WO2018104891A1 - Quantum dot film and applications thereof - Google Patents

Abstract

A light emitting film includes a first layer and a second layer and a quantum dot layer disposed between the first layer and the second layer. The quantum dot layer is formed from a quantum dot solution comprising a mixture of hyperbranched polymer, resin and quantum dots.

Description

QUANTUM DOT FILM AND APPLICATIONS THEREOF

Technical Field

[0001] The disclosure generally relates to light emitting device and methods and more particularly to methods and structures utilizing a quantum dot film. More particularly, the disclosure relates to methods and structures utilizing a quantum dot film where quantum dots are located on a hyperbranched polymer.

Background

[ΘΘ02] Direct conversion of electricity into light using semiconductor-based light-emitting diodes (LEDs) is widely accepted one of the most promising approaches to more efficient lighting. LEDs demonstrate high brightness, long operational lifetime, and lo energy consumption performance that far surpass that of conventional lighting systems such as incandescent and fluorescent light sources. The LED field is currently dominated by semiconductor quantum-well emitters (based, e.g., on InGaN/GaN) fabricated by epitaxial methods on crystalline substrates (e.g., sapphire). These structures are highly efficient, reliable, mature and bright, but structural defects at the substrate and semiconductor interface caused by lattice mismatch and heating during operation generally limits such devices to point light source with limited flexible compatibility.

[0003] OLEDs are easily amendable to low-temperature, large-area processing, including fabrication on flexible substrates. Synthetic organic chemistry provides essentially an unlimited number of degrees of freedom for tailoring molecular properties to achieve specific functionality, from selective charge transport to color-tunable light emission. The prospect of high-quality lighting sources based on inexpensive "plastic" materials has driven a tremendous amount of research in the area of OLEDs, which in turn has led to the realization of several OLED-based high-tech products such as flat screen televisions and mobile communication devices. Several industrial giants such as Samsung, LG, Sony, and Panasonic are working to develop large-area white-emitting OLEDs both for lighting and display. Despite advances in the OLED field, there are a few drawbacks of this technology that might prevent its widespread use in commercial products. One problem is poor cost-efficiency caused at least in part by the complexity of the necessary device architecture, which requires multiple thermal deposition steps during manufacture. Another problem is their limited stability, particularly for deep-red and blue phosphorescent OLEDs. While improving greatly in recent years, they still do not meet the standards employed in high-end devices. [0004] Chemically synthesized nanocrystal quantum dots (QDs) have emerged as a promising class of emissive materials for low-cost yet efficient LEDs. These luminescent nanomaterials feature size-controlled tunable emission wavelengths and provide

improvements in color purity, stability and durability over organic molecules. In addition, as with organic materials, colloidal QDs can be fabricated and processed via inexpensive solution-based techniques compatible with lightweight, flexible substrates. Moreover, similar to other semiconductor materials, colloidal QDs feature almost continuous above-band-edge absorption and a narrow emission spectrum at near-band-edge energies. Distinct from bulk semiconductors, however, the optical spectra of QDs depend directly on their size.

Specifically, their emission color can be continuously tuned from the infrared (IR) to ultraviolet (UV) by varying QD size and/or composition. The wide range spectral tunability is combined with high photolummescence (PL) quantum yields (QYs) that approach unity in weil-passivated structures. These unique properties of QDs have been explored for use in various devices such as LEDs, lasers, solar cells, and photo detectors.

[0005] It is known that the quantum dots can degrade when they are exposed in air and moisture. In presence of light, oxygen and moisture molecules may cause photo-oxidation and photo-corrosion on the surface of the quantum dots. Once quantum dots react with oxygen and moisture, new defects may be created on the surface of quantum dots. Such defects may result in decreased light emitting of quantum dots.

[0006] In conventional quantum dot films, a quantum dot may be disposed between a first barrier film and a second barrier film, as illustrated in FIG. 1. Suitable barrier films include polymers (e.g., PET); oxides such as silicon oxides, metal oxides, metal nitrides, metal carbides, metal oxynitrides, and combinations thereof. The barrier films are typically formed using techniques employed in the film metallizing art such as sputtering, evaporation, chemical vapor deposition, plasma deposition, atomic layer deposition, plating and the like. Second barrier film is typically laminated on a quantum dot layer and often includes an adhesion surface or layer. The thickness of each of the conventional barrier film layers is configured to eliminate wrinkling in a roll-to-roll or laminate manufacturing processes, as may be required by conventional methods described above.

[0007] These and other shortcomings are addressed by examples of the present disclosure. Summary

[0008] According to one example, a light emitting film comprising a first layer and a second layer; a quantum dot layer disposed between the first layer and the second layer; and wherein the quantum dot layer is formed from a quantum dot solution comprising a mixture of hyperbranched polymer, resin and quantum dots.

[0009] According to another example, a film for light emitting devices, the film formed from a process comprising providing a first layer; mixing a hyperbranched polymer with quantum dots and a resin to form a quantum dot solution; disposing a quantum dot solution on the first layer to form a quantum dot layer; and disposing a second layer on the quantum dot layer.

[0010] According to yet another example, a method comprising providing a first layer; mixing a hyperbranched polymer with quantum dots and a resin to form a quantum dot solution; disposing a quantum dot solution on the first layer to form a quantum dot layer; and disposing a second layer on the quantum dot layer.

Brief Description of the Drawings

[0011] The above-mentioned and other features and advantages of this disclosure, and the manner of attaining them, will become apparent and be better understood by reference to the following description of one example of the disclosure in conjunction with the accompanying drawings, wherein:

[0012] FIG. 1 is a chart schematically depicting transfer efficiency according to the distance between quantum dots.

[0013] FIG. 2 is a schematic representation of a composite layered structure according to examples of the present disclosure.

[0014] FIG. 3 is a schematic representation of a composite layered structure according to examples of the present disclosure.

[0015] FIG. 4 is a schematic representation of a quantum dot solution according to examples of the present disclosure.

[0016] FIG. 5 is a method flow diagram according to examples of the present disclosure. Detailed Description

[0017] The disclosure relates to quantum dot films and methods of forming quantum dot films with improved dispersion of the quantum dots. With reference to FIG. 1, the dispersion of quantum dots within a quantum dot layer factors into the quantum efficiency. In particular, FIG. 1 depicts transfer efficiency of a donor and an acceptor quantum dot as a function of interfluorophore distance in nanometers. As shown, transfer efficiency decreases with increasing distance at a non-linear rate. Adjacent donor and acceptor dots exhibit an efficiency of about .9. A distance of approximately 6 nanometers exhibits a transfer efficiency of about .6. A distance of about 7 nanometers exhibits a transfer efficiency of about .2. While close proximity of quantum dots produces high transfer efficiency, this proximity may decrease color accuracy. When the distance between quantum dots is too small, the close proximity of the dots results in a red shift of the emission peak within the film. This red shift affects the color accuracy of the film. Similarly, when large and small quantum dots are present, Forster Resonance Energy Transfer (FRET) phenomenon occurs. In particular, energy transfer from smaller quantum dots to larger quantum dots occurs when the large and small quantum dots are in close proximity. The FRET phenomenon decreases quantum efficiency and eventually leads to red shift, i.e. reduced color accuracy. As a result, retaining good dispersion of quantum dots within a quantum dot film is useful in maintaining color accuracy and quantum efficiency. As deduced from FIG. 1, good dispersion is a tradeoff between high transfer efficiency and reducing the likelihood of red shift. Good dispersion reduces the likelihood of red shift while maintaining reasonable transfer efficiency. As depicted in FIG. 1, distances greater than 2 nanometers will reduce the likelihood of red shift with acceptable levels of transfer efficiency exhibited between 2 nanometers and 8 nanometers. For example, 50% transfer efficiency is expected at about 5.5 nanometers. According to examples of the disclosure described below, a selected distance may be maintained through a hyperbranched polymer solution that locates the quantum dots. In the examples, a distance within the ranges described above may be maintained to produce suitable results in terms of transfer efficiency and red shift. As depicted in Fig. 1, distances of at least about 10 nanometers are employed to provide FRET efficiency near zero and minimize red shift.

[0018] FIG. 2 is a schematic side elevation view of an illustrative quantum dot (QD) film 200. In one or more examples, the QD film 200 includes a first layer 202, a second layer 204, and a quantum dot layer 206 disposed between the first layer 202 and the second layer 204.

