TW201930547A - Composition comprising a semiconductor light emitting nanoparticle - Google Patents

Abstract

The present invention relates to a composition comprising at least a semiconductor light emitting nanoparticle; and an polymer.

Description

Composition comprising semiconductor light-emitting nanoparticles

The present invention relates to a composition comprising semiconductor light-emitting nanoparticles and an organic phase. The invention further relates to a method of making a layered composite comprising the foregoing composition, an optical medium comprising a layered composition, an optical device comprising the optical medium, and the use of semiconductor light-emitting nanoparticles.

Semiconductor nanocrystals, such as quantum dots, quantum rods, quadrangular pyramids, and the like, are of great interest due to their narrow fluorescence emission as a color converter material in LEDs and displays. Using fluorescent quantum dots for supply, such as a down-converting layer in an LCD, the color filters and color converters directly above the top of the LEDs need to be incorporated into the semiconductor nanocrystals in the thin layer, which will be nanocrystals Provide protection. A polymer film containing quantum dots is one way to obtain a desired thin layer. Various polymers have been used for this purpose, such as acrylates, decanes, decazins, epoxies, polyoxyxides, and the like. In particular, acrylates are used in large quantities in backlight film applications.

Incorporating a quantum dot into such a layer results in a decrease in its quantum yield (QY). This is caused by the aggregation of quantum dots in the solid polymer film and due to chemical procedures that affect the organic molecules attached to the surface of the quantum dots (known as ligands) and cause the ligand to detach from the surface of the quantum dots. Further, when incorporated into a display device, quantum dots containing a polymer film are subjected to elevated temperature, humidity conditions, and high light inflow. These conditions further damage the ligand coverage of the quantum dot surface. Observable results are the degradation of quantum dot performance in the quantum yield (QY) parameter, the shift of the center wavelength (CWL) of the fluorescence curve, and the full width of the half-peak of the fluorescence spectrum (full-width). -half-max, FWHM) changes.

Another disadvantage is that many acrylate polymers are photocurable. This means that the photoinitiator needs to be incorporated into the film before it cures, and then the polymer is illuminated. It is known that this photoinitiator generates a large amount of free radicals during the polymerization process, which can also impair the performance of the quantum dots.

In general, it is an object of the present invention to at least partially overcome at least one of the disadvantages known from the prior art.

Another object of the present invention is to provide an optical medium which preferably exhibits a higher quantum yield per quantum dot per semiconductor light-emitting nanoparticle than the optical media known in the art.

Another object of the present invention is to provide an optical medium having a stable quantum yield over its useful life. Another object of the present invention is to provide an optical medium in which the center wavelength of the fluorescence curve is not displaced during use of the optical medium. Another object of the present invention is to provide a medium in which the FWHM of the fluorescence spectrum does not change over the life of the optical medium. Another object of the present invention is to provide an optical medium in which a quantum dot can be incorporated in a polymer matrix, wherein the polymer matrix is produced by thermal curing.

Another object is to provide less sophisticated improved optics, improved emission chromatography, and stronger light at a given wavelength. Another object is to provide an optical device that consumes less electrical energy but has the same optical output, such as conventional optical devices. Another object of the present invention is to provide an optical device comprising an optical medium which can be combined with a matrix polymer and semiconductor light-emitting nanoparticles, preferably quantum dots, wherein the matrix polymer is produced by thermal curing.

Another object is to provide a composition comprising semiconductor light-emitting nanoparticles, preferably quantum dots, more preferably a plurality of quantum dots, for use on a substrate, which can be used to fabricate layers having quantum dots, wherein Those skilled in the art, with respect to quantum yield (QY), central wavelength (CWL), and full width at half maximum (FWHM) of the fluorescence spectrum, are more stable. Furthermore, it is an object of the present invention to provide semiconductor light-emitting nanoparticles in a composition, preferably quantum dots, more preferably a plurality of quantum dots, wherein the quantum dots are more comparable to those known in the art. Efficient and / or present a higher output. Another object of the present invention is to provide semiconductor light-emitting nanoparticles, preferably quantum dots, more preferably a plurality of quantum dots, which can be incorporated into a matrix polymer produced by thermal curing.

Another object is to provide a method of making a layered composite comprising at least one layer comprising semiconductor light-emitting nanoparticles, preferably quantum dots, more preferably a plurality of quantum dots; the semiconductor light-emitting nanoparticle At least partially coated with a polymer that degrades the efficiency of the quantum yield as small as possible.

It has been discovered that quantum dots sealed in a cross-linked poly(maleic anhydride olefin copolymer), preferably a plurality of quantum dots, unexpectedly provide a solution to some of the foregoing objectives. It has further been found that the (and the like) sealed quantum dots can also be used in matrix polymers produced by thermal curing. Furthermore, it has been discovered that, contrary to the procedures conventional in the prior art, the claimed invention does not require ligand exchange at nanocrystals, such as quantum dots, prior to sealing the quantum dots. Thus, the method of the invention involves fewer chemical steps, i.e., is more efficient. In addition, having its initial ligand, that is, the quantum dots as purchased, exhibits higher potency than their quantum dots with ligand exchange.

A contribution is made to at least one of the above objects by forming the subject matter of the category of the claimed invention. Further contributions are made by the subject matter of the scope of the appended claims of the present invention.

Preferred embodiment
A composition comprising at least the following components:
a) a semiconductor light-emitting nanoparticle, preferably a quantum dot, more preferably a plurality of quantum dots;
b) maleic anhydride olefin copolymer;
c) a polyfunctional amine;
d) an acrylic polymer;
e) an organic phase;
Wherein the maleic anhydride olefin copolymer has at least a first repeating unit and a second repeating unit.
2. The composition of embodiment 1, wherein the first repeat unit and the second repeat unit are different from each other.
3. The composition of any of embodiments 1 or 2, wherein the second repeating unit is based on a linear C10 to C30 1-olefin.
4. The composition of any of the preceding embodiments, wherein the polyfunctional amine is bis(hexamethylene)triamine.
5. The composition of any of the preceding embodiments, wherein the acrylic polymer is selected from the group consisting of poly(methyl methacrylate) and poly(dicyclopentyl acrylate).
6. The composition of any of the preceding embodiments, wherein the semiconductor light-emitting nanoparticle, preferably the quantum dot, more preferably the plurality of quantum dots are at least partially coated with component b.
7. A method of making a layered composite comprising at least the following steps:
(I) providing a substrate;
(II) A composition as in any one of embodiments 1 to 6 is applied to the substrate (I) to form a layer on the substrate.
8. A method of making a layered composite comprising at least the following steps
(A) The mixture phase is produced by at least the following steps:
i) providing a liquid phase comprising at least semiconductor light-emitting nanoparticles, preferably quantum dots, more preferably a plurality of quantum dots;
Ii) adding a liquid phase comprising a maleic anhydride olefin copolymer;
Iii) adding a polyfunctional amine;
Iv) adding an acrylic polymer;
(B) applying the mixture to a substrate to form a layer;
(C) drying the mixture on the substrate;
Wherein the layer comprises at least the semiconductor light-emitting nanoparticle, preferably the quantum dot, more preferably the plurality of quantum dots;
Each of the quantum dots has a shell layer comprising component b.
9. The method of embodiment 8, wherein the layer is a polymeric film.
A layered composite obtainable by the method of any one of embodiments 7 to 9.
11. A layered composite comprising
At least an acrylic polymer; and a substrate;
Wherein the acrylic polymer comprises semiconductor light-emitting nanoparticles, preferably quantum dots, more preferably a plurality of quantum dots;
Wherein the quantum dot, preferably the plurality of quantum dots are at least partially coated with a maleic anhydride olefin copolymer;
Wherein the maleic anhydride olefin copolymer has at least a first repeating unit and a second repeating unit.
The layered composite according to any one of embodiments 10 or 11, wherein the first repeating unit and the second repeating unit of the maleic anhydride olefin copolymer are different from each other.
The layered composite of any one of embodiments 10 to 12, wherein the second repeating unit of the maleic anhydride olefin copolymer is based on a linear C10 to C30 1-olefin.
The layered composite of any one of embodiments 10 to 13, wherein the acrylic polymer is selected from the group consisting of poly(methyl methacrylate) and poly(dicyclopentyl acrylate) .
An optical medium comprising the layered composite of any one of embodiments 10 to 13 or obtainable by the method of any one of embodiments 7 to 8.
16. An optical device comprising the optical medium of embodiment 15.
17. Use of a quantum dot, preferably a plurality of quantum dots coated with a maleic anhydride olefin copolymer for use in improving the quantum yield of the quantum dots.
18. Use of a maleic anhydride olefin copolymer for improving quantum yield of quantum dots.
The use of any of embodiments 17 or 18, wherein the maleic anhydride olefin copolymer is at least partially crosslinked.

A first aspect of the invention is a composition comprising at least the following components:
a) a quantum dot, preferably a plurality of quantum dots;
b) maleic anhydride olefin copolymer;
c) a polyfunctional amine;
d) an acrylic polymer; and
e) an organic phase;
Wherein the maleic anhydride olefin copolymer has at least a first repeating unit and a second repeating unit.

The composition may be of any kind known to those skilled in the art. The composition is a suspension and therefore contains liquid and solid ingredients. An example of a liquid component is an organic phase. Quantum dots are examples of solid components. Each of the additional ingredients of the composition may have a solid or liquid state at room temperature (20 ° C). Each of the other ingredients which are solid at room temperature may be present as a solid in the composition, or at least partially dissolved or formed into a gel by the liquid component of the composition.

The quantum dots that are components of the composition can be any type of quantum dot known to those skilled in the art and believed to be applicable. In the context of the present invention, the quantum dots are semiconductor particles, and more preferably semiconductor nanoparticles. Quantum dots can emit light. Still more preferably, the quantum dots are semiconductor luminescent particles, or semiconductor luminescent nano particles. Quantum dots emit tunable colored glare.

According to the invention, the term "semiconductor" means a material having a conductivity between the conductance of a conductor such as copper and an insulator such as glass at room temperature. Preferably, the conductivity of the semiconducting material increases with temperature.

The term "nanoparticle" means a particle having a size between 0.1 nm and 999 nm, preferably 0.5 nm to 150 nm, more preferably 1 nm to 50 nm. In this context, the term "size" means the average diameter of the longest axis of the particles mentioned. The average diameter of a certain particle was calculated using an arithmetic mean based on measurements of 100 such individual particles in a TEM image produced by a Tecnai G2 Spirit Twin T-12 Transmission Electron Microscope (TEM).

The term "luminescence" refers to the property of a material or object that emits light having a wavelength of from 250 nm to 800 nm, such as an incident beam of light of a particular wavelength or a particular wavelength range, after external activation.

Thus, the term "semiconductor luminescent nanoparticle" refers in this context to a luminescent material having a size between 0.1 nm and 999 nm, preferably 1 nm to 150 nm, more preferably 3 nm to 50 nm; The temperature conductivity is between the conductivity of a conductor (such as copper) and an insulator (such as glass). Preferably, the semiconductor is a material whose electrical conductivity increases with temperature and is between 0.1 nm and 999 nm. It is preferably from 0.5 nm to 150 nm, more preferably from 1 nm to 50 nm.

According to the invention, the quantum dot comprises a core and at least one shell layer. The shell layer is made of at least one shell material. The shell material at least partially covers the core, preferably completely covering the core.

In the present invention, it is particularly preferred that the core material is selected from the group consisting of CdS, CdSe, CdTe, ZnS, ZnSe, ZnSeS, ZnTe, ZnO, GaAs, GaP, GaSb, HgS, HgSe, HgSe, HgTe, InAs, InP, InPS, InPZnS, InPZn, InPZnSe, InCdP, InPCdS, InPCdSe, InGaP, InGaPZn, InSb, AlAs, AlP, AlSb, Cu2S, Cu2Se, CuInS2, CuInSe2, Cu2(ZnSn)S4, Cu2(InGa)S4, A combination of TiO2 alloy and two or more of them.

In a preferred embodiment of the invention, the core comprises at least one element of Group 13 of the Periodic Table of the Elements, and at least one element of Group 15 of the Periodic Table of the Elements. Preferably, In is selected from the group 13 elements, and P is selected from the group 15 elements. Still more preferably, the core of the quantum dot can be represented by the following formula (I) or formula (I ́).
In _1-x Ga _x Zn _z P (I)
Where 0≦x≦1, 0≦z≦1. Preferred examples of the core according to formula I are InP, In _x Zn _z P, and In _{1 - x} Ga _x P.

It will be readily understood by those skilled in the art that counterions are present in or around the core, and thus formula (I) is electrically neutralized.
In _1-x-2/3z Ga _x Zn _z P (I ́)
Where 0≦x≦1, 0≦z≦1. Preferred examples of the core according to formula I' are InP, In _{1 - 2 / 3z} Zn _z P or In _{1 - x} Ga _x P.

In the case where In _{1 - 2 / 3z} Zn _z P, x is 0, and 0˂z≦1, the Zn atom may be located directly above the surface of the core or alloyed with InP. The ratio between Zn and In may be in the range of 0.05 to 5, preferably in the range of 0.07 to 1.

According to the present invention, the type of the core shape of the semiconductor light-emitting nanoparticles and the shape of the semiconductor light-emitting nanoparticles to be synthesized are not particularly limited. For example, spherical, elongated, star-shaped, polyhedral, square, quadrangular, tetrahedral, flake, conical and irregular cores and/or semiconducting luminescent nanoparticles can be synthesized.

In some embodiments of the invention, the core has an average diameter ranging from 1.5 nm to 3.5 nm.

The shell layer of the quantum dot of the present invention may comprise or consist of a first element of Group 12 of the Periodic Table of the Elements and a second element of Group 16 of the Periodic Table of the Elements. Preferably, the first element is Zn. Preferably, the second element is selected from the group consisting of: S, Se, and Te.

Preferably, the shell layer is represented by the following formula (II).
ZnS _x Se _y Te _z , (II)
Where 0 ≤ x ≤ 1, 0 ≤ y ≤ 1, 0 ≤ z ≤ 1, and x + y + z = 1. In a preferred embodiment, the shell layer is selected from the group consisting of ZnSe, ZnS _x Se _y , ZnSe _y Te _z and ZnS _x Te _z .

In another preferred embodiment of the invention, the shell layer is an alloyed shell layer or a graded shell layer. Preferably, the graded shell layer is selected from the group consisting of ZnS _x Se _y , ZnSe _y Te _z and ZnS _x Te _z , and still more preferably ZnS _x Se _y .

The ratio of y/x is preferably greater than 0.5, more preferably greater than 1, and even more preferably greater than 2. The ratio of y/z is preferably greater than 1 and more preferably greater than 2 and even more preferably greater than 4.

In another preferred embodiment of the invention, the quantum dot further comprises a second shell layer that at least partially covers, preferably completely covers, the first shell layer. The second shell layer may comprise or consist of a third element of Group 12 of the Periodic Table of the Elements and a fourth element of Group 16 of the Periodic Table of the Elements. Preferably, the third element is Zn. Preferably, the fourth element is S, Se or Te. More preferably, the fourth element is not the same as the second element.

In another preferred embodiment of the present invention, the second shell layer is represented by the following formula (II ́).
ZnS _x Se _y Te _z , - (II ́)
Wherein the formula (II ́), 0 ≤ x ≤ 1, 0 ≤ y ≤ 1, 0 ≤ z ≤ 1 and x + y + z = 1, preferably, the shell layer is ZnSe, ZnS _x Se _y , ZnSe _y Te _z or ZnS _x Te _z , with the proviso that the shell layer is different from the second shell layer.

In some embodiments of the present invention, the second shell layer may be an alloy shell layer or a graded shell layer. Preferably, the graded shell layer is ZnS _x Se _y , ZnSe _y Te _z or ZnS _x Te _z , more preferably Ground, which is ZnS _x Se _y .

In some embodiments of the invention, the quantum dots may further comprise one or more additional shell layers on the second shell layer and thus have a multi-shell layer.

According to the invention, the term "multi-shell" means a stacked shell composed of three or more than three shell layers.

For example, the third shell layer and the fourth shell layer or, optionally, the fifth shell layer may be selected from one of the following sequences: CdSe/CdS, CdSeS/CdZnS, CdSeS/CdS/ZnS, ZnSe/CdS, CdSe/ ZnS, InP/ZnS, InP/ZnSe, InP/ZnSe/ZnS, InZnP/ZnS, InZnP/ZnSe, InZnP/ZnSe/ZnS, InGaP/ZnS, InGaP/ZnSe, InGaP/ZnSe/ZnS, InZnPS/ZnS, InZnPS/ ZnSe, InZnPS/ZnSe/ZnS, ZnSe/CdS, ZnSe/ZnS, or a combination of any of these sequences may be used. Preferably, InP/ZnS, InP/ZnSe, InP/ZnSe _x S _{1 - x} , InP/ZnSe _x S _{1 - x} /ZnS, InP/ZnSe/ZnS, InZnP/ZnS, InP/ZnSe _x Te _{1 - x} /ZnS, InP/ZnSe _x Te _{1 - x} , InZnP/ZnSe, InZnP/ZnSe/ZnS, InGaP/ZnS, InGaP/ZnSe, InGaP/ZnSe/ZnS.

In some embodiments of the invention, the surface of the quantum dots can be covered by coating one or more types of surface ligands. Without wishing to be bound by theory, it is believed that such surface ligands may make the nano-sized phosphor material more readily dispersible in the solvent.

Examples of commonly used surface ligands include phosphines and phosphine oxides such as trioctylphosphine oxide (TOPO), trioctylphosphine (TOP) and tributylphosphine (TBP); phosphonic acids such as dodecyl Phosphonic acid (DDPA), tridecylphosphonic acid (TDPA); amines such as oleylamine, dodecylamine (DDA), tetradecylamine (TDA), hexadecylamine (HDA) and ten Octaalkylamine (ODA), oleylamine (OLA), 1-octadecene (ODE); mercaptans such as hexadecanethiol and hexanethiol; mercaptocarboxylic acid such as mercaptopropionic acid and mercaptodecane Acid; formic acid, such as oleic acid, stearic acid, myristic acid; acetic acid and combinations of any of these ligands. Further, the ligand may include Zn-oleate, Zn-acetate, Zn-myristate, Zn-stearate, Zn-laurate, and other Zn-formate. Further, preferably, polyethylenimine (PEI) can be used.

The maleic anhydride olefin polymer of the composition of the present invention may be of any kind known to those skilled in the art and considered suitable for use in the practice of the present invention. More specifically, the maleic anhydride olefin copolymer has at least a first repeating unit and a second repeating unit, and the first repeating unit is different from the second repeating unit. The repeating unit is formed by the polymerization of one or more monomers. The first repeating unit is formed from maleic anhydride in the maleic anhydride olefin polymer. The maleic anhydride olefin copolymer forms an outer polymeric shell that at least partially, preferably completely, covers the quantum dots, cores, and shell layers.

The second repeating unit may be formed of a linear or branched olefin, and more preferably a linear or branched 1-olefin.

According to the invention, the term "1-olefin" means an alpha olefin.

Preferably, the alpha olefin is represented by the following chemical formula.
CH ₂ =CH ₂ -(CH ₂ ) _n -CH ₃
Wherein n is an integer from 7 to 27.

In another preferred embodiment, the second repeating unit is formed from a linear 1-olefin. Still more preferably, the linear 1-olefin has a substituted or unsubstituted C1 to C30 radical, preferably a C4 to C26 radical, such as a C10 to C20 radical, and more preferably a C15 to C20 radical. The C4 radical represents a carbon chain of 4 carbons, and the resulting olefin has a carbon chain of 6 carbons. The C20 radical represents a carbon chain of 20 carbons, and the resulting olefin has a carbon chain of 22 carbons. Therefore, the 1-olefin having a C4 linear radical is a 1-olefin having a radical having 4 carbon atoms in one chain. In this regard, the unsubstituted example is 1-hexene. Similarly, the 1-olefin having a linear and unsubstituted C16 radical is 1-octadecene. Preferred examples of 1-olefins are 1-decene, 1-dodecene, 1-tetradecene, 1-hexadecene, 1-octadecene and 1-eicosene.

In a preferred embodiment of the present invention, the second repeating unit is represented by the following chemical formula (IIIa) or chemical formula (IIIb).

Wherein n is an integer from 7 to 27, and m is an integer of 1 or greater.

As in the present invention, when two or more than two different monomers are polymerized, two or more repeating units can be found in the resulting polymer. Two or more than two different repeating units can be configured into the sequences in the resulting polymer in a variety of ways. For example, it can be distributed statistically in the polymer chain such that the segments of the same repeating unit (block copolymer) are staggered, forming segments of the same repeating unit (block copolymer), and the like.

In a preferred embodiment of the invention, the maleic anhydride olefin polymer has two repeating units, one repeating unit derived from maleic anhydride and the second repeating unit derived from linear 1-olefin. Still more preferably, the maleic anhydride olefin polymer of the present invention has two repeating units wherein the repeating units are staggered in the polymer chain of the polymer.

In a preferred embodiment, the maleic anhydride polymer of the composition of the present invention has a range of from 10,000 to 500,000 g/mol, preferably from 15,000 to 200,000 g/mol, for example from 20,000 to 150,000 g/ the mol or 20,000 to 100,000 g / mol range, and more preferably a number in the 30,000 to 50,000 g / mol range are polymer weight (M _n). The molecular weight is usually indicated on a commercial sample.

The polyfunctional amines of the compositions of the present invention can be any polyfunctional amine known to those skilled in the art and believed to be suitable for use in the practice of the present invention. Examples of polyfunctional amines are methylene diamine, ethylene diamine, hexamethylene diamine, and more preferably bis(hexamethylene) triamine.

The acrylic polymer of the compositions of the present invention can be any type of acrylic polymer known to those skilled in the art and believed to be suitable for use in the practice of the present invention. Preferred examples of the acrylic polymer are poly(methyl methacrylate) (PMMA) and poly(dicyclopentanyl acrylate).

In a preferred embodiment, the acrylic polymer of the composition of the present invention has a range of from 50,000 to 200,000 g/mol, such as from 70,000 to 170,000 g/mol, and more preferably from 100,000 to 150,000 g/mol. The number average polymer weight ( M _n ) within the range. The molecular weight is usually indicated on a commercial sample.

The organic phase of the compositions of the present invention can be any organic phase known to those skilled in the art and believed to be suitable for use in the practice of the present invention. Suitable organic phases can be aprotic or polar, or aprotic and polar. Examples of preferred organic phase components are toluene, hexane, heptane, and still more preferably chloroform, or a combination of two or more thereof. In a preferred embodiment, the organic phase is formed from a single component selected from the components mentioned above.

In another preferred embodiment of the invention, the quantum dots are at least partially coated with component b. Preferably, the quantum dots are coated with component b in a coating range of 10 to 100%, preferably 20 to 100% or 50 to 90%, and more preferably in the range of 60 to 100%, for example 70 To 99% or 80 to 98%, all % are based on the amount of quantum dot surface over which component b overlaps the quantum dots. Still more preferably, the quantum dots are all coated with component b.

A second aspect of the invention is a method of making a layered composite comprising at least the following steps:
(I) providing a substrate;
(II) A composition as described in any of the embodiments is coated on a substrate (I) to form a layer on the substrate.

In this context, a layered composite refers to an object comprising at least a substrate and at least one layer. The layered composite may have more than one layer, such as 2, 3, 4, 5, 6, 7, 8, 9, or 10 layers. These layers may all be located on one side of the substrate. For some substrates, one or more of the layers may be located on one surface of the substrate that avoids the surface on which the layer of the invention is formed. Furthermore, the layered composite may have two or more layers formed from one or more of the same or different compositions as mentioned above.

Providing the substrate can be performed by any means known to those skilled in the art and believed to be applicable to render the invention functional. Preferably provided by mounting on a substrate holder; placed on a rotating disk, such as a spin coater.

Suitable substrates can be of any type known to those skilled in the art and which are believed to be applicable to render the invention work. A preferred example of a substrate is a piece of glass and a layered structure.

The coating as described above can be applied by any means known to those skilled in the art and believed to be applicable to render the invention functional, the composition being a quantum dot, maleic anhydride olefin copolymer. A combination of a polyfunctional amine, an acrylic polymer, and an organic phase, each of which is selected as described above. Preferred coating methods include spin coating and dip coating.

After the composition has been applied to the substrate, a layer is formed therein which can be subjected to a heat treatment to stabilize it as an auxiliary measure. Any manner of heat treatment known to those skilled in the art and believed to be applicable to render the invention effective can be employed. Among these heat treatment methods, heat treatment by hot gas flow and heating of the layer in an oven are preferred. The heat treatment can affect the evaporation of the solvent and the polymerization and/or crosslinking reaction of one or more of the components. By such heat treatment, a stable layer containing the aforementioned quantum dots is obtained on the substrate.

A third aspect of the invention is a method of making a layered composite comprising the following steps
(A) making the mixture at least by the following steps:
i) providing a liquid phase comprising quantum dots, preferably a plurality of quantum dots;
Ii) adding a liquid phase comprising a maleic anhydride olefin copolymer;
Iii) adding a polyfunctional amine;
Iv) adding an acrylic polymer;
(B) applying the mixture to a substrate to form a layer; wherein the layer formed may be a polymer film;
(C) drying the mixture on the substrate;
Where the layer comprises quantum dots;
Each of the quantum dots has a shell layer comprising a maleic anhydride olefin copolymer.

The same terms and definitions as those previously described share the same meaning and may have the same or at least similar preferred embodiments. However, the terms described in this aspect need not be implemented in exactly the same way, as previously proposed. Consistent with the foregoing, reference is made to the above definitions, preferred embodiments and ranges for quantum dots, maleic anhydride olefin copolymers, polyfunctional amines, and acrylic polymers.

In step ii), a liquid phase comprising a maleic anhydride polymer is added to the liquid phase of step i). The liquid phase may comprise any type of liquid or organic phase known to those skilled in the art and believed to be suitable for distributing quantum dots therein. Reference is made to the description of suitable solvents and preferred embodiments as described in the first aspect of the invention. In this regard, the preferred organic phase is chloroform.

In step iii), a polyfunctional amine is added to the combined liquid phase of steps i) and ii), which may be added neat or in diluted form. Preferably, a pure polyfunctional amine is added. More preferably, the polyfunctional amine is added dropwise. When a polyfunctional amine is added, a temperature between room temperature or between 0 ° C and 30 ° C, more preferably between 10 ° C and 30 ° C or between 20 ° C and 30 ° C is preferred. Reference is made to the findings relating to polyfunctional amines, as described in the first aspect of the invention, especially with respect to preferred choices and more preferred embodiments of polyfunctional amines.

In step iv), the acrylic acid polymer is added to the combination from steps i), ii) and iii) by stirring the components of steps i) to iv) to obtain a mixture of step (A). Stirring can be performed individually in each of the aforementioned steps i) to iv). In a preferred embodiment, the liquid phase is provided with agitation and agitation is maintained in each of the other steps ii), iii) and iv). Furthermore, agitation intervals can be implemented between each of steps i) to iv). This achieves liquid phase formation step i. or allows the combination of the liquid phase from step a. and one or more other ingredients to be allowed to stand and/or homogenize prior to the addition of another component.

The mixture in step (A) can be produced under inert conditions at room temperature and elevated temperature, and/or under standard pressure, elevated or reduced pressure, all conditions being referenced to the conditions in the mixing vessel . Preferably, based on the absolute scale (0 kPa = absolute vacuum), step (A) is operated under inert conditions at a temperature in the range of 0 to 100 ° C and at an ambient pressure of 1 bar (10 13 hPa). Stirring can be achieved by rotating the mixing vessel or by inserting the rotary mixer into the static mixing vessel. Preferred modes of operation include the use of a flask as a static mixing vessel and the use of a stirrer.

Step (B) refers to the same procedure as step (II) of the second aspect of the present invention. Preferred embodiments thereof are also preferred embodiments herein.

Step (C) refers to a procedure as described in the second aspect of the invention for heat treatment selected as appropriate. Preferred embodiments thereof are also preferred embodiments herein.

A fourth aspect of the invention is a layered composite obtainable by a method as described in the third aspect of the invention or by any of its embodiments. As already mentioned, the preferred layered composite comprises a substrate and at least one layer, wherein the at least one layer is a polymeric film.

In a preferred embodiment, the layer has a thickness of 50 to 2000 nm, such as a random thickness of 100 to 1500 nm or 250 to 1250 nm. The thickness of this layer is preferably in the range of 500 to 1200 nm. The thickness of the layer is determined in a direction perpendicular to the plan created by the surface of the substrate adjacent to the layer and the layers, respectively. The thickness of the layer can be determined by cutting the swatch and analyzing the layer perpendicular to the kerf through the substrate using scanning electron microscopy (SEM). More preferably, two or more layers may be part of a layered composite.

A fifth aspect of the invention is a layered composite comprising
a) acrylic polymer; and
b) the substrate;
Wherein the acrylic polymer comprises quantum dots, preferably a plurality of quantum dots;
Wherein the quantum dot is at least partially coated with a maleic anhydride olefin copolymer;
Wherein the maleic anhydride olefin copolymer has at least a first repeating unit and a second repeating unit.

The preferred embodiment of the fifth aspect of the invention, in detail the acrylic polymer, substrate, quantum dots, coating thereof and maleic anhydride olefin copolymer, is as described above, and is detailed It is the same as those described in relation to the first and fourth aspects of the invention. The acrylic polymer in α) is preferably obtained from a composition according to one of the first aspects of the invention or an embodiment thereof, and/or by the second and third aspects of the invention and One of the methods of the examples was obtained.

In a preferred embodiment of the invention, the first repeating unit and the second repeating unit of the maleic anhydride olefin copolymer are different from each other, as described above. In another preferred embodiment, the maleic anhydride olefin copolymer is crosslinked due to the reaction of the maleic anhydride functional group with the amine group of one or more polyfunctional amines.

In another preferred embodiment, the layered composite has a maleic anhydride olefin copolymer having a first repeating unit and at least a second repeating unit, wherein the first repeating unit is self-polymerizing maleic anhydride And obtained, and wherein the second repeating unit of the maleic anhydride olefin copolymer is based on a linear 1-olefin. In this regard, the preferred and other examples are the same as the maleic anhydride olefin polymer described in the first aspect of the invention.

In another preferred embodiment, the acrylic polymer of the layered composite is selected from the group consisting of poly(methyl methacrylate) (PMMA) and poly(dicyclopentanyl acrylate).

A sixth aspect of the invention is an optical medium comprising a layered composite as described above or as obtained by the aforementioned method. The optical medium can be an optical sheet, such as a color filter, a color conversion film, a remote phosphor tape, or another film or filter.

A seventh aspect of the invention is an optical device comprising the optical medium. In some embodiments of the present invention, the optical device may be selected from the group consisting of a liquid crystal display device (LCD), an organic light emitting diode (OLED), a backlight unit for an optical display, and a light emitting diode. Devices (LEDs), microelectromechanical systems (hereinafter "MEMS"), electrowetting displays, electrophoretic displays, lighting devices, and solar cells.

An eighth aspect of the invention is the use of quantum dots coated with a maleic anhydride olefin copolymer for improving the quantum yield of quantum dots.

A ninth aspect of the invention is the use of a maleic anhydride olefin copolymer for improving the quantum yield of quantum dots.

In a preferred embodiment of the foregoing eighth and ninth aspects, the maleic anhydride olefin copolymer is at least partially crosslinked. Still more preferably, the maleic anhydride olefin copolymer is crosslinked by the use of a polyfunctional amine, preferably selected from those mentioned above in describing the first aspect of the invention.

Figure 1 shows experimental data obtained from the measurement of quantum yield (QY) of the following examples. The normalized quantum yield (nQY) (arbitrary units) is shown to be tracked over time (days). nQY is calculated by dividing the y value at time x (y _x ) of each measurement by the initial y value at time = 0 (y ₀ ). Depending on the instance, x typically has a value between 0 and 68. As a result, nQY represents a relative decrease in quantum yield over time. A higher nQY indicates better performance. All examples show a decrease in nQY over time. Compared to other examples, the decrease in nQY over time is less pronounced for Example 1. Most other examples show a decrease of nQY of 0.4 or higher in the first 10 days, while nQY of Example 1 is reduced by about 0.1 in the same time. Additionally, Example 1 shows that nQY is about 0.67 at time >= 50 days, while Comparative Example 5 shows that nQY is about 0.5 at time >= 50 days, and all other instances <= 0.4. Thus, Example 1 has much better overall performance than the comparative example.

Figure 2 shows a quantum dot 1 with ligand 2 . The quantum dot 1 may include a core (striped region) and a shell layer (around the line). This quantum dot 1 is covered by a polymer 4 . Polymer 4 is also referred to as an "external polymer shell." The polymer molecules of polymer 4 may be linked by a linking group 5 . 3 represents the interaction and/or bonding between the polymer 4 and the quantum dot 1 .

testing method
Quantum yield <br/>The quantum yield (QY), center wavelength (CWL, also referred to as: peak) is performed on a Hamamatsu Quantaurus QY Absolute PL quantum yield spectrometer C11347-11 (hereinafter referred to as "Hamamatsu Quantaurus"). Measurement of wavelength) and full width at half maximum (FWHM, also referred to as: peak band). Samples were prepared by depositing a solution on a cleaned 3 cm x 3 cm glass substrate and spin coating the solution at 1000 rpm for 30 seconds. The resulting layer was dried at 120 ° C for 8 minutes under argon. The glass substrate was cut into pieces of 1 cm x 1 cm. The excitation wavelength was set to 450 nm. The photoluminescence curve obtained from the measurement of the sample is integrated in the range of 500 nm to 800 nm.

Layer Thickness : The sample was scratched on the back side and then cut into two pieces.

The damaged edge was studied by scanning electron microscopy (SEM).

Examples <br/> by examples and figures illustrate the invention, examples and drawings do not imply any limitation of the present invention in more detail hereinafter. Moreover, the schematic representations are not to scale.

Example 1
5 mL of quantum dot solution (50 mg/mL in chloroform) and 5 mL of poly(maleic anhydride-alternate-octadecene) solution (purchased from Sigma-Aldrich, Saint Louis, USA, product number 419117, M _n = 30,000 to 50,000 g / mol, an acid value of 301 to 315 mg KOH / g) (175 mg / mL, in chloroform) and mixed at room temperature (20 ℃) under argon Stir under night. Next, 5 mL of a cross-linking agent (bis(hexamethylene)triamine) solution (8.5 mg/mL in chloroform) was added dropwise under argon and stirred at room temperature under argon. 1 hour. Next, 3 mL of poly(dicyclopentyl acrylate) was added to the solution and the solvent (chloroform) was removed by a rotary evaporator. The solution was deposited on a cleaned 3 x 3 cm glass substrate and spin coated at 1000 rpm for 30 seconds. The layer was dried at 120 ° C for 8 minutes under argon. The glass substrate was cut into 1 x 1 cm pieces and measured by Hamamatsu Quantaurus. Trichloromethane is always analytical grade.

The measurements from the samples from Example 1 were compared to comparative samples using a commercial dispersant (BYK-163, available from BYK-Chemie GmbH, Wesel, Germany) instead of cross-linked poly(maleic anhydride). Alternate-octadecene).

Observations : The layer of Example 1 exhibited a higher quantum yield than the layer of the comparative example, especially after a longer test period, and no cross-linked poly(maleic anhydride-alternate-octadecene) was used in the comparative example.

Comparative example 1
Mix 3 mL of the quantum dot solution (50 mg/mL in chloroform) with 9 mL of BYK-163 solution (9.3 mg/mL in chloroform) and stir overnight at room temperature under argon. . Next, 0.81 mL of poly(dicyclopentyl acrylate) available from Hitachi Chemical Co., Ltd., Japan, was added to the solution and the solvent (chloroform) was removed by a rotary evaporator. The solution was deposited on a cleaned 3 x 3 cm glass substrate and spin coated at 1000 rpm for 30 seconds. The layer was dried at 120 ° C for 8 minutes under argon. The glass substrate was cut into 1 x 1 cm pieces and measured by Hamamatsu Quantaurus.

Comparative example 2
2 mL of the quantum dot solution (50 mg/mL in chloroform) was mixed with 0.5 mL of poly(dicyclopentyl acrylate) and the solvent (chloroform) was removed by a rotary evaporator. The solution was deposited on a cleaned 3 x 3 cm glass substrate and spin coated at 1000 rpm for 30 seconds. The layer was dried at 120 ° C for 8 minutes under argon. This layer is not really uniform and looks extremely uneven. The glass substrate was cut into 1 x 1 cm pieces and measured by Hamamatsu Quantaurus.

Comparison examples 3 to 5
Mix 5 mL of the quantum dot solution (50 mg/mL in chloroform) with 5 mL of chloroform BYK-163 solution at a concentration below BYK-163 in chloroform:

It was stirred overnight at room temperature under argon. Next, poly(maleic anhydride-alternate-octadecene) (175 mg/mL in chloroform) was added dropwise to the solution:

In Comparative Examples 3 and 5, the amount of PMAO was reduced by further adding chloroform.

The solutions were then stirred at room temperature under argon for the entire weekend. Next, a cross-linking agent (bis(hexamethylene)triamine) solution (19 mg/mL in chloroform) was added dropwise.

In Comparative Examples 3 and 5, the amount of the crosslinking agent was reduced by further adding chloroform.

It was stirred overnight at room temperature under argon. Next, 2.5 mL of poly(dicyclopentanyl acrylate) purchased from Hitachi was added to the solution and the solvent (chloroform) was removed by a rotary evaporator. The solution was deposited on a cleaned 3 x 3 cm glass substrate and spin coated at 1000 rpm for 30 seconds. The layer was dried at 120 ° C for 8 minutes under argon. The glass substrate was cut into 1 x 1 cm pieces and measured by Hamamatsu Quantaurus. The measurement results were recorded for 68 days. The table shows the selected values after 6.20 ± 1 and 62 ± 1 days.

1‧‧ ‧ quantum dots

2‧‧‧ligand

3‧‧‧Interactions and/or Bonding

4‧‧‧ polymer

5‧‧‧Connecting group

Figure 1 shows a graph of experimental normalized quantum yield (nQY) over time.

Figure 2 shows polymer coated quantum dots.

Claims (19)

A composition comprising at least: a) a semiconductor light-emitting nanoparticle, preferably a quantum dot; b) maleic anhydride olefin copolymer; c) a polyfunctional amine; d) acrylic polymer; and e) organic phase; Wherein the maleic anhydride olefin copolymer has at least a first repeating unit and a second repeating unit. The composition of claim 1, wherein the first repeating unit and the second repeating unit are different from each other. The composition of any one of claims 1 or 2, wherein the second repeating unit is based on a linear C10-C30 1-olefin. The composition of claim 1 or 2, wherein the polyfunctional amine is bis(hexamethylene)triamine. The composition of claim 1 or 2, wherein the acrylic polymer is selected from the group consisting of poly(methyl methacrylate) and poly(dicyclopentyl acrylate). The composition of claim 1 or 2, wherein the semiconductor light-emitting nanoparticle, preferably the quantum dot, is at least partially coated with component b. A method of making a layered composite comprising at least the following steps: (I) providing a substrate; (II) A composition according to any one of claims 1 to 6 is coated on the substrate (I) to form a layer on the substrate. A method of making a layered composite comprising the following steps (A) The mixture phase is produced by at least the following steps: i) providing a liquid phase comprising at least semiconductor light-emitting nanoparticles, preferably quantum dots; Ii) adding a liquid phase comprising a maleic anhydride olefin copolymer; Iii) adding a polyfunctional amine; Iv) adding an acrylic polymer; (B) applying the mixture to a substrate to form a layer; (C) drying the mixture on the substrate; Wherein the layer comprises the nanoparticle; Each of the nanoparticles has a shell layer comprising the maleic anhydride olefin copolymer. The method of claim 8, wherein the layer is a polymeric film. A layered composite obtainable by the method of any one of claims 8 to 9. a layered composite comprising At least acrylic polymer; and Substrate Wherein the acrylic polymer comprises semiconductor light-emitting nanoparticles, preferably quantum dots; Wherein the semiconductor light-emitting nanoparticle, preferably the quantum dot is at least partially coated with a maleic anhydride olefin copolymer; Wherein the maleic anhydride olefin copolymer has at least a first repeating unit and a second repeating unit. The layered composite according to any one of claims 10 or 11, wherein the first repeating unit and the second repeating unit of the maleic anhydride olefin copolymer are different from each other. The layered composite of claim 10 or 11, wherein the second repeating unit of the maleic anhydride olefin copolymer is based on a linear C10 to C30 1-olefin. The layered composite of claim 10 or 11, wherein the acrylic polymer is selected from the group consisting of poly(methyl methacrylate) and poly(dicyclopentyl acrylate). An optical medium comprising the layered composite of any one of claims 10 to 14 or obtainable by the method of claim 8. An optical device comprising the optical medium of claim 15. A semiconductor light-emitting nanoparticle, preferably a quantum dot, coated with a maleic anhydride olefin copolymer for improving the quantum yield of the nanoparticle. A use of a maleic anhydride olefin copolymer coating for improving the quantum yield of the nanoparticle. The use of any one of claims 17 or 18, wherein the maleic anhydride olefin copolymer is at least partially crosslinked.