KR102458255B1 - Method for manufacturing quantumdot-polymer complex and quantumdot optical film manufactured therefrom - Google Patents

Abstract

The present invention relates to a method for producing a quantum dot-polymer complex and a quantum dot optical film comprising a quantum dot-polymer complex prepared therefrom, and more particularly, to a thiol between the thiol group and the reactive monomer after replacing a ligand on the surface of the quantum dot with a thiol group A quantum dot-polymer complex is prepared through the ene reaction. A quantum dot optical film including the same may exhibit improved barrier properties.

Description

Quantum dot-quantum dot optical film comprising a quantum dot-polymer composite manufacturing method and a quantum dot-polymer composite prepared therefrom

The present invention relates to a method for producing a quantum dot-polymer complex and a quantum dot optical film comprising a quantum dot-polymer complex prepared therefrom, and more particularly, to a quantum dot-polymer complex through a thiolene reaction after exchanging the ligand of the quantum dot It relates to a quantum dot optical film comprising a manufacturing method and a quantum dot-polymer composite prepared from the manufacturing method and having improved barrier properties.

Quantum dots (QDs) are so-called semiconductor nanocrystals, which can emit light of different wavelengths for each particle size without changing the material type and can produce various colors, and have higher color purity and light stability than conventional light emitting materials. Because of its advantages, it is attracting attention as a next-generation light emitting device.

These quantum dots are dispersed in a polymer matrix and applied to a display in the form of a complex, playing a major role in realizing high brightness and high color reproduction of the display. However, unlike inorganic phosphors, since quantum dots are vulnerable to external factors such as moisture or oxygen, there is a problem in that luminance decreases when exposed for a long time.

In order to solve this problem, the surface of the quantum dots can be coated with a polymer material. Conventionally, because the quantum dots and the reactive monomers were mixed at once and then polymerized to prepare them, the quantum dots cannot be uniformly dispersed in the solvent due to the difference in polarity between the materials and are not uniformly dispersed in the solvent. , or there was a problem that the polymerized polymer was not evenly formed on the surface of the quantum dot.

In addition, in the case of applying quantum dots to a display, conventionally, a barrier film including a barrier layer for preventing or removing moisture or oxygen, etc. is disposed on both sides of a polymer layer containing quantum dots to prepare a quantum dot optical film. However, in the conventional quantum dot optical film, deterioration of the edge portion occurred, and the manufacturing cost increased due to the high price of the barrier film, so both technical and economical aspects did not produce satisfactory results.

The problem to be solved by the present invention is to provide a method for producing a quantum dot-polymer composite that has excellent compatibility and miscibility between quantum dots and reactive monomers, and can increase the stability of quantum dots by forming a uniform polymer film on the surface of quantum dots .

Another problem to be solved in the present invention is to provide a quantum dot optical film having excellent barrier properties even when a general optical film is used instead of a barrier film.

In order to achieve the above technical problem, the present invention comprises the steps of (i) mixing a quantum dot, a dispersing agent, and a thiol compound having at least one thiol group (-SH) at the terminal to prepare a first solution; (ii) preparing a second solution comprising a reactive monomer and a polymerization initiator; and (iii) mixing and polymerizing the first solution and the second solution.

In addition, the present invention provides a quantum dot composition comprising a quantum dot-polymer composite prepared by the above manufacturing method and a quantum dot optical film comprising the same.

According to the quantum dot-polymer composite manufacturing method of the present invention, compatibility and miscibility between the quantum dot and the reactive monomer is increased, and the reactive monomer is polymerized on the surface of the quantum dot to minimize the vulnerability of the quantum dot itself to external factors, decrease in brightness, and the like.

The quantum dot optical film including the quantum dot-polymer composite according to the manufacturing method has excellent barrier properties even when a general optical film is used instead of the barrier film, and can prevent or delay deterioration of luminance and color coordinates.

1 is a cross-sectional view schematically showing a quantum dot optical film according to the present invention.
2 is a photograph showing dispersibility in the case of dispersing in the reactive monomer after exchanging the ligand of the quantum dot with a thiol group and in the case of dispersing in the reactive monomer without exchanging the ligand.

EMBODIMENT OF THE INVENTION Hereinafter, this invention is demonstrated.

All terms (including technical and scientific terms) used in this specification may be used in the meaning commonly understood by those of ordinary skill in the art to which the present invention pertains, unless otherwise defined. In addition, terms defined in a commonly used dictionary are not to be interpreted ideally or excessively unless clearly defined in particular.

In addition, throughout this specification, when a part "includes" a certain component, it means that other components may be further included, rather than excluding other components, unless specifically stated to the contrary. In addition, throughout the specification, "on" or "on" means that it includes not only the case where it is located above or below the target part, but also the case where there is another part in the middle, and the direction of gravity must be It does not mean that it is positioned above the reference.

In addition, in this specification, "(meth)acrylate" represents acrylate and methacrylate, "(meth)acryl" represents acryl and methacryl, and "(meth)acryloyl" represents acryloyl and methacryloyl.

In addition, in this specification, "monomer" and "monomer" have the same meaning. The monomer in this invention is distinguished from an oligomer and a polymer, and a weight average molecular weight says the compound whose weight average molecular weight is 1,000 or less. In this specification, "photopolymerizable monomer" refers to a group involved in a polymerization reaction, such as a (meth)acrylate group.

<Quantum dot-polymer composite manufacturing method>

Hereinafter, a method for producing a quantum dot-polymer composite according to an embodiment of the present invention will be described. However, it is not limited only by the following manufacturing method, and the steps of each process may be modified or selectively mixed as needed.

In the present invention, after replacing the ligand of the quantum dot with a thiol group, the quantum dot-polymer complex is prepared through a polymerization reaction between the thiol group and the reactive monomer. For a preferred embodiment of the preparation method, (i) preparing a first solution by mixing quantum dots, a dispersing agent, and a thiol compound having at least one thiol group (-SH) at the terminal; (ii) preparing a second solution comprising a reactive monomer and a polymerization initiator; and (iii) mixing and polymerizing the first solution and the second solution.

Hereinafter, the manufacturing method is divided into each process step and described as follows.

(i) replacing the ligand of the quantum dot with a thiol group

In step (i), a first solution is prepared by mixing quantum dots, a dispersing agent, and a thiol compound having at least one thiol group (-SH) at the terminal. For a preferred embodiment, after dispersing the quantum dots in a dispersing agent, a thiol compound is added to the solution in which the quantum dots are dispersed, and stirring may be performed at room temperature. A first solution containing quantum dots whose surface is substituted with a thiol group is prepared through a ligand exchange reaction while stirring.

Quantum dots (QDs) are nano-sized semiconductor materials, and may have different energy band gaps depending on their size and composition, and thus may emit light of various emission wavelengths.