[0019] The quantum dot layer 206 may include a quantum dot solution 210 dispersed in a polymer material 212 such as acryl type, epoxy type, or silicone type polymers, or combinations thereof. The quantum dot layer 206 may include one or more populations of quantum dot material 214. Exemplary quantum dots or quantum dot materials 214 emit green light and red light upon down-conversion of blue primary light from the blue LED to secondary light emitted by the quantum dots. The respective portions of red, green, and blue light can be controlled to achieve a desired white point for the white light emitted by a display device incorporating the quantum dot film article. Suitable quantum dot materials 214 for use in quantum dot film articles described herein include core/shell luminescent nanocrystals including CdSe/ZnS, InP/ZnS, PbSe/PbS, CdSe/CdS, CdTe/CdS or CdTe/ZnS. The quantum dot layer 206 can have any useful amount of quantum dot materials 214. In many examples the quantum dot layer 206 can have from about 0.05 wt% to about 5 wt% quantum dots. It is understood that various intervening endpoints in the proposed size ranges may be used. However, other loadings of quantum dot materials 214 may be used.

[0020] The quantum dot layer 206 may include scattering beads or particles. The inclusion of scattering particles results in a longer optical path length and improved quantum dot absorption and efficiency. The particle size is in a range from 50 nm to 10 micrometers, or from 100 nm to 6 micrometers. It is understood that various intervening endpoints in the proposed size ranges may be used. The quantum dot layer 206 may include fillers such as fumed silica.

[0021] The first layer 202 and second layer 204 may be formed of any useful material that can protect the quantum dots from environmental conditions such as oxygen and moisture. As discussed in more detail below, at least one of the first layer 202 and second layer 204 may be a barrier film 300. Suitable barrier films include polymers, glass or dielectric materials, for example. Suitable barrier film materials include, but are not limited to, polymers such as polyethylene terephthalate (PET); oxides such as silicon oxide, titanium oxide, or aluminum oxide (e.g., SiC , S12O3, T1O2, or AI2O3); and suitable combinations thereof.

[0022] With reference to FIG. 3, a barrier film 300 of the QD film 200 may include at least two layers of different materials or compositions, such that the multi-layered barrier eliminates or reduces pinhole defect alignment in the barrier layer, providing an effective barrier to oxygen and moisture penetration into the quantum dot layer 206. For example, barrier film 300 may include an inorganic layer 306 disposed on a base substrate 304 (e.g., polymer). Optionally, a diffuser layer 302 may be provided on base substrate 304 opposite inorganic layer 306. The inorganic layer 306 may include inorganic material such as a polysilazane-based polymer, a polysiloxane-based polymer. The inorganic layer may include oxides such as silicon oxide, titanium oxide, or aluminum oxide (e.g., S1O2, S12O3, T1O2, or AI2O3); and suitable combinations thereof. In certain examples, a coating 308 may be applied, for example, adjacent the inorganic layer 306. The coating 308 may be an adhesive coating (e.g., organic layer) and may improve the adhesion property with a QD layer, for example.

[0023] In addition, barrier polymer may include organic and inorganic hybrid materials. For example, the following structure may be used, where Rl is an organic component offering flexibility and R2 is an organic component that improves adhesion. o o

— o— Si— R1— Si — O—

O O

Si

R2

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[0024] Once the quantum dot solution is applied to first layer 202, quantum dot solution may be cured according to curing methods appropriate for the material including but not limited to ultraviolet (UV) curing. As an illustrative example, ultraviolet (UV) curing may be performed in a gastight aluminum casing equipped with low pressure mercury lamps (Hg LP; Heraeus Noblelight NIQ 65XL). The lamps may be configured to emit in the UV domain at about 254 nm (20 W) and in the VUV domain at about 185 nm (5 W) with a distance to the sample at 20 mm. A gas sweeping may be applied and may include a mixture of 99.9% pure dry nitrogen and 5% 02 in dry nitrogen. Before beginning the curing of the sample, atmosphere may be purged with nitrogen during 10 min (8 L/min) and lamps may be allowed to heat to nominal power. The curing may occur with a partial pressure of oxygen at the surface of the sample inferior or equal to 1%.

[0025] Once the quantum dot solution is cured to form quantum dot layer 206, second layer 204 may be applied. In addition to first and second layers, a curable protective layer coating composition can be applied externally of first and second layers and cured to provide a hardened film on the solid plastic form surface. The hardened film can provide an abrasion resistant coating layer. The hardened film can provide high surface hardness and a glass-like feel, and can provide a desirable combination of properties such as hardness, scratch resistance, mechanical strength, and impact resistance. A filler, polyester, or combination thereof, can produce a surprising increase in hardness as compared to the results of the treatment as performed on a solid plastic form free of filler and polyester.

[0026] The method can include coating a surface of a solid plastic form with a flowable curable coating composition. The coating can be performed in any suitable manner that forms a coating of the flowable curable coating composition on a surface of the solid plastic form. Wet or transfer coating methods can be used. For example, the coating can be bar coating, spin coating, spray coating, or dipping. Single- or multiple-side coating can be performed. [0027] The solid plastic form can be transparent, opaque, or any one or more colors. The solid plastic form can include any one or more suitable plastics (e.g., as a homogeneous mixture of plastics). In some examples, the solid plastic form can include at least one of an acrylonitrile butadiene styrene (ABS) polymer, an acrylic polymer, a celluloid polymer, a cellulose acetate polymer, a cycloolefin copolymer (COC), an ethylene-vinyl acetate (EVA) polymer, an ethylene vinyl alcohol (EVOH) polymer, a fluoroplastic, an ionomer, an acrylic/PVC alloy, a liquid crystal polymer (LCP), a polyacetal polymer (POM or acetal), a polyacrylate polymer, a polymethylmethacrylate polymer (PMMA), a polyacrylonitrile polymer (PAN or acrylonitrile), a polyamide polymer (PA or nylon), a polyamide-imide polymer (PAI), a polyaryletherketone polymer (PAEK), a polybutadiene polymer (PBD), a polybutylene polymer (PB), a polybutylene terephthalate polymer (PBT), a polycaprolactone polymer (PCL), a polychlorotrifluoroethylene polymer (PCTFE), a polytetrafluoroethylene polymer (PTFE), a polyethylene terephthalate polymer (PET), a polycyclohexylene dimethylene terephthalate polymer (PCT), a polycarbonate polymer (PC), a

polyhydroxyalkanoate polymer (PHA), a polyketone polymer (PK), a polyester polymer, a polyethylene polymer (PE), a polyetheretherketone polymer (PEEK), a

polyetherketoneketone polymer (PEKK), a polyetherketone polymer (PEK), a polyetherimide polymer (PEI), a polyethersulfone polymer (PES), a polyethylenechlorinate polymer (PEC), a polyimide polymer (PI), a polylactic acid polymer (PLA), a polymethylpentene polymer (PMP), a polyphenylene oxide polymer (PPO), a polyphenylene sulfide polymer (PPS), a polyphthalamide polymer (PPA), a polypropylene polymer, a polystyrene polymer (PS), a polysulfone polymer (PSU), a polytrimethylene terephthalate polymer (PTT), a polyurethane polymer (PU), a polyvinyl acetate polymer (PVA), a polyvinyl chloride polymer (PVC), a polyvinylidene chloride polymer (PVDC), a polyamideimide polymer (PAI), a polyarylate polymer, a polyoxymethylene polymer (POM), and a styrene-acrylonitrile polymer (SAN). In some examples, the solid plastic form includes at least one of polycarbonate polymer (PC) and polymethylmethacrylate polymer (PMMA). The solid plastic form can include a blend of PC and PMMA.

[0028] The solid plastic form can include one type of polycarbonate or multiple types of polycarbonate. The polycarbonate can be made via interfacial polymerization (e.g., reaction of bisphenol with phosgene at an interface between an organic solution such as methylene chloride and a caustic aqueous solution) or melt polymerization (e.g., transesterification and/or polycondensation of monomers or oligomers above the melt temperature of the reaction mass). Although the reaction conditions for interfacial polymerization may vary, in an example the procedure can include dissolving or dispersing a dihydric phenol reactant in aqueous caustic soda or potash, adding the resulting mixture to a suitable water-immiscible solvent medium, and contacting the reactants with a carbonate precursor (e.g., phosgene) in the presence of a catalyst such as triethylamine or a phase transfer catalyst, under controlled pH conditions, e.g., about 8 to about 10. The most commonly used water-immiscible solvents include methylene chloride, 1,2-dichIoroethane, chlorobenzene, toluene, and the like.

[0029] Alternatively, melt processes may be used to make the polycarbonates. Generally, in the melt polymerization process, polycarbonates may be prepared by co-reacting, in a molten state, the dihydroxy reactant(s) and a diaryl carbonate ester, such as diphenyi carbonate, in the presence of a transesterification catalyst in a mixer, twin screw extruder, or the like, to form a uniform dispersion. Volatile monohydric phenol can be removed from the molten reactants by distillation and the polymer can be isolated as a molten residue. In some examples, a melt process for making polycarbonates uses a diaryl carbonate ester having electron-withdrawing substituents on the and groups, such as bis(4-nitrophenyl)carbonate, bis(2-chlorophenyl)carbonate, bis(4-chlorophenyl)carbonate, bis(methyl salicyl)carbonate, bis(4-methylcarboxylphenyl)carbonate, bis(2-acetylphenyl)carboxylate, bis(4- acetylphenyl)carboxylate, or a combination thereof. In addition, transesterification catalysts for use may include phase transfer catalysts such as tetrabutylammonium hydroxide, methyltributylammonium hydroxide, tetrabutylammonium acetate, tetrabutylphosphonium hydroxide, tetrabutylphosphonium acetate, tetrabutylphosphonium phenolate, or a combination thereof

[0030] The one or more polycarbonates can be about 50 wt% to about 100 wt% of the solid plastic form, such as about 50 wt% or less, or about 55 wt%, 60, 65, 70, 75, 80, 85, 90, 95, 96, 97, 98, 99, 99.9 wt%, or about 99.99 wt% or more. In various examples, the polycarbon

[0031] Each phenyl ring in the structure is independently substituted or unsubstituted. The variable L³ is chosen from -S(0)2- and substituted or unsubstituted (Ci-C2o)hydrocarbylene. In various examples, the polycarbonate can be derived from bisphenol A, such that the polycarbon

[0032] The solid plastic form can include a filler, such as one filler or multiple fillers. The filler can be any suitable type of filler. The filler can be homogeneously distributed in the solid plastic form. The one or more fillers can form about 0.001 wt% to about 50 wt% of the solid plastic form, or about 0.01 wt% to about 30 wt%, or about 0.001 wt% or less, or about 0.01 wt%, 0.1, 1, 2, 3, 4, 5, 10, 15, 20, 25, 30, 35, 40, 45 wt%, or about 50 wt% or more. The filler can be fibrous or particulate. The filler can be aluminum silicate (mullite), synthetic calcium silicate, zirconium silicate, fused silica, crystalline silica graphite, natural silica sand, or the like; boron powders ; oxides such as TiC , aluminum oxide, magnesium oxide, or the like; calcium sulfate (as its anhydride, dehydrate or trihydrate); calcium carbonates such as chalk, limestone, marble, synthetic precipitated calcium carbonates, or the like; talc, including fibrous, modular, needle shaped, lamellar talc, or the like; wollastonite; surface- treated wollastonite; glass spheres such as hollow and solid glass spheres; kaolin; single crystal fibers or "whiskers" such as silicon carbide, alumina, boron carbide, iron, nickel, copper, or the like; fibers (including continuous and chopped fibers) such as asbestos, carbon fibers, glass fibers; sulfides such as molybdenum sulfide, zinc sulfide, or the like; barium compounds; metals and metal oxides such as particulate or fibrous materials; flaked fillers; fibrous fillers, for example short inorganic fibers such as those derived from blends including at least one of aluminum silicates, aluminum oxides, magnesium oxides, and calcium sulfate hemihydrate or the like; natural fillers and reinforcements; organic fillers such as

polytetrafluoroethylene, reinforcing organic fibrous fillers formed from organic polymers capable of forming fibers such as poly(ether ketone), polyimide, polybenzoxazole, poly(phenylene sulfide), polyesters, polyethylene, aromatic polyamides, aromatic polyimides, polyetherimides, polytetrafluoroethylene, acrylic resins, poly(vinyl alcohol) or the like; or combinations including at least one of the foregoing fillers. The filler can be selected from glass fibers, carbon fibers, a mineral fillers, or combinations thereof. The filler can be glass fibers. [0033] The glass fibers can be selected from E-glass, S-glass, AR-glass, T-glass, D-glass, R- glass, and combinations thereof. The glass fibers used can be selected from E-glass, S-glass, and combinations thereof. High-strength glass is generally known as S-type glass in the United States, R-glass in Europe, and T-glass in Japan. High-strength glass has appreciably higher amounts of silica oxide, aluminum oxide and magnesium oxide than E-glass. S-2 glass is approximately 40-70% stronger than E-glass. The glass fibers can be made by standard processes, e.g., by steam or air blowing, flame blowing, and mechanical pulling.

[0034] The glass fibers can be sized or unsized. Sized glass fibers are coated on their surfaces with a sizing composition selected for compatibility with the polycarbonate. The sizing composition facilitates wet-out and wet-through of the polycarbonate on the fiber strands and assists in attaining desired physical properties in the polycarbonate composition. The glass fibers can be sized with a coating agent. The coating agent can be present in an amount from about 0.1 wt% to about 5 wt%, or about 0.1 wt% to about 2 wt%, based on the weight of the glass fibers.

[0035] In preparing the glass fibers, a number of filaments can be formed simultaneously, sized with the coating agent and then bundled into what is called a strand. Alternatively the strand itself may be first formed of filaments and then sized. The amount of sizing employed is generally that amount which is sufficient to bind the glass filaments into a continuous strand and can be about 0.1 to about 5 wt%, about 0.1 to 2 wt%, or about 1 wt%, based on the weight of the glass fibers.

[0036] The glass fibers can be continuous or chopped. Glass fibers in the form of chopped strands may have a length of about 0.3 mm to about 10 cm, about 0.5 cm to about 5 cm, or about 1.0 mm to about 2.5 cm. In various further examples, the glass fibers can have a length of about 0.2 mm to about 20 mm, about 0.2 mm to about 10 mm, or about 0.7 mm to about 7 mm, 1 mm or longer, or 2 mm or longer. The glass fibers can have a round (or circular), flat, or irregular cross-section. The diameter of the glass fibers can be about 1 μπι to about 15 μπι, about 4 to about 10 μπι, about 1 μπι to about 10 μπι, or about 7 μπι to about 10 μπι.

[0037] The solid plastic form can include a polyester. The polyester can be any suitable polyester. The polyester can be chosen from aromatic polyesters, poly(alkylene esters) including poly(alkylene arylates) (e.g., poly(alkylene terephthalates)), and poly(cycloalkylene diesters) (e.g., poly(cycloghexanedimethylene terephthalate) (PCT), or poly(l,4-cyclohexane- dimethanol-l,4-cyclohexanedicarboxylate) (PCCD)), and resorcinol-based aryl polyesters. The polyester can be poly(isophthalate-terephthalate-resorcinol)esters, poly(isophthalate- terephthalate-bisphenol A)esters, poly[(isophthalate-terephthalate-resorcinol)ester-co- (isophthalate-terephthalate-bisphenol A)]ester, or a combination including at least one of these. Examples of poly(alkylene terephthalates) include poly(ethylene terephthalate) (PET), poly(l,4-butylene terephthalate) (PBT), and poly(propylene terephthalate) (PPT). Also useful are poly(alkylene naphthoates), such as poly(ethylene naphthanoate) (PEN), and poly(butylene naphthanoate) (PBN). Copolymers including alkylene terephthalate repeating ester units with other ester groups can also be useful. Useful ester units can include different alkylene terephthalate units, which can be present in the polymer chain as individual units, or as blocks of poly(alkylene terephthalates). Specific examples of such copolymers include poly(cyclohexanedimethylene terephthalate)-co-poly(ethylene terephthalate), abbreviated as PETG where the polymer includes greater than or equal to 50 mol % of poly(ethylene terephthalate), and abbreviated as PCTG where the polymer includes greater than 50 mol % of poly(l,4-cyclohexanedimethylene terephthalate). The polyester can be substantially homogeneously distributed in the solid plastic form. The solid plastic form can include one type of polyester or multiple types of polyester. The one or more polyesters can form any suitable proportion of the solid plastic form, such as about 0.001 wt% to about 50 wt% of the solid plastic form, about 0.01 wt% to about 30 wt%, or about 0.001 wt% or less, or about

0.01 wt%, 0.1, 1, 2, 3, 4, 5, 6, 8, 10, 12, 14, 16, 18, 20, 22, 24, 26, 28, 30, 35, 40, 45 wt%, or about 50 wt% or more. The polyester can includes a repeating unit having the structure:

O O

O R⁸ O

The variables R⁸ and R⁹ can be independently substituted or unsubstituted (Ci- C2o)hydrocarbylene. The variables R⁸ and R⁹ can be cycloalkylene-containing groups or aryl-containing groups. The variables R⁸ and R⁹ can be independently substituted or unsubstituted phenyl, or substituted or unsubstituted -(Co-Cio)hydrocarbyl-(C4- Cio)cycloalkyl-(Co-Cio)hydrocarbyl-. The variables R⁸ and R⁹ can both be cycloalkylene- containing groups. The variables R⁸ and R⁹ can independently have the structure:

wherein the cyclohexylene can be substituted in a cis or trans fashion. In some exampl can be a para-substituted phenyl, such that R⁹ appears in the polyester structure as:

[0038] The solid plastic form can have any suitable shape and size. In some examples, the solid plastic form is a sheet having any suitable thickness, such as a thickness of about 25 microns to about 50,000 microns, about 25 microns to about 15,000 microns, about 60 microns to about 800 microns, or about 25 microns or less, or about 50, 75, 100, 150, 200, 250, 300, 400, 500, 600, 700, 800, 900, 1,000, 1,500, 2,000, 3,000, 4,000, 5,000, 6,000, 8,000, 10,000, 12,000, 14,000, 15,000, 20,000, 25,000, 30,000, 40,000, or about 50,000 microns or more.

[0039] The flowable curable coating composition can include a) an alicyclic epoxy group- containing siloxane resin having a weight average molecular weight of about 1,000 to about 4,000 and a (M_w/M_n) of about 1.05 to about 1.4, b) an epoxy-functional organosiloxane and an organosiloxane comprising a isocyanate group or an isocyanurate group, or both a) and b).

[0040] The epoxy-functional organosiloxane can have the structure:

[0041] At each occurrence, R^a can be independently substituted or unsubstituted (Ci- Cio)alkyl. At each occurrence, the variable R^a can be independently unsubstituted (Ci- C6)alkyl. The variable L^a can be substituted or unsubstituted (Ci-C3o)hydrocarbyl interrupted by 0, 1, 2, or 3 groups independently chosen from -0-, -S-, substituted or unsubstituted -NH-, -(Si(OR^a)₂)m-, -(0-CH₂-CH₂)ni-, and -(0-CH₂-CH2-CH₂)ni-, wherein nl can be about 1 to about 1,000 (e.g., 1-100, 1-50, 1-10, 1, 2, 3, 4, 5, 6, 8, 10, 12, 14, 16, 18, 20, 25, 30, 40, 50, 75, 100, 200, 250, 500, 750, 1,000). The variable L^a can be an unsubstituted (Ci- C3o)hydrocarbyl interrupted by 0, 1, 2, or 3 groups independently chosen from -O- and -S-. The epoxy-functional organosiloxane can be 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, 3-glycidoxypropyl methyldimethoxysilane, 3-glycidoxypropyl trimethoxysilane, 3- glycidoxypropyl methyldiethoxysilane, or 3-glycidoxypropyl triethoxysilane. The flowable curable resin composition can include one epoxy-functional organosiloxane, or multiple epoxy-functional organo siloxane s. The one or more epoxy-functional organosiloxanes can be any suitable proportion of the flowable curable resin composition such as about 0.01 wt% to about 100 wt%, 10 wt% to about 100 wt%, about 50 wt% to about 99.9 wt%, or about 0.01 wt% or less, or about 0.1 wt%, 1, 2, 3, 4, 5, 6, 8, 10, 12, 14, 15, 20, 25, 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, 96, 97, 98, 99, 99.9, or about 99.99 wt%.

[0042] The organosiloxane including an isocyanate group can have the structure (R^b)4- pSi(R^c)_P. The variable p can be 1 to 4 (e.g., 1, 2, 3, or 4). At each occurrence, R^b can be independently chosen from substituted or unsubstituted (Ci-Cio)alkyl and substituted or unsubstituted (Ci-Cio)alkoxy. At each occurrence, R^b can be independently chosen from unsubstituted (Ci-Ce)alkyl and unsubstituted (Ci-Ce)alkoxy. At each occurrence, R^c can be - L^b-NCO, wherein L^b can be a substituted or unsubstituted (Ci-C3o)hydrocarbyl interrupted by 0, 1, 2, or 3 groups independently chosen from -0-, -S-, substituted or unsubstituted -NH-, - (Si(OR^b)2)n2-, -(0-CH2-CH2)n2-, and -(0-CH2-CH2-CH2)n2-, wherein n2 can be about 1 to about 1,000 (e.g., 1-100, 1-50, 1-10, 1, 2, 3, 4, 5, 6, 8, 10, 12, 14, 16, 18, 20, 25, 30, 40, 50, 75, 100, 200, 250, 500, 750, 1,000). At each occurrence, L^c can be an unsubstituted (Ci- C3o)hydrocarbyl interrupted by 0, 1, 2, or 3 groups independently chosen from -O- and -S-. The organosiloxane including the isocyanate group can be 3-isocyanatepropyltriethoxysilane. The flowable curable resin composition can include one or more than one organosiloxane including an isocyanate group. The one or more organosiloxanes including an isocyanate group can form any suitable proportion of the flowable curable resin composition, such as about 0.01 wt% to about 100 wt%, 10 wt% to about 100 wt%, about 50 wt% to about 99.9 wt%, or about 0.01 wt% or less, or about 0.1 wt%, 1, 2, 3, 4, 5, 6, 8, 10, 12, 14, 15, 20, 25, 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, 96, 97, 98, 99, 99.9, or about 99.99 wt%.

[0043] The organosiloxane including an isocyanurate group can have the structure:

[0044] At each occurrence, R^d can be chosen from -H and -L^c-Si(R^e)3, wherein at least one R^d is -L^c-Si(R^e)3. At each occurrence, R^d can be -L^c-Si(R^e)3. At each occurrence, L^c can be independently a substituted or unsubstituted (Ci-C3o)hydrocarbyl interrupted by 0, 1, 2, or 3 groups independently chosen from -0-, -S-, substituted or unsubstituted -NH-, -(Si(R^e)2)n3-, - (0-CH2-CH2)n3-, and -(0-CH2-CH2-CH2)n3-, wherein n3 can be about 1 to about 1,000 (e.g., 1-100, 1-50, 1-10, 1, 2, 3, 4, 5, 6, 8, 10, 12, 14, 16, 18, 20, 25, 30, 40, 50, 75, 100, 200, 250, 500, 750, 1,000). At each occurrence, L^c can be an unsubstituted (Ci-C3o)hydrocarbyl interrupted by 0, 1, 2, or 3 groups independently chosen from -O- and -S-. At each occurrence, R^e can be chosen from substituted or unsubstituted (Ci-Cio)alkyl and substituted or unsubstituted (Ci-Cio)alkoxy. At each occurrence, R^e can be independently chosen from unsubstituted (Ci-Ce)alkyl and unsubstituted (Ci-Ce)alkoxy. The organosiloxane including the isocyanate group or isocyanurate group can be tris-[3-(trimethoxysilyl propyl)- isocyanurate. The flowable curable resin composition can include one or multiple organosiloxanes including an isocyanurate group. Any suitable proportion of the flowable curable resin composition can be the one or more organosiloxanes including an isocyanurate group, such as about 0.01 wt% to about 100 wt%, 10 wt% to about 100 wt%, about 50 wt% to about 99.9 wt%, or about 0.01 wt% or less, or about 0.1 wt%, 1, 2, 3, 4, 5, 6, 8, 10, 12, 14, 15, 20, 25, 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, 96, 97, 98, 99, 99.9, or about 99.99 wt%.

[0045] The flowable curable resin composition can include a bis(organosiloxane)-functional amine. In some examples, the flowable curable resin composition includes an epoxy- functional organosiloxane, an organosiloxane comprising a isocyanate group or an isocyanurate group, and a bis(organosiloxane)-functional amine. The bis(organosiloxane)- functional amine can have the structure R^f3Si-L^d-NH-L^d-SiR^f3. At each occurrence, R^f can be chosen from substituted or unsubstituted (Ci-Cio)alkyl and substituted or unsubstituted (Ci- Cio)alkoxy. At each occurrence, R^f can be independently chosen from unsubstituted (Ci- C6)alkyl and unsubstituted (Ci-Ce)alkoxy. At each occurrence, L^d can be independently a substituted or unsubstituted (Ci-C3o)hydrocarbyl interrupted by 0, 1, 2, or 3 groups independently chosen from -0-, -S-, substituted or unsubstituted -NH-, -(Si(R^f)2)n4-, -(O-CH2- CH2)n4-, and -(O-Qrh-Qrh-QrhV-, wherein n4 can be about 1 to about 1,000 (e.g., 1-100, 1- 50, 1-10, 1, 2, 3, 4, 5, 6, 8, 10, 12, 14, 16, 18, 20, 25, 30, 40, 50, 75, 100, 200, 250, 500, 750, 1,000). At each occurrence, L^d can be an unsubstituted (Ci-C3o)hydrocarbyl interrupted by 0, 1, 2, or 3 groups independently chosen from -O- and -S-. The bis(organosiloxane)-functional amine can be bis(triethoxysilylpropyl)amine, bis(trimethoxysilylpropyl)amine, or bis(methyldiethoxysilylpropyl) amine. The flowable curable resin composition can include one or more bis(organosiloxane)-functional amines. The one or more bis(organosiloxane)- functional amines can form any suitable proportion of the flowable curable resin

composition, such as about 0.01 wt% to about 100 wt%, 10 wt% to about 100 wt%, about 50 wt% to about 99.9 wt%, or about 0.01 wt% or less, or about 0.1 wt%, 1, 2, 3, 4, 5, 6, 8, 10, 12, 14, 15, 20, 25, 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, 96, 97, 98, 99, 99.9, or about 99.99 wt%.

[0046] The method can include performing a hydrolysis and condensation reaction using water and a catalyst to form a sol (e.g., colloidal suspension), releasing alcohol or water. The sol can include the flowable curable resin composition. Coating the surface of the solid plastic form can include coating the solid plastic form with the sol. Curing the curable coating composition can include curing the sol on the plastic form, to provide the hardened film (e.g., gel) on the solid plastic form surface.

[0047] The flowable curable coating composition can include an alicyclic epoxy group- containing siloxane resin. The flowable curable coating composition can include one type of alicyclic epoxy group-containing siloxane resin or multiple types of such resin. The one or more alicyclic epoxy group-containing siloxane resin can form any suitable proportion of the flowable curable coating composition, such as about 0.01 wt% to about 100 wt%, 10 wt% to about 100 wt%, about 50 wt% to about 99.9 wt%, or about 0.01 wt% or less, or about 0.1 wt%, 1, 2, 3, 4, 5, 6, 8, 10, 12, 14, 15, 20, 25, 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, 96, 97, 98, 99, 99.9, or about 99.99 wt%. The siloxane resin can have a weight average molecular weight of about 1,000 to about 4,000 (e.g., about 1,000, 1,200, 1,400, 1,600, 1,800, 2,000, 2,200, 2,400, 2,600, 2,800, 3,000, 3,200, 3,400, 3,600, 3,800, or 4,000) and a (Mw/Mn) (i.e., weight average molecular weight divided by number average molecular weight, also referred to as polydispersity, a measure of the heterogeneity of sizes of molecules in the mixture) of about 1.05 to about 1.4 (e.g., about 1.05, 1.2, 1.4, 1.6, 1.8, 2.0, 2.2, 2.4, 2.6, 2.8, 3.0, 3.2, 3.4, 3.6, 3.8, or about 4.0 or more).

[0048] The siloxane resin can be prepared by hydrolysis and condensation, in the presence of water and an optional catalyst, of (i) an alkoxysilane including an alicyclic epoxy group and an alkoxy group having the structure R¹nSi(OR²)4-n alone, wherein R¹ is (C3- C6)cycloalkyl(Ci-C6)alkyl wherein the cycloalkyl group includes an epoxy group, R² is (Cl- C7)alkyl, and n is 1-3, or (ii) the alkoxysilane having the structure R¹nSi(OR²)4-n and an alkoxysilane having the structure R³mSi(OR⁴)4-m, wherein R³ is chosen from (Ci-C2o)alkyl, (C3-C8)cycloalkyl, (C2-C2o)alkenyl, (C2-C20)alkynyl, (C6-C2o)aryl, an acryl group, a methacyl group, a halogen group, an amino group, a mercapto group, an ether group, an ester group, a carbonyl group, a carboxyl group, a vinyl group, a nitro group, a sulfone group, and an alkyd group, R⁴ is (Ci-Cv)alkyl, and m is 0 to 3. The alkoxysilane having the structure R¹nSi(OR²)4- n can be 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane or 2-(3,4- epoxy cyclohexyl)ethyltriethoxysilane. The alkoxysilane having the structure R³mSi(OR⁴)4-m can be one or more chosen from tetramethoxysilane, tetraethoxysilane,

methyltrimethoxysilane, methyltriethoxysilane, methyltripropoxysilane,

dimethyldimethoxysilane, dimethyldiethoxysilane, phenyltrimethoxysilane,

phenyltriethoxysilane, diphenyldimethoxysilane, diphenyldiethoxysilane,

triphenylmethoxysilane, triphenylethoxysilane, ethyltriethoxysilane,

propylethyltrimethoxysilane, vinyltrimethoxysilane, vinyltriethoxysilane,

vinyltripropoxysilane, N-(3-acryloxy-2-hydroxypropyl)-3-aminopropyltrimethoxysilane, N- (3-acryloxy-2-hydroxypropyl)-3-aminopropyltriethoxysilane, N-(3-acryloxy-2- hydroxypropyl)-3 -aminopropyltripropoxysilane, 3 -aery loxypropylmethy Ibis (trimethoxy) silane, 3-acryloxypropyltrimethoxysilane, 3-acryloxypropyltriethoxysilane, 3- acryloxypropyltripropoxysilane, 3-(meth)acryloxypropyltrimethoxysilane, 3- (meth)acryloxypropyltriethoxysilane, 3 -(meth)acryloxypropyltripropoxysilane, N- (aminoethyl-3 -aminopropyl)trimethoxysilane, N-(2-aminoethyl-3 - aminopropyl)triethoxysilane, 3 -aminopropyltrimethoxysilane, 3 -aminopropyltriethoxy silane, chloropropyltrimethoxysilane, chloropropyltriethoxysilane, and

heptadecafluorodecyltrimethoxysilane.

[0049] The flowable curable coating composition can further include a reactive monomer capable of reacting with the alicyclic epoxy group to form crosslinking. The flowable curable coating composition can include one such monomer or multiple such monomers. The one or more reactive monomers can form any suitable proportion of the flowable curable coating composition, such as about 0.001 wt% to about 30 wt%, or about 0.01 wt% to about 10 wt%, or about 0.001 wt% or less, or about 0.01 wt%, 0.1, 1, 2, 3, 4, 5, 6, 8, 10, 12, 14, 16, 18, 20, 22, 24, 26, 28, or about 30 wt% or more. The one or more reactive monomer can be present in any suitable weight ratio to the epoxy-containing siloxane resin, such as about 1 : 1000 to about 1 : 10, or about 1 : 1000 or less, or about 1 :500, 1 :250, 1 :200, 1 : 150, 1 : 100, 1 :80, 1 :60, 1 :40, 1 :20, or about 1 : 10 or more. The reactive monomer can be an acid anhydride monomer, an oxetane monomer, or a monomer having an alicyclic epoxy group as a (C3-C6)cycloalkyl group. The acid anhydride monomer can be one or more chosen from phthalic anhydride, tetrahydrophthalic anhydride, hexahydrophthalic anhydride, nadic methyl anhydride, chlorendic anhydride, and pyromellitic anhydride. The oxetane monomer can be one or more chosen from 3-ethyl-3-hydroxymethyloxetane, 2-ethylhexyloxetane, xylene bis oxetane, and 3-ethyl-3[[3-ethyloxetan-3-yl]methoxy]oxetane. The reactive monomer having an alicyclic epoxy group can be one or more chosen from 4-vinylcycloghexene dioxide, cyclohexene vinyl monoxide, (3,4-epoxycyclohexyl)methyl 3,4-epoxycyclohexylcarboxylate, 3,4-epoxycyclohexylmethyl methacrylate, and bis(3,4-epoxycyclohexylmethyl)adipate.

[0050] In various examples, one or more catalysts are present. In other examples, the flowable curable coating composition can be free of catalyst. The catalyst can be any suitable catalyst, such as acidic catalysts, basic catalysts, ion exchange resins, and combinations thereof. For example, the catalyst can be hydrochloric acid, acetic acid, hydrogen fluoride, nitric acid, sulfuric acid, chlorosulfonic acid, iodic acid, pyrophosphoric acid, ammonia, potassium hydroxide, sodium hydroxide, barium hydroxide, imidazole, and combinations thereof.

[0051] The curable flowable coating composition can include one or more organic solvents, such as in an amount of about 0.01 to about 10 parts by weight, based on 100 parts by weight of the siloxane resin, or about 0.1 to about 10 parts by weight. The one or more solvents can be about 0.001 wt% to about 50 wt% of the curable flowable coating composition, about 0.01 wt% to about 30 wt%, about 30 wt% to about 70 wt%, or about 0.001 wt% or less, or about 0.01 wt%, 0.1, 1, 2, 3, 4, 5, 6, 8, 10, 12, 14, 16, 18, 20, 22, 24, 26, 28, 30, 35, 40, 45 wt%, or about 50 wt% or more.

[0052] The flowable curable coating composition can further includes one or more polymerization initiators chosen from UV initiators, thermal initiators, onium salts, organometallic salts, amines, and imidazoles in an amount of about 0.01 to about 10 parts by weight, based on 100 parts by weight of the siloxane resin, or about 0.1 to about 10 parts by weight. The one or more polymerization initiators can be about 0.001 wt% to about 50 wt% of the curable flowable coating composition, about 0.01 wt% to about 30 wt%, or about 0.001 wt% or less, or about 0.01 wt%, 0.1, 1, 2, 3, 4, 5, 6, 8, 10, 12, 14, 16, 18, 20, 22, 24, 26, 28, 30, 35, 40, 45 wt%, or about 50 wt% or more.

[0053] The flowable curable coating composition can further include one or more additives, such as chosen from an antioxidant, a leveling agent, an antifogging agent, an antifouling agent, and a coating control agent.

[0054] The method can also include curing the curable coating composition, to provide a hardened film on the solid plastic form surface. The curing can be any suitable curing. The curing can be thermal curing. The curing can be UV curing. The curing can be a combination of thermal and UV curing (e.g., in parallel or sequential).

[0055] The hardened film on the solid plastic form can have any suitable thickness, such as about 1 micron to about 1,000 microns, about 1 micron to about 100 microns, about 5 microns to about 75 microns, or about 1 micron, 2, 3, 4, 5, 6, 8, 10, 12, 14, 16, 18, 20, 25, 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, 100, 200, 500, 750, or about 1,000 microns or more.

[0056] The hardened film on the solid plastic form surface can have any suitable hardness. For example, the hardened film on the solid plastic form surface can have a hardness of about 3B to about 9H, or about HB to about 8H, or about 3B or less, or about 2B, B, HB, F, H, 2H, 3H, 4H, 5H, 6H, 7H, 8H, or about 9H or more.

[0057] With reference to FIG. 4, according to the disclosure, quantum dot solution 400 is formed by introducing a hyperbranched polymer 402 with a resin 404 to disperse quantum dots 406 therein. As schematically shown, hyperbranched polymer 402 is a macromolecule having a high number of branches 408 with a large number of end groups 410. The highly branched structure interacts with quantum dot ligands 412 to hold disperse quantum dots 406 a dispersion distance D relative to each other. The dispersion distance D may be greater than 2 nanometers and less than 9 nanometers. According to another example, the distance D is between 5 and 8 nanometers. According to another example, the distance D is 6 nanometers. In other examples, distances greater than or equal to about 10 nanometers are used to remove the FRET effect (FIG. 1). A variety of hyperbranched polymers may be used and the following examples should not be considered limiting.

[0058] In one example, a hyperbranched polymer having alkyl chain as an end group is used. In this example, the alkyl chain of the polymer can have a noncovalent interaction with alkyl chain of a quantum dot ligand.

[0059] In a second example, a hyperbranched polymer having amine, thiol, carboxylic acid, TOPO group can directly bind to the surface of quantum dots.

[0060] In a third example, amphiphilic hyperbranched polymer is used. The hydrophobic part of this polymer offers good comparability with the quantum dots.

[0061] In a fourth example, hyperbranched acrylates or epoxy are used based on good miscibility with a host resin.

[0062] FIG. 5 shows a method 500 according to an example of the present disclosure. The method may comprise preparing a hyperbranched polymer and quantum dot mixture to form the quantum dot solution at step 502; adding a host resin at step 503; and disposing the quantum dot solution on a first layer 202, which as shown in FIG. 2 may be a barrier film, at step 504. The quantum dot solution may be disposed on the barrier film using a solution coating process including but not limited to roll coating , gravure coating, knife coating, dip coating, curtain flow coating, spray coating, bar coating, die coating, spin coating or inkjet coating, by using a dispenser, or a combination thereof.

[0063] Preparation of the quantum dot solution at 502 may include any of the examples discussed above in connection with FIG. 4. Mixture of the quantum dots and hyperbranched polymer at 502 may simply adding quantum dots to a hyperbranched solution. The hyperbranched polymer may be dissolved or otherwise dispersed in a solution to facilitate this process. According to one example a hyperbranched polymer is placed in a solvent to form a solution containing hyperbranched polymer and then quantum dots are added to this solution and mixed. In one example, toluene is used to dissolve the hyperbranched polymer. In this example, temperature and pressure may be simply room temperature and atmospheric pressure. In other examples, temperature and pressure may be varied to facilitate mixing. Mixing may include stirring or other agitation. In one example, a magnetic stirrer is used. Depending on the type of polymer and solvent used, once the hyperbranched polymer and quantum dot mixing is suitable, the solvent may be removed from the mixture before disposing the quantum dot solution at step 504.

[0064] In the example shown in FIG. 5, hyper branched polymer and quantum dots are mixed with a resin to form a flowable coating that is applied to first layer 202 as discussed above. At step 506, the quantum dot solution may be cured to form a quantum dot layer 206 adhered to the first layer 202. The quantum dot layer 206 may be cured using one or more of a radiation curing process including but not limited to a ultraviolet (UV) curing process or electron ray process, and a thermal curing process including but not limited to a steam curing process. A second layer 204 comprising a barrier film may be laminated to quantum dot layer 206 at step 508. Each barrier film may comprise a polysilazane-based polymer, a polysiloxane-based polymer, or a combination thereof.

[0065] Additional functional layers including but not limited to the solid plastic coatings and films described above, prisms layers, diffuser layers, matt finish layers and other surface treatments may be applied outward of barrier film, as depicted in FIG. 3. Application of such layers may occur before or after assembly of the first layer, second layer and quantum dot layer as depicted in steps 502 through 508.

[0066] In accordance with the disclosures above, sample compositions of resin and a hyperbranched polymer and quantum dot mixture were considered. Sample 1 contained 95% resin and 5% hyperbranched polymer mixture; sample 2 contained 90% resin and 10% hyperbranched polymer mixture; sample 3 contained 80% resin and 20% hyperbranched polymer mixture; and sample 4 contained 70% resin and 30% hyperbranched polymer mixture (as summarized in Table 1). Composition (wt%) Sample 1 Sample 2 Sample 3 Sample 4

Main resin 95 90 80 70

Hyperbranched polymer 5 10 20 30

Total (%) 100 100 100 100

Table 1. Composition of resin according to the content of hyperbranched aery late

[0067] Expected external quantum efficiencies (EQE, in %) of the sample compositions were compared to a conventional quantum dot film, with the following results:

Table 2. Expected EQE of samp e compositions to conventional QD film

[0068] External quantum efficiency is expected to improve relative to conventional quantum dot film in all of the samples. Increasing the proportion of hyperbranched polymer and quantum dot mixture relative to the resin is expected to increase relative to a conventional QD film to a point and then decrease. Table 2 suggests that a maximum efficiency is obtained near a hyperbranched polymer mixture percentage of 20% to 30%. Within this range, the external quantum efficiency is expected to decrease toward the 30%

hyperbranched polymer mixture concentration. Beyond 30% concentration of hyperbranched polymer mixture, the external quantum efficiency may continue to drop below the level attributed to a conventional QD film. Consequently, a concentration of 30% to 35% of hyperbranched polymer mixture in 70% to 65% resin is expected to produce external quantum efficiencies comparable to conventional QD film. Concentrations of hyperbranched polymers less than or equal to about 30% and greater than 0% are expected to yield greater external quantum efficiencies than conventional QD film. Concentrations of hyperbranched polymer in the range of about 5% to about 30% are expected to exhibit improved external quantum efficiency with concentrations from about 10% to about 20% producing the greatest increase in quantum efficiency.

Examples

[0069] The present disclosure comprises at least the following examples.

[0070] Example 1. A light emitting film comprising a first layer and a second layer; a quantum dot layer disposed between the first layer and the second layer; and wherein the quantum dot layer is formed from a quantum dot solution comprising a mixture of hyperbranched polymer, resin and quantum dots.

[0071] Example 2. The film of example 1, wherein the mixture includes greater than 0% and no more than 35% hyperbranched polymer.

[0072] Example 3. The film of any one examples 1-2, wherein the mixture includes from about 5% to about 30% hyperbranched polymer.

[0073] Example 4. The film of any one examples 1-3, wherein the mixture includes from about 10% to about 20% hyperbranched polymer.

[0074] Example 5. The film of examples 1-4, wherein the mixture includes about 20% hyperbranched polymer.

[0075] Example 6. The film of any one of examples 1-5, wherein the hyperbranched polymer has an alkyl chain as an end group.

[0076] Example 7. The film of any one of examples 1-5, wherein the hyperbranched polymer has an amine, thiol, carboxylic acid, TOPO group adapted to directly bind to the surface of quantum dots.

[0077] Example 8. The film of any one of examples 1-5, wherein the hyperbranched polymer is an amphiphilic hyperbranched polymer.

[0078] Example 9. The film of any one of examples 1-5, wherein the hyperbranched polymer includes at least one of hyperbranched acrylates and epoxy.

[0079] Example 10. The film of any one of examples 1-6, wherein the first layer and the second layer each include barrier films adjacent to the quantum dot layer.

[0080] Example 11. The film of any one of examples 1-7, further comprising a functional layer provided outward of at least one of the first layer and the second layer.

[0081] Example 12. The film of any one of examples 1-8, wherein the functional layer is a diffuser.

[0082] Example 13. The film of any one of examples 1-8, wherein the functional layer is a prism.

[0083] Example 14. The film of any one of examples 1-9, wherein the quantum dot is disposed on the first layer using a solution coating process.

[0084] Example 15. The film of example 14, wherein the solution coating process is selected from the group consisting of roll coating , gravure coating, knife coating, dip coating, curtain flow coating, spray coating, bar coating, die coating, spin coating, inkjet coating, and dispenser coating. [0085] Example 16. The film of any one of examples 1-15 wherein the quantum dots in the quantum dot layer are dispersed relative to each other by a distance of at least about 10 nanometers.

[0086] Example 17. A light emitting device comprising the film of any one of examples 1- 19.

[0087] Example 18. A film for light emitting devices, the film formed from a process comprising providing a first layer; mixing a hyperbranched polymer with quantum dots and a resin to form a quantum dot solution; disposing a quantum dot solution on the first layer to form a quantum dot layer; and disposing a second layer on the quantum dot layer.

[0088] Example 19. The film of example 18, further comprising the step of curing the quantum dot solution after it is disposed on the first layer.

[0089] Example 20. The film of examples 18-19 further comprising the step of disposing a functional layer outward of at least one of the first layer and the second layer.

[0090] Example 21. The film of example 20, wherein the functional layer is a diffuser.

[0091] Example 22. The film of example 20, wherein the functional layer is a prism.

[0092] Example 23. The film of any one examples 18-22, wherein the first layer is a barrier layer and the second layer is a barrier layer.

[0093] Example 24. The film of any one examples 18-23, wherein the quantum dot solution is disposed on the first layer using a solution coating process.

[0094] Example 25. The film of any one examples 19-24, wherein the solution coating process is selected from the group consisting of roll coating , gravure coating, knife coating, dip coating, curtain flow coating, spray coating, bar coating, die coating, spin coating, inkjet coating, and dispenser coating.

[0095] Example 26. The film of any one examples 18-25, wherein at least one of the layers is cured using one or more of a radiation curing process and a thermal curing process.

[0096] Example 27. The film of any one of examples 18-26, wherein the quantum dots in the quantum dot layer are dispersed relative to each other by a distance of greater than 2 nanometers and less than 9 nanometers.

[0097] Example 28. A light emitting device comprising the film of any one of examples 18- 27.

[0098] Example 29. A method comprising providing a first layer; mixing a hyperbranched polymer with quantum dots and a resin to form a quantum dot solution; disposing a quantum dot solution on the first layer to form a quantum dot layer; and disposing a second layer on the quantum dot layer. [0099] Example 30. The method of example 29, wherein the step of mixing includes adding greater than 0% and less than 35% hyperbranched polymer.

[00100] Example 31. The method of example 30, wherein the step of mixing includes adding from about 5% to about 30% hyperbranched polymer.

[00101] Example 32. The method of example 31, wherein the step of mixing includes adding from about 10% to about 20% hyperbranched polymer.

[00102] Example 33. The method of example 32, wherein the step of mixing includes adding about 20% hyperbranched polymer.

[00103] Example 34. The method of any one of examples 29-33, wherein the hyperbranched polymer has an alkyl chain as an end group.

[00104] Example 35. The method of any one of examples 29-33, wherein the hyperbranched polymer has an amine, thiol, carboxylic acid, TOPO group adapted to directly bind to the surface of quantum dots.

[00105] Example 36. The method of any one of examples 29-33, wherein the hyperbranched polymer is an amphiphilic hyperbranched polymer.

[00106] Example 37. The method of any one of examples 29-33, wherein the hyperbranched polymer includes at least one of hyperbranched acrylates and epoxy.

[00107] Example 38. The method of any of examples 29-37, wherein the quantum dots in the quantum dot solution are dispersed by a distance of at least about 10 nanometers.

Definitions

[00108] It is to be understood that the terminology used herein is for the purpose of describing particular examples only and is not intended to be limiting. As used in the specification and in the claims, the term "comprising" can include the aspects "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.

[00109] Throughout this document, values expressed in a range format should be interpreted in a flexible manner to include not only the numerical values explicitly recited as the limits of the range, but also to include all the individual numerical values or sub-ranges encompassed within that range as if each numerical value and sub-range is explicitly recited. For example, a range of "about 0.1% to about 5%" or "about 0.1% to 5%" should be interpreted to include not just about 0.1% to about 5%, but also the individual values (e.g., 1%, 2%, 3%, and 4%) and the sub-ranges (e.g., 0.1% to 0.5%, 1.1% to 2.2%, 3.3% to 4.4%) within the indicated range. The statement "about X to Y" has the same meaning as "about X to about Y," unless indicated otherwise. Likewise, the statement "about X, Y, or about Z" has the same meaning as "about X, about Y, or about Z," unless indicated otherwise. The term "about" as used herein can allow for a degree of variability in a value or range, for example, within 10%, within 5%, or within 1% of a stated value or of a stated limit of a range, and includes the exact stated value or range. The term "substantially" as used herein refers to a majority of, or mostly, as in at least about 50%, 60%, 70%, 80%, 90%, 95%, 96%, 97%, 98%, 99%, 99.5%, 99.9%, 99.99%, or at least about 99.999% or more, or 100%.

[00110] In this document, the terms "a," "an," or "the" are used to include one or more than one unless the context clearly dictates otherwise. The term "or" is used to refer to a nonexclusive "or" unless otherwise indicated. The statement "at least one of A and B" has the same meaning as "A, B, or A and B." In addition, it is to be understood that the phraseology or terminology employed herein, and not otherwise defined, is for the purpose of description only and not of limitation. Any use of section headings is intended to aid reading of the document and is not to be interpreted as limiting; information that is relevant to a section heading may occur within or outside of that particular section.

[00111] In the methods described herein, the acts can be carried out in any order without departing from the principles of the disclosure, except when a temporal or operational sequence is explicitly recited. Furthermore, specified acts can be carried out concurrently unless explicit claim language recites that they be carried out separately. For example, a claimed act of doing X and a claimed act of doing Y can be conducted simultaneously within a single operation, and the resulting process will fall within the literal scope of the claimed process.

[00112] The term "organic group" as used herein refers to any carbon-containing functional group. For example, an oxygen-containing group such as an alkoxy group, aryloxy group, aralkyloxy group, oxo(carbonyl) group, a carboxyl group including a carboxylic acid, carboxylate, and a carboxylate ester; a sulfur-containing group such as an alkyl and aryl sulfide group; and other heteroatom-containing groups. Non-limiting examples of organic groups include OR, OOR, OC(0)N(R)₂, CN, CF₃, OCF₃, R, C(O),

methylenedioxy, ethylenedioxy, N(R)₂, SR, SOR, SO2R, S0₂N(R)₂, SO3R, C(0)R,

C(0)C(0)R, C(0)CH₂C(0)R, C(S)R, C(0)OR, OC(0)R, C(0)N(R)₂, OC(0)N(R)₂, C(S)N(R)₂, (CH₂)o-₂N(R)C(0)R, (CH₂)o-₂N(R)N(R)₂, N(R)N(R)C(0)R, N(R)N(R)C(0)OR, N(R)N(R)CON(R)₂, N(R)S0₂R, N(R)S0₂N(R)₂, N(R)C(0)OR, N(R)C(0)R, N(R)C(S)R, N(R)C(0)N(R)₂, N(R)C(S)N(R)₂, N(COR)COR, N(OR)R, C(=NH)N(R)₂, C(0)N(OR)R, C(=NOR)R, and substituted or unsubstituted (Ci-Cioo)hydrocarbyl, wherein R can be hydrogen (in examples that include other carbon atoms) or a carbon-based moiety, and wherein the carbon-based moiety can be substituted or unsubstituted.

[00113] The term "substituted" as used herein in conjunction with a molecule or an organic group as defined herein refers to the state in which one or more hydrogen atoms contained therein are replaced by one or more non-hydrogen atoms. The term "functional group" or "substituent" as used herein refers to a group that can be or is substituted onto a molecule or onto an organic group. Examples of substituents or functional groups include, but are not limited to, a halogen (e.g., F, CI, Br, and I); an oxygen atom in groups such as hydroxy groups, alkoxy groups, aryloxy groups, aralkyloxy groups, oxo(carbonyl) groups, carboxyl groups including carboxylic acids, carboxylates, and carboxylate esters; a sulfur atom in groups such as thiol groups, alkyl and aryl sulfide groups, sulfoxide groups, sulfone groups, sulfonyl groups, and sulfonamide groups; a nitrogen atom in groups such as amines, hydroxyamines, nitriles, nitro groups, N-oxides, hydrazides, azides, and enamines; and other heteroatoms in various other groups. Non-limiting examples of substituents that can be bonded to a substituted carbon (or other) atom include F, CI, Br, I, OR, OC(0)N(R)2, CN, NO, NOi, ONO2, azido, CF3, OCF3, R, O (oxo), S (thiono), C(O), S(O), methylenedioxy, ethylenedioxy, N(R)₂, SR, SOR, SO2R, S0₂N(R)₂, SO3R, C(0)R, C(0)C(0)R,

C(0)CH₂C(0)R, C(S)R, C(0)OR, OC(0)R, C(0)N(R)₂, OC(0)N(R)₂, C(S)N(R)₂, (CH₂)o- ₂N(R)C(0)R, (CH₂)o-₂N(R)N(R)₂, N(R)N(R)C(0)R, N(R)N(R)C(0)OR, N(R)N(R)CON(R)₂, N(R)S0₂R, N(R)S0₂N(R)₂, N(R)C(0)OR, N(R)C(0)R, N(R)C(S)R, N(R)C(0)N(R)₂, N(R)C(S)N(R)₂, N(COR)COR, N(OR)R, C(=NH)N(R)₂, C(0)N(OR)R, and C(=NOR)R, wherein R can be hydrogen or a carbon-based moiety; for example, R can be hydrogen, (Ci- Cioo)hydrocarbyl, alkyl, acyl, cycloalkyl, aryl, aralkyl, heterocyclyl, heteroaryl, or heteroarylalkyl; or wherein two R groups bonded to a nitrogen atom or to adjacent nitrogen atoms can together with the nitrogen atom or atoms form a heterocyclyl.

[00114] The term "alkyl" as used herein refers to straight chain and branched alkyl groups and cycloalkyl groups. Examples of straight chain alkyl groups include those with from 1 to 8 carbon atoms such as methyl, ethyl, n-propyl, n-butyl, n-pentyl, n-hexyl, n-heptyl, and n-octyl groups. Examples of branched alkyl groups include, but are not limited to, isopropyl, iso-butyl, sec-butyl, t-butyl, neopentyl, isopentyl, and 2,2-dimethylpropyl groups.

[00115] The term "alkenyl" as used herein refers to straight and branched chain and cyclic alkyl groups as defined herein, except that at least one double bond exists between two carbon atoms. [00116] The term "acyl" as used herein refers to a group containing a carbonyl moiety wherein the group is bonded via the carbonyl carbon atom.

[00117] The term "cycloalkyl" as used herein refers to cyclic alkyl groups such as, but not limited to, cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cycloheptyl, and cyclooctyl groups. In some examples, the cycloalkyl group can have 3 to about 8-12 ring members, whereas in other examples the number of ring carbon atoms range from 3 to 4, 5, 6, or 7

[00118] The term "aryl" as used herein refers to cyclic aromatic hydrocarbon groups that do not contain heteroatoms in the ring. Thus aryl groups include, but are not limited to, phenyl, azulenyl, heptalenyl, biphenyl, indacenyl, fluorenyl, phenanthrenyl, triphenylenyl, pyrenyl, naphthacenyl, chrysenyl, biphenylenyl, anthracenyl, and naphthyl groups.

[00119] The term "heterocyclyl" as used herein refers to aromatic and non-aromatic ring compounds containing three or more ring members, of which one or more is a heteroatom such as, but not limited to, N, O, and S.

[00120] The term "alkoxy" as used herein refers to an oxygen atom connected to an alkyl group, including a cycloalkyl group, as are defined herein.

[00121] The terms "halo," "halogen," or "halide" group, as used herein, by themselves or as part of another substituent, mean, unless otherwise stated, a fluorine, chlorine, bromine, or iodine atom.

[00122] The term "haloalkyl" group, as used herein, includes mono-halo alkyl groups, poly-halo alkyl groups wherein all halo atoms can be the same or different, and per-halo alkyl groups, wherein all hydrogen atoms are replaced by halogen atoms, such as fluoro. Examples of haloalkyl include trifluoromethyl, 1, 1-dichloroethyl, 1,2-dichloroethyl, l,3-dibromo-3,3- difluoropropyl, perfluorobutyl, and the like.

[00123] The term "hydrocarbon" or "hydrocarbyl" as used herein refers to a molecule or functional group, respectively, that includes carbon and hydrogen atoms. The term can also refer to a molecule or functional group that normally includes both carbon and hydrogen atoms but wherein all the hydrogen atoms are substituted with other functional groups.

[00124] As used herein, the term "hydrocarbyl" refers to a functional group derived from a straight chain, branched, or cyclic hydrocarbon, and can be alkyl, alkenyl, alkynyl, aryl, cycloalkyl, acyl, or any combination thereof. Hydrocarbyl groups can be shown as (Ca- Cb)hydrocarbyl, wherein a and b are integers and mean having any of a to b number of carbon atoms. For example, (Ci-C4)hydrocarbyl means the hydrocarbyl group can be methyl (Ci), ethyl (C2), propyl (C3), or butyl (C₄), and (Co-Cb)hydrocarbyl means in certain examples there is no hydrocarbyl group. [00125] The term "number-average molecular weight" (M_n) as used herein refers to the ordinary arithmetic mean of the molecular weight of individual molecules in a sample. It is defined as the total weight of all molecules in a sample divided by the total number of molecules in the sample. Experimentally, M_n is determined by analyzing a sample divided into molecular weight fractions of species i having m molecules of molecular weight Mi through the formula M_n =∑Maii /∑m. The M_n can be measured by a variety of well-known methods including gel permeation chromatography, spectroscopic end group analysis, and osmometry. If unspecified, molecular weights of polymers given herein are number-average molecular weights.

[00126] The term "weight-average molecular weight" as used herein refers to M_w, which is equal to∑Mi¾ /∑Mmi, where m is the number of molecules of molecular weight Mi. In various examples, the weight-average molecular weight can be determined using light scattering, small angle neutron scattering, X-ray scattering, and sedimentation velocity.

[00127] The term "radiation" as used herein refers to energetic particles travelling through a medium or space. Examples of radiation are visible light, infrared light, microwaves, radio waves, very low frequency waves, extremely low frequency waves, thermal radiation (heat), and black-body radiation.

[00128] The term "UV light" as used herein refers to ultraviolet light, which is electromagnetic radiation with a wavelength of about 10 nm to about 400 nm.

[00129] The term "cure" as used herein refers to exposing to radiation in any form, heating, or allowing to undergo a physical or chemical reaction that results in hardening or an increase in viscosity.

[00130] The term "solvent" as used herein refers to a liquid that can dissolve a solid, liquid, or gas. Non-limiting examples of solvents are silicones, organic compounds, water, alcohols, ionic liquids, and supercritical fluids.

[00131] The term "coating" as used herein refers to a continuous or discontinuous layer of material on the coated surface, wherein the layer of material can penetrate the surface and can fill areas such as pores, wherein the layer of material can have any three-dimensional shape, including a flat or curved plane. In one example, a coating can be formed on one or more surfaces, any of which may be porous or nonporous, by immersion in a bath of coating material.

[00132] The term "surface" as used herein refers to a boundary or side of an object, wherein the boundary or side can have any perimeter shape and can have any three- dimensional shape, including flat, curved, or angular, wherein the boundary or side can be continuous or discontinuous. While the term surface generally refers to the outermost boundary of an object with no implied depth, when the term 'pores' is used in reference to a surface, it refers to both the surface opening and the depth to which the pores extend beneath the surface into the substrate.

[00133] As used herein, the term "polymer" refers to a molecule having at least one repeating unit and can include copolymers.

[00134] The polymers described herein can terminate in any suitable way. In some examples, the polymers can terminate with an end group that is independently chosen from a suitable polymerization initiator, -H, -OH, a substituted or unsubstituted (Ci-C2o)hydrocarbyl (e.g., (Ci-Cio)alkyