dispersion Preparation of AgInGaS / GaS Core-Shell Type Luminescent Particles

[0500] A mixture was prepared by placing 0.0625 mmol silver iodide (AgI, 99.999%), 1.25 mmol gallium acetylacetonate (Ga(acac)3, 99.99%), and 1 mmol sulfur (99.998%) in 1.5 mL of 1-dodecyl mercaptan (DDT ≥ 98%) and 5 mL of oleylamine (OLA, 70%) in a three-necked flask. The mixture was heated to 120 °C for degassing, and then purged with N2 while simultaneously raising the temperature to the growth temperature of 240 °C. This temperature was maintained for 30 minutes to grow the AGS core QD. 0.01 mmol indium acetate (In(Ac)3, 99.99%) was added to the AGS core solution. The mixture was heated to 120 °C for degassing, and then purged with N2 while simultaneously raising the temperature to the growth temperature of 240 °C. This temperature was maintained for 10 minutes to grow the AIGS core QD.

[0501] The AIGS core QD was mixed with 7 ml of oleylamine, 0.1 mmol of gallium acetylacetonate (Ga(acac)3, 99.99%), and 0.1 mmol of 1,3-dimethylthiourea, and rapidly heated to 230 °C. Under inert conditions, the temperature was increased by 2 °C per minute to 280 °C. The solution was cooled back to room temperature and degassed for 30 minutes to remove unreacted sulfur compounds. The quantum dots were precipitated in ethanol, purified by centrifugation, and then dried under reduced pressure to obtain AgInGaS / GaS quantum dot powder. The obtained quantum dot powder was mixed with 1,6-hexanediol diacrylate in a 1:1 ratio to prepare an AgInGaS / GaS dispersion.

[0502] Examples, Comparative Examples, and Reference Examples: Preparation of Light Conversion Ink Compositions

[0503] The light conversion ink composition (unit: wt%) was prepared by mixing the components according to the compositions shown in Tables 4 and 5 below.

[0504] [Table 4]

[0505]

[0506] [Table 5]

[0507]

[0508] -A-1: AgInGaS / GaS dispersion

[0509] -B-1: 1,6-Hexanediol diacrylate (Shin Nakamura Chemical Co., Ltd.)

[0510] -B-2: Polyethylene glycol diacrylate (Shin Nakamura Chemical Co., Ltd.)

[0511] -C: TiO2 (Huntsman, TR-88, particle size 220nm)

[0512] -D: Diphenyl(2,4,6-trimethylbenzoyl)phosphine oxide (Aldrich)

[0513] -E-1: SH8400 (Dow Corning Toray Silicone)

[0514] -E-2: Compound of formula 6-1 (N,N-diethyl-1,3-diaminopropane, TCI Corporation) -E-3: Compound of formula 6-2 (N,N-diisopropylethylenediamine, TCI Corporation)

[0515] -E-4: A compound with chemical formula 6-3 (N,N-dibutylethylenediamine, TCI Corporation)

[0516] -E-5: Compound with chemical formula 6-4 (3-(dibutylamino)propylamine, TCI Corporation)

[0517] -E-6: Compound with chemical formula 6-5 (N-(3-aminopropyl)diethanolamine, TCI Corporation)

[0518] -E-7: A compound with chemical formula 6-6 (N-(3-aminopropyl)-N-methylaniline, TCI Corporation)

[0519] -E-8: Compound with chemical formula 6-7 (N,N-diethyl-1,4-cyclohexanediamine, TCI Corporation)

[0520] -E-9: Compound with chemical formula 6-8 (N-(2-aminoethyl)-N-phenylaniline, Amadichem)

[0521] -E-10: Compounds with chemical formulas 6-9 (N-(3-aminopropyl)-N-benzyl-N-methylamine, Aldrich).

[0522] -E-11: Compound with chemical formula 6-10 (N,N-dibenzylethylenediamine, Syntechem).

[0523] -E-12: Compound with chemical formula 6-11 ((2-aminoethyl)bis(2-pyridylmethyl)amine, Amadichem).

[0524] -E-13: Compound with chemical formula 6-12 (bis(2-hydroxyethyl)hexylamine, Syntechem)

[0525] -E-14: Aminoacetaldehyde dimethyl acetal (Aldrich)

[0526] -E-15: 4-Aminobutyral dimethyl acetal (TCI Company)

[0527] -F: Sumilizer-GP (Sumitomo Chemical)

[0528] Experimental Example

[0529] 1. Preparation of light conversion coating and measurement of light conversion efficiency

[0530] The light conversion ink compositions prepared in the examples and comparative examples were coated onto a 5cm × 5cm glass substrate using an inkjet printing method, and then used under nitrogen atmosphere with a 395nm blue LED at 4000mJ / cm². 2 The light conversion coating was prepared by irradiation followed by heating at 180°C for 30 minutes on a hot plate under nitrogen atmosphere.

[0531] The prepared light conversion coating was placed over a blue light source (XLamp XR-E LED, Royal blue 450, Cree), and the light conversion efficiency was measured using a luminance meter (CAS140CT Spectrometer, Instrument Systems) according to the following equation. The measurement results are shown in Table 6 below.

[0532]

[0533] 2. Viscosity stability evaluation

[0534] The initial viscosity and viscosity after 1 day of storage were measured using an R-type viscometer (VISCOMETER MODEL RE120L SYSTEM, manufactured by Toki Sangyo) at 20 rpm and 30°C. Viscosity stability was evaluated based on the calculated viscosity change rate according to the following evaluation criteria, and the results are shown in Table 6 below.

[0535] <Viscosity stability evaluation criteria>

[0536] ○: Viscosity change rate is below 105%

[0537] △: Viscosity change rate exceeding 105% but below 110%

[0538] X: Viscosity change rate exceeds 110%

[0539] 3. Evaluation of particle size change rate

[0540] The initial average particle size and the average particle size after 1 day of storage at room temperature were measured using an ELSZ-2000ZS (manufactured by Otsuka). The stability of the average particle size change was evaluated based on the calculated particle size change rate according to the following evaluation criteria, and the results are shown in Table 6 below.

[0541] <Particle Size Variation Stability Evaluation Criteria>

[0542] ○: Particle size variation is less than 10 nm

[0543] △: Particle size variation exceeding 10nm but less than 20nm

[0544] X: Particle size variation exceeding 20nm

[0545] 4. Inspect surface characteristics

[0546] After the light conversion coating was prepared as described above, the surface was confirmed with an optical microscope and evaluated according to the following evaluation criteria. The results are shown in Table 6 below.

[0547] <Surface Property Evaluation Standards>

[0548] ○: No foreign objects were found.

[0549] △: Surface is opaque

[0550] X: Foreign object found

[0551] [Table 6]

[0552] Evaluation results Light conversion efficiency viscosity change rate Particle size change rate Surface foreign matter Example II-1 33％ ○ ○ ○ Example II-2 34％ ○ ○ ○ Example II-3 33％ ○ ○ ○ Example II-4 35％ ○ ○ ○ Example II-5 34％ ○ ○ ○ Example II-6 33％ ○ ○ ○ Example II-7 35％ ○ ○ ○ Example II-8 33％ ○ ○ ○ Example II-9 33％ ○ ○ ○ Example II-10 34％ ○ ○ ○ Example II-11 34％ ○ ○ ○ Example II-12 34％ ○ ○ ○ Comparative Example II-1 25％ X X X Comparative Example II-2 30％ X △ △ Comparative Example II-3 30％ X △ △ Reference Example II-1 26％ △ △ △ Reference Example II-2 35％ △ △ △

[0553] Based on experimental data, the light-conversion ink composition of the examples containing the compound represented by Chemical Formula 6 exhibits a viscosity change rate of less than 105% and a particle size change of less than 10 nm, while the light-conversion ink composition of the comparative examples not containing the compound represented by Chemical Formula 6 exhibits a viscosity change rate of more than 110% and a particle size change of more than 20 nm. Therefore, it can be seen that the light-conversion ink composition of the examples containing the compound represented by Chemical Formula 6 has improved viscosity and particle size stability compared to the light-conversion ink composition of the comparative examples not containing this compound.

[0554] Furthermore, the coating film formed by the light conversion ink composition of the embodiment containing the compound represented by Chemical Formula 6 has a light conversion efficiency of over 30% and no foreign matter appears on the coating film surface, while the coating film formed by the light conversion ink composition of the comparative example not containing the compound represented by Chemical Formula 6 has a light conversion efficiency of 25 to 30% and foreign matter appears on the coating surface. Therefore, it can be seen that the coating film formed by the light conversion ink composition of the embodiment containing the compound represented by Chemical Formula 6 has improved light conversion efficiency and improved surface foreign matter characteristics compared to the coating film formed by the light conversion ink composition of the comparative example not containing the compound.

[0555] Furthermore, the photoconversion ink compositions of the examples containing more than 0.1% by weight and less than 15% by weight of the compound represented by Chemical Formula 6, based on the total weight of the solid components in the composition, exhibit a viscosity change rate of less than 105% and a particle size change of less than 10 nm. In contrast, the photoconversion ink compositions of the reference examples containing 0.1% by weight and 15% by weight of the compound represented by Chemical Formula 6, respectively, based on the total weight of the solid components in the composition, exhibit a viscosity change rate greater than 105% and less than 110%, and a particle size change greater than 10 nm and less than 20 nm. Therefore, it can be seen that the photoconversion ink compositions of the examples containing more than 0.1% by weight and less than 15% by weight of the compound represented by Chemical Formula 6, based on the total weight of the solid components in the composition, have improved viscosity and particle size stability compared to the photoconversion ink compositions of the reference examples where the content of this compound is not within the aforementioned range.

[0556] Furthermore, the coating film formed by the light conversion ink composition of the embodiment containing more than 0.1 wt% and less than 15 wt% of the compound represented by Chemical Formula 6 based on the total weight of the solid components in the composition has a light conversion efficiency of over 30% and no foreign matter appears on the coating film surface. In contrast, the coating films formed by the light conversion ink compositions of the reference examples containing 0.1 wt% and 15 wt% of the compound represented by Chemical Formula 6 based on the total weight of the solid components in the composition have a light conversion efficiency of 26 to 35%, but the coating film surface is opaque. Therefore, it can be seen that the coating film formed by the light conversion ink composition of the embodiment containing more than 0.1 wt% and less than 15 wt% of the amine compound represented by Chemical Formula 6 based on the total weight of the solid components in the composition has improved light conversion efficiency and improved surface foreign matter characteristics compared to the coating film formed by the light conversion ink composition of the reference examples where the content of the compound is not within the above range.

[0557] <Experimental Example III>

[0558] Synthesis example

[0559] A-1 Preparation Example: Synthesis and Dispersion Preparation of AgInGaS / GaS Core-Shell Type Luminescent Particles

[0560] A mixture was prepared by placing 0.0625 mmol silver iodide (AgI, 99.999%), 1.25 mmol gallium acetylacetonate (Ga(acac)3, 99.99%), and 1 mmol sulfur (99.998%) in 1.5 mL of 1-dodecyl mercaptan (DDT ≥ 98%) and 5 mL of oleylamine (OLA, 70%) in a three-necked flask. The mixture was heated to 120 °C for degassing, and then purged with N2 while simultaneously raising the temperature to the growth temperature of 240 °C. This temperature was maintained for 30 minutes to grow the AGS core QD. 0.01 mmol indium acetate (In(Ac)3, 99.99%) was added to the AGS core solution. The mixture was heated to 120 °C for degassing, and then purged with N2 while simultaneously raising the temperature to the growth temperature of 240 °C. This temperature was maintained for 10 minutes to grow the AIGS core QD.

[0561] The AIGS core QD was mixed with 7 ml of oleylamine, 0.1 mmol of gallium acetylacetonate (Ga(acac)3, 99.99%), and 0.1 mmol of 1,3-dimethylthiourea, and rapidly heated to 230 °C. Under inert conditions, the temperature was increased by 2 °C per minute to 280 °C. The solution was cooled back to room temperature and degassed for 30 minutes to remove unreacted sulfur compounds. The quantum dots were precipitated in ethanol, purified by centrifugation, and then dried under reduced pressure to obtain AgInGaS / GaS quantum dot powder. The obtained quantum dot powder was mixed with 1,6-hexanediol diacrylate in a 1:1 ratio to prepare an AgInGaS / GaS dispersion.

[0562] Compounds from E-2 to E-9

[0563] The following compounds, E-2 to E-9, were purchased from TCI.

[0564] Examples, Comparative Examples, and Reference Examples: Preparation of Light Conversion Ink Compositions

[0565] The light conversion ink composition was prepared by mixing the components as shown in Table 7 below (unit: wt%).

[0566] [Table 7]

[0567]

[0568] -A-1: AgInGaS / GaS dispersion

[0569] -B-1: 1,6-Hexanediol diacrylate (Shin Nakamura Chemical Co., Ltd.)

[0570] -B-2: Polyethylene glycol diacrylate (Shin Nakamura Chemical Co., Ltd.)

[0571] -C: TiO2 (Huntsman, TR-88, particle size 220nm)

[0572] -D: Diphenyl(2,4,6-trimethylbenzoyl)phosphine oxide (Aldrich)

[0573] -E-1: SH8400 (Dow Corning Toray Silicone)

[0574] -E-2: A compound with chemical formula 7-1

[0575] -E-3: A compound with chemical formula 7-2

[0576] -E-4: A compound with chemical formula 7-3

[0577] -E-5: Compound with chemical formula 7-4

[0578] -E-6: Compounds with chemical formulas 7-9

[0579] -E-7: Compounds with chemical formula 7-11

[0580] -E-8: A compound with chemical formula 7-14

[0581] -E-9: Compounds with chemical formula 7-18

[0582] -E-10: Dicyclohexylamine (TCI Company)

[0583] -F-1: Sumilizer-GP (Sumitomo Chemical)

[0584] Experimental Example

[0585] 1. Preparation of light conversion coating and measurement of light conversion efficiency

[0586] The light conversion ink compositions prepared in the examples and comparative examples were coated onto a 5cm × 5cm glass substrate using an inkjet printing method, and then used under nitrogen atmosphere with a 395nm blue LED at 4000mJ / cm². 2 The light conversion coating was prepared by irradiation followed by heating at 180°C for 30 minutes on a hot plate under nitrogen atmosphere.

[0587] The prepared light conversion coating was placed above a blue light source (XLamp XR-E LED, Royal blue 450, Cree), and the light conversion efficiency was measured using a luminance meter (CAS140CT Spectrometer, Instrument Systems) according to the following equation. The measurement results are listed in the table below.

[0588]

[0589] 2. Lightfastness evaluation

[0590] The light conversion coating prepared as described above was placed over a blue light source (XLamp XR-E LED, Royal blue 450, Cree) for 1 hour, and the retention rate (%) relative to the initial light conversion efficiency was then confirmed to evaluate lightfastness, as shown in the table below.

[0591] 3. Heat resistance evaluation

[0592] The light conversion coating prepared above was placed under a blue light source (XLamp XR-E LED, Royal blue 450 illuminance 3mW / cm²). 2 After being placed on top of the Cree Optical Converter, the luminance was measured using a luminance meter (CAS140CT Spectrometer, Instrument Systems). The same optical converter sheet was heated in a heating oven at 180°C for 30 minutes under nitrogen and atmospheric conditions, and the luminance was measured using the same method as described above. The heat resistance was evaluated by calculating the luminance retention rate after heating based on the following mathematical formula 1, as shown in the table below.

[0593] [Mathematical Expression 1]

[0594] Brightness retention rate = (Brightness after 30 minutes of treatment at 180℃) / (Brightness before 30 minutes of treatment at 180℃) × 100

[0595] 4. Evaluation of high temperature and high humidity resistance

[0596] After depositing SiOx on the light conversion coating prepared above, it was placed under a blue light source (XLamp XR-E LED, Royalblue 450, illuminance 3mW / cm²). 2Above the Cree company, the brightness was measured using a luminance meter (CAS140CT Spectrometer, Instrument Systems). After exposing the same light conversion sheet to a high-temperature, high-humidity treatment apparatus (TH-PE manufactured by JeioTech) for 24 hours at 80°C and 85% humidity, the brightness was measured using the same method described above. The high-temperature, high-humidity resistance was evaluated by calculating the brightness retention rate after high-temperature, high-humidity treatment based on the following mathematical formula 2. It can be determined that the higher the value, the better the high-temperature, high-humidity resistance.

[0597] [Mathematical Expression 2]

[0598] Brightness retention rate = (Brightness after 24 hours of treatment at 80℃ and 85% humidity) / (Brightness before 24 hours of treatment at 80℃ and 85% humidity) × 100

[0599] 5. Viscosity stability evaluation

[0600] The initial viscosity of the photoconversion ink composition and the viscosity after one day of storage at room temperature were measured using an R-type viscometer (VISCOMETER MODEL RE120L SYSTEM, manufactured by Toki Sangyo) at 20 rpm and 30°C, respectively. Viscosity stability was evaluated based on the calculated viscosity change rate according to the following evaluation criteria, and the results are shown in the table below.

[0601] <Viscosity stability evaluation criteria>

[0602] ○: Viscosity change rate is below 105%

[0603] △: Viscosity change rate exceeding 105% but below 110%

[0604] X: Viscosity change rate exceeds 110%

[0605] [Table 8]

[0606]

[0607] The experimental results above confirm that the compositions of the embodiments containing compounds with structures corresponding to Chemical Formula 7 of this application exhibit superior performance and viscosity stability in all aspects, including light conversion efficiency, lightfastness, heat resistance, high temperature and high humidity stability, compared to Comparative Examples 1 to 2 which do not contain the compound or contain compounds with other structures.

[0608] Furthermore, it can be confirmed that the compositions of the examples containing 0.01 to 10% by weight of a compound corresponding to the structure of Formula 7, based on a total solid content of 100% of the light conversion ink composition, have superior effects compared to the reference examples where the content of the compound is not within the above range.

[0609] <Experimental Example IV>

[0610] Synthesis example

[0611] A-1 Preparation Example: Synthesis and Dispersion Preparation of AgInGaS / GaS Core-Shell Type Luminescent Particles

[0612] A mixture was prepared by placing 0.0625 mmol silver iodide (AgI, 99.999%), 1.25 mmol gallium acetylacetonate (Ga(acac)3, 99.99%), and 1 mmol sulfur (99.998%) in 1.5 mL of 1-dodecyl mercaptan (DDT ≥ 98%) and 5 mL of oleylamine (OLA, 70%) in a three-necked flask. The mixture was heated to 120 °C for degassing, and then purged with N2 while simultaneously raising the temperature to the growth temperature of 240 °C. This temperature was maintained for 30 minutes to grow the AGS core QD. 0.01 mmol indium acetate (In(Ac)3, 99.99%) was added to the AGS core solution. The mixture was heated to 120 °C for degassing, and then purged with N2 while simultaneously raising the temperature to the growth temperature of 240 °C. This temperature was maintained for 10 minutes to grow the AIGS core QD.

[0613] The AIGS core QD was mixed with 7 ml of oleylamine, 0.1 mmol of gallium acetylacetonate (Ga(acac)3, 99.99%), and 0.1 mmol of 1,3-dimethylthiourea, and rapidly heated to 230 °C. Under inert conditions, the temperature was increased by 2 °C per minute to 280 °C. The solution was cooled back to room temperature and degassed for 30 minutes to remove unreacted sulfur compounds. The quantum dots were precipitated in ethanol, purified by centrifugation, and then dried under reduced pressure to obtain AgInGaS / GaS quantum dot powder. The obtained quantum dot powder was mixed with 1,6-hexanediol diacrylate in a 1:1 ratio to prepare an AgInGaS / GaS dispersion.

[0614] Examples and Comparative Examples: Preparation of Light Conversion Ink Compositions

[0615] The light conversion ink composition (unit: wt%) was prepared by mixing the components according to the compositions shown in Tables 9 and 10 below.

[0616] [Table 9]

[0617]

[0618] [Table 10]

[0619]

[0620] -A-1: AgInGaS / GaS dispersion

[0621] -B-1: 1,6-Hexanediol diacrylate (Shin Nakamura Chemical Co., Ltd.)

[0622] -B-2: Polyethylene glycol diacrylate (Shin Nakamura Chemical Co., Ltd.)

[0623] -C: TiO2 (Huntsman, TR-88, particle size 220nm)

[0624] -D: Diphenyl(2,4,6-trimethylbenzoyl)phosphine oxide (Aldrich)

[0625] -E-1: SH8400 (Dow Corning Toray Silicone)

[0626] -E-2: Compound represented by chemical formula 8-1 (2-(2-(2-ethoxyethoxy)ethoxy)ethylamine, Aldrich).

[0627] -E-3: Compound represented by chemical formula 8-2 (mPEG5-NH2, Aldrich).

[0628] -E-4: Compound represented by chemical formula 8-3 (poly(ethylene glycol) methyl etheramine, Aldrich, Mn=500)

[0629] -E-5: Compounds represented by chemical formula 8-4 (amino- 4-Acid (Aldrich)

[0630] -E-6: Compound represented by chemical formula 8-5 (amino-PEG4-yne, Aldrich).

[0631] -E-7: Compound represented by chemical formula 8-6 (amino-PEG3, TCI Corporation)

[0632] -E-8: Compound represented by chemical formula 8-7 (poly(ethylene glycol)diamine, Aldrich, Mn=400)

[0633] -E-9: Compound represented by chemical formula 8-8 (SH-PEG-NH2, Biochempeg, Mn=400)

[0634] -E-10: The compound represented by chemical formula 8-9 (2,5,8,11,14-pentaoxahexadecan-16-yl 2-aminoacetate).

[0635] -E-11: The compound represented by chemical formula 8-10 (2,5,8,11-tetraoxatridecan-13-yl 3-aminopropanoate).

[0636] -E-12: Compound represented by chemical formula 8-11 (3-amino-N-(2,5,8,11-tetraoxatridecane-13-yl)acrylamide)

[0637] -E-13: 1-Aminodecane (TCI Company)

[0638] -E-14: Methoxylated polyethylene glycol 1000 propionic acid (Aldrich)

[0639] -E-15: 36-Amine (Aldrich)

[0640] -F: Sumilizer-GP (Sumitomo Chemical)

[0641] -G: Compound represented by chemical formula 11-1 (2-(2-methoxyethoxy)ethyl 3-mercaptopropionate)

[0642] Experimental Example

[0643] 1. Preparation of light conversion coating and evaluation of light conversion efficiency

[0644] The light conversion ink compositions prepared in the examples and comparative examples were coated onto a 5cm × 5cm glass substrate using an inkjet printing method, and then subjected to a 395nm blue LED at 4000mJ / cm² under nitrogen atmosphere. 2 The light conversion coating was prepared by irradiation followed by heating at 180°C for 30 minutes on a hot plate under nitrogen atmosphere.

[0645] The prepared light conversion coating was placed above a blue light source (XLamp XR-E LED, Royal blue 450, Cree), and the light conversion efficiency (A) was measured using a luminance meter (CAS140CT spectrometer, Instrument Systems) according to the following equation. The measurement results are listed in Table 11 below.

[0646]

[0647] In addition, by setting the light conversion efficiency (%) of the InP / ZnS core-shell type luminescent particles of Comparative Example 1 to 100%, the light conversion efficiency (%) of (B) which was improved from the measured light conversion efficiency result (A) is shown in Table 11.

[0648] 2. Evaluation of the full width at half maximum (FWHM) of the emission spectrum

[0649] The light conversion coating prepared above was placed over a blue light source (XLamp XR-E LED, Royal blue 450, Cree), and the full width at half maximum (FWHM) of the emission spectrum was measured using a luminance meter (CAS140CT Spectrometer, Instrument Systems), as shown in Table 11 below.

[0650] The measured full width at half maximum (FWHM) values ​​are shown in the table below. The lower the FWHM value, the better the color purity. In particular, when the FWHM is below 40 nm, even better color purity can be expected.

[0651] 3. Evaluation of coating uniformity

[0652] Using an inkjet printer from Unijet, 20 drops of 20 pL each were applied to a well-patterned substrate with a width of 30 μm, a length of 90 μm, and a depth of 10 μm. After one hour, adjacent pixels were coated in the same manner. The coated substrate was illuminated with a blue LED and heated in a heated oven for 30 minutes, in the same manner as disclosed in the fabrication of the light conversion coating and the measurement of light conversion efficiency. The film thickness of the two patterns was then measured using a film thickness gauge (Dektak, manufactured by Bluker), and the film thickness variation rate between the two patterns was calculated, as shown in Table 11 below.

[0653] <Evaluation Criteria>

[0654] ◎: No film thickness change rate

[0655] ○: Film thickness change rate exceeds 0% and is below 5%.

[0656] △: Film thickness change rate exceeds 5% but is less than 10%

[0657] X: Film thickness variation rate exceeds 10%

[0658] 4. Evaluation of TiO2 Dispersion

[0659] The cross-section of the prepared light conversion coating was cut open, and EDS (energy-dispersive X-ray spectroscopy) was used to confirm whether TiO2 agglomeration had occurred. The results are shown in Table 11 below. If TiO2 is not uniformly distributed in the coating, optical property degradation may occur.

[0660] <Evaluation Criteria>

[0661] ◎: No TiO2 aggregation occurred.

[0662] ○: TiO2 agglomeration area exceeds 0% and is below 5%

[0663] △: TiO2 agglomeration area exceeds 5% but is below 10%

[0664] X: TiO2 aggregation area exceeds 10%

[0665] [Table 11]

[0666]

[0667] Referring to Table 11, it can be seen that the light conversion ink compositions of the embodiments containing at least one of the compounds represented by chemical formulas 8-1 to 8-11 have a (A) light conversion efficiency of 31% to 37%, a full width at half maximum (FWHM) of 34 nm to 40 nm, a film thickness variation rate of less than 10%, and a TiO2 agglomeration area of ​​less than 10%.

[0668] Furthermore, the light conversion ink compositions of Comparative Examples IV-1 to IV-3, which contain compounds as additives that are different from those represented by Chemical Formula 8, have light conversion efficiencies of 21% (Comparative Example IV-2) and 24% (Comparative Example IV-1), respectively. These light conversion efficiencies are worse than those of the examples, or the film thickness variation rate exceeds 10% (Comparative Examples IV-1 and IV-3), and the TiO2 agglomeration area exceeds 10% (Comparative Examples IV-1 and IV-3). Therefore, it can be seen that there is a problem of decreased optical properties.

[0669] Therefore, it can be confirmed that the advantages of light conversion ink compositions containing compounds represented by chemical formula 8 are excellent light conversion efficiency and color purity, minimal film thickness variation, and prevention of agglomeration of scattering particles.

[0670] On the other hand, it can be seen that, compared with the light conversion ink composition of Example IV-12 which does not contain antioxidants, the light conversion ink compositions of Examples IV-1 to IV-11 which further contain antioxidants have (A) an increased light conversion efficiency of 3%p to 4%p, a decrease in full width at half maximum (FWHM) of 5nm to 6nm, and a reduction in film thickness variation rate and TiO2 agglomeration area.

[0671] Furthermore, it can be seen that, compared with the light conversion ink compositions of Examples IV-1 to IV-11 which only further contain antioxidants, the light conversion ink composition of Example IV-13 which further contains antioxidants and thiol compounds has a (A) light conversion efficiency increased by 2%p to 3%p, and the film thickness change rate and TiO2 agglomeration area are further reduced.

[0672] Therefore, the advantages of light conversion ink compositions that further include at least one of antioxidants and thiol compounds are excellent light conversion efficiency and color purity, minimal film thickness variation, and prevention of scattering particle aggregation.

[0673] Furthermore, it can be seen that, based on the total weight of solid components in the light conversion ink composition, the light conversion ink compositions of Examples IV-1 to IV-11 containing more than 0.1% by weight and less than 15% by weight of the compound represented by Chemical Formula 8 have superior (A) light conversion efficiency and reduced film thickness variation and TiO2 agglomeration area compared with the light conversion ink compositions of Reference Examples 1 and 2, which contain 0.1% by weight and 15% by weight of the compound, respectively.

[0674] Therefore, it can be seen that the advantages of a light conversion ink composition containing more than 0.1% by weight and less than 15% by weight of a compound represented by chemical formula 8, based on the total weight of the solid components in the light conversion ink composition, are that it has excellent light conversion efficiency, minimal film thickness variation, and prevents the aggregation of scattering particles.

[0675] <Experimental Example V>

[0676] Synthesis example

[0677] Preparation Example A: Synthesis of AgInGaS / GaS core-shell luminescent particles and preparation of dispersion

[0678] A mixture was prepared by placing 0.0625 mmol silver iodide (AgI, 99.999%), 1.25 mmol gallium acetylacetonate (Ga(acac)3, 99.99%), and 1 mmol sulfur (99.998%) in 1.5 mL of 1-dodecyl mercaptan (DDT ≥ 98%) and 5 mL of oleylamine (OLA, 70%) in a three-necked flask. The mixture was heated to 120 °C for degassing, and then purged with N2 while simultaneously raising the temperature to the growth temperature of 240 °C. This temperature was maintained for 30 minutes to grow the AGS core QD. 0.01 mmol indium acetate (In(Ac)3, 99.99%) was added to the AGS core solution. The mixture was heated to 120 °C for degassing, and then purged with N2 while simultaneously raising the temperature to the growth temperature of 240 °C. This temperature was maintained for 10 minutes to grow the AIGS core QD.

[0679] The AIGS core QD was mixed with 7 ml of oleylamine, 0.1 mmol of gallium acetylacetonate (Ga(acac)3, 99.99%), and 0.1 mmol of 1,3-dimethylthiourea, and rapidly heated to 230 °C. Under inert conditions, the temperature was increased by 2 °C per minute to 280 °C. The solution was cooled back to room temperature and degassed for 30 minutes to remove unreacted sulfur compounds. The quantum dots were precipitated in ethanol, purified by centrifugation, and then dried under reduced pressure to obtain AgInGaS / GaS quantum dot powder. The obtained quantum dot powder was mixed with 1,6-hexanediol diacrylate in a 1:1 ratio to prepare an AgInGaS / GaS dispersion.

[0680] Examples, Comparative Examples, and Reference Examples: Preparation of Light Conversion Ink Compositions

[0681] The light conversion ink composition was prepared by mixing the components according to the compositions shown in Tables 12 to 14 below (unit: wt%).

[0682] [Table 12]

[0683]

[0684] [Table 13]

[0685]

[0686] [Table 14]

[0687]

[0688] -A: AgInGaS / GaS dispersion according to the preparation example -B-1: 1,6-hexanediol diacrylate (Shin Nakamura Chemical) -B-2: polyethylene glycol diacrylate (Shin Nakamura Chemical) -C: TiO2 (Huntsman, TR-88, particle size 220 nm)

[0689] -D: Diphenyl(2,4,6-trimethylbenzoyl)phosphine oxide (Aldrich)

[0690] -E-1: SH8400 (Dow Corning Toray Silicone)

[0691] -E-2: Compound with chemical formula 9-1 (N,N-diethyl-1,3-diaminopropane, TCI Corporation)

[0692] -E-3: Compound with chemical formula 9-2 (N,N-diisopropylethylenediamine, TCI Corporation)

[0693] -E-4: A compound with chemical formula 9-3 (N,N-dibutylethylenediamine, TCI Corporation)

[0694] -E-5: Compound with chemical formula 9-4 (3-(dibutylamino)propylamine, TCI Corporation)

[0695] -E-6: Compound with chemical formula 9-5 (N-(3-aminopropyl)diethanolamine, TCI Corporation)

[0696] -E-7: Compound with chemical formula 9-6 (N-(3-aminopropyl)-N-methylaniline, TCI Corporation)

[0697] -E-8: Compound with chemical formula 9-7 (N,N-diethyl-1,4-cyclohexanediamine, TCI Corporation)

[0698] -E-9: Compound with chemical formula 9-8 (N-(2-aminoethyl)-N-phenylaniline, Amadicechem)

[0699] -E-10: Compound with chemical formula 9-9 (N-(3-aminopropyl)-N-benzyl-N-methylamine, Aldrich)

[0700] -E-11: Compound with chemical formulas 9-10 (N,N-dibenzylethylenediamine, Syntechem).

[0701] -E-12: Compound with chemical formula 9-11 ((2-aminoethyl)bis(2-pyridylmethyl)amine, Amadichem).

[0702] -E-13: Compound with chemical formula 9-12 (bis(2-hydroxyethyl)hexylamine, Syntechem)

[0703] -E-14: Compound with chemical formula 9-13 (2-(4-aminophenyl)ethylamine, TCI Corporation)

[0704] -E-15: Compound of formula 9-14 (2,2'-[1,2-phenylenebis(oxy)]diethylamine, Combi Blocks)

[0705] -E-16: Compound with chemical formula 9-15 (3,3',5,5'-tetramethylbenzidine, TCI Corporation)

[0706] -E-17: Compound with chemical formula 9-16 (1,8-diaminonaphthalene, TCI Corporation)

[0707] -E-18: Compound with chemical formula 9-17 (3,3'-dimethylnaphthidine, TCI Corporation)

[0708] -E-19: Compound with chemical formula 9-18 (6,6'-diamino-2,2'-bipyridine, TCI Corporation)

[0709] -E-20: Compound with chemical formula 9-19 (o-dianisidine, TCI).

[0710] -E-21: Compound with chemical formula 9-20 (2,2'-diamino-4,4'-bithiazole, TCI Corporation)

[0711] -E-22: Compound with chemical formula 9-21 (2,2'-bis(trifluoromethyl)benzidine, TCI Corporation)

[0712] -E-23: 1,8-Diaminooctane (TCI Corporation)

[0713] -E-24: N,N-Diethyl-1,4-cyclohexanediamine (TCI)

[0714] -F: Sumilizer-GP (Sumitomo Chemical)

[0715] Experimental Example

[0716] 1. Preparation of light conversion coating and measurement of light conversion efficiency

[0717] The light conversion ink compositions prepared in the examples and comparative examples were coated onto a 5cm × 5cm glass substrate using an inkjet printing method, and then used under nitrogen atmosphere with a 395nm blue LED at 4000mJ / cm². 2 The light conversion coating was prepared by irradiation followed by heating at 180°C for 30 minutes on a hot plate under nitrogen atmosphere.

[0718] The prepared light conversion coating was placed over a blue light source (XLamp XR-E LED, Royal blue 450, Cree), and the light conversion efficiency was measured using a luminance meter (CAS140CT Spectrometer, Instrument Systems) according to the following equation. The measurement results are listed in Table 15 below.

[0719]

[0720] 2. Full width at half maximum (FWHM) of the emission spectrum

[0721] The prepared light conversion coating was placed over a blue light source (XLamp XR-E LED, Royal blue 450, Cree), and the full width at half maximum (FWHM) of the emission spectrum was obtained by measuring the emission spectrum using a luminance meter (CAS140CT Spectrometer, Instrument Systems).

[0722] The measured full width at half maximum (FWHM) values ​​are shown in the table below. The lower the FWHM value, the better the color purity. In particular, when the FWHM is below 40 nm, even better color purity can be expected.

[0723] 3. Inkjet output performance

[0724] The light-conversion ink composition prepared above was filled into a Unijet inkjet printing machine. The printhead temperature was then fixed at 40°C, and ink was continuously ejected for 1 minute, followed by a 30-minute rest period, and then ejected again. The ejection performance was evaluated according to the following criteria.

[0725] <Evaluation Criteria>

[0726] ○: Can be re-ejected; droplets exhibit good straight-line propagation.

[0727] △: Can be ejected again, but produces a droplet curve.

[0728] X: Can no longer spit out

[0729] 4. Nozzle wettability

[0730] The light conversion ink composition prepared above was filled into the inkjet printing equipment of Unijet Company. The printhead temperature was then fixed at 40°C. After continuously ejecting ink for 30 minutes, it was confirmed whether the nozzle surface was wetted by the ink composition.

[0731] [Table 15]

[0732] Evaluation results Light conversion efficiency (%) Full width at half maximum (nm) Ejection performance Nozzle wettability Example V-1 33 38 ○ Not found Example V-2 33 37 ○ Not found Example V-3 33 37 ○ Not found Example V-4 34 38 ○ Not found Example V-5 34 37 ○ Not found Example V-6 32 38 ○ Not found Example V-7 32 37 ○ Not found Example V-8 34 37 ○ Not found Example V-9 34 37 ○ Not found Example V-10 34 38 ○ Not found Example V-11 34 37 ○ Not found Example V-12 35 38 ○ Not found Example V-13 34 37 ○ Not found Example V-14 35 37 ○ Not found Example V-15 35 37 ○ Not found Example V-16 35 37 ○ Not found Example V-17 34 38 ○ Not found Example V-18 35 38 ○ Not found Example V-19 33 38 ○ Not found Example V-20 34 37 ○ Not found Example V-21 34 37 ○ Not found Example V-22 34 37 ○ Not found Example V-23 36 38 ○ Not found Comparative Example V-1 24 46 X Appear Comparative Example V-2 30 37 X Appear Comparative Example V-3 30 37 X Appear Reference Example V-1 25 45 △ Partial appearance See Example V-2 36 37 △ Partial appearance

[0733] Based on experimental data, the light conversion ink composition of the examples containing the compound represented by Chemical Formula 9 exhibits a light conversion efficiency greater than 30% and a full width at half maximum (FWHM) of less than 40 nm, while the light conversion ink composition of the comparative examples not containing the compound represented by Chemical Formula 9 exhibits a light conversion efficiency of less than 30% and a FWHM greater than 40 nm. Therefore, it can be seen that the light conversion ink composition containing the compound represented by Chemical Formula 9 has improved light conversion efficiency and FWHM compared to the light conversion ink composition not containing the compound represented by Chemical Formula 9. Furthermore, the light conversion ink composition of the examples containing the compound represented by Chemical Formula 9 can be re-ejected after ink ejection and has good droplet straightness, thus indicating excellent ejection performance. Since the nozzle surface is not wetted by the light conversion ink composition even after ink ejection, it can be seen that it has excellent jetting performance. Therefore, it is possible to provide an excellent light conversion ink composition with high color purity in continuous processes.

[0734] Furthermore, the coating film formed by the light conversion ink composition of the example containing more than 0.1% by weight and less than 15% by weight of the compound represented by Chemical Formula 9 based on the total weight of the solid components in the composition has a light conversion efficiency of over 30%, excellent ejection performance, and no nozzle wetting. In contrast, the coating film formed by the light conversion ink composition of the reference examples containing 0.1% by weight and 15% by weight of the compound represented by Chemical Formula 9 based on the total weight of the solid components in the composition has a light conversion efficiency of 25% to 36%, ordinary ejection performance, and some nozzle wetting.

[0735] Therefore, it can be confirmed that the coating film formed by the light conversion ink composition of the embodiment containing more than 0.1% by weight and less than 15% by weight of the compound represented by chemical formula 9 based on the total weight of the solid components in the composition has improved inkjet performance after ink ejection compared with the coating film formed by the light conversion ink composition of the reference example whose content of the compound is not within the above range.

Claims

1. A light-converting ink composition comprising luminescent particles, polymerizable monomers, and additives. The additive contains at least one selected from chemical formulas 1, 6, 7, and 9. The total content of compounds represented by chemical formulas 1, 6, 7, and 9, based on 100% by weight of the total solid components of the light-conversion ink composition, is greater than 0.1% by weight and less than 15% by weight: [Chemical Formula 1] In the chemical formula 1, R a R b and R c Each is independently hydrogen, a substituted or unsubstituted alkyl group having 1 to 5 carbon atoms, or a hydrocarbon group having 2 to 50 carbon atoms containing at least two nitrogen atoms. [Chemical Formula 6] In the chemical formula 6, R 61 and R 62 Each of the following is independently a substituted or unsubstituted alkylene group having 1 to 10 carbon atoms, a substituted or unsubstituted cycloalkylene group having 5 to 10 carbon atoms, a substituted or unsubstituted arylene group having 4 to 20 carbon atoms, a substituted or unsubstituted heteroarylene group having 4 to 20 carbon atoms, a substituted or unsubstituted arylalkylene group having 6 to 30 carbon atoms, or a substituted or unsubstituted heteroarylalkylene group having 6 to 30 carbon atoms; R 63 The substituted or unsubstituted alkylene group having 1 to 10 carbon atoms, the substituted or unsubstituted alkenyl group having 1 to 10 carbon atoms, the substituted or unsubstituted cycloalkylene group having 5 to 10 carbon atoms, the substituted or unsubstituted alkyleneoxy group having 1 to 10 carbon atoms, or the substituted or unsubstituted alkylthiol group having 1 to 10 carbon atoms. R 64 and R 65 Each is independently hydrogen, or a substituted or unsubstituted alkyl group having 1 to 10 carbon atoms; X6 and Y6 are each independently hydrogen or hydroxyl groups. [Chemical Formula 7] In the chemical formula 7, R 71 Aryl groups, with or without substituted carbon atoms, having 6 to 20 carbon atoms; R 72 For substituted or unsubstituted aryl groups having 6 to 20 carbon atoms ; R 73 A substituted or unsubstituted aryl group having 6 to 20 carbon atoms; R 74 It is a substituted or unsubstituted aryl or alkyl group having 6 to 20 carbon atoms. [Chemical Formula 9] In the chemical formula 9, R 91 and R 92 Each of the following is independently a single bond, an alkoxyalkylene group having 1 to 10 carbon atoms, a divalent or trivalent amino group having 1 to 10 carbon atoms, an arylene group having 1 to 10 carbon atoms, or a substituted or unsubstituted alkylene group having 1 to 10 carbon atoms; A9 is a substituted or unsubstituted aryl group having 5 to 20 carbon atoms, a substituted or unsubstituted arylene group having 5 to 20 carbon atoms, a substituted or unsubstituted heteroaryl group having 5 to 20 carbon atoms, a substituted or unsubstituted heteroarylene group having 5 to 20 carbon atoms, or a substituted or unsubstituted heterocyclic alkylene group having 4 to 20 carbon atoms. n9 is between 0 and 1.

2. The light-converting ink composition of claim 1, wherein the chemical formula 1 comprises at least one compound represented by the following chemical formulas 2 to 5: [Chemical Formula 2] In the chemical formula 2, R1, R2, R4, R6 and R7 are each independently hydrogen, or substituted or unsubstituted alkyl groups having 1 to 5 carbon atoms; R3 and R5 are each independently a substituted or unsubstituted alkylene group having 1 to 5 carbon atoms. [Chemical Formula 3] In the chemical formula 3, R8, R9, R 11 R 13 R 15 and R 16 Each is independently hydrogen, or a substituted or unsubstituted alkyl group having 1 to 5 carbon atoms. R 10 R 12 and R 14 Each is independently a substituted or unsubstituted alkylene group having 1 to 5 carbon atoms. [Chemical Formula 4] In the chemical formula 4, R 17 R 18 R 21 R 22 R 24 and R 25 Each is independently hydrogen, or a substituted or unsubstituted alkyl group having 1 to 5 carbon atoms; R 19 R 20 and R 23 Each is independently a substituted or unsubstituted alkylene group having 1 to 5 carbon atoms. [Chemical Formula 5] In the chemical formula 5, R 17 R 18 R 20 R 22 R 24 R 26 and R 27 Each is independently hydrogen, or a substituted or unsubstituted alkyl group having 1 to 5 carbon atoms. R 19 R 21 R 23 and R 25 Each is independently a substituted or unsubstituted alkylene group having 1 to 5 carbon atoms.

3. The light conversion ink composition of claim 1, wherein the polymerizable monomer comprises a compound represented by the following chemical formula 10: [Chemical Formula 10] In the chemical formula 10, R 281 It is an alkylene, phenylene, or cycloalkylene having 1 to 20 carbon atoms; R 291 Each can be either hydrogen or methyl; m 10 It is an integer from 1 to 15.

4. The light conversion ink composition of claim 3, wherein the polymerizable monomer further comprises a monofunctional monomer or a polyfunctional monomer having at least three unsaturated double bonds.

5. The photoconversion ink composition of claim 3, wherein the compound represented by the chemical formula 10 comprises at least one selected from the group consisting of 1,6-hexanediol diacrylate, polyethylene glycol diacrylate, 2-hydroxy-3-methacryloylpropyl acrylate, 1,9-bisacryloyloxynonane, and tripropylene glycol diacrylate.

6. The light conversion ink composition of claim 1 further comprises at least one selected from the group consisting of scattering particles, photopolymerization initiators, additives, and solvents.

7. The light-converting ink composition of claim 6, wherein the scattering particles comprise at least one selected from the group consisting of Al2O3, SiO2, ZnO, ZrO2, BaTiO3, TiO2, Ta2O5, Ti3O5, ITO, IZO, ATO, ZnO-Al, Nb2O3, SnO, and MgO.

8. The light conversion ink composition of claim 1 further comprises an antioxidant.

9. The light conversion ink composition of claim 8, wherein the antioxidant comprises at least one selected from phenolic compounds, phosphorus compounds, and sulfur compounds.

10. The light conversion ink composition of claim 1, wherein the light conversion ink composition is a solvent-free, non-solvent type.

11. A light conversion laminate substrate, said light conversion laminate substrate being manufactured using the light conversion ink composition as described in any one of claims 1 to 10.

12. A backlight unit comprising the light conversion laminate substrate as described in claim 11.

13. A light-converting pixel substrate, said light-converting pixel substrate being manufactured using the light-converting ink composition as described in any one of claims 1 to 10.

14. An image display device, comprising the backlight unit as described in claim 12.

15. An image display device comprising the light conversion pixel substrate as described in claim 13.

Images