These quantum dots have a homogeneous single-layer structure; multi-layer structures such as core-shell shapes, gradient structures, and the like; Or it may be a mixed structure thereof. When the shell is multi-layered, each layer may contain different components from each other, such as (semi)metal oxides.

The quantum dot (QD) may be freely selected from a group II-VI compound, a group III-V compound, a group IV-VI compound, a group IV element, a group IV compound, and combinations thereof. When the quantum dot is in a core-shell form, the core and the shell may be freely configured from the components exemplified below, respectively.

For example, the group II-VI compound may include a diatomic compound selected from the group consisting of CdO, CdS, CdSe, CdTe, ZnO, ZnS, ZnSe, ZnTe, HgS, HgSe, HgTe, MgSe, MgS, and mixtures thereof; CdSeS, CdSeTe, CdSTe, ZnSeS, ZnSeTe, ZnSTe, HgSeS, HgSeTe, HgSTe, CdZnS, CdZnSe, CdZnTe, CdHgS, CdHgSe, CdHgZnTe, HgZnS, HgZnSe, HgZnTe, MgZnS, MgZnS and mixtures of three members selected from the group consisting of: bovine compounds; and CdZnSeS, CdZnSeTe, CdZnSTe, CdHgSeS, CdHgSeTe, CdHgSTe, HgZnSeS, HgZnSeTe, HgZnSTe, and mixtures thereof.

In another example, the group III-V compound is a binary compound selected from the group consisting of GaN, GaP, GaAs, GaSb, AlN, AlP, AlAs, AlSb, InN, InP, InAs, InSb, and mixtures thereof; a ternary compound selected from the group consisting of GaNP, GaNAs, GaNSb, GaPAs, GaPSb, AlNP, AlNAs, AlNSb, AlPAs, AlPSb, InNP, InNAs, InNSb, InPAs, InPSb, and mixtures thereof; and GaAlNPs, GaAlNAs, GaAlNSb, GaAlPAs, GaAlPSb, GaInNP, GaInNAs, GaInNSb, GaInPAs, GaInPSb, InAlNP, InAlNAs, InAlNSb, InAlPAs, InAlPSb, and mixtures thereof. have.

In another example, the group IV-VI compound is a binary compound selected from the group consisting of SnS, SnSe, SnTe, PbS, PbSe, PbTe, and mixtures thereof; a ternary compound selected from the group consisting of SnSeS, SnSeTe, SnSTe, PbSeS, PbSeTe, PbSTe, SnPbS, SnPbSe, SnPbTe, and mixtures thereof; and a quaternary compound selected from the group consisting of SnPbSSe, SnPbSeTe, SnPbSTe, and mixtures thereof.

In another example, the group IV element may be selected from the group consisting of Si, Ge, and mixtures thereof. The group IV compound may be a di-element compound selected from the group consisting of SiC, SiGe, and mixtures thereof.

The above-described binary, ternary, or quaternary compound may be present in the particle at a uniform concentration, or may be present in the same particle as the concentration distribution is partially divided into different states. Also, one quantum dot may have a core/shell structure surrounding another quantum dot. The interface between the core and the shell may have a concentration gradient in which the concentration of elements present in the shell decreases toward the center.

The form of the quantum dot is not particularly limited as long as it is a form generally used in the art. For example, spherical, rod-shaped, pyramidal, disk-shaped, multi-arm, or cubic nanoparticles, nanotubes, nanowires, nanofibers, and nanoplatelet particles and the like can be used.

In addition, the size of the quantum dot is not particularly limited, and may be appropriately adjusted within a conventional range known in the art. For example, the average particle diameter (D ₅₀ ) of the quantum dots may be about 2 to 10 nm. In this way, when the particle size of the quantum dots is controlled to be approximately in the range of about 2 to 10 nm, light of a desired color may be emitted. For example, when the particle size of the quantum dot core/shell containing InP is about 5 to 6 nm, light having a wavelength of about 520 to 550 nm may be emitted, while the particle size of the quantum dot core/shell containing InP is about In the case of 7 to 8 nm, light having a wavelength of about 620 to 640 may be emitted. For example, non-cadmium (Cd)-based group III-V QDs (eg, InP, InGaP, InZnP, GaN, GaAs, GaP) can be used as the blue-emitting quantum dots (QDs).

In addition, the quantum dots may have a full width of half maximum (FWHM) of an emission wavelength spectrum of about 40 nm or less, and color purity or color reproducibility may be improved in this range. In addition, since the light emitted through the quantum dots is emitted in all directions, a wide viewing angle may be improved.

A part or all of the surface of the quantum dots (QD) may be substituted with an organic ligand. Such an organic ligand may be bound to the surface of the quantum dot to serve to stabilize the quantum dot. Non-limiting examples of such organic ligands include C5 to C20 alkyl carboxylic acids, alkenyl carboxylic acids or alkynyl carboxylic acids; pyridine; mercapto alcohol; thiol; phosphine; phosphine oxide; primary amines; secondary amines; or a combination thereof.

In step (i), the dispersant serves to disperse the quantum dots before substituting the ligands of the quantum dots. The dispersing agent according to the present invention may be used without particular limitation as long as it is used to disperse quantum dots in the art. Specifically, it may be a material containing a conventional carbon double bond known in the art, and more specifically, may be a monomer containing at least one of a (meth)acrylic group, a vinyl group, and an allyl group, but is not limited thereto.

After dispersing the quantum dots in the dispersant, a thiol compound is added to the dispersion solution.

The thiol compound may be substituted on the surface of the quantum dot to improve the dispersion stability of the quantum dot to a solvent to stabilize the quantum dot. In addition, the thiol group substituted on the surface of the quantum dot may be reacted with a reactive monomer to be described later with thiolene to form a uniform polymer film.

The thiol compound may be a compound containing a thiol group (-SH), specifically, a compound containing one or more, more specifically, two or more (eg, 2 to 4) thiol groups at the terminal.

As the thiol compound usable in the present invention, any thiol-terminated compound in the art can be used without particular limitation, for example, a thiol-terminated polyester monomer, a thiol-terminated poly(meth)acrylate monomer, etc. but is not limited thereto. Here, the polyester is a compound including a plurality of ester groups in the molecular skeleton, and may include, for example, 2 to 4 ester groups. In addition, the polyacrylate monomer is a compound including a plurality of (meth)acrylate groups in the molecular skeleton, and may include, for example, 2 to 4 (meth)acrylate groups.

Specifically, non-limiting examples of the thiol compound include pentaerythritol tetrakis (3-mercaptopropionate), trimethylolpropane tris (3-mercaptopropionate) [trimethylopropane tris (3-mercaptopropionate)], penta Erythritol tetrakis(3-mercaptopropionate) [pentaerythritol tetrakis(3-mercaptopropionate)], pentaerythritol tetrakis(2-mercaptoacetate) [pentaerythritol tetrakis(2-mercaptoacetate)], dipentaerythritol hexa kiss(3-mercaptopropionate), tris[2-(3-mercaptopropionyloxy)alkyl]isocyanurate (tris[2-(3-mercaptopropionyl oxy)alkyl]isocyanurate), tris-[2 -(3-mercaptopropionyloxy)-ethyl]isocyanurate (tris[2-(3-mercaptopropionyloxy)ethyl] isocyanutte), pentaerythritol tetrakis(3-mercaptobutylate) (pentaerythritol tetrakis(3 -mercaptobutylate), ethylene glycol bis(3-mercaptopropionate) (ethylene glycol bis(3-mercapto propionate)), tetraethylene glycol bis(3-mercaptopropionate) (tetraethylene glycol bis(3-mercaptopropionate) ) and the like, and these may be used alone or in combination of two or more.

The content of the thiol compound may be appropriately adjusted within a range known in the art. For example, in the first solution, the mixing ratio of the dispersant and the thiol compound may be 1:0.1-5 volume ratio, more preferably 1:0.5-5 volume ratio.

(ii) second solution preparation step

In step (ii), a second solution including a reactive monomer and a polymerization initiator is prepared.

The reactive monomer serves to form a quantum dot-polymer complex by reacting with a thiol group uniformly substituted on the surface of the quantum dot with thiolene. As the reactive monomer according to the present invention, a conventional monomer capable of radical polymerization in the art may be used without limitation.

For example, the reactive monomer may include at least one of a (meth)acrylic group, a vinyl group, and an allyl group.

Specifically, 1,6-hexanediol diacrylate (1,6-hexanedioldiacrylate), 1,6-cyclohexanediol diacrylate (1,6-cyclohexanediol diacrylate), 2,2-dimethyl-1, 3-propanediol diacrylate (2,2-dimethyl-1,3-propanediol diacylate), diethylene glycol diacrylate, 1,3-butylene glycol dimethacrylate (1,3) -butylene glycol imethacrylate), trimethylolpropane trimethacrylate, isobonyl acrylate, isobonyl methacrylate, tetrahydrofuryl acrylate, acrylo Acryloyl morpholine, 2-phenoxyethyl acrylate, tripropylene-glycol diacrylate, trimethylolpropane triacrylate, pentaerythritol Mono (meth) acrylate, pentaerythritol di (meth) acrylate, pentaerythritol triacrylate, pentaerythritol trimethacrylate, dipentaerythritol hexaacrylate ) and dipentaerythritol hexamethacrylate. These may be used alone or two or more may be used in combination.

On the other hand, in order to form a uniform polymer film on the surface of the quantum dot, it is preferable to appropriately control the ratio of use between the thiol group located on the surface of the quantum dot and the polymerizable functional group of the reactive monomer.

Accordingly, the ratio of the polymerizable functional group included in the reactive monomer to the thiol group of the thiol compound may be 1:0.25-2.

In the second solution, the polymerization initiator generates radicals to promote the thiolene reaction. The material used as the polymerization initiator is not particularly limited as long as it can generate radicals in the art, and for example, a photoinitiator or a thermal initiator.

The photoinitiator is a component that is excited by a light source such as ultraviolet (UV) light to initiate photopolymerization, and a conventional photopolymerization photoinitiator in the art may be used without limitation. For example, an acetophenone-based compound, a benzophenone-based compound, a thioxanthone-based compound, a benzoin-based compound, a triazine-based compound, an oxime-based compound, and the like may be used.

Non-limiting examples of usable photoinitiators, Irgacure 184, Irgacure 369, Irgacure 651, Irgacure 819, Irgacure 90, benzionalkyl ether (Benzionalkyl ether), benzophenone (Benzophenone), benzyl dimethyl catal (Benzyl dimethyl kata), Hydroxycyclohexyl phenylacetone, Chloroacetophenone, 1,1-Dichloro acetophenone, Diethoxy acetophenone, Hydroxyacetophenone (diethoxy) Acetophenone, 2-chlorothioxanthone, 2-ETAQ (2-EthylAnthraquinone), 1-hydroxy-cyclohexyl-phenyl-ketone (1-Hydroxy-cyclohexyl-phenyl-ketone) ), 2-hydroxy-2-methyl-1-phenyl-1-propanone (2-Hydroxy-2-methyl-1-phenyl-1-propanone), 2-hydroxy-1-[4- (2- Hydroxyethoxy)phenyl]-2-methyl-1-propanone (2-Hydroxy-1-[4-(2-hydroxyethoxy)phenyl]-2-methyl-1-propanone), methylbenzoylformate etc. These may be used alone or two or more of them may be used in combination.

The thermal initiator generates radicals by a predetermined heat to initiate polymerization, and any conventional thermal polymerization initiator known in the art may be used without limitation. The thermal initiator may have a use temperature of about 35 °C or higher, specifically about 35-100 °C.

Possible thermal initiators in the present invention include azo-based compounds, peroxide-based compounds, hydroperoxide-based compounds, hydrazide-based compounds, imidazole-based compounds, and/or radicals under heating conditions. Other thermal initiator(s) capable of releasing Specifically, there are azonitrile, azo ester, azo amide, organic peroxide, inorganic peroxide, organic hydroperoxide, inorganic hydroperoxide, or mixtures thereof.

More specific examples include benzoyl peroxide, di-t-amyl peroxide, t-butyl peroxy benzoate, di-cumyl peroxide, t-amyl hydroperoxide and t-butyl hydroperoxide, 2,5-dimethyl -2,5-di-(t-butylperoxy)hexyne-3) [2,5-Di (tert-butylperoxy)-2,5-dimethyl-3-hexyne], 2,5-dimethyl-2, 5-di-(tert-butylperoxy)hexane [2,5-Bis(tert-butylperoxy)-2,5-dimethylhexane], DuPont's VAZO compound [eg, VAZO 52 (2,2) '-Azobis (2,4-dimethylpentanenitrile)), Bazo 64 (2,2'-Azobis (2-methylpropanenitrile)), Bazo 67 (2,2'-Azobis (2-methylbutane) nitrile)), Vazo 88 (2,2'-azobis(cyclohexanecarbonitrile)), etc.], but is not limited thereto.

The content of the polymerization initiator may be appropriately adjusted within a range known in the art. For example, it may be 0.1 to 5 parts by weight, more specifically 0.1 to 3 parts by weight, based on 100 parts by weight of the reactive monomer.

According to one example, the second solution may further include a polymerization inhibitor.

The polymerization inhibitor serves to inhibit the polymerization reaction by trapping radicals during polymerization through a thiolene reaction between the thiol group of the quantum dot substituted with the thiol group and the reactive monomer.

