WO2019038731A1

WO2019038731A1 - Composition comprising cross-linked quantum dots

Info

Publication number: WO2019038731A1
Application number: PCT/IB2018/056453
Authority: WO
Inventors: Changmin Lee; Hyunjin Kang; Namhun Kim; DaeKyung KIM; Heeyeop Chae; Seongwon Kim; Jong Woo Lee; Soonyoung HYUN; Kahee SHIN; Sunyoung Lee; Jeongmin LIM; Chunim LEE
Original assignee: SABIC Global Technologies BV
Current assignee: SABIC Global Technologies BV
Priority date: 2017-08-25
Filing date: 2018-08-24
Publication date: 2019-02-28
Anticipated expiration: 2020-02-25

Abstract

A composition includes a cross-linked quantum dot nanoparticle matrix, the cross- linked quantum dot nanoparticle matrix including a plurality of nanoparticle quantum dots cross-linked by ligands. The ligands include one or more various compounds, including but not limited to one or more compounds including an isocyanate group or an isothiocyanate group and one or more compounds including at least two alcohol groups, at least two thiol groups or a combination thereof. In some aspects the ligands are selected so as to minimize or prevent agglomeration of quantum dots and ensure that the plurality of nanoparticle quantum dots in the cross-linked quantum dot nanoparticle matrix are spaced apart from each other by at least about 10 nanometers, which minimizes or prevents Forster Resonance Energy Transfer between neighboring quantum dots. The resulting cross-linked quantum dot nanoparticle matrix has enhanced optical properties as compared to conventional quantum dot films.

Description

COMPOSITION COMPRISING CROSS-LINKED QUANTUM DOTS

FIELD OF THE DISCLOSURE

[0001] The present disclosure relates to a composition including a cross-linked quantum dot nanoparticle matrix, and in particular to a composition in which the quantum dot nanoparticle matrix is cross-linked by ligands.

BACKGROUND OF THE DISCLOSURE

[0002] Nanoparticles in a polymer matrix are easily aggregated in the matrix due to their high surface energy. Once formed, nanoparticle aggregates are difficult to disrupt. In addition, nanoparticle aggregates have a tendency to grow in size.

[0003] When aggregation occurs in quantum dot nanoparticles in display applications, the aggregates reduce the quantum yield of the quantum dot nanoparticles by causing energy transfer between neighboring quantum dots aggregated in the matrix. Dexter energy transfer (DET) occurs between quantum dot nanoparticles spaced less than about 1 nanometer (nm) from each another, and Forster resonance energy transfer (FRET) occurs between quantum dot nanoparticles spaced from about 1 nm to about 10 nm from each other.

[0004] These and other shortcomings are addressed by aspects of the present disclosure.

BRIEF DESCRIPTION OF THE FIGURES

[0005] In the drawings, which are not necessarily drawn to scale, like numerals may describe similar components in different views. Like numerals having different letter suffixes may represent different instances of similar components. The drawings illustrate generally, by way of example, but not by way of limitation, various aspects discussed in the present document.

[0006] FIG. 1 illustrates a portion of a quantum dot nanoparticle matrix 100 according to an aspect of the disclosure.

SUMMARY

[0007] Aspects of the disclosure relate to a composition including a cross-linked quantum dot nanoparticle matrix, the cross-linked quantum dot nanoparticle matrix including a plurality of nanoparticle quantum dots cross-linked by ligands. The ligands include one or more various compounds, including but not limited to one or more compounds including an isocyanate group or an isothiocyanate group and one or more compounds including at least two alcohol groups, at least two thiol groups or a combination thereof. In some aspects the ligands are selected so as to minimize or prevent agglomeration of quantum dots and ensure that the plurality of nanoparticle quantum dots in the cross-linked quantum dot nanoparticle matrix are spaced apart from each other by at least about 10 nanometers, which minimizes or prevents Forster Resonance Energy Transfer between neighboring quantum dots. The resulting cross-linked quantum dot nanoparticle matrix has enhanced optical properties as compared to conventional quantum dot films.

[0008] Aspects of the disclosure further relate to methods for making a cross-linked quantum dot nanoparticle matrix, the cross-linked quantum dot nanoparticle matrix including a plurality of nanoparticle quantum dots cross-linked by ligands. The ligands include one or more various compounds, including but not limited to one or more compounds including an isocyanate group or an isothiocyanate group and one or more compounds including at least two alcohol groups, at least two thiol groups or a combination thereof. The method includes combining the plurality of nanoparticle quantum dots and ligands, and heating the plurality of nanoparticle quantum dots and ligands to cure the composition and form the cross-linked quantum dot nanoparticle matrix.

DETAILED DESCRIPTION

[0009] The present disclosure can be understood more readily by reference to the following detailed description of the disclosure and the Examples included therein. In various aspects, the present disclosure pertains to compositions including a cross-linked quantum dot nanoparticle matrix including a plurality of nanoparticle quantum dots cross- linked by ligands. With further reference to the description below, the ligands include: compounds of the formula

Yi- i-OH .

one or more compounds including an isocyanate group or an isothiocyanate group; one or more compounds including at least two alcohol groups, at least two thiol groups or a combination thereof; or a combination thereof.

[0010] Before the present compounds, compositions, articles, systems, devices, and/or methods are disclosed and described, it is to be understood that they are not limited to specific synthetic methods unless otherwise specified, or to particular reagents unless otherwise specified, as such can, of course, vary. It is also to be understood that the terminology used herein is for the purpose of describing particular aspects only and is not intended to be limiting.

[0011] Various combinations of elements of this disclosure are encompassed by this disclosure, e.g., combinations of elements from dependent claims that depend upon the same independent claim.

[0012] Moreover, it is to be understood that unless otherwise expressly stated, it is in no way intended that any method set forth herein be construed as requiring that its steps be performed in a specific order. Accordingly, where a method claim does not actually recite an order to be followed by its steps or it is not otherwise specifically stated in the claims or descriptions that the steps are to be limited to a specific order, it is in no way intended that an order be inferred, in any respect. This holds for any possible non-express basis for interpretation, including: matters of logic with respect to arrangement of steps or operational flow; plain meaning derived from grammatical organization or punctuation; and the number or type of aspects described in the specification.

[0013] All publications mentioned herein are incorporated herein by reference to disclose and describe the methods and/or materials in connection with which the publications are cited.

Definitions

[0014] It is also to be understood that the terminology used herein is for the purpose of describing particular aspects only and is not intended to be limiting. As used in the specification and in the claims, the term "comprising" can include the embodiments "consisting of and "consisting essentially of." Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this disclosure belongs. In this specification and in the claims which follow, reference will be made to a number of terms which shall be defined herein.

[0015] As used in the specification and the appended claims, the singular forms "a,"

"an" and "the" include plural referents unless the context clearly dictates otherwise. Thus, for example, reference to a mixture including "a quantum dot" includes mixtures of two or more quantum dots.

[0016] As used herein, the term "combination" is inclusive of blends, mixtures, alloys, reaction products, and the like. [0017] Ranges can be expressed herein as from one value (first value) to another value (second value). When such a range is expressed, the range includes in some aspects one or both of the first value and the second value. Similarly, when values are expressed as approximations, by use of the antecedent 'about,' it will be understood that the particular value forms another aspect. It will be further understood that the endpoints of each of the ranges are significant both in relation to the other endpoint, and independently of the other endpoint. It is also understood that there are a number of values disclosed herein, and that each value is also herein disclosed as "about" that particular value in addition to the value itself. For example, if the value "10" is disclosed, then "about 10" is also disclosed. It is also understood that each unit between two particular units are also disclosed. For example, if 10 and 15 are disclosed, then 11, 12, 13, and 14 are also disclosed.

[0018] As used herein, the terms "about" and "at or about" mean that the amount or value in question can be the designated value, approximately the designated value, or about the same as the designated value. It is generally understood, as used herein, that it is the nominal value indicated ±10% variation unless otherwise indicated or inferred. The term is intended to convey that similar values promote equivalent results or effects recited in the claims. That is, it is understood that amounts, sizes, formulations, parameters, and other quantities and characteristics are not and need not be exact, but can be approximate and/or larger or smaller, as desired, reflecting tolerances, conversion factors, rounding off, measurement error and the like, and other factors known to those of skill in the art. In general, an amount, size, formulation, parameter or other quantity or characteristic is "about" or "approximate" whether or not expressly stated to be such. It is understood that where "about" is used before a quantitative value, the parameter also includes the specific quantitative value itself, unless specifically stated otherwise.

[0019] As used herein, the terms "optional" or "optionally" means that the subsequently described event or circumstance can or cannot occur, and that the description includes instances where said event or circumstance occurs and instances where it does not. For example, the phrase "optional additional additives" means that the additional additives can or cannot be included and that the description includes compositions that both include and do not include additional additives.

[0020] Disclosed are the components to be used to prepare the compositions of the disclosure as well as the compositions themselves to be used within the methods disclosed herein. These and other materials are disclosed herein, and it is understood that when combinations, subsets, interactions, groups, etc. of these materials are disclosed that while specific reference of each various individual and collective combinations and permutation of these compounds cannot be explicitly disclosed, each is specifically contemplated and described herein. For example, if a particular compound is disclosed and discussed and a number of modifications that can be made to a number of molecules including the compounds are discussed, specifically contemplated is each and every combination and permutation of the compound and the modifications that are possible unless specifically indicated to the contrary. Thus, if a class of molecules A, B, and C are disclosed as well as a class of molecules D, E, and F and an example of a combination molecule, A-D is disclosed, then even if each is not individually recited each is individually and collectively

contemplated meaning combinations, A-E, A-F, B-D, B-E, B-F, C-D, C-E, and C-F are considered disclosed. Likewise, any subset or combination of these is also disclosed. Thus, for example, the sub-group of A-E, B-F, and C-E would be considered disclosed. This concept applies to all aspects of this application including, but not limited to, steps in methods of making and using the compositions of the disclosure. Thus, if there are a variety of additional steps that can be performed it is understood that each of these additional steps can be performed with any specific aspect or combination of aspects of the methods of the disclosure.

[0021] References in the specification and concluding claims to parts by weight of a particular element or component in a composition or article, denotes the weight relationship between the element or component and any other elements or components in the composition or article for which a part by weight is expressed. Thus, in a compound containing 2 parts by weight of component X and 5 parts by weight component Y, X and Y are present at a weight ratio of 2:5, and are present in such ratio regardless of whether additional components are contained in the compound.

[0022] A weight percent of a component, unless specifically stated to the contrary, is based on the total weight of the formulation or composition in which the component is included.

[0023] As used herein the terms "weight percent," "wt%," and "wt. %," which can be used interchangeably, indicate the percent by weight of a given component based on the total weight of the composition, unless otherwise specified. That is, unless otherwise specified, all wt% values are based on the total weight of the composition. It should be understood that the sum of wt% values for all components in a disclosed composition or formulation are equal to 100. [0024] Unless otherwise stated to the contrary herein, all test standards are the most recent standard in effect at the time of filing this application.

[0025] Each of the materials disclosed herein are either commercially available and/or the methods for the production thereof are known to those of skill in the art.

[0026] It is understood that the compositions disclosed herein have certain functions.

Disclosed herein are certain structural requirements for performing the disclosed functions and it is understood that there are a variety of structures that can perform the same function that are related to the disclosed structures, and that these structures will typically achieve the same result.

Compositions including cross-linked quantum dot nanoparticle matrix

[0027] Aspects of the disclosure relate to a composition including a cross-linked quantum dot nanoparticle matrix. The cross-linked quantum dot nanoparticle matrix includes a plurality of nanoparticle quantum dots cross-linked by ligands. In some aspects the ligands include:

compounds of Formula (1)

one or more compounds including an isocyanate group or an isothiocyanate according to Formulas (2) to (5)

(2)

(4)

one or more compounds including at least two alcohol groups, at least two thiol or a combinati or (7)

(6)

or a combination thereof, wherein

Rl is a Ci-24 alkyl, a C3-24 cycloalkyl, a C3-24 cycloalkyl-alkyl, a C4-24 aryl, a C4-24 alkyl-aryl, a C4-24 heteroaromatic, or a C4-24 alkyl-heteroaromatic,

Zl, Z2, Z3, Z4, Z5 and Z6 are independently an isocyanate or isothiocyanate,

R2 is a Ci-24 alkyl, a C3-24 cycloalkyl, a C3-24 cycloalkyl-alkyl, a C6-24 aryl, a C6-24 alkyl-aryl, a C4-24 heteroaromatic, or a C4-24 alkyl-heteroaromatic,

R3, R4 and R5 are independently a Ci-24 alkyl, a C3-24 cycloalkyl, a C3-24 cycloalkyl- alkyl, a C6-24 alkyl-aryl, a C4-24 heteroaromatic, or a C4-24 alkyl-heteroaromatic,

VI, V2 and V3 are independently O or S,

XI, X2 and X3 are independently N, P or hydrocarbon,

n is 1 or 2,

R6 is independently H or a methyl group,

m is an integer from 1 to 200,

R7 and R8 are independently a Ci-24 alkyl, a C3-24 cycloalkyl, a C3-24 cycloalkyl-alkyl, a C6-24 aryl, a C6-24 alkyl-aryl, a C4-24 heteroaromatic, or a C4-24 alkyl-heteroaromatic,

o is an integer from 1 to 1000,

Z7 is independently an alcohol group or a thiol group, and

R9 is a Ci-24 alkyl, a C3-24 cycloalkyl, a C3-24 cycloalkyl-alkyl, a C6-24 aryl, a C6-24 alkyl-aryl, a C4-24 heteroaromatic, or a C4-24 alkyl-heteroaromatic. [0028] In some aspects the plurality of quantum dots in the composition have an absorption wavelength of from about 300 nanometers (nm) to about 480 nm. In certain aspects the plurality of quantum dots can emit green and/or red light when they absorb blue light.

[0029] The composition according to particular aspects of the disclosure may include: from about 0.1 wt% to about 20 wt% nanoparticle quantum dots; from about 10 wt% to about 80 wt% one or more compounds including an isocyanate group or an isothiocyanate group according to Formulas (2) to (5); and from about 10 wt% to about 80 wt% one or more compounds including at least two alcohol groups, at least two thiol groups or a combination thereof, according to Formulas (6) or (7).

[0030] FIG. 1 illustrates a portion of a quantum dot nanoparticle matrix 100 according to an aspect of the disclosure. The quantum dot nanoparticle matrix 100 includes a plurality of nanoparticle quantum dots 200 and a plurality of ligands 300 that cross-link the plurality of nanoparticle quantum dots 200. The nanoparticle quantum dots 200 are separated from one another by a distance (e.g., dl, d2). In some aspects the plurality of nanoparticle quantum dots 200 in the nanoparticle matrix 100 are spaced apart from each other by at least about 10 nanometers (nm). The spacing is ensured by selection of ligands 300 according to the formulas described herein. Having the plurality of nanoparticle quantum dots 200 spaced apart by at least 10 nm minimizes Forster Resonance Energy Transfer (FRET), also referred to as fluorescence resonance energy transfer, in which non-radiative energy is transferred from a fluorescent donor (e.g., a quantum dot emitting light at a higher energy) to a lower energy acceptor (e.g., a quantum dot emitting light at a lower energy) through long-range dipole-dipole interactions.

[0031] In some aspects one or more of the plurality of nanoparticle quantum dots is a metal nanomaterial or an inorganic nanomaterial. The form of the plurality of nanoparticle quantum dots may include in certain aspects a nanoparticle, a nanofiber, a nanorod, or a nanowire.

[0032] The plurality of nanoparticle quantum dots may have a size of from about 1 nanometer (nm) to about 100 nm in some aspects. In particular aspects the plurality of nanoparticle quantum dots have a size of from about 1 nm to about 50 nm, or from about 1 nm to about 30 nm.

[0033] Exemplary quantum dots according to aspects of the disclosure may include, but are not limited to, semiconductor nanocrystals selected from the group consisting of, but not limited to, Group II- VI semiconductor compounds, Group II-V semiconductor compounds, Group III-VI semiconductor compounds, Group III-V semiconductor compounds, Group IV-VI semiconductor compounds, Group II-III-VI compounds, Group II- IV-VI compounds, Group II-IV-V compounds, alloys thereof and combinations thereof.

[0034] Exemplary Group II elements include Zn, Cd, Hg or a combination thereof.

[0035] Exemplary Group III elements include Al, Ga, In, Ti or a combination thereof.

[0036] Exemplary Group IV elements include Si, Ge, Sn, Pb or a combination thereof.

[0037] Exemplary Group V elements include P, As, Sb, Bi or a combination thereof.

[0038] Exemplary Group VI elements include O, S, Se, Te or a combination thereof.

[0039] Exemplary Group II-VI semiconductor compounds include binary compounds, e.g., CdSe, CdTe, ZnS, ZnSe, ZnTe, ZnO, HgS, HgSe and HgTe; ternary compounds, e.g., CdSeS, CdSeTe, CdSTe, ZnSeS, ZnSeTe, ZnSTe, HgSeS, HgSeTe, HgSTe, CdZnS, CdZnSe, CdZnTe, CdHgS, CdHgSe, CdHgTe, HgZnS and HgZnSe; and quaternary compounds, e.g., CdZnSeS, CdZnSeTe, CdZnSTe, CdHgSeS, CdHgSeTe, CdHgSTe, HgZnSeS, HgZnSeTe and HgZnSTe.

[0040] Exemplary Group III-V semiconductor compounds include binary compounds, e.g., GaN, GaP, GaAs, GaSb, A1N, A1P, AlAs, AlSb, InN, InP, InAs and InSb; ternary compounds, e.g., GaNP, GaNAs, GaNSb, GaPAs, GaPSb, A1NP, AINAs, AINSb, AlPAs, AlPSb, InNP, InNAs, InN Sb, InPAs, InPSb, GaAlNP, AlGaN, AlGaP, AlGaAs, AlGaSb, InGaN, InGaP, InGaAs, InGaSb, AlInN, AllnP, AlInAs and AllnSb; and quaternary compounds, e.g., GaAlNAs, GaAlNSb, GaAlPAs, GaAlPSb, GalnNP, Gain, NAs, GalnNSb, GalnPAs, GalnPSb, InAlNP, InAlNAs, InAlNSb, InAlPAs and InAlPSb.

[0041] Exemplary Group IV-VI semiconductor compounds include binary compounds, e.g., SnS, SnSe, SnTe, PbS, PbSe and PbTe; ternary compounds, e.g., SnSeS, SnSeTe, SnSTe, PbSeS, PbSeTe, PbSTe, SnPbS, SnPbSe and SnPbTe; and quaternary compounds, e.g., SnPbSSe, SnPbSeTe and SnPbSTe.

[0042] Exemplary Group IV semiconductor compounds include unary compounds, e.g., Si and Ge; and binary compounds, e.g., SiC and SiGe.

[0043] In yet further aspects each of the plurality of nanoparticle quantum dots include a concentration-gradient quantum dot. A concentration-gradient quantum dot includes an alloy of at least two semiconductors. The concentration (molar ratio) of the first semiconductor gradually increases from the core of the quantum dot to the outer surface of the quantum dot, and the concentration (molar ratio) of the second semiconductor gradually decreases from the core of the quantum dot to the outer surface of the quantum dot. Exemplary concentration-gradient quantum dots are described in, e.g., U.S. Patent No.

7,981,667, the disclosure of which is incorporated herein by this reference in its entirety.

[0044] In one aspect, the concentration-gradient quantum dot includes two semiconductors, a first semiconductor having the formula

CdxZm-xSySei-y

and a maximum molar ratio at the core of the stabilized quantum dot that gradually decreases to a minimum molar ratio at the outer surface of the quantum dot and a second semiconductor having the formula

ZnzSei-zSwSe l-w

and a maximum molar ratio at the outer surface of the stabilized quantum dot that gradually decreases to a minimum molar ratio at the core of the stabilized quantum dot.

[0045] In another aspect, the concentration-gradient quantum dot includes two semiconductors, a first semiconductor having the formula

CdZn_xSi-x

ZnCdzSi-z

[0046] Where the plurality of nanoparticle quantum dots are described herein as having a shell or a multi-shell structure (i.e., a core and at least one shell), the core and the shell or plurality of shells may independently be formed of the semiconductor materials described above.

[0047] The quantum dot nanoparticle matrix 100 may further include in some aspects any suitable polymer. Suitable polymers include, but are not limited to, polycarbonate (PC), polyethylene terephthalate (PET), polymethyl methacrylate (PMMA), polyaryletherketones (PAEK), polyimides, polyolefins, polystyrene, or a combination thereof.

[0048] In some aspects the quantum dot nanoparticle matrix 100 is in the form of a film. The quantum dot nanoparticle matrix 100 may include one or more additional films or layers, such as a barrier film, in certain aspects. A barrier film may provide further protection to the quantum dot nanoparticle matrix 100. Conventional barrier films include an inorganic layer. Exemplary materials for use in a barrier film include, but are not limited to, metal oxides, metal nitrides, metal carbides, metal oxynitrides, metal oxyborides, and combinations thereof, e.g., silicon oxides such as silica, aluminum oxides such as alumina, titanium oxides such as titania, indium oxides, tin oxides, indium tin oxide ("ITO"), tantalum oxide, zirconium oxide, niobium oxide, boron carbide, tungsten carbide, silicon carbide, aluminum nitride, silicon nitride, boron nitride, aluminum oxynitride, silicon oxynitride, boron oxynitride, zirconium oxyboride, titanium oxyboride, and combinations thereof.

