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

Abstract

The present application relates to a light-converting ink composition including a light-emitting particle, a polymerizable monomer, and an additive having a specific structure, a light-converting layered substrate manufactured using the light-converting ink composition, and a backlight unit including the light-converting layered substrate, a light-converting pixel substrate manufactured using the light-converting ink composition, and an image display device including the backlight unit or the light-converting pixel substrate.

Description

Technical Field

[0001] The present invention relates to a light conversion ink composition; a light conversion multilayer substrate manufactured using the light conversion ink composition and a backlight unit including the light conversion multilayer substrate; a light conversion pixel substrate manufactured using the light conversion ink composition; and an image display device including the backlight unit or the light conversion pixel substrate. 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 device 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 light-emitting 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] In this regard, Korean Patent Application Publication No. 10-2019-0119457 discloses a quantum dot comprising a core containing Ag, In, Ga, and S and a ZnS shell, which can be used as a quantum dot in a light conversion ink composition. However, the light conversion ink composition containing this quantum dot has poor ejection continuity and ejection stability, resulting in poor light conversion efficiency, blue light absorbance, lightfastness, and film hardness of the coating, leading to deterioration of optical properties. Moreover, there is also the problem of optical property deterioration due to the aggregation of scattering particles.

[0007] Therefore, there is a need to develop a conversion ink composition that can form a light conversion laminate substrate and a light conversion pixel substrate with excellent light conversion efficiency, lightfastness, blue light absorbance, and coating hardness, without the agglomeration of scattering particles, and also has excellent ejection continuity and ejection stability.

[0008] [Existing technical documents]

[0009] [Patent Literature]

[0010] (Patent Document 1) Korean Patent Application Publication No. 10-2019-0119457 Summary of the Invention

[0011] Technical issues

[0012] The present invention aims to improve the above-mentioned problems of the prior art. The purpose of the present invention is to provide a light conversion ink composition that has excellent light conversion properties, lightfastness and coating hardness, and excellent ejection continuity and ejection stability in inkjet processes.

[0013] Furthermore, the present invention also aims to provide a light conversion laminate substrate and a light conversion pixel substrate manufactured using the light conversion ink composition; a backlight unit including the light conversion laminate substrate; and an image display device including the backlight unit or the light conversion pixel substrate.

[0014] However, the technical problems to be solved by this application are not limited to the above-mentioned technical problems. Those skilled in the art can clearly understand other unmentioned technical problems from the following description.

[0015] Technical solution

[0016] To achieve the above objectives, the present invention provides a light-converting ink composition comprising luminescent particles, polymerizable monomers, and additives, wherein the additives include at least one selected from the following chemical formulas 1 to 4:

[0017] [Chemical Formula 1]

[0018]

[0019] In chemical formula 1, R 11 It is hydrogen or methyl; R 12 It is a straight bond or an alkylene group having 1 to 30 carbon atoms; R 13 It is an alkylene group having 1 to 30 carbon atoms, an alkenyl group having 2 to 30 carbon atoms, a cycloalkylene group having 3 to 30 carbon atoms, a heterocyclic alkylene group having 3 to 30 carbon atoms, an alkoxy group having 1 to 30 carbon atoms, an alkyl ester group having 2 to 31 carbon atoms, an aryl group having 5 to 30 carbon atoms, or an arylalkylene group having 6 to 30 carbon atoms; n1 is an integer from 0 to 100, and is directly bonded when n1 is 0.

[0020] [Chemical Formula 2]

[0021]

[0022] In chemical formula 2, R 21 and R 22 Each is independently a divalent to tetravalent hydrocarbon group having 1 to 10 carbon atoms; R 23 To R 26 Each is independently hydrogen, substituted or unsubstituted alkyl, thiol group, or [other compounds] having 1 to 5 carbon atoms. R 27 A substituted or unsubstituted alkylene group having 1 to 5 carbon atoms; n2 is an integer from 1 to 5, and when n2 is 2 or more, multiple R 22 R 25 R 26 They can each be independent and different from each other.

[0023] [Chemical Formula 3]

[0024]

[0025] In chemical formula 3, R 28 and R 29 Each can be independently either hydrogen or methyl; m2 is an integer from 1 to 3, and when m2 is greater than 2, multiple R... 29 They can be different from each other.

[0026] [Chemical Formula 4]

[0027]

[0028] In chemical formula 4, R 41 X4 is hydrogen or methyl; X4 is O or -NH-; R 43 It is a straight bond or an alkylene group having 1 to 10 carbon atoms; R 44 and R 45 Each is independently hydrogen, an alkyl, allyl, or cycloalkyl group having 1 to 20 carbon atoms; R42 For substituted or unsubstituted alkylene, arylene, alkylarylene, or alkylene groups having 1 to 20 carbon atoms or Where R 46 R 48 R 49 R 410 R 411 R 413 and R 414 Each is independently a substituted or unsubstituted alkylene group having 1 to 10 carbon atoms, R 47 and R 412 Each is independently hydrogen, or a substituted or unsubstituted alkyl group having 1 to 10 carbon atoms, and l4, m4 and n4 are integers from 1 to 3.

[0029] Furthermore, the present invention provides a light conversion laminate substrate manufactured using the light conversion ink composition and a backlight unit including the light conversion laminate substrate.

[0030] Furthermore, the present invention provides a light conversion pixel substrate manufactured using the light conversion ink composition.

[0031] Furthermore, the present invention provides an image display device including the backlight unit or the light conversion pixel substrate.

[0032] Invention Effects

[0033] Compared with existing light conversion ink compositions, the light conversion ink composition according to the present invention can improve light conversion properties.

[0034] Furthermore, compared with existing light conversion ink compositions, the light conversion ink composition according to the present invention can improve blue light absorption.

[0035] Furthermore, compared to existing light-conversion ink compositions, the light-conversion ink composition according to the present invention can improve the hardness of the coating film.

[0036] Furthermore, compared with existing light conversion ink compositions, the light conversion ink composition according to the present invention can improve lightfastness.

[0037] Furthermore, compared with existing light conversion ink compositions, the light conversion ink composition according to the present invention can improve the ejection continuity and ejection stability in inkjet processes. Detailed Implementation

[0038] The present invention provides a light conversion ink composition, a light conversion multilayer substrate manufactured using the light conversion ink composition, a backlight unit including the light conversion multilayer substrate, a light conversion pixel substrate manufactured using the light conversion ink composition, and an image display device including the backlight unit or the light conversion pixel substrate. The light conversion ink composition achieves excellent light conversion efficiency, lightfastness, blue light absorbance, coating hardness, ejection continuity, and ejection stability by including light-emitting particles, polymerizable monomers, and compounds represented by specific chemical formulas as additives.

[0039] Specifically, the light conversion ink composition of the present invention improves the absorption of blue light source by including light-emitting particles, polymerizable monomers and compounds with specific structures as additives, thereby improving light conversion efficiency, improving the continuity and stability of inkjet output, and enabling the manufacture of light conversion laminate substrates or light conversion pixel substrates with excellent lightfastness and coating hardness.

[0040] [Chemical Formula 1]

[0041]

[0042] In chemical formula 1, R 11 It is hydrogen or methyl; R 12 It is a straight bond or an alkylene group having 1 to 30 carbon atoms; R 13 It is an alkylene group having 1 to 30 carbon atoms, an alkenyl group having 2 to 30 carbon atoms, a cycloalkylene group having 3 to 30 carbon atoms, a heterocyclic alkylene group having 3 to 30 carbon atoms, an alkoxy group having 1 to 30 carbon atoms, an alkyl ester group having 2 to 31 carbon atoms, an aryl group having 5 to 30 carbon atoms, or an arylalkylene group having 6 to 30 carbon atoms; n1 is an integer from 0 to 100, and is directly bonded when n1 is 0.

[0043] [Chemical Formula 2]

[0044]

[0045] In chemical formula 2, R 21 and R 22 Each is independently a divalent to tetravalent hydrocarbon group having 1 to 10 carbon atoms; R 23 To R 26 Each is independently hydrogen, substituted or unsubstituted alkyl, thiol group, or [other compounds] having 1 to 5 carbon atoms. R 27 A substituted or unsubstituted alkylene group having 1 to 5 carbon atoms; n2 is an integer from 1 to 5, and when n2 is 2 or more, multiple R 22 R 25 R 26They can each be independent and different from each other.

[0046] [Chemical Formula 3]

[0047]

[0048] In chemical formula 3, R 28 and R 29 Each can be independently either hydrogen or methyl; m2 is an integer from 1 to 3, and when m2 is greater than 2, multiple R... 29 They can be different from each other.

[0049] [Chemical Formula 4]

[0050]

[0051] In chemical formula 4, R 41 X4 is hydrogen or methyl; X4 is O or -NH-; R 43 It is a straight bond or an alkylene group having 1 to 10 carbon atoms; R 44 and R 45 Each is independently hydrogen, an alkyl, allyl, or cycloalkyl group having 1 to 20 carbon atoms; R 42 For substituted or unsubstituted alkylene, arylene, alkylarylene, or alkylene groups having 1 to 20 carbon atoms or Where R 46 R 48 R 49 R 410 R 411 R 413 and R 414 Each is independently a substituted or unsubstituted alkylene group having 1 to 10 carbon atoms, R 47 and R 412 Each is independently hydrogen, or a substituted or unsubstituted alkyl group having 1 to 10 carbon atoms, and l4, m4 and n4 are integers from 1 to 3.

[0052] The present invention will now be described in detail.

[0053] <Photoconversion ink composition>

[0054] The light-conversion ink composition of the present invention comprises luminescent particles, polymerizable monomers and compounds represented by chemical formulas 1 to 4, and may, if desired, also comprise at least one of a compound represented by chemical formula 6, scattering particles, a photopolymerization initiator, an additive and a solvent.

[0055] luminescent particles

[0056] Luminescent particles can, for example, 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.

[0057] In this invention, the luminescent particles contain semiconductor materials, such as quantum dots.

[0058] In one embodiment of the invention, the quantum dot has a core-shell structure, comprising a core and a shell covering at least a portion of the core.

[0059] There are no particular restrictions on quantum dots as long as they are quantum dot particles that can emit light when excited by light or electricity. For example, they can be selected from the group consisting of group II-VI semiconductor compounds, group III-V semiconductor compounds, group IV-VI semiconductor compounds, group IV elements or compounds containing them, and combinations thereof, and they can be used alone or in combination of two or more.

[0060] For example, group II-VI semiconductor compounds can be selected from the group consisting of binary, ternary, and quaternary compounds. Binary compounds are selected from the group consisting of CdS, CdSe, CdTe, ZnS, ZnSe, ZnTe, ZnO, HgS, HgSe, HgTe, and mixtures thereof. Ternary compounds are selected from the group consisting of CdSeS, CdSeTe, CdSTe, ZnSeS, ZnSeTe, ZnSTe, HgSeS, HgSeTe, and HgSTe. e, CdZnS, CdZnSe, CdZnTe, CdHgS, CdHgSe, CdHgTe, HgZnS, HgZnSe, HgZnTe and mixtures thereof, wherein the quaternary compound is selected from the group consisting of CdZnSeS, CdZnSeTe, CdZnSTe, CdHgSeS, CdHgSeTe, CdHgSTe, HgZnSeS, HgZnSeTe, HgZnSTe and mixtures thereof, but is not limited thereto.

[0061] III-V semiconductor compounds can be selected from the group consisting of binary, ternary, and quaternary compounds. Binary compounds are selected from the group consisting of GaN, GaP, GaAs, GaSb, AlN, AlP, AlAs, AlSb, InN, InP, InAs, InSb, and mixtures thereof. Ternary compounds are selected from the group consisting of GaNP, GaNAs, GaNSb, GaPAs, GaPSb, AlNP, AlNAs, AlNSb, AlPAs, AlPSb, InNP, InNAs, InNSb, InPAs, InPSb, GaAlNP, and mixtures thereof. Quaternary compounds are selected from the group consisting of GaAlNAs, GaAlNSb, GaAlPAs, GaAlPSb, GaInNP, GaInNAs, GaInNSb, GaInPAs, GaInPSb, InAlNP, InAlNAs, InAlNSb, InAlPAs, InAlPSb, and mixtures thereof, but are not limited thereto.

[0062] IV-VI semiconductor compounds may be at least one selected from the group consisting of binary, ternary, and quaternary compounds, wherein the binary compounds are selected from the group consisting of SnS, SnSe, SnTe, PbS, PbSe, PbTe, and mixtures thereof; the ternary compounds are selected from the group consisting of SnSeS, SnSeTe, SnSTe, PbSeS, PbSeTe, PbSTe, SnPbS, SnPbSe, SnPbTe, and mixtures thereof; and the quaternary compounds are selected from the group consisting of SnPbSSe, SnPbSeTe, SnPbSTe, and mixtures thereof, but are not limited thereto.

[0063] Although there are no restrictions, group IV elements or compounds containing them may be selected from the group consisting of elements and binary compounds, wherein the elements are selected from the group consisting of Si, Ge and mixtures thereof, and the binary compounds are selected from the group consisting of SiC, SiGe and mixtures thereof.

[0064] Quantum dots can be homogeneous single structures, dual structures such as core-shell and gradient structures, or hybrid structures. In this invention, the type of quantum dot is not particularly limited as long as it can emit light under light excitation.

[0065] According to one embodiment, the quantum dot has a core-shell structure, wherein the core may comprise at least one selected from the group consisting of InP, InZnP, InGaP, CdSe, CdS, CdTe, ZnS, ZnSe, ZnTe, CdSeTe, CdZnS, CdSeS, PbSe, PbS, PbTe, AgInZnS, HgS, HgSe, HgTe, GaN, GaP, GaAs, InGaN, InAs, and ZnO, and the shell may comprise at least one selected from ZnS, ZnSe, ZnTe, and ZnO. The core-shell structure may contain at least one of the following: CdS, CdSe, CdTe, CdO, InP, InS, GaP, GaN, GaO, InZnP, InGaP, InGaN, InZnSCdSe, PbS, TiO, SrSe, and HgSe. Preferably, the core-shell structure may contain at least one of the following: InP / ZnS, InP / ZnSe, InP / GaP / ZnS, InP / ZnSe / ZnS, InP / ZnSeTe / ZnS, and InP / MnSe / ZnS.

[0066] According to an exemplary embodiment, the core comprises a quaternary compound of silver (Ag), indium (In), gallium (Ga), and sulfur (S). For example, the core is AgInGaS. Such a core has the advantage of being able to more effectively absorb light from short-wavelength light sources and minimize the light absorption rate of the emitting region, thus excellent light conversion efficiency can be expected even with a small content.

[0067] The shell contains at least two elements selected from In, Ga, and S, and may include, 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. According to exemplary embodiments, examples of core-shell structured quantum dots may include, but are not limited to, AgInGaS / GaS.

[0068] 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.

[0069] 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.

[0070] Wet chemistry is a method of growing particles by placing precursor materials in an organic solvent. During crystal growth, the organic solvent naturally coordinates to 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.

[0071] In this invention, the content of luminescent particles, based on the total weight of solid components in the light-conversion ink composition, 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.

[0072] 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 may result in insufficient components for curing, leading to insufficient coating curing and thus reducing the productivity of post-manufacturing processes and the reliability of the product.

[0073] Compounds represented by chemical formulas 1 to 4

[0074] In one embodiment of the present invention, the light conversion ink composition comprises at least one of the compounds represented by the following chemical formulas 1 to 4.

[0075] [Chemical Formula 1]

[0076]

[0077] In chemical formula 1,

[0078] R 11 It can be hydrogen or methyl;

[0079] R 12 It is a straight bond or an alkylene group having 1 to 30 carbon atoms;

[0080] R 13It is an alkylene group having 1 to 30 carbon atoms, an alkenyl group having 2 to 30 carbon atoms, a cycloalkylene group having 3 to 30 carbon atoms, a heterocyclic alkylene group having 3 to 30 carbon atoms, an alkoxy group having 1 to 30 carbon atoms, an alkyl ester group having 2 to 31 carbon atoms, an aryl group having 5 to 30 carbon atoms, or an arylalkylene group having 6 to 30 carbon atoms;

[0081] n1 is an integer from 0 to 100, and direct bonding occurs when n1 is 0.

[0082] Alkylenes having 1 to 30 carbon atoms refer to straight-chain or branched divalent hydrocarbons having 1 to 30 carbon atoms. Examples include, but are not limited to, methylene, ethylene, n-propyl, isopropylene, n-butylene, isobutylene, n-pentylene, n-hexylene, n-heptylene, n-octyl, and n-nonyl.

[0083] An alkenyl group having 2 to 30 carbon atoms refers to a straight-chain, branched, or cyclic divalent hydrocarbon derived from an olefin having 2 to 30 carbon atoms.

[0084] Cycloalkylene compounds having 3 to 30 carbon atoms refer to monocyclic or fused-ring divalent hydrocarbons having 3 to 30 carbon atoms. Examples include, but are not limited to, cyclopropylene, cyclobutylene, cyclopentylene, and cyclohexylene.

[0085] Heterocyclic alkylene (heteroarylalkylene) having 3 to 30 carbon atoms refers to a cyclic alkylene ring having 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).

[0086] Aromatic hydrocarbons having 5 to 30 carbon atoms refer to monocyclic or polycyclic divalent aromatic hydrocarbons derived from aromatic hydrocarbons having 5 to 30 carbon atoms. Examples include, but are not limited to, phenylene, biphenylene, terphenylene, and naphthylene.

[0087] 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.

[0088] The alkylene, alkenylene, cycloalkylene, heterocycloalkylene, alkyleneoxy, alkylene ester, arylene, or arylalkylene 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, 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, alkoxycarbonyl, carboxyl, carbamoyl, cyano, nitro, etc., but are not limited thereto.

[0089] The compound represented by chemical formula 1 improves the light conversion efficiency, color purity, and uniformity of the coating film formed by the light conversion ink composition, and plays a role in preventing the aggregation of scattering particles when the light conversion ink composition contains scattering particles.

[0090] Specifically, in order to maximize the processability of the ink composition, the compound represented by Formula 1 may be included in the ink composition as a separate component (e.g., in the form of an additive) rather than in the form of surface coordination with the luminescent particles, but is not limited thereto.

[0091] [Chemical Formula 2]

[0092]

[0093] In chemical formula 2,

[0094] R 21 and R 22 Each is independently a divalent to tetravalent hydrocarbon group having 1 to 10 carbon atoms;

[0095] R 23 To R 26 Each is independently hydrogen, substituted or unsubstituted alkyl, thiol group, or [other compounds] having 1 to 5 carbon atoms. R 27 A substituted or unsubstituted alkylene group having 1 to 5 carbon atoms;

[0096] n2 is an integer from 1 to 5, and when n2 is greater than 2, multiple R 22 R 25 R 26 They can each be independent and different from each other.

[0097] [Chemical Formula 3]

[0098]

[0099] In chemical formula 3,

[0100] R 28 and R 29 Each can be either hydrogen or methyl;

[0101] m2 is an integer from 1 to 3, and when m2 is greater than 2, multiple R 29 They can be different from each other.

[0102] Alkyl groups having 1 to 5 carbon atoms refer to straight-chain or branched monovalent hydrocarbons having 1 to 10 carbon atoms, while alkylene groups having 1 to 5 carbon atoms or 1 to 10 carbon atoms refer to straight-chain or branched divalent hydrocarbons having 1 to 5 carbon atoms or 1 to 10 carbon atoms. Examples include, but are not limited to, methyl (methylene), ethyl (ethylene), n-propyl (n-propylene), isopropyl (isopropylene), n-butyl (n-butylene), isobutyl (isobutylene), n-pentyl (n-pentylene), n-hexyl (n-hexylene), n-heptyl (n-heptylene), n-octyl (n-octylene), and n-nonyl (n-nonylene).

[0103] The alkyl and / or alkylene groups 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, 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, alkoxycarbonyl, carboxyl, carbamoyl, cyano, nitro, etc., but preferably the terminal is substituted with a thiol group.

[0104] Additives of Formula 2 and / or Formula 3 can improve the light conversion efficiency, blue light absorbance, and coating hardness of the coating film formed from the light conversion ink composition. In particular, in the case of compositions containing AIGS-type quantum dots (quaternary compounds containing silver (Ag), indium (In), gallium (Ga), and sulfur (S) in the core), problems may arise in the ink preparation process due to oxygen and moisture leading to a decrease in light efficiency. However, by using the thiols of Formula 1 and Formula 2 of the present invention, the quantum dots can be protected from external environmental influences, thereby resulting in excellent light efficiency and absorbance.

[0105]

[0106] In chemical formula 4,

[0107] R 41 It can be hydrogen or methyl;

[0108] X4 is either O or -NH-;

[0109] R 43 It is a straight bond or an alkylene group having 1 to 10 carbon atoms;

[0110] R 44 and R 45 Each is independently hydrogen, an alkyl group having 1 to 20 carbon atoms, an allyl group, or a cycloalkyl group;

[0111] R 42 For substituted or unsubstituted alkylene, arylene, alkylarylene, or alkylene groups having 1 to 20 carbon atoms Where R 46 R 48 R 49 R 410 R 411 R 413 and R 414 Each is independently a substituted or unsubstituted alkylene group having 1 to 10 carbon atoms, R 47 and R 412 Each is independently hydrogen, or a substituted or unsubstituted alkyl group having 1 to 10 carbon atoms, and l4, m4 and n4 are integers from 1 to 3.

[0112] In this invention, "substitution" can refer to substitution by an alkyl, allyl or cycloalkyl group having 1 to 20 carbon atoms, an alkylene group having 1 to 20 carbon atoms, an arylene group or an alkylarylene group having 1 to 20 carbon atoms, but is not limited thereto.

[0113] The light conversion ink composition of the present invention protects the quantum dot surface from external oxygen and moisture by using an amine of chemical formula 4 and a photopolymerizable structure, thus improving not only light conversion efficiency and lightfastness, but also extrusion stability.

[0114] The compounds represented by chemical formula 1 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 1-1 to 1-17.

[0115] [Chemical Formula 1-1]

[0116]

[0117] [Chemical Formula 1-2]

[0118]

[0119] [Chemical Formulas 1-3]

[0120]

[0121] [Chemical Formulas 1-4]

[0122]

[0123] [Chemical Formulas 1-5]

[0124]

[0125] [Chemical Formulas 1-6]

[0126]

[0127] [Chemical Formulas 1-7]

[0128]

[0129] [Chemical Formulas 1-8]

[0130]

[0131] [Chemical Formulas 1-9]

[0132]

[0133] [Chemical Formulas 1-10]

[0134]

[0135] [Chemical Formula 1-11]

[0136]

[0137] [Chemical Formula 1-12]

[0138]

[0139] [Chemical Formula 1-13]

[0140]

[0141] [Chemical Formula 1-14]

[0142]

[0143] [Chemical Formula 1-15]

[0144]

[0145] [Chemical Formula 1-16]

[0146]

[0147] [Chemical Formula 1-17]

[0148]

[0149] Specifically, the compounds represented by chemical formula 2 may include, but are not limited to, compounds represented by the following chemical formulas 2-1 to 2-13.

[0150] [Chemical Formula 2-1]

[0151]

[0152] 2,2'-Thiobis(ethane-1-thiol)

[0153] [Chemical Formula 2-2]

[0154]

[0155] 2,2'-(ethane-1,2-diylbis(thioalkyldiyl))bis(ethane-1-thiol)

[0156] [Chemical Formula 2-3]

[0157]

[0158] 2,2'-((3-mercaptopropane-1,2-diyl)bis(thionidyl))bis(ethane-1-thiol)

[0159] [Chemical Formula 2-4]

[0160]

[0161] (propane-1,1,3,3-tetramethyltetra(thionidyl))tetramethylthiol

[0162] [Chemical Formula 2-5]

[0163]

[0164] 2,2'-((3-mercaptopropane-1,2-diyl)bis(thionidyl))bis(propane-1-thiol) [Chemical Formula 2-6]

[0165]

[0166] 3,3'-Thiobis(propane-1,2-dithiol)

[0167] [Chemical Formula 2-7]

[0168]

[0169] 3,3'-Thiobis(2-((1-mercaptopropane-2-yl)thio)propane-1-thiol)

[0170] [Chemical Formula 2-8]

[0171]

[0172] 2,2'-((thiobis(ethane-2,1-diyl))bis(thioalkyldiyl))bis(ethane-1-thiol) [Chemical Formula 2-9]

[0173]

[0174] 3,3'-Thiobis(2-((2-mercaptoethyl)thio)propane-1-thiol)

[0175] [Chemical Formula 2-10]

[0176]

[0177] 2,2'-Thiobis(3-((2-mercaptoethyl)thio)propane-1-thiol)

[0178] [Chemical Formula 2-11]

[0179]

[0180] 2-((3-mercapto-2-((2-mercaptoethyl)thio)propyl)thio)-3-((2-mercaptoethyl)thio)propane-1-thiol

[0181] [Chemical Formula 2-12]

[0182]

[0183] [Chemical Formula 2-13]

[0184]

[0185] 3,6,10,14,17-pentathane-1,8,12,19-tetrathiol

[0186] In addition, specifically, the compound represented by chemical formula 2 may include, but is not limited to, compounds represented by the following chemical formulas 3-1 to 3-5.

[0187] [Chemical Formula 3-1]

[0188]

[0189] (1,4-Dithionecyclohexane-2,3-diyl)dimethylthiol

[0190] [Chemical Formula 3-2]

[0191]

[0192] (1,4-Dithioneheptan-2,3-diyl)dimethylthiol

[0193] [Chemical Formula 3-3]

[0194]

[0195] (5-Methyl-1,4-dithionecyclohexane-2,3-diyl)dimethylthiol

[0196] [Chemical Formula 3-4]

[0197]

[0198] (1,4-Dithionecyclooctane-2,3-diyl)dimethylthiol

[0199] [Chemical Formula 3-5]

[0200]

[0201] (5,6-Dimethyl-1,4-dithiacyclohexane-2,3-diyl)dimethylthiol

[0202] The compounds represented by chemical formula 4 may be suitably selected without affecting the purpose of the invention, but preferably include at least one of the compounds represented by chemical formulas 4-1 to 4-12 as amine acrylates / acrylamides.

[0203] [Chemical Formula 4-1]

[0204]

[0205] [Chemical Formula 4-2]

[0206]

[0207] [Chemical Formula 4-3]

[0208]

[0209] [Chemical Formula 4-4]

[0210]

[0211] [Chemical Formula 4-5]

[0212]

[0213] [Chemical Formula 4-6]

[0214]

[0215] [Chemical Formula 4-7]

[0216]

[0217] [Chemical Formula 4-8]

[0218]

[0219] [Chemical Formula 4-9]

[0220]

[0221] [Chemical Formula 4-10]

[0222]

[0223] [Chemical Formula 4-11]

[0224]

[0225] [Chemical Formula 4-12]

[0226]

[0227] The compound represented by chemical formula 4 can improve the light conversion efficiency, lightfastness and extrusion stability of light conversion ink compositions.

[0228] Furthermore, in one embodiment of the present invention, in addition to the form of an additive, compounds represented by chemical formulas 1 to 4 may also be included in the composition as organic ligands that coordinate with the surface of the luminescent particles. When compounds represented by chemical formulas 1 to 4 coordinate with the surface of the luminescent particles as organic ligands, they can stabilize the luminescent particles and, by protecting the surface of the luminescent particles, exhibit not only superior oxidative stability compared to existing luminescent particles, but also, due to their excellent dispersibility in monomers, improve optical properties.

[0229] In one embodiment of the present invention, compounds represented by chemical formulas 1 to 4 are included in the light conversion ink composition both as additives as separate components of the ink composition and as organic ligands that are surface-coordinated with the luminescent particles.

[0230] Based on the total weight of the solid components in the light conversion ink composition, the content of the compound represented by Formula 1 can be greater than 0.1% by weight and less than 20% by weight. When the content of the compound represented by Formula 1 is within the above range, the light conversion efficiency and coating uniformity can be further improved, and when the light conversion ink composition contains scattering particles, the aggregation of scattering particles can be further suppressed, thereby improving the ejection stability in the inkjet process.

[0231] polymerizable monomers

[0232] In one embodiment of the present invention, the light conversion ink composition comprises a polymerizable monomer.

[0233] Polymerizable monomers may contain compounds represented by the following chemical formula 5.

[0234] [Chemical Formula 5]

[0235]

[0236] In chemical formula 5,

[0237] R 51 The substituted or unsubstituted alkylene group having 1 to 20 carbon atoms, the substituted or unsubstituted cycloalkylene group having 3 to 10 carbon atoms, the substituted or unsubstituted arylene group having 5 to 20 carbon atoms, the substituted or unsubstituted heteroarylene group having 2 to 15 carbon atoms, the substituted or unsubstituted arylalkylene group having 6 to 30 carbon atoms, the substituted or unsubstituted heteroarylalkylene group having 3 to 30 carbon atoms, the substituted or unsubstituted alkenylene group having 2 to 10 carbon atoms, or the substituted or unsubstituted ynylene group having 2 to 10 carbon atoms;

[0238] R 52 and R 53 Each can be independently a hydrogen atom or a methyl group;

[0239] m5 is an integer from 1 to 15.

[0240] Alkylene, cycloalkylene, arylene, arylalkylene, heteroarylalkylene, and alkenylene are substantially the same as those described above for compounds represented by Formula 1.

[0241] A heteroaryl 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 oxygen (O), nitrogen (N), or sulfur (S). Examples include thiopheneyl, furanyl, pyrrolyl, imidazolyl, thiazolyl, oxazolyl, oxadiazolyl, pyridyl, bipyridyl, pyrimidinyl, triazinyl, triazolyl, acridineyl, pyridazinyl, pyrazinyl, quinolinyl, quinazolinyl, quinoxalinyl, phthalazinyl, pyridopyrimidinyl, pyridopyrazinyl, pyrazinopyrazinyl, isoquinolinyl, indolyl, carbazoleyl, benzoxazolyl, benzoimidazolyl, benzothiazolyl, benzocarbazoleyl, benzothiopheneyl, dibenzothiopheneyl, benzofuranyl, phenanthrolinel (p henanthroline), 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.

[0242] Alynyl groups with 2 to 10 carbon atoms refer to straight-chain, branched, or cyclic divalent hydrocarbons derived from alkynes with 2 to 10 carbon atoms.

[0243] In one embodiment, R 51 It can be an alkylene group having 1 to 20 carbon atoms, preferably an alkylene group having 2 to 16 carbon atoms. When R 51 When the alkylene group has 1 to 20 carbon atoms, the light conversion ink composition of the present invention exhibits excellent dispersion of luminescent particles even under solvent-free conditions, thereby improving sprayability and increasing coating hardness and thickness uniformity.

[0244] In one embodiment, as described above, m5 can be an integer from 1 to 15, preferably an integer from 1 to 5. If it exceeds the above range, it may result in higher viscosity, leading to deterioration of dispersibility.

[0245] The compound represented by chemical formula 5 may be suitably selected without affecting the purpose of the invention, but may include at least one selected from the group consisting of 1,6-hexanediol diacrylate, polyethylene glycol diacrylate, 2-hydroxy-3-methacryloylpropyl acrylate, 1,9-bisacryloyloxynonane, tripropylene glycol diacrylate, etc.

[0246] The compound represented by chemical formula 5 improves the dispersibility of luminescent particles, enabling the achievement of low-viscosity light-conversion ink compositions of 80 cP or lower without solvents. Therefore, the light-conversion ink compositions according to the present invention can be effectively used to manufacture light-conversion laminated substrates using inkjet printing.

[0247] In addition to the polymerizable monomers represented by Formula 5, the photoconversion ink compositions of the present invention may also contain polymerizable compounds commonly used in the art, without departing from the scope of the invention. Examples include monofunctional monomers, difunctional monomers, and other multifunctional monomers, with difunctional monomers being preferred.

[0248] 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.

[0249] There are no particular restrictions on the types of bifunctional monomers; examples may include bis(acryloyloxyethyl) ether of bisphenol A.

[0250] 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.

[0251] 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.

[0252] Based on the total weight of solid components in the light-conversion ink composition, the content of polymerizable monomers can be from 30 to 95% by weight, preferably from 40 to 90% by weight. When the content of polymerizable monomers is within the above range, it has advantages in terms of pixel 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 may cause insufficient content of light-emitting particles, resulting in a decrease in light efficiency. Therefore, a content within the above range is preferred.

[0253] Compounds represented by chemical formula 6

[0254] The light conversion ink composition according to the present invention may also contain a compound represented by chemical formula 6.

[0255] [Chemical Formula 6]

[0256]

[0257] In chemical formula 6,

[0258] Z represents 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.

[0259] R 67 and R 68 Each is independently a straight-bonded, substituted or unsubstituted alkylene group having 1 to 30 carbon atoms, -OR 69 -、-OC(=O)R 610 -、-(OCH2CH2) p - or -(OCH2CH2CH2) q -;

[0260] Q1 and Q2 can each be a straight bond, an oxygen atom, a sulfur atom, or -NH-;

[0261] D represents an oxygen atom, a sulfur atom, or is equal to NH;

[0262] R 69 A substituted or unsubstituted alkylene group having 1 to 30 carbon atoms;

[0263] R 610 A substituted or unsubstituted alkylene group having 4 to 30 carbon atoms;

[0264] p and q are each independent integers from 1 to 150.

[0265] The compounds represented by chemical formula 3 may be suitably selected without affecting the purpose of the invention, but preferably include at least one of the compounds represented by chemical formulas 3-1 to 3-7.

[0266] [Chemical Formula 6-1]

[0267]

[0268] [Chemical Formula 6-2]

[0269]

[0270] [Chemical Formula 6-3]

[0271]

[0272] [Chemical Formula 6-4]

[0273]

[0274] [Chemical Formula 6-5]

[0275]

[0276] [Chemical Formula 6-6]

[0277]

[0278] [Chemical Formulas 6-7]

[0279]

[0280] The compound represented by chemical formula 6 fully protects the unprotected portion of the shell surface, thus having the advantage of preventing quantum dot oxidation during the thermal process of manufacturing the light conversion laminate substrate, thereby improving light efficiency.

[0281] Based on the total weight of the solid components in the light conversion ink composition, the content of the compound represented by Chemical Formula 6 can be from 0.1% to 15% by weight. When the content of the compound represented by Chemical Formula 6 is within the above range, it is beneficial to the dispersion of scattering particles and the viscosity stability over time, while improving the light efficiency.

[0282] Scattering particles

[0283] The light-converting ink composition according to the present invention may also contain scattering particles.

[0284] 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.

[0285] 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.

[0286] 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.

[0287] 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.

[0288] 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.

[0289] Based on the total weight of the solid components 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, and therefore, the content within the above range is preferred. If the content of scattering particles is lower than the above range, it may be difficult to obtain the required 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 work. Therefore, it is preferable to use it appropriately within the above range.

[0290] Photopolymerization initiator

[0291] The light conversion ink composition according to an embodiment of the present invention may further contain a photopolymerization initiator.

[0292] 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.

[0293] For example, to cure films thicker than 5 μm, oxime compounds or phosphine oxide compounds can be used, thereby ensuring superior physical properties in terms of cured film density and surface roughness.

[0294] 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.

[0295] Specific examples of phosphine oxide compounds may include Darocur TPO and Lucirin TPO from BASF as trimethylbenzoylphenylphosphine oxide.

[0296] Based on the total weight of the solid components in 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 will be improved, and the exposure time will be shortened, thus increasing productivity. Therefore, a content within the above range is preferred. When the content of the photopolymerization initiator is below the above range, insufficient light-based curing will occur, 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 will increase sharply, leading to a problem where the desired luminous intensity cannot be obtained. Therefore, using it within the above range is beneficial for improving the intensity of the pixel portion and the smoothness of the pixel portion surface.

[0297] 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, the photosensitivity is further improved, thereby contributing to increased productivity.

[0298] 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.

[0299] Photopolymerization initiation aids may be appropriately added and used within the scope that does not affect the effects of the present invention.

[0300] additive

[0301] In addition to the above-mentioned components, the light conversion ink composition according to an embodiment of the present invention may further include, as needed, additives such as surfactants, antioxidants, and silane coupling agents.

[0302] 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.

[0303] In one embodiment, the light conversion ink composition of the present invention may include an antioxidant. The antioxidant can prevent oxidation of the light conversion ink composition and the resulting coating to further improve light conversion properties or color purity.

[0304] There are no particular limitations on the antioxidant as long as it can further improve the light conversion properties or color purity of the light conversion ink composition. It can be at least one of antioxidants containing phenolic compounds, phosphorus compounds and sulfur compounds, preferably at least one of antioxidants containing phenolic compounds and phosphorus compounds and antioxidants containing phenolic compounds and sulfur compounds.

[0305] In one embodiment, the photoconversion ink composition of the present invention may contain a silane coupling agent. The silane coupling agent may be added to improve adhesion to the substrate.

[0306] Silane coupling agents can be compounds having at least one organic functional group and at least one hydrolyzable group in one molecule, wherein the hydrolyzable group is an alkoxy group or the like bonded to a silicon atom. Preferably, the silane coupling agent has at least one organic functional group selected from the group consisting of epoxy, (meth)acryloyloxy, mercapto, and amino groups. Here, (meth)acryloyloxy refers to acryloyloxy (CH2=CHCOO-) or methacryloyloxy (CH2=C(CH3)COO-).

[0307] Examples of epoxy-based silane coupling agents may include 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropylmethyldiethoxysilane, 3-glycidoxypropylmethyldiethoxysilane, 3-glycidoxypropyltriethoxysilane, 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, 2-(3,4-epoxycyclohexyl)ethylmethyldiethoxysilane, 2-(3,4-epoxycyclohexyl)ethylmethyldiethoxysilane, 2-(3,4-epoxycyclohexyl)ethyltriethoxysilane, 5,6-epoxyhexyltrimethoxysilane, 5,6-epoxyhexylmethyldiethoxysilane, 5,6-epoxyhexylmethyldiethoxysilane, 5,6-epoxyhexyltriethoxysilane, etc.

[0308] Examples of silane coupling agents having (meth)acryloxy groups may include 3-(meth)acryloxypropyltrimethoxysilane, 3-(meth)acryloxypropylmethyldimethoxysilane, 3-(meth)acryloxypropyltriethoxysilane, 3-(meth)acryloxypropylmethyldiethoxysilane, 3-(meth)acryloxypropyldimethylethoxysilane, 3-(meth)acryloxypropyldimethylmethoxysilane, etc.

[0309] Examples of silane coupling agents having a thiol group may include 3-mercaptopropylmethyldimethoxysilane, 3-mercaptopropyltrimethoxysilane, 3-mercaptopropylmethyldiethoxysilane, and 3-mercaptopropyltriethoxysilane.

[0310] Examples of silane coupling agents containing amino groups may include 3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, N-phenyl-3-aminopropyltrimethoxysilane, N-2-(aminoethyl)-3-aminopropylmethyldimethoxysilane, N-2-(aminoethyl)-3-aminopropylmethyldiethoxysilane, N-2-(aminoethyl)-3-aminopropyltrimethoxysilane, N-2-(aminoethyl)-3-aminopropyltriethoxysilane, 3-(methylamino)propyltrimethoxysilane, 3-(methylamino)propyltriethoxysilane, etc.

[0311] Furthermore, the light-conversion ink composition of the present invention may also contain additives such as ultraviolet absorbers and anti-caking agents, without affecting the effects of the present invention. These additives may be appropriately added and used by those skilled in the art without affecting the effects of the present invention.

[0312] Based on the total weight of the solid components in the light conversion ink composition, the amount of additive can be from 0.01 to 10% by weight, specifically from 0.02 to 8% by weight, and more specifically from 0.03 to 5% by weight, but is not limited thereto. If the additive content is within the above range, the flatness and adhesion of the light conversion ink composition can be improved; therefore, a content within the above range is preferred. If the additive content is below the above range, the expected effects such as flatness or adhesion may be insufficient, while if the additive content is above the above range, the content of luminescent particles or polymerizable monomers will decrease, leading to problems such as decreased luminescence intensity or curing degree of the cured film. Therefore, use within the above range is beneficial for improving the strength of the pixel portion and the flatness or adhesion of the pixel portion surface.

[0313] solvent

[0314] The light conversion ink composition according to an embodiment of the present invention may further contain a solvent, or may be a solvent-free type. When the light conversion ink composition of the present invention contains a solvent, for example, based on the total weight of the light conversion ink composition, the solvent content may be 20% by weight or less.

[0315] Preferably, considering continuous processability, the light conversion ink composition according to an embodiment of the present invention can be a solvent-free type.

[0316] Even in the solvent-free form, the light conversion composition of the present invention still exhibits excellent optical properties and dispersibility of the light-emitting particles due to the inclusion of the aforementioned polymerizable monomers, and can achieve low viscosity, thus resulting in excellent nozzle ejection characteristics of the ink.

[0317] Solvents can be ether or ester solvents, aliphatic saturated hydrocarbon solvents, halogenated hydrocarbon solvents, aromatic solvents, etc. 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 and ethyl cellosolve acetate can also be used. Ethylene glycol alkyl ether acetates such as esters; 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.

[0318] <Light conversion multilayer substrate, backlight unit, and image display device>

[0319] One embodiment of the present invention is a light conversion laminate substrate that absorbs light emitted by 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.

[0320] 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.

[0321] 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.

[0322] The substrate can be a flat substrate, such as a glass substrate, silicon substrate, polycarbonate substrate, polyester substrate, aramid substrate, polyamide-imide substrate, polyimide substrate, Al substrate, and GaAs substrate, but is not limited to these. 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 deposition. When a silicon substrate or the like is used as the substrate, 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.

[0323] 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.

[0324] In order to eject ink from a piezoelectric inkjet head, which is an example of an inkjet printer, and 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.

[0325] 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.

[0326] When applied to a blue light source, the light conversion laminate substrate according to the present invention exhibits excellent light output.

[0327] 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.

[0328] Green light-emitting devices can be green light-emitting diodes (LEDs).

[0329] One embodiment of the present invention relates to a backlight unit, including a light conversion laminate substrate applied to a blue light source.

[0330] The backlight unit may also include common components such as light guide plates and reflectors.

[0331] One embodiment of the present invention relates to an image display device including a backlight unit.

[0332] 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.

[0333] 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.

[0334] 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.

[0335] 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.

[0336] <Experimental Example I>

[0337] A-1 Preparation Example: Synthesis and Dispersion Preparation of AgInGaS / GaS Core-Shell Type Luminescent Particles

[0338] 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 AGS core QDs (quantum dots). 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 AIGS core QDs.

[0339] 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 to 280 °C by increasing the temperature by 2 °C per minute. 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.

[0340] Examples, Reference Examples, and Comparative Examples: Preparation of Light Conversion Ink Compositions

[0341] The light conversion ink composition was prepared by mixing the components according to the compositions shown in Tables 1 and 2 below.

[0342] [Table 1]

[0343]

[0344] [Table 2]

[0345]

[0346] -A-1: AgInGaS / GaS luminescent particle dispersion -B-1: 1,6-hexanediol diacrylate (Shin Nakamura Chemical) -B-2: polyethylene glycol diacrylate (Shin Nakamura Chemical) -C: TiO2 (Huntsman, TR-88, particle size 220nm)

[0347] -D: Diphenyl(2,4,6-trimethylbenzoyl)phosphine oxide (Aldrich)

[0348] -E: SH8400 (Dow Corning Toray Silicone)

[0349] -F-1: Compounds represented by chemical formula 1-1

[0350] [Chemical Formula 1-1]

[0351]

[0352] -F-2: Compounds represented by chemical formula 1-2

[0353] [Chemical Formula 1-2]

[0354]

[0355] -F-3: Compounds represented by chemical formulas 1-5

[0356] [Chemical Formulas 1-5]

[0357]

[0358] -F-4: Compounds represented by chemical formulas 1-7

[0359] [Chemical Formulas 1-7]

[0360]

[0361] -F-5: Compounds represented by chemical formulas 1-8

[0362] [Chemical Formulas 1-8]

[0363]

[0364] -F-6: Compounds represented by chemical formula 1-11

[0365] [Chemical Formula 1-11]

[0366]

[0367] -F-7: Compounds represented by chemical formula 1-13

[0368] [Chemical Formula 1-13]

[0369]

[0370] -F-8: Compounds represented by chemical formula 1-14

[0371] [Chemical Formula 1-14]

[0372]

[0373] -G-1: 3-Aminopropyldimethoxymethylsilane (Gelest Corporation)

[0374] -G-2: 3-Glycidoxypropyltrimethoxysilane (Gelest Corporation)

[0375] -G-3: 3-Acryloyloxypropyltrimethoxysilane (Gelest Corporation)

[0376] -H: Sumilizer-GP (Sumitomo Chemical Co., Ltd.)

[0377] Preparation Example I-1: Preparation of Light Conversion Coating

[0378] 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.

[0379] Experimental Examples I-1 and I-2: Evaluation of Light Conversion Efficiency and Blue Light Absorbance

[0380] 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 and blue light absorbance were measured using a luminance meter (CAS140CT Spectrometer, Instrument Systems). The results are shown in Table 3 below.

[0381] Experimental Example I-2: Evaluation of Coating Hardness

[0382] The curing degree of the light conversion coating prepared above was measured at a high temperature of 150°C using a hardness tester (HM500; Fischer product), and the hardness of the coating was evaluated according to the following evaluation criteria. The results are shown in Table 3 below.

[0383] <Coating Hardness Evaluation Standard>

[0384] ○: Surface hardness is 50 or higher

[0385] △: Surface hardness is 30 or higher and less than 50

[0386] X: Surface hardness less than 30

[0387] Experimental Example I-3: Evaluation of Ejection Continuity

[0388] After the above-prepared light-conversion ink composition was filled into a Unijet inkjet printing machine, the printhead temperature was fixed at 40°C, and the machine was allowed to eject ink for 2 hours to evaluate nozzle clogging and droplet characteristics. Ejection continuity was evaluated according to the following criteria, and the results are shown in Table 3 below.

[0389] <Evaluation Criteria>

[0390] ○: No nozzle clogging, good droplet straight-line performance

[0391] △: No nozzle blockage, but droplet bending occurs.

[0392] X: Nozzle clogged

[0393] Experimental Example I-4: Evaluation of Pattern Delamination

[0394] After the light conversion ink compositions prepared in the examples and comparative examples were sprayed onto the separator substrate by inkjet printing, a 395nm blue LED was used under nitrogen atmosphere at a speed of 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. The light conversion coating was examined using OM (Obstacle Course) to check for pattern delamination at the glass interface; the results are shown in Table 3 below.

[0395] <Evaluation Criteria>

[0396] ○: No pattern delamination occurred.

[0397] △: Pattern delamination occurs, accounting for more than 0% but less than 40% of the entire pattern.

[0398] X: Pattern delamination occurs, accounting for more than 40% but less than 70% of the entire pattern.

[0399] [Table 3]

[0400]

[0401] Referring to Table 3, it can be confirmed that Examples I-1 to I-14 and Reference Examples I-1 and I-2, which meet the composition according to the present invention, all exhibit good or excellent results in the evaluation of light conversion efficiency, blue light absorbance, coating hardness, ejection continuity and pattern delamination. However, in Comparative Examples I-1 and I-2, which do not contain the compound represented by Chemical Formula 1 of the present invention, the coating hardness and ejection continuity are greatly reduced.

[0402] Furthermore, it can be confirmed that in the cases of Examples I-9 to I-11, which also contain a silane leveling agent, superior characteristics were exhibited in the pattern delamination evaluation.

[0403] <Experimental Example II>

[0404] A-1 Preparation Example: Synthesis and Dispersion Preparation of AgInGaS / GaS Core-Shell Type Luminescent Particles

[0405] 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.

[0406] 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 to 280 °C by increasing the temperature by 2 °C per minute. 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.

[0407] Preparation Example 2: Synthesis of Compounds F-1 to F-13

[0408] Compounds F-1 to F-13 were prepared according to known methods, specifically based on the synthetic methods described in 10-2015-0171503, 10-2016-0110987, 10-2016-0110861, 10-2015-0188342, 10-2018-0071309, and 10-2018-0013907.

[0409] Examples and Comparative Examples: Preparation of Light Conversion Ink Compositions

[0410] The light conversion ink composition was prepared by mixing the components according to the compositions shown in Tables 4 and 5 below (unit: wt%).

[0411] [Table 4]

[0412]

[0413] [Table 5]

[0414]

[0415] -A-1: AgInGaS / GaS dispersion

[0416] -B-1: 1,6-Hexanediol diacrylate (Shin Nakamura Chemical Co., Ltd.)

[0417] -B-2: Polyethylene glycol diacrylate (Shin Nakamura Chemical Co., Ltd.)

[0418] -C: TiO2 (Huntsman, TR-88, particle size 220nm)

[0419] -D: Diphenyl(2,4,6-trimethylbenzoyl)phosphine oxide (Aldrich)

[0420] -E:SH8400 (Dow Corning Toray Silicone)

[0421] -F-1: Thiol additive represented by chemical formula 2-1 (2,2'-thiobis(ethane-1-thiol), TCI Corporation)

[0422] [Chemical Formula 2-1]

[0423]

[0424] -F-2: Thiol additive represented by chemical formula 2-3 (2,2'-((3-mercaptopropane-1,2-diyl)bis(thiodiyl))bis(ethane-1-thiol))

[0425] [Chemical Formula 2-3]

[0426]

[0427] -F-3: Thiol additive represented by chemical formula 2-4 ((propane-1,1,3,3-tetramethyltetra(thionidyl))tetramethylthiol)

[0428] [Chemical Formula 2-4]

[0429]

[0430] -F-4: Thiol additive represented by chemical formula 2-6 (3,3'-thiobis(propane-1,2-dithiol))

[0431] [Chemical Formula 2-6]

[0432]

[0433] -F-5: Thiol additive represented by chemical formula 2-9 (3,3'-thiobis(2-((2-mercaptoethyl)thio)propane-1-thiol))

[0434] [Chemical Formula 2-9]

[0435]

[0436] -F-6: Thiol additive represented by chemical formula 2-10 (2,2'-thiobis(3-((2-mercaptoethyl)thio)propane-1-thiol))

[0437] [Chemical Formula 2-10]

[0438]

[0439] -F-7: Thiol additive represented by chemical formula 2-11 (2-((3-mercapto-2-((2-mercaptoethyl)thio)propyl)thio)-3-((2-mercaptoethyl)thio)propane-1-thiol)

[0440] [Chemical Formula 2-11]

[0441]

[0442] -F-8: Thiol additive represented by chemical formula 2-13 (3,6,10,14,17-pentathionechodecane-1,8,12,19-tetrathiol)

[0443] [Chemical Formula 2-13]

[0444]

[0445] -F-9: Thiol additive represented by chemical formula 3-1 ((1,4-dithionecyclohexane-2,3-diyl)dimethylthiol)

[0446] [Chemical Formula 3-1]

[0447]

[0448] -F-10: Thiol additive represented by chemical formula 3-2 ((1,4-dithione-heptane-2,3-diyl)dimethylthiol)

[0449] [Chemical Formula 3-2]

[0450]

[0451] -F-11: Thiol additive represented by chemical formula 3-3 ((5-methyl-1,4-dithiacyclohexane-2,3-diyl)dimethylthiol)

[0452] [Chemical Formula 3-3]

[0453]

[0454] -F-12: Thiol additive represented by chemical formula 3-4 ((1,4-dithionecyclooctane-2,3-diyl)dimethylthiol)

[0455] [Chemical Formula 3-4]

[0456]

[0457] [Chemical Formula 3-5]

[0458]

[0459] -F-14: Ethylene glycol di(3-mercaptopropionate) (Sigma-Aldrich)

[0460] -F-15: 1,8-Octadecyl dithiol (TCI Company)

[0461] -G: Sumilizer-GP (Sumitomo Chemical)

[0462] Experimental Example II-1: Preparation of Light Conversion Coating and Evaluation of Light Conversion Efficiency

[0463] 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.

[0464] 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 and blue absorbance were measured using a luminance meter (CAS140CT Spectrometer, Instrument Systems). The results are shown in Table 6 below.

[0465] Experimental Example II-2: Evaluation of Coating Hardness

[0466] The curing degree of the light conversion coating prepared above was measured at a high temperature of 150°C using a hardness tester (HM500; Fischer product), and the hardness of the coating was evaluated according to the following evaluation criteria. The results are shown in Table 6 below.

[0467] <Coating Hardness Evaluation Standard>

[0468] ○: Surface hardness is 50 or higher

[0469] △: Surface hardness is 30 or higher and less than 50

[0470] X: Surface hardness less than 30

[0471] [Table 6]

[0472] Evaluation results Light conversion efficiency (%) Blue absorbance Coating hardness Example 1 34％ 95.10％ ○ Example 2 34％ 94.80％ ○ Example 3 33％ 95.20％ ○ Example 4 33％ 94.70％ ○ Example 5 34％ 94.90％ ○ Example 6 34％ 95.00％ ○ Example 7 34％ 95.10％ ○ Example 8 33％ 95.20％ ○ Example 9 33％ 94.90％ ○ Example 10 33％ 94.70％ ○ Example 11 34％ 94.80％ ○ Example 12 34％ 95.00％ ○ Example 13 33％ 95.10％ ○ Example 14 30％ 94.10％ ○ Example 15 32％ 95.00％ ○ Example 16 34％ 95.10％ ○ Reference Example 1 28％ 90.00％ △ See Example 2 34％ 95.00％ △ See Example 3 30％ 94.80％ △ Comparative Example 1 24％ 85.10％ X Comparative Example 2 29％ 88％ X Comparative Example 3 28％ 88.5 X

[0473] Based on the above experimental results, it was confirmed that in the examples containing the structures of Chemical Formula 2 and / or Chemical Formula 3 of the present invention as additives, the light conversion efficiency, blue absorbance, and coating hardness were all excellent. Conversely, in Comparative Example II-1, which did not contain the structure of the present invention, and Comparative Examples II-2 and II-3, which contained compounds other than the structures of Chemical Formula 2 or Chemical Formula 3 of the present invention as additives, the results showed that the light conversion efficiency, blue absorbance, and coating hardness were all lower compared to the present invention.

[0474] On the other hand, it can be confirmed that Reference Example II-1, containing 0.1% by weight of the structure of Chemical Formula 2 and / or Chemical Formula 3 of the present invention and Reference Example II-2, containing 20% ​​by weight of the structure of Chemical Formula 2 and / or Chemical Formula 3 of the present invention based on the total weight of the solid components in the light conversion ink composition, generally exhibits excellent performance, but is slightly inferior to the examples, particularly in terms of film hardness. Furthermore, it can be confirmed that Reference Example II-3, containing the thiol compound of the present invention but not the antioxidant, also generally exhibits excellent properties, but is slightly inferior to the examples, particularly in terms of film hardness. Therefore, the composition of this embodiment, which simultaneously contains the thiol compound of Chemical Formula 2 and / or Chemical Formula 3 of the present invention and the antioxidant, has very excellent properties in terms of light conversion efficiency or blue light absorbance and film hardness.

[0475] <Experimental Example III>

[0476] Preparation Example A: Synthesis and Dispersion Preparation of AgInGaS / GaS Core-Shell Type Luminescent Particles

[0477] 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.

[0478] 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 to 280 °C by increasing the temperature by 2 °C per minute. 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.

[0479] E-1 to E-13: Additives

[0480] The additives in the embodiments and comparative examples of the present invention were prepared according to known methods or purchased from manufacturers.

[0481] [Chemical Formula 4-1]

[0482]

[0483] 2-(tert-butylamino)methacrylate, TCI Corporation

[0484] [Chemical Formula 4-2]

[0485]

[0486] 2-(Diethylamino)acrylate, Sigma-Aldrich

[0487] [Chemical Formula 4-3]

[0488]

[0489] 2-(diisopropylamino)methacrylate, TCI Corporation

[0490] [Chemical Formula 4-4]

[0491]

[0492] N-(4-aminobutyl)acrylamide (synthetic example confirmed in the European Journal of Medicinal Chemistry, 2021, Vol. 219, Article No. 113432)

[0493] [Chemical Formula 4-5]

[0494]

[0495] N-(4-azapentyl)acrylamide (synthesized in [Polymer, 2010, Vol. 51, #14, pp. 2998-3005], confirmed by a synthetic example)

[0496] [Chemical Formula 4-6]

[0497]

[0498] 2-((2-(dimethylamino)ethyl)(methyl)amino)ethyl acrylate ([Journal of Organic Chemistry USSR, 1969, Vol. 5, #11, pp. 1893-1898][Zhurnal Organicheskoi Khimii, 1969, Vol. 5, #11, pp. 1947-1952] Synthetic examples confirmed)

[0499] [Chemical Formula 4-7]

[0500]

[0501] N-(2-((2-aminoethyl)(methyl)amino)ethyl)acrylamide (WO2013 / 138783, 2013, A1, synthesis example confirmed)

[0502] [Chemical Formula 4-8]

[0503]

[0504] N-(2-((2-((2-aminoethyl)amino)ethyl)amino)ethyl)acrylamide

[0505] (Colloids and Surfaces A: Phys. Eng. Asp., 2019, Vol. 560, pp. 98-105, synthesis example confirmed)

[0506] [Chemical Formula 4-9]

[0507]

[0508] N-(2-(2-(2-aminoethoxy)ethoxy)ethyl)acrylamide ([Chemical Communications, 2008, #11, pp. 1317-1319] confirmed by the synthetic example)

[0509] [Chemical Formula 4-10]

[0510]

[0511] N-(2-(2-(2-(2-aminoethoxy)ethoxy)ethoxy)ethyl)acrylamide (CN104926678, 2017, B, synthesis example confirmed)

[0512] [Chemical Formula 4-11]

[0513]

[0514] 2-((2-(2-(dimethylamino)ethoxy)ethyl)(methyl)amino)ethyl acrylate (KR2015 / 141448, 2015, A, synthesis example confirmed)

[0515] [Chemical Formula 4-12]

[0516]

[0517] 2,8,14-Trimethyl-5,11-dioxa-2,8,14-triazahexadecane-16-ylacrylate (KR2015 / 141448, 2015, A, synthesis example confirmed)

[0518] Examples and Comparative Examples: Preparation of Light Conversion Ink Compositions

[0519] The light conversion ink composition was prepared by mixing the components according to the composition shown in Tables 7 and 8 below (unit: wt%).

[0520] [Table 7]

[0521]

[0522] [Table 8]

[0523]

[0524] -A: AgInGaS / GaS QD 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)

[0525] -D: Diphenyl(2,4,6-trimethylbenzoyl)phosphine oxide (Aldrich)

[0526] -E-1: SH8400 (Dow Corning Toray Silicone)

[0527] -E-2: Additive with chemical formula 4-1

[0528] -E-3: Additive with chemical formula 4-2

[0529] -E-4: Additive with chemical formula 4-3

[0530] -E-5: Additive with chemical formula 4-4

[0531] -E-6: Additive with chemical formula 4-5

[0532] -E-7: Additive with chemical formula 4-6

[0533] -E-8: Additive with chemical formula 4-7

[0534] -E-9: Additive with chemical formula 4-8

[0535] -E-10: Additive with chemical formula 4-9

[0536] -E-11: Additive with chemical formula 4-10

[0537] -E-12: Additive with chemical formula 4-11

[0538] -E-13: Isodecyl acrylate (TCI Company)

[0539] -F-1: Sumilizer-GP (Sumitomo Chemical)

[0540] Experimental Example

[0541] 1. Preparation of light conversion coating and measurement of light conversion efficiency

[0542] 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 and then heating on a hot plate at 180°C for 30 minutes under nitrogen atmosphere.

[0543] 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). The measurement results are shown in Table 9 below.

[0544] 2. Lightfastness evaluation

[0545] The light conversion coating prepared above was left to stand for 1 hour at a blue light source (XLamp XR-E LED, Royal blue 450, Cree). The lightfastness was evaluated by confirming the retention rate (%) relative to the initial light conversion efficiency. The results are shown in Table 9 below.

[0546] 3. Discharge stability

[0547] Each light-conversion ink composition prepared in the Examples and Comparative Examples was continuously extruded for 30 minutes through a FUJIFILM-Dimatix Cartridge Head with 16 nozzles, and then the extrusion stability was evaluated according to the following evaluation criteria. The results are shown in Table 9 below.

[0548] <Evaluation Criteria for Discharge Stability>

[0549] ○: No more than one nozzle will not eject ink.

[0550] △: 2 to 5 nozzles are not ejecting ink

[0551] X: No ink output from more than 5 nozzles.

[0552] [Table 9]

[0553]

[0554] Based on the above experimental results, the light conversion ink composition prepared using an additive containing at least one compound represented by Chemical Formula 4 exhibits a light conversion efficiency of 33% to 34% and a lightfastness of 80% to 82%, which is significantly superior to the comparative examples without the additive. Conversely, in Comparative Examples III-1 and III-2, which do not contain an additive containing at least one compound represented by Chemical Formula 4, the light conversion efficiency is as low as 21% to 22% and the lightfastness is 55%, which is still not excellent.

[0555] Furthermore, the light-converting ink composition prepared with the above-mentioned luminescent particles and the above-mentioned additives can be judged to have excellent ejection stability, because in the ejection stability evaluation, one or fewer nozzles failed to eject ink, but in the cases of Comparative Examples III-1 and III-2, which do not contain additives containing at least one compound represented by Chemical Formula 4, five or more nozzles failed to eject ink.

[0556] In Reference Example III-1, where the content of an additive containing at least one compound represented by Chemical Formula 4 is less than 1% by weight based on the total weight of the solid components in the light conversion ink composition, the light conversion efficiency and lightfastness are low, and 2 to 5 nozzles fail to eject ink during the ejection stability evaluation, thus the ejection stability is generally low. In Reference Example III-2, where the content of an additive containing at least one compound represented by Chemical Formula 4 is 15% by weight or more based on the total weight of the solid components in the light conversion ink composition, the ejection stability is also generally low.

[0557] Therefore, it can be seen that the coating film formed by a light conversion ink composition containing 1 to 15% by weight of an additive comprising at least one compound represented by chemical formula 4, based on the total weight of the solid components in the light conversion ink composition, has improved light conversion efficiency, lightfastness and extrusion stability.

Claims

1. A light-converting ink composition comprising luminescent particles, polymerizable monomers, and additives. The additive contains at least one compound selected from the following chemical formulas 2 to 4, and Based on the total weight of the light-conversion ink composition, the content of at least one compound selected from the following chemical formulas 2 to 4 is greater than 0.1% by weight and less than 20% by weight: [Chemical Formula 2] In the chemical formula 2, R 21 and R 22 Each is independently a divalent to tetravalent hydrocarbon group having 1 to 10 carbon atoms; R 23 To R 26 Each is independently hydrogen, substituted or unsubstituted alkyl, thiol group, or [other compounds] having 1 to 5 carbon atoms. R 27 A substituted or unsubstituted alkylene group having 1 to 5 carbon atoms; n2 is an integer from 1 to 5, and when n2 is greater than 2, multiple R 22 R 25 and R 26 They can each be independent and different from each other. [Chemical Formula 3] In the chemical formula 3, R 28 and R 29 Each can be either hydrogen or methyl; m2 is an integer from 1 to 3, and when m2 is greater than 2, multiple R 29 But they are different. [Chemical Formula 4] In the chemical formula 4, R 41 It can be hydrogen or methyl; X4 is either O or -NH-; R 43 It is a straight bond or an alkylene group having 1 to 10 carbon atoms; R 44 and R 45 Each is independently hydrogen, an alkyl group having 1 to 20 carbon atoms, an allyl group, or a cycloalkyl group; R 42 For substituted or unsubstituted alkylene, arylene, alkylarylene, or alkylene groups having 1 to 20 carbon atoms , ,or , where R 46 R 48 R 49 R 410 R 411 R 413 R 414 Each is independently a substituted or unsubstituted alkylene group having 1 to 10 carbon atoms; R 47 and R 412 Each is independently hydrogen, or a substituted or unsubstituted alkyl group having 1 to 10 carbon atoms; l4, m4, and n4 are each an independent integer from 1 to 3.

2. The light conversion ink composition of claim 1 further comprises a silane coupling agent.

3. The light conversion ink composition of claim 2, wherein the silane coupling agent has at least one organic functional group selected from the group consisting of epoxy, (meth)acryloyloxy, mercapto, and amino.

4. The light conversion ink composition of claim 1, wherein the polymerizable monomer comprises a compound represented by the following chemical formula 5: [Chemical Formula 5] In the chemical formula 5, R 51 The substituted or unsubstituted alkylene group having 1 to 20 carbon atoms, the substituted or unsubstituted cycloalkylene group having 3 to 10 carbon atoms, the substituted or unsubstituted arylene group having 5 to 20 carbon atoms, the substituted or unsubstituted heteroarylene group having 2 to 15 carbon atoms, the substituted or unsubstituted arylalkylene group having 6 to 30 carbon atoms, the substituted or unsubstituted heteroarylalkylene group having 3 to 30 carbon atoms, the substituted or unsubstituted alkenylene group having 2 to 10 carbon atoms, or the substituted or unsubstituted ynylene group having 2 to 10 carbon atoms; R 52 and R 53 Each can be independently a hydrogen atom or a methyl group; m5 is an integer from 1 to 15.

5. The light conversion ink composition of claim 4, wherein the polymerizable monomer further comprises at least one of a monofunctional monomer, a difunctional monomer, and a polyfunctional monomer.

6. The photoconversion ink composition of claim 4, wherein the compound represented by the chemical formula 5 is 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.

7. The light-conversion ink composition of claim 1, further comprising a compound represented by the following chemical formula 6: [Chemical Formula 6] In the chemical formula 6, Z represents 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. R 67 and R 68 Each is independently a straight-bonded, substituted or unsubstituted alkylene group having 1 to 30 carbon atoms, -OR 69 -、-OC(=O)R 610 -、-(OCH2CH2) p - or -(OCH2CH2CH2) q -; Q1 and Q2 can each be a straight bond, an oxygen atom, a sulfur atom, or -NH-; D represents an oxygen atom, a sulfur atom, or is equal to NH; R 69 A substituted or unsubstituted alkylene group having 1 to 30 carbon atoms; R 610 A substituted or unsubstituted alkylene group having 4 to 30 carbon atoms; p and q are each independent integers from 1 to 150.

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

9. The photoconversion ink composition of claim 8, wherein the antioxidant comprises at least one of an antioxidant containing phenolic compounds and phosphorus compounds, and an antioxidant containing phenolic compounds and sulfur compounds.

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

11. The light-converting ink composition of claim 10, 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.

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

13. A light-conversion laminate substrate manufactured using the light-conversion ink composition as described in any one of claims 1 to 12.

14. A backlight unit comprising the light conversion laminate substrate as described in claim 13.

15. A light-converting pixel substrate manufactured using the light-converting ink composition as described in any one of claims 1 to 12.

16. An image display device, comprising the backlight unit as claimed in claim 14.

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

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