Specific examples of the polymerization inhibitor usable in the present invention include hydroquinone, methylhydroquinone, 2,5-di-t-butyl hydroquinone, 4-methoxyphenol, pyrogallol, techol, 2,6-di-t -Butyl-4-methylphenol, 2-naphthol, tris(N-hydroxy-N-nitrosophenylaminato-O,O')aluminium (Tris(N-hydroxy-N-nitrosophenylaminato-O,O')aluminium ) or a combination thereof, but is not limited thereto.

The content of the polymerization inhibitor is not particularly limited, and may be, for example, 0.01 to 2 parts by weight, more specifically 0.01 to 1 parts by weight, based on the reactive monomer.

Optionally, in the quantum dot-polymer composite manufacturing method according to the present invention, in addition to the above-described components, quantum dots-at least one additive known in the art within the range that does not affect the physical properties of the polymer composite (eg, light scattering agent, solvents, dispersants, etc.) may be further included without limitation. In this case, the content of the additive may be appropriately adjusted within a range known in the art.

(iii) mixing and polymerizing the first solution and the second solution;

In step (iii), the quantum dot-polymer composite is prepared by mixing and stirring the first solution and the second solution prepared in the previous step in a predetermined ratio and polymerization.

According to an example, when mixing the first solution and the second solution, the mixing ratio of the first solution and the second solution may be 1: 0.5 to 5 by weight.

The polymerization conditions in step (iii) are not particularly limited and may be appropriately adjusted within a range known in the art. For example, when a thermal initiator is used, heat above the temperature at which the polymerization reaction starts may be applied.

For a specific example of step (iii), the first solution and the second solution are stirred at room temperature for 0.5 to 2 hours to prepare a mixed solution, and then the temperature of the mixed solution is raised to 50 to 100° C., followed by polymerization. may include.

As another specific example of this step (iii), in step (iii), the first solution and the second solution may be mixed at once, or the first solution and a part of the second solution are stirred at room temperature for 0.5 to 2 hours. to prepare a mixed solution; and heating the mixed solution to 50 to 100° C. and then supplying the remainder of the second solution at a flow rate of 0.01 to 1 ml/min for polymerization. For example, based on 100 parts by weight of the second solution, 30 to 80 parts by weight of the second solution may be mixed with the first solution, and the temperature of the mixed solution may be raised, and then 70 to 20 parts by weight of the remainder of the second solution may be supplied.

Conventionally, when a polymerization reaction is performed by mixing the quantum dots and the reactive monomer at once without exchanging the ligands of the quantum dots, the quantum dots may not be evenly dispersed in the solvent due to the difference in polarity between the quantum dots and the reactive monomer and may be precipitated. Therefore, the types of reactive monomers that can be used for the reaction are limited, and there is a problem of poor compatibility with quantum dots.

In the present invention, by exchanging the ligand of the quantum dot with a thiol group and then mixing and polymerization with the reactive monomer, miscibility between the quantum dot and the reactive monomer can be improved, so that the polymerization reaction can occur without precipitation of the quantum dot.

The quantum dot-polymer composite prepared by the above method may have a viscosity at 55° C. of 1000 to 4000 cps, specifically 1800 to 3000 cps. In addition, the quantum dot-polymer composite may have a weight average molecular weight (Mw) of 1000 to 10000 g/mol, specifically, 1000 to 7000 g/mol.

When the viscosity of the quantum dot-polymer composite becomes higher than the above-mentioned range, the viscosity of the quantum dot composition increases, thereby causing a problem of poor processability when manufacturing an optical film. In addition, in order to lower the viscosity of the quantum dot composition, it is necessary to use a large amount of a monofunctional photoreactive monomer having a low viscosity, thereby reducing the range of usable raw materials. In addition, when the content of the monofunctional photoreactive monomer included in the quantum dot composition is increased, the thermal stability of the optical film when manufactured as an optical film is deteriorated, which may cause a problem in terms of reliability.

<Quantum dot composition>

In the present invention, the quantum dot composition includes a quantum dot-polymer complex and a photopolymerizable monomer, and may further include a diffusion agent and/or other additives known in the art, if necessary.

Hereinafter, the composition of the quantum dot composition according to the present invention will be described.

(1) Quantum dot-polymer complex

The quantum dot composition according to the present invention includes the quantum dot-polymer composite prepared by the above-described quantum dot-polymer composite manufacturing method.

(2) photopolymerizable monomer

In the quantum dot composition in the present invention, the photopolymerizable monomer is a formulation in which the quantum dot-polymer complex is dispersed, that is, a component that forms a polymer matrix, and controls the overall crosslinking density of the polymer matrix to express the structure and general properties of the matrix. , flexibility, and adhesion and adhesion to other materials can be improved.

These photopolymerizable monomers are monomers having a carbon-carbon unsaturated bond at the terminal, specifically, having a carbon-carbon double bond or carbon-carbon triple bond at the terminal, and more specifically a (meth)acrylate group, acryloyl group at the terminal , may have at least one of a methacryloyl group, an aryl group, and a vinyl group.

According to one example, the photopolymerizable monomer may be a (meth)acrylate monomer.

The (meth) acrylate monomer includes a monofunctional acrylic monomer (f = 1), a bifunctional acrylic monomer (f = 2), depending on the number of polymerizable functional groups, such as (meth) acrylate groups, included in one molecule; It may be classified into a trifunctional acrylate monomer (f = 3) and a polyfunctional acrylate monomer having a tetrafunctional or higher function (f ≥ 4).

In the present invention, at least one (meth)acrylate monomer is used as the photopolymerizable monomer, and specifically, a trifunctional or less functional (meth)acrylate monomer; and a polyfunctional (meth)acrylate monomer having a tetrafunctional or higher function may be mixed.

Here, the low-functionality (meth)acrylate monomer and the polyfunctionality (meth)acrylate monomer both contribute to forming a crosslinked structure through photocuring. In particular, the polyfunctional (meth)acrylate monomer containing at least four polymerizable functional groups forms a more dense and dense three-dimensional network crosslinking structure due to the number of functional groups included in the molecule, thereby forming a crosslink density and glass transition of the matrix. A temperature (Tg) improvement effect can be realized. In consideration of these physical properties, the mixing ratio of the low-functionality (meth)acrylate monomer and the polyfunctionality (meth)acrylate monomer may be 90:10 to 10:90 by weight.

The low-functionality (meth)acrylate monomer may be used without limitation as long as it is a (meth)acrylate monomer containing 3 or less, specifically 2 to 3, photopolymerizable unsaturated groups in the molecule. According to an example, the low-functionality (meth)acrylate may include at least one of a bifunctional (meth)acrylate monomer and a trifunctional (meth)acrylate monomer, and specifically, a bifunctional (meth)acrylate monomer may include.

Examples of the bifunctional (meth)acrylate monomer usable in the present invention include ethylene glycol di(meth)acrylate, propylene glycol di(meth)acrylate, polyolefin glycol di(meth)acrylate, ethoxylated polypropylene glycol di( Meth)acrylate, 2-hydroxy-3-acryloyloxypropyl methacrylate, 2-hydroxy-1,3-dimethacryloxypropane, dioxane glycol di(meth)acrylate, tricyclodecanedi Methanol di(meth)acrylate, 1,4-butanediol di(meth)acrylate, glycerin di(meth)acrylate, 1,6-hexanediol di(meth)acrylate, 1,9-nonanediol di(meth) ) acrylate, 1,10-decanediol di(meth)acrylate, neopentylglycol di(meth)acrylate, 2-methyl-1,8-octanediol di(meth)acrylate, 1,9-nonanediol Di(meth)acrylate, butylethylpropanediol di(meth)acrylate, 3-methyl-1,5-pentanediol di(meth)acrylate, and di(meth)acrylate having an aromatic ring, for example Examples thereof include, but are not limited to, ethoxylated bisphenol A di(meth)acrylate, propoxylated ethoxylated bisphenol A di(meth)acrylate, and ethoxylated bisphenol F di(meth)acrylate. These may be used alone or two or more may be used in combination.

Examples of the trifunctional (meth)acrylate monomer usable in the present invention include ethoxylated glycerin tri(meth)acrylate, trimethylolpropane tri(meth)acrylate, ethoxylated trimethylolpropane tri(meth)acrylate, propoxy and trimethylolpropane tri(meth)acrylate and pentaerythritol tri(meth)acrylate.

The weight average molecular weight (Mw) of the low-functionality (meth)acrylate monomer is about 100 g/mol or more, and specifically, may be about 100 to 600 g/mol.

As the polyfunctional (meth)acrylate monomer, a known (meth)acrylate monomer containing 4 or more, specifically 4 to 6, photopolymerizable unsaturated groups in a molecule may be used without limitation. According to an example, the polyfunctional (meth) acrylate monomer may include at least one of a tetrafunctional (meth) acrylate monomer and a pentafunctional (meth) acrylate monomer, and specifically, a tetrafunctional (meth) acrylate monomer can be

Non-limiting examples of polyfunctional (meth)acrylate monomers usable in the present invention include pentaerythritol tetra(meth)acrylate, ditrimethylolpropane tetra(meth)acrylate, ethoxylated pentaerythritol tetra(meth)acryl tetrafunctional (meth)acrylate monomers such as rate and the like; 5-functional (meth)acrylate monomers such as dipentaerythritol pentaacrylate, propionic acid-modified dipentaerythritol pentaacrylate, dipentaerythritol pentamethacrylate, propionic acid-modified dipentaerythritol pentamethacrylate; 6-functional (meth)acrylate monomers such as dipentaerythritol hexaacrylate, caprolactone-modified dipentaerythritol hexaacrylate, dipentaerythritol hexamethacrylate, caprolactone-modified dipentaerythritol hexamethacrylate, etc. These may be used alone, or two or more of them may be used in combination. According to an example, the polyfunctional (meth)acrylate monomer may be the same tetrafunctional (meth)acrylate monomer, specifically, ditrimethylolpropane tetra(meth)acrylate.

The weight average molecular weight (Mw) of the polyfunctional (meth)acrylate monomer may be about 300 g/mol or more, specifically, about 300 to 1,000 g/mol.

In addition, the photopolymerizable monomer of the present invention may include carboxylate vinyl ester compounds such as acrylic acid, methacrylic acid, maleic acid, itaconic acid, fumaric acid, 3-butenoic acid, vinyl acetate, and vinyl benzoate; alkenyl aromatic compounds such as styrene, alpha-methyl styrene, vinyl toluene, and vinyl benzyl methyl ether; vinyl cyanide compounds such as acrylonitrile and methacrylonitrile; One or more types of unsaturated amide compounds such as acrylamide and methacrylamide may be included. These monomers may be used alone or in combination with the above-mentioned (meth)acrylate monomers.

In the quantum dot composition of the present invention, the content of the photopolymerizable monomer may be appropriately adjusted within a range known in the art in consideration of the structure and physical properties of the polymer matrix. For example, the mixing ratio of the quantum dot-polymer complex dispersed solution and the photopolymerizable monomer may be 1: 3 to 5 weight ratio.

At this time, when the photopolymerizable monomer contains a low-functionality (meth)acrylate and a polyfunctionality (meth)acrylate monomer, the content of the low-functionality (meth)acrylate monomer is about 20 based on the total amount of the quantum dot composition to 60% by weight, and the content of the polyfunctional (meth)acrylate monomer may be about 10 to 50% by weight based on the total amount of the quantum dot composition (except for the barrier material). When the content of the polyfunctional (meth)acrylic monomer falls within the above range, the crosslinking structure and density of the matrix are improved by appropriately adjusting the viscosity and crosslinking density of the quantum dot composition, and the glass transition temperature (Tg) can be improved. .

(3) diffusion agent

In the quantum dot composition according to the present invention, the diffusing agent reflects light not absorbed by the light conversion material, and allows the light conversion material to absorb the reflected light again. That is, the diffusing agent may increase the amount of light absorbed by the light conversion material, thereby increasing light conversion efficiency.

The dispersing agent may be used without limitation, a dispersing agent component known in the art. Such a dispersing agent may be a dispersing agent solid or a dispersion in which the dispersing agent is dispersed. The dispersion in which the dispersing agent is dispersed may be an organic solvent such as PGMEA.

Non-limiting examples of dispersing agents that can be used include barium sulfate (BaSO 4 ), calcium carbonate (CaCO ₃ ), titanium dioxide (TiO ₂ ), zirconia (ZrO ₂ ), or combinations thereof. In addition, the average particle diameter or shape of the dispersing agent is not particularly limited, and may be appropriately selected within a configuration known in the art. For example, the average particle diameter (D ₅₀ ) may be 150 nm to 1500 nm, specifically, 180 nm to 1000 nm. When the average particle diameter of the diffusing agent is within the above-mentioned range, a more excellent light diffusion effect may be obtained, and light conversion efficiency may be increased.

The content of the dispersing agent may be appropriately adjusted within a range known in the art. As an example, it may be 0.1 to 10 parts by weight based on the total weight of the quantum dot composition. When the content of the diffusing agent falls within the above-mentioned range, it is possible to exhibit the effect of improving the light conversion efficiency without deteriorating the physical properties of the matrix.

<Quantum dot optical film>

(1) base film

In the quantum dot optical film 100 of the present invention, the first base film 20 and the second base film 30 are light-transmitting films, and it is possible to prevent the quantum dot-containing layer from being contaminated by foreign substances in the external environment.

The first base film 20 and the second base film 30 usable in the present invention may be used without limitation as long as it is a conventional light-transmitting film known in the art. According to one example, the light-transmitting film may have a light transmittance of about 70 to 100% at a wavelength of about 380 to 780 nm.

Examples of the material of the light-transmitting film include polyesters such as polyethylene naphthalate, polycarbonate, cycloolefine polymer, polyethylene terephthalate (PET), and the like; polyolefine, polysulfone, polyimide, silicone, polystyrene, polyacryl, polyvinylchloride, and the like, but is not limited thereto. These may be used alone or two or more may be used in combination.

The first base film 20 and the second base film 30 may have a single layer or a multi-layered form in which two or more resin films are laminated.

The thickness of the first base film 20 and the second base film 30 is not particularly limited, and may be appropriately adjusted within a typical thickness range used in the display field. For example, it may be about 10 to 200 μm.

On the other hand, the quantum dot optical film 100 of the present invention is a single or multi-layer inorganic coating layer that blocks moisture and/or oxygen between the first base film 20 and the second base film 30 and the quantum dot-containing layer. A separate barrier layer may not be included. For example, a separate barrier layer may not be coated on the surfaces of the first base film 20 and the second base film 30 of the present invention.

(2) Quantum dot-containing layer

In the quantum dot optical film 100 of the present invention, the quantum dot-containing layer 10 is a portion interposed between the first base film 20 and the second base film 30, and includes a photocured material of the quantum dot composition described above. .

Specifically, the quantum dot-containing layer 10 includes a polymer matrix 11 and a plurality of quantum dots dispersed in the polymer matrix 11 - a polymer composite 12 .

Here, the description of the quantum dot-polymer complex 12 is the same as that described for the above-described quantum dot-polymer complex 12, and thus will be omitted.

The polymer matrix 11 is impregnated with a plurality of quantum dots-polymer complexes. That is, a plurality of quantum dots-polymer complexes 12 may be interspersed within the polymer matrix 11 , or some quantum dots-polymer complexes 12 may be disposed on the surface of the matrix.

The polymer matrix 11 includes the remaining portion except for the quantum dot-polymer complex in the photocured material of the quantum dot composition. Specifically, a photopolymerizable monomer may be included, and for example, a diffusion agent may be further included. In this case, the diffusing agent may be included in an amount of 0.1 to 10 parts by weight based on the total weight of the quantum dot composition.

Specifically, the polymer matrix 11 may include a trifunctional or less functional (meth)acrylate monomer (eg, a bifunctional (meth)acrylate monomer); tetrafunctional or higher polyfunctional (meth)acrylate monomers (eg, tetrafunctional (meth)acrylate monomers); It may be a cured product of a composition comprising a. At this time, the low-functionality (meth) acrylate monomer is a trifunctional or less (meth) acrylate monomer having a weight average molecular weight (Mw) of about 100 to 600 g / mol (specifically, a bifunctional (meth) acrylate monomer), and the polyfunctional (meth) acrylate monomer is a tetrafunctional or more (meth) acrylate monomer having a weight average molecular weight (Mw) of about 300 to 1000 g/mol (specifically, tetrafunctional (meth)) acrylate monomer). The mixing ratio of the low-functionality (meth)acrylate monomer and the polyfunctionality (meth)acrylate monomer may be 90:10 to 10:90 by weight.

In the quantum dot-containing layer 10, the ratio of the polymer matrix 11 and the plurality of quantum dots-polymer composite 12 used may be appropriately adjusted within a conventional range known in the art. As an example, the mixing ratio of the plurality of quantum dots-polymer composite 12 and polymer matrix 11 may be 1: 3 to 5 by weight.

The thickness of the quantum dot-containing layer 10 is not particularly limited, but if the thickness of the quantum dot-containing layer is too thick, a problem may occur when applied (assembled) to a display, and when the thickness is too thin, quantum dots-polymer composites (12) Since there is no regular interval therebetween, entanglement may occur, or the surface of the quantum dot-polymer composite 12 may be exposed, thereby reducing the barrier properties of the film. Accordingly, the thickness of the quantum dot-containing layer 10 may be about 40 μm to 100 μm.
The quantum dot optical film of the present invention satisfies at least one of the following (i) to (iv) physical properties:
(i) The luminance value retention rate after 180 hours under blue light conditions is 80% or more,
(ii) the luminance value retention rate after 400 hours under blue light conditions is 60% or more,
(iii) Edge penetration by moisture and oxygen after 400 hours under blue light conditions is 250 um or less,
(iv) The luminance value retention rate after 14 days storage at -5 to 60°C is 95% or more.

Unlike the conventional quantum dot optical film, the quantum dot optical film 100 of the present invention has excellent barrier properties, even if it does not include a barrier layer between the general light-transmitting film and the quantum dot-containing layer. See Tables 2 and 3 below). In addition, the quantum dot-polymer composite was stored at -5 to 60 ° C. for 14 days, and then the quantum dot optical film prepared with the quantum dot-polymer composite was compared with the quantum dot optical film initially produced when compared to the brightness and There is almost no change in color coordinates, and through this, it can be confirmed that the quantum dot-polymer complex does not deteriorate even when the quantum dot-polymer complex is exposed to high temperatures for a long time. (See Table 3 below)

According to an example, after irradiating the quantum dot optical film of the present invention with light (about 450 nm) of blue wavelength under 25 ° C for about 400 hours, the amount of change in luminance compared to the initial luminance is about 50% or less, preferably about 40% or less. have.

According to another example, the quantum dot optical film produced after storing the quantum dot-polymer composite of the present invention for about 14 days by temperature (-5 ℃, 25 ℃, 40 ℃, 65 ℃), and the quantum dot-polymer composite is prepared and initially When the luminance of the produced quantum dot optical film is measured at 25° C., the change in luminance may be 5% or less, preferably 3% or less.

Meanwhile, in the present invention, the above-described embodiment of FIG. 1 is exemplarily described. However, it is also within the scope of the present invention to freely select and configure the number of each layer constituting the quantum dot optical film 100 and the order of their lamination according to the use. For example, the order of the respective layers 10 , 20 , 30 may be changed or other layers conventional in the art may be introduced to have a multi-layered structure rather than the exemplified structure.

The quantum dot optical film 100 of the present invention configured as described above may be mounted on various display devices requiring quantum dots (QD).

For one embodiment of such a display device, a quantum dot optical film; a light source unit including a light source for generating light; and a light guide plate for guiding the light. Here, the backlight unit may further include an optical member and a reflective sheet.

In another embodiment of the present invention, a display device including the above-described backlight unit is provided. The display may include a display panel and a backlight unit, and the display panel may be a liquid crystal display panel, an electrophoretic display panel, or an electrowetting display panel. In addition, those known in the art may be applied to the configuration of the display device.

Hereinafter, the present invention will be described in more detail through examples. However, the following examples are only for illustrating the present invention, and the scope of the present invention is not limited to the examples.

<Example 1>

1-1. Preparation of first solution - ligand exchange of quantum dots

After dispersing (dissolving) InP quantum dots whose surface is coordinated with a mixed organic ligand such as oleic acid, TOP, TOPO, and trioctylamine, in isobornyl acrylate, in 5 ml of a solution in which the quantum dots are dispersed A first solution is prepared by adding 5 ml of glycol di(3-mercapto propionate). The surface of the quantum dot is substituted with a thiol group while the first solution is stirred at room temperature for 1 hour.

1-2. Preparation of quantum dot-polymer complexes

A second solution is prepared by dissolving 1 part by weight of 2,2'-azobis(2,4-dimethylvaleronitrile) and 0.1 part by weight of methylhydroquinone based on 100 parts by weight of triallyl isocyanurate. After mixing 5 parts by weight of the first solution and 10 parts by weight of the second solution, the mixture was stirred at room temperature for 1 hour, the reactor temperature was set to 65° C., and a quantum dot-polymer composite was prepared through polymerization.

<Example 2>

2-1. Preparation of first solution - ligand exchange of quantum dots

Using the same method as in Example 1-1, a first solution was prepared and the quantum dot surface was substituted with a thiol group.

2-2. Preparation of quantum dot-polymer complexes

A second solution was prepared using the same method as in Example 1-2. After mixing 5 parts by weight of the first solution and 5 parts by weight of the second solution, stirring at room temperature for 1 hour, setting the reactor temperature to 65° C., and feeding 5 parts by weight of the second solution at a flow rate of 0.1 ml/min. , a quantum dot-polymer composite was prepared through a polymerization reaction.

<Example 3>

3-1. Preparation of first solution - ligand exchange of quantum dots

Using the same method as in Example 1-1, a first solution was prepared and the quantum dot surface was substituted with a thiol group.

3-2. Preparation of quantum dot-polymer complexes

A quantum dot-polymer composite was prepared in the same manner as in Example 1-2, except that the second solution was prepared without using the methylhydroquinone used in Example 1-2.

<Example 4>

4-1. Preparation of first solution - ligand exchange of quantum dots

Using the same method as in Example 1-1, a first solution was prepared and the quantum dot surface was substituted with a thiol group.

4-2. Preparation of quantum dot-polymer complexes

A quantum dot-polymer composite was prepared in the same manner as in Example 1-2, except that 5 parts by weight of the first solution and 5 parts by weight of the second solution were used in Example 1-2.

<Example 5>

5-1. Preparation of first solution - ligand exchange of quantum dots

Using the same method as in Example 1-1, a first solution was prepared and the quantum dot surface was substituted with a thiol group.

5-2. Preparation of quantum dot-polymer complexes

A quantum dot-polymer composite was prepared in the same manner as in Example 1-2, except that 10 parts by weight of the first solution and 5 parts by weight of the second solution were used in Example 1-2.

<Comparative Example 1>

The quantum dot ligand exchange reaction proceeded as in Example 1-1, and the quantum dot-polymer complex polymerization reaction of Example 1-2 did not proceed.

<Evaluation Example 1> Evaluation of dispersibility of quantum dots for reactive monomers

Figure 2 shows centrifugation of a sample stirred with a reactive monomer after exchanging a ligand of a quantum dot with a thiol group, and a sample stirred with a reactive monomer without exchanging a ligand of a quantum dot with a thiol group. It can be seen that the ligand-exchanged quantum dots were evenly dispersed in the reactive monomer, but the ligand-exchanged quantum dots were precipitated due to a difference in polarity with the reactive monomer. Through this, it can be seen that the compatibility and miscibility between the quantum dots and the reactive monomer are improved when the ligand of the quantum dot is exchanged with a thiol group and then polymerized with the reactive monomer.

<Evaluation Example 2> Measurement of Viscosity and Molecular Weight of Quantum Dot-Polymer Composite

Quantum dots prepared by the method of Examples 1 to 5 - The viscosity and molecular weight of the polymer composite and the quantum dot of Comparative Example 1 were measured.

Viscosity (cps), 55℃ Mw (g/mol) Example 1 2001 3359 Example 2 2707 1569 Example 3 2371 4948 Example 4 2714 5038 Example 5 2620 2189 Comparative Example 1 4 611

Viscosity was measured at 55°C using a rotational viscometer (Brookfield DV2T Viscometer), and the weight average molecular weight was measured using gel permeation chromatography (Waters GPC system). In this case, the weight average molecular weight includes the quantum dot and the weight of the polymer polymerized on the quantum dot surface.

As shown in Table 1, there is a difference in viscosity and molecular weight depending on the reaction conditions, and the quantum dot-polymer composites of Examples 1 to 5 have a viscosity of 1800 to 2800 cps at 55° C., and a weight average molecular weight (Mw) of 1000 to 6000 g /mol. The weight average molecular weight is the lowest in Example 2, which is a feeding method, and the highest in Example 4, in which no polymerization inhibitor is added.

<Example 6> Preparation of quantum dot composition

Based on the total weight of the quantum dot composition, 3 parts by weight of zinc oxide as a light diffusing agent is dispersed in 30 parts by weight of trimethylolpropane triacrylate (M300, miwon specialty chemical), and hexanediol diacrylate (M200) , miwon specialty chemical) 27 parts by weight, ditrimethylolpropane tetraacrylate (M410, miwon specialty chemical) after mixing 20 parts by weight of the quantum dot prepared in Example 1 - 20 parts by weight of the polymer composite was dispersed to prepare a quantum dot composition.

<Examples 7 to 10> Preparation of quantum dot compositions

Quantum dots in Example 6 - Except for using Examples 2 to 5 instead of Example 1 as the polymer composite, in the same manner as in Example 6 to prepare the quantum dot compositions of Examples 7 to 10.

<Comparative Example 2> Preparation of quantum dot composition

A quantum dot composition was prepared in the same manner as in Example 6, except that the quantum dot according to Comparative Example 1 was used instead of the quantum dot-polymer complex in Example 6.

<Example 11> Preparation of quantum dot optical film

The quantum dot composition prepared in Example 6 was coated to a thickness of 85 μm between two polyethylene terephthalate films (PET, thickness: 100 μm), and then cured by light irradiation at a UV light amount of 80 mJ/cm 2 for 4 seconds to cure the quantum dot-containing layer By forming a quantum dot optical film is prepared.

<Examples 12 to 15> Preparation of quantum dot optical film

A quantum dot optical film was prepared in the same manner as in Example 11, except that the quantum dot composition of Examples 7 to 10 was used instead of Example 6 as the quantum dot composition.

<Comparative Example 3> Preparation of quantum dot optical film

A quantum dot optical film was prepared in the same manner as in Example 11, except that Comparative Example 2 was used instead of Example 6 as the quantum dot composition.

<Evaluation Example 3> Measurement of luminance and color coordinates of quantum dot optical film

After exposing the quantum dot optical film prepared according to Examples 11 to 15 and Comparative Example 3 to light of a blue wavelength, the luminance (Lm) and color coordinates (Cx, Cy) of the quantum dot optical film for each time were calculated using an integrating sphere (PIMACS) , Neolight IS500), and then the luminance and color coordinates of a specific time compared to the initial value were calculated according to Equations 1 to 3. At this time, before light irradiation, the initial luminance (Lm) and initial color coordinates (Cx, Cy) of the quantum dot optical film were set to 100% and 0.000, respectively.

[Equation 1]

(In the above formula,

Lm ₁ is the luminance value of the quantum dot optical film before light irradiation,

Lm ₂ is the luminance value of the quantum dot optical film after light irradiation for a specific time).

[Equation 2]

[Equation 3]

(In the above formula,

Cx1 and Cy1 are the initial color coordinates of the quantum dot optical film before light irradiation,

Cx2 and Cy2 are the color coordinates of the quantum dot optical film after light irradiation for a specific time).

As shown in Table 2, when blue wavelength light was irradiated for 407 hours, luminance and color coordinates decreased. The decrease in luminance was 8% in Example 11, 35% in Example 12, 23% in Example 13, 32% in Example 14, and 27% in Example 15, which is the luminance decrease in Comparative Example 3 less than 51%.

In addition, the decrease in color coordinates was the smallest in Example 11 (Cx -0.004, Cy -0.012), and in Comparative Example 3 (Cx -0.035, Cy -0.076), the decrease was the largest. Through this, although there is a difference depending on the polymerization method of the quantum dot-polymer composite, it was confirmed that the quantum dot optical film including the quantum dot-polymer composite can effectively delay / prevent damage to the quantum dot when exposed to a blue wavelength.

<Evaluation Example 4> Edge penetration evaluation of quantum dot optical film

In Evaluation Example 3, edge penetration was measured using a stereoscopic microscope (Olympus, SZ61) on the side surface of the optical film exposed to light of blue wavelength for 407 hours (in the case of cutting the optical film, the cut surface).

When a quantum dot is degraded by oxygen and/or moisture while exposed to light of a blue wavelength, the quantum dot at the edge does not emit green and/or red light under blue light, and exhibits black lines. The edge penetration values in Table 3 indicate how deeply deteriorated from the cut edge of the quantum dot optical film. In Example 11, the edge penetration was the lowest at 123 μm, and Comparative Example 3 had the highest penetration value of 275 μm. Through this, it was confirmed that the optical films to which the quantum dot-polymer composite was applied had an edge penetration delay effect.

<Evaluation Example 5> Storage stability evaluation of quantum dots-polymer composites

The quantum dot-polymer composite prepared in Example 1 was stored for 14 days at each temperature (-5°C, 25°C, 40°C, 60°C), and then a quantum dot composition was prepared in the same manner as in Example 6, Example 11 After preparing an optical film in the same manner as described above, the luminance and color coordinate changes of the quantum dot optical film were measured.

As shown in Table 4, the quantum dot-polymer composite prepared in Example 1 was stored for 14 days at each temperature, and then the quantum dot optical film and the quantum dot-polymer composite were prepared and initially produced. Brightness and color coordinates of the optical film When measured, there is almost no change. Therefore, it can be confirmed that the quantum dot-polymer composite that has been exposed to high temperature for a long time does not deteriorate.

100: quantum dot optical film
10: quantum dot-containing layer
11: Polymer matrix
12: quantum dot-polymer complex
20: first base film
30: second base film

Claims (16)

(i) preparing a first solution by mixing quantum dots, a dispersing agent, and a thiol compound having at least one thiol group (-SH) at the terminal;
(ii) preparing a second solution comprising a reactive monomer and a polymerization initiator; and
(iii) mixing and polymerizing the first solution and the second solution,
The quantum dot is a group III-V diatomic compound selected from the group consisting of GaN, GaP, GaAs, GaSb, AlN, AlP, AlAs, AlSb, InN, InP, InAs, InSb, and mixtures thereof, part or all of the surface is substituted with an organic ligand,
The dispersant and the reactive monomer are a monomer comprising one of a (meth)acrylic group, a vinyl group, and an allyl group,
The first solution contains quantum dots whose surface is substituted with the thiol group through a ligand exchange reaction between the organic ligand and the thiol group,
The molar ratio of the polymerizable functional group contained in the reactive monomer and the thiol group of the thiol compound is 1: 0.25 to 2,
In step (iii), the thiol compound contained in the first solution reacts with the reactive monomer contained in the second solution with thiolene to form a uniform polymer film,
is a method for producing a quantum dot-polymer complex.
delete According to claim 1,
In the step (i), the mixing ratio of the dispersing agent and the thiol compound is 1: 0.5-5 volume ratio of quantum dots-a method of producing a polymer composite.
delete delete According to claim 1,
The second solution further comprises a polymerization inhibitor.
7. The method of claim 6,
The amount of the polymerization inhibitor is 0.01 to 2 parts by weight based on 100 parts by weight of the reactive monomer.
According to claim 1,
In the step (iii), the mixing ratio of the first solution and the second solution is 1: 0.5-5 weight ratio of quantum dots-polymer composite manufacturing method.
According to claim 1,
The step (iii) is,
preparing a mixed solution by stirring a portion of the first solution and the second solution at room temperature for 0.5 to 2 hours; and
After raising the temperature of the mixed solution to 50 to 100 ℃, the quantum dot-polymer composite manufacturing method comprising the step of supplying the remainder of the second solution at a flow rate of 0.01 to 1 ml / min for polymerization.
Claims 1, 3, and the quantum dot prepared by the method of any one of claims 6 to 9 - a polymer complex; and
A quantum dot composition comprising at least one photopolymerizable monomer.
11. The method of claim 10,
The photopolymerizable monomer is a quantum dot composition comprising a trifunctional or less functional (meth) acrylate monomer and a polyfunctional (meth) acrylate monomer more than tetrafunctional.
12. The method of claim 11,
The mixing ratio of the low-functional (meth) acrylate monomer and the polyfunctional (meth) acrylate monomer is a quantum dot composition in a weight ratio of 90:10 to 10:90.
11. The method of claim 10,
A quantum dot composition further comprising a diffusing agent.
14. The method of claim 13,
The amount of the dispersing agent is 0.1 to 10 parts by weight based on the total weight of the quantum dot composition.
a first base film; and
a second base film; and
a quantum dot-containing layer interposed therebetween;
including,
The quantum dot-containing layer is a cured product obtained by curing the quantum dot composition of claim 10
A quantum dot optical film comprising a.
16. The method of claim 15,
A quantum dot optical film satisfying at least one of the following (i) to (iv) physical properties:
(i) The luminance value retention rate after 180 hours under blue light conditions is 80% or more,
(ii) the luminance value retention rate after 400 hours under blue light condition is 60% or more,
(iii) After 400 hours under blue light conditions, the edge penetration by moisture and oxygen is 250 um or less,
(iv) The luminance value retention rate after storage at -5 to 60°C for 14 days is 95% or more.

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