[0049] The quantum dot nanoparticle matrix 100 and/or one or more additional films or layers (if included) may in some aspects include optional additional additives, as desired, that do not adversely affect the optical properties of the plurality of quantum dots 200 in the quantum dot nanoparticle matrix 100. Exemplary optional additional additives include, but are not limited to, a scattering material, a coupling agent, a leveling agent, a dispersant, a binder, a scavenger, a stabilizer and a combination thereof.

[0050] In some aspects the quantum dot nanoparticle matrix 100 and/or one or more additional films or layers (if included) includes a scattering material. Scattering materials, which may include but are not limited to metal oxide particles, may be included to modify the optical properties of the plurality of quantum dots 200 by scattering light generated therefrom. Exemplary scattering materials include, but are not limited to, titanium dioxide (TiC ), silicon dioxide (SiC ), aluminum oxide (AI2O3), zinc oxide (ZnO), zinc peroxide (ZnC ), zirconium dioxide (ZrC ), and combinations thereof. The scattering material in some aspects has a particle size of from about 0.1 micrometer (μπι) to about 10 μπι.

[0051] In particular aspects the quantum dot nanoparticle matrix includes a plurality of nanoparticle quantum dots cross-linked by ligands, and the ligands include one or more compounds including an isocyanate group or an isothiocyanate group having a molecular weight of 800 or greater.

Methods for making a cross-linked quantum dot nanoparticle matrix

[0052] Aspects of the disclosure further relate to methods for making a composition including a cross-linked quantum dot nanoparticle matrix, including: combining a plurality of nanoparticle quantum dots and ligands; and heating the plurality of nanoparticle quantum dots and ligands to cure the composition and form the cross-linked quantum dot nanoparticle matrix. The ligands include:

compounds of Formula (1) one or more compounds including an isocyanate group or an isothiocyanate group according to Formulas (2) to (5) (2)

(4)

one or more compounds including at least two alcohol groups, at least two thiol or a combination thereof, according to Formulas (6) or (7)

or a combination thereof, wherein

Rl is a Ci-24 alkyl, a C3-24 cycloalkyl, a C3-24 cycloalkyl-alkyl, a C4-24 aryl, a C4-24 alkyl-aryl, a C4-24 heteroaromatic, or a C4-24 alkyl-heteroaromatic, Zl, Z2, Z3, Z4, Z5 and Z6 are independently an isocyanate or isothiocyanate,

VI, V2 and V3 are independently O or S,

XI, X2 and X3 are independently N, P or hydrocarbon,

n is 1 or 2,

R6 is independently H or a methyl group,

m is an integer from 1 to 200,

o is an integer from 1 to 1000,

Z7 is independently an alcohol group or a thiol group, and

R9 is a Ci-24 alkyl, a C3-24 cycloalkyl, a C3-24 cycloalkyl-alkyl, a C6-24 aryl, a C6-24 alkyl-aryl, a C4-24 heteroaromatic, or a C4-24 alkyl-heteroaromatic.

[0053] The heating step is performed at a temperature sufficient to cross-link the ligands in the quantum dot nanoparticle matrix. In some aspects the heating is performed at a temperature of from about 60 to about 120 degrees Celsius (°C).

Properties of Nanoparticle quantum dots

[0054] In some aspects, the plurality of nanoparticle quantum dots in the nanoparticle matrix are dispersed such that a film/article including the nanoparticle matrix exhibits no appreciable degradation of optical properties after chemical exposure with acetone for 5 minutes. In some aspects, "no appreciable degradation of optical properties" means that, when the composition including the quantum dot nanoparticle matrix is exposed to the stated condition, the emission spectra of the composition either does not change or does not change to a substantial degree (e.g., the change is less than about 10%). Emission spectra of a composition may be quantified by measuring the width of the Gaussian curve of the emission spectra at half of its maximum value, known as "full width at half maximum," or FWHM. Degradation of quantum dots in the composition under adverse conditions such as those described herein can cause their FWHM to increase and their peak wavelength to shift, resulting in a change in optical properties. Thus, in some aspects "no appreciable degradation of optical properties" refers to a change in FWHM of no more than about 10% or a shift in peak wavelength (PWL) of no more than about 10%. In further aspects, "no appreciable degradation of optical properties" means that, when the composition including the quantum dot nanoparticle matrix is exposed to the stated condition, it exhibits a shift in PWL of less than 20 nm, or less than 15 nm, or less than 10 nm, or less than 5 nm. In further aspects, "no appreciable degradation of optical properties" means that, when the composition including the quantum dot nanoparticle matrix is exposed to the stated condition, it exhibits a reduction in luminance of less than about 10% as compared to the luminance of the composition prior to exposure to the stated condition.

Articles of Manufacture

[0055] Aspects of the disclosure also relate to an article including the cross-linked quantum dot nanoparticle matrix described herein. In some aspects the article is film. In certain aspects the film has a thickness of from about 0.5 micron (μπι) to about 500 μπι. The film may be incorporated into a display for an electronic device. The electronic device may include but is not limited to a mobile device, a tablet device, a gaming system, a handheld electronic device, a wearable device, a television, a desktop computer, or a laptop computer. The quantum dot film may in particular aspects be used in multi-layer extrusion (MLE), micro lens, prism and diffuser applications.

[0056] Various combinations of elements of this disclosure are encompassed by this disclosure, e.g., combinations of elements from dependent claims that depend upon the same independent claim.

Aspects of the Disclosure

[0057] In various aspects, the present disclosure pertains to and includes at least the following aspects.

[0058] Aspect 1 : A composition comprising, consisting of or consisting essentially of a cross-linked quantum dot nanoparticle matrix, wherein the cross-linked quantum dot nanoparticle matrix comprises a plurality of nanoparticle quantum dots cross-linked by ligands, the ligands comprising:

compounds of Formula (1)

Yf— R-_j-OH

one or more compounds comprising an isocyanate group or an isothiocyanate group according to Formulas (2) to (5)

1 ^R2 ^z2

one or more compounds comprising at least two alcohol groups, at least two thiol groups or a combination thereof, according to Formulas (6) or (7)

7 ^f 9 ^7 (7);

or a combination thereof, wherein

Zl, Z2, Z3, Z4, Z5 and Z6 are independently an isocyanate or isothiocyanate, R2 is a Ci-24 alkyl, a C3-24 cycloalkyl, a C3-24 cycloalkyl-alkyl, a C6-24 aryl, a C6-24 alkyl-aryl, a C4-24 heteroaromatic, or a C4-24 alkyl-heteroaromatic, R3, R4 and R5 are independently a Ci-24 alkyl, a C3-24 cycloalkyl, a C3-24 cycloalkyl- alkyl, a C6-24 alkyl-aryl, a C4-24 heteroaromatic, or a C4-24 alkyl-heteroaromatic,

VI, V2 and V3 are independently O or S,

XI, X2 and X3 are independently N, P or hydrocarbon,

n is 1 or 2,

R6 is independently H or a methyl group,

m is an integer from 1 to 200,

o is an integer from 1 to 1000,

Z7 is independently an alcohol group or a thiol group, and

[0059] Aspect 2: The composition according to Aspect 1, wherein the plurality of quantum dots have an absorption wavelength of from about 300 nanometers (nm) to about 480 nm.

[0060] Aspect 3 : The composition according to Aspect 1 or 2, wherein the plurality of quantum dots have a size of from about 1 nm to about 30 nm.

[0061] Aspect 4: The composition according to any of Aspects 1 to 3, wherein the composition comprises:

from about 0.1 wt% to about 20 wt% nanoparticle quantum dots;

from about 10 wt% to about 80 wt% one or more compounds comprising an isocyanate group or an isothiocyanate group according to Formulas (2) to (5); and

from about 10 wt% to about 80 wt% one or more compounds comprising at least two alcohol groups, at least two thiol groups or a combination thereof, according to Formulas (6) or (7).

[0062] Aspect 5 : The composition according to any of Aspects 1 to 4, wherein the plurality of nanoparticle quantum dots in the nanoparticle matrix are spaced apart from each other by at least about 10 nanometers (nm).

[0063] Aspect 6: The composition according to any of Aspects 1 to 5, wherein the plurality of nanoparticle quantum dots in the nanoparticle matrix are dispersed such that the composition exhibits no appreciable degradation of optical properties after chemical exposure with acetone for 5 minutes. [0064] Aspect 7: The composition according to any of Aspects 1 to 6, wherein the plurality of nanoparticle quantum dots in the nanoparticle matrix comprise a metal nanomaterial or an inorganic nanomaterial.

[0065] Aspect 8: The composition according to any of Aspects 1 to 7, wherein one or more of the plurality of nanoparticle quantum dots in the nanoparticle matrix is a nanofiber, a nanorod, or a nanowire.

[0066] Aspect 9: An article comprising the composition according to any of Aspects l to 8.

[0067] Aspect 10: The article according to Aspect 9, wherein the article is a film having a thickness of from about 0.5 micron (um) to about 500 μιη.

[0068] Aspect 11 : The article according to Aspect 9 or 10, wherein the article is a display for an electronic device.

[0069] Aspect 12: The article according to Aspect 11, wherein the electronic device is a mobile device, a tablet device, a gaming system, a handheld electronic device, a wearable device, a television, a desktop computer, or a laptop computer.

[0070] Aspect 13 : A method for making a composition comprising a cross-linked quantum dot nanoparticle matrix, comprising, consisting of or consisting essentially of:

(a) combining a plurality of nanoparticle quantum dots and ligands comprising: compounds of Formula (1)

Υ,- !-OH

1~~^R2~^Z2 (2)

(3)

Z₇-R₉-Z_{7 (7);}

or a combination thereof, wherein

Zl, Z2, Z3, Z4, Z5 and Z6 are independently an isocyanate or isothiocyanate,

VI, V2 and V3 are independently O or S,

XI, X2 and X3 are independently N, P or hydrocarbon,

n is 1 or 2,

R6 is independently H or a methyl group,

m is an integer from 1 to 200, R7 and R8 are independently a Ci-24 alkyl, a C3-24 cycloalkyl, a C3-24 cycloalkyl-alkyl, a C6-24 aryl, a C6-24 alkyl-aryl, a C4-24 heteroaromatic, or a C4-24 alkyl-heteroaromatic,

o is an integer from 1 to 1000,

Z7 is independently an alcohol group or a thiol group, and

R9 is a Ci-24 alkyl, a C3-24 cycloalkyl, a C3-24 cycloalkyl-alkyl, a C6-24 aryl, a C6-24 alkyl-aryl, a C4-24 heteroaromatic, or a C4-24 alkyl-heteroaromatic; and

(b) heating the plurality of nanoparticle quantum dots and ligands to cure the composition and form the cross-linked quantum dot nanoparticle matrix.

[0071] Aspect 14: The method according to Aspect 13, wherein the heating is performed at a temperature of from about 60 to about 120 degrees Celsius.

[0072] Aspect 15: The method according to Aspect 13 or 14, wherein the plurality of quantum dots have an absorption wavelength of from about 300 nanometers (nm) to about

480 nm.

[0073] Aspect 16: The method according to any of Aspects 13 to 15, wherein the plurality of quantum dots have a size of from about 1 nm to about 30 nm.

[0074] Aspect 17: The method according to any of Aspects 13 to 16, wherein the composition comprises:

from about 0.1 wt% to about 20 wt% nanoparticle quantum dots;

[0075] Aspect 18: The method according to any of Aspects 13 to 17, wherein the plurality of nanoparticle quantum dots in the nanoparticle matrix are spaced apart from each other by at least about 10 nanometers (nm).

[0076] Aspect 19: The method according to any of Aspects 13 to 18, wherein the plurality of nanoparticle quantum dots in the nanoparticle matrix are dispersed such that the composition exhibits no appreciable degradation of optical properties after chemical exposure with acetone for 5 minutes.

[0077] Aspect 20: An article formed from the method according to any of Aspects 13 to 19.

[0078] Aspect 21 : The article according to Aspect 20, wherein the article is a film having a thickness of from about 0.5 micron (μιη) to about 500 μιη. [0079] Aspect 22: The article according to Aspect 20 or 21, wherein the article is a display for an electronic device.

[0080] Aspect 23 : The article according to Aspect 22, wherein the electronic device is a mobile device, a tablet device, a gaming system, a handheld electronic device, a wearable device, a television, a desktop computer, or a laptop computer.

EXAMPLES

[0081] The following examples are put forth so as to provide those of ordinary skill in the art with a complete disclosure and description of how the compounds, compositions, articles, devices and/or methods claimed herein are made and evaluated, and are intended to be purely exemplary and are not intended to limit the disclosure. Efforts have been made to ensure accuracy with respect to numbers (e.g., amounts, temperature, etc.), but some errors and deviations should be accounted for. Unless indicated otherwise, parts are parts by weight, temperature is in °C or is at ambient temperature, and pressure is at or near atmospheric. Unless indicated otherwise, percentages referring to composition are in terms ofwt%.

[0082] There are numerous variations and combinations of reaction conditions, e.g., component concentrations, desired solvents, solvent mixtures, temperatures, pressures and other reaction ranges and conditions that can be used to optimize the product purity and yield obtained from the described process. Only reasonable and routine experimentation will be required to optimize such process conditions.

[0083] The compositions in Table 1 were prepared, including compositions Exl and

Ex2 according to aspects of the disclosure and comparative compositions CI and C2. Exl and CI included red and green quantum dots with -OH groups (1 milliliter (ml) and 2 ml, respectively), and Ex2 and C2 included red and green quantum dots without -OH groups (1 ml and 2 ml, respectively). Inventive compositions Exl and Ex2 each included a plurality of ligands:

Ligand 1 (Duranate TKA-100, an isocyanurate trimer, available from Asahi Kasei) (2 gram (g)), with the formula

(¾Η ι:·?~ΝΟΟ

OCX— C ί,Η ^<:"^' * "γ^{' ; '"}·,·.;! ^~ CO

° ; and Ligand 2 (Duranol T5631, a polyalkylene carbonate diol, available from Asahi Kasei) (4 g), with the formula

The compositions of Exl and Ex2 were heated to cross-link the ligands with the quantum dots into the nanoparticle quantum dot matrix. C 1 and C2 substituted 6 grams poly(methyl methacrylate) (PMMA) (molecular weight 110,000, available from Aldrich) for the ligands. PMMA was selected as a representative polymer that does not cross-link.

Table 1. Composition of examples and controls

[0084] Optical performance of the compositions was measured before and after a chemical resistance test was applied to the compositions. The chemical resistance test was performed by coating a glass slide with the composition, dipping the coated slide into acetone for 5 minutes, and then drying the glass slide in an oven at 120 °C for 3 minutes. Results of the optical testing are shown in Table 2:

Table 2. Optical performance of cross-linked QD films and controls

after chemical resistance test

Luminance (cd/m²)

660 590 210 200 after chemical resistance test

[0085] As shown by the data, the color coordinates of Exl compared to CI and Ex2 compared to C2 are similar before the chemical resistance test. After the chemical resistance test, while the color coordinates of Ex 1 and Ex2 are somewhat comparable to their original values (within 95% of their original values), the color coordinates of the comparative compositions have shifted substantially and more closely resemble that of blue light (see the GaN blue LED light shown as a reference). Similarly, luminance (in candela per square meter, or cd/m²) of Exl and Ex2 is within 90% (i.e., less than 10% change) as compared to the luminance of the compositions prior to the chemical resistance test. In contrast, the luminance of CI and C2 drops precipitously (greater than 50%) after the chemical resistance test). The improved color and luminance of Exl and Ex2 following the chemical resistance test is due to the cross-linked quantum dot matrix, which protects the quantum dots from chemical degradation. In addition, the ligands prevent agglomeration of quantum dots in the matrix and minimize Dexter energy transfer (DET) and Forster resonance energy transfer (FRET) between aggregated quantum dots, improving the luminance of the compositions.

[0086] Method examples described herein can be machine or computer-implemented at least in part. Some examples can include a computer-readable medium or machine- readable medium encoded with instructions operable to configure an electronic device to perform methods as described in the above examples. An implementation of such methods can include code, such as microcode, assembly language code, a higher-level language code, or the like. Such code can include computer readable instructions for performing various methods. The code may form portions of computer program products. Further, in an example, the code can be tangibly stored on one or more volatile, non-transitory, or nonvolatile tangible computer-readable media, such as during execution or at other times.

Examples of these tangible computer-readable media can include, but are not limited to, hard disks, removable magnetic disks, removable optical disks (e.g., compact disks and digital video disks), magnetic cassettes, memory cards or sticks, random access memories (RAMs), read only memories (ROMs), and the like.

[0087] The above description is intended to be illustrative, and not restrictive. For example, the above-described examples (or one or more aspects thereof) may be used in combination with each other. Other aspects can be used, such as by one of ordinary skill in the art upon reviewing the above description. The Abstract is provided to comply with 37 C.F.R. § 1.72(b), to allow the reader to quickly ascertain the nature of the technical disclosure. It is submitted with the understanding that it will not be used to interpret or limit the scope or meaning of the claims. Also, in the above Detailed Description, various features may be grouped together to streamline the disclosure. This should not be interpreted as intending that an unclaimed disclosed feature is essential to any claim. Rather, inventive subject matter may lie in less than all features of a particular disclosed aspect. Thus, the following claims are hereby incorporated into the Detailed Description as examples or aspects, with each claim standing on its own as a separate aspect, and it is contemplated that such aspects can be combined with each other in various combinations or permutations. The scope of the invention should be determined with reference to the appended claims, along with the full scope of equivalents to which such claims are entitled.

Claims

CLAIMS What is claimed is:

1. A composition comprising a cross-linked quantum dot nanoparticle matrix, wherein the cross-linked quantum dot nanoparticle matrix comprises a plurality of nanoparticle quantum dots cross-linked by ligands, the ligands comprising:

compounds of Formula (1) one or more compounds comprising an isocyanate group or an isothiocyanate group according to Formulas (2) to (5)

Z₇H ₉-Z₇ (7);

or a combination thereof, wherein

Zl, Z2, Z3, Z4, Z5 and Z6 are independently an isocyanate or isothiocyanate,

VI, V2 and V3 are independently O or S,

XI, X2 and X3 are independently N, P or hydrocarbon,

n is 1 or 2,

R6 is independently H or a methyl group,

m is an integer from 1 to 200,

o is an integer from 1 to 1000,

Z7 is independently an alcohol group or a thiol group, and

2. The composition according to claim 1, wherein the plurality of quantum dots have an absorption wavelength of from about 300 nanometers (nm) to about 480 nm.

3. The composition according to claim 1 or 2, wherein the plurality of quantum dots have a size of from about 1 nm to about 30 nm.

4. The composition according to any of claims 1 to 3, wherein the composition comprises:

from about 0.1 wt% to about 20 wt% nanoparticle quantum dots;

5. The composition according to any of claims 1 to 4, wherein the plurality of nanoparticle quantum dots in the nanoparticle matrix are spaced apart from each other by at least about 10 nanometers (nm).

6. The composition according to any of claims 1 to 5, wherein the plurality of nanoparticle quantum dots in the nanoparticle matrix are dispersed such that the composition exhibits no appreciable degradation of optical properties after chemical exposure with acetone for 5 minutes.

7. The composition according to any of claims 1 to 6, wherein the plurality of nanoparticle quantum dots in the nanoparticle matrix comprise a metal nanomaterial or an inorganic nanomaterial.

8. The composition according to any of claims 1 to 7, wherein one or more of the plurality of nanoparticle quantum dots in the nanoparticle matrix is a nanofiber, a nanorod, or a nanowire.

9. An article comprising the composition according to any of claims 1 to 8.

10. The article according to claim 9, wherein the article is a film having a thickness of from about 0.5 micron (μπι) to about 500 μπι.

11. The article according to claim 9 or 10, wherein the article is a display for an electronic device.

12. The article according to claim 11, wherein the electronic device is a mobile device, a tablet device, a gaming system, a handheld electronic device, a wearable device, a television, a desktop computer, or a laptop computer.

13. A method for making a composition comprising a cross-linked quantum dot nanoparticle matrix, comprising:

Yi-Ri-OH (i);

one or more compounds comprising an isocyanate group or an isothiocyanate according to Formulas (2) to (5)

Z f> ^jf

1 ¾ (2)

(5); one or more compounds comprising at least two alcohol groups, at least two thiol groups or a combination thereof, according to Formulas (6) or (7)

Z7-R9-Z7 (7);

or a combination thereof, wherein

Zl, Z2, Z3, Z4, Z5 and Z6 are independently an isocyanate or isothiocyanate,

VI, V2 and V3 are independently O or S,

XI, X2 and X3 are independently N, P or hydrocarbon,

n is 1 or 2,

R6 is independently H or a methyl group,

m is an integer from 1 to 200,

o is an integer from 1 to 1000,

Z7 is independently an alcohol group or a thiol group, and

14. The method according to claim 13, wherein the heating is performed at a temperature of from about 60 to about 120 degrees Celsius.

15. The method according to claim 13 or 14, wherein the plurality of quantum dots have an absorption wavelength of from about 300 nanometers (nm) to about 480 nm.

16. The method according to any of claims 13 to 15, wherein the plurality of quantum dots have a size of from about 1 nm to about 30 nm.

17. The method according to any of claims 13 to 16, wherein the composition comprises: from about 0.1 wt% to about 20 wt% nanoparticle quantum dots;

18. The method according to any of claims 13 to 17, wherein the plurality of nanoparticle quantum dots in the nanoparticle matrix are spaced apart from each other by at least about 10 nanometers (nm).

19. The method according to any of claims 13 to 18, wherein the plurality of nanoparticle quantum dots in the nanoparticle matrix are dispersed such that the composition exhibits no appreciable degradation of optical properties after chemical exposure with acetone for 5 minutes.

20. An article formed from the method according to any of claims 13 to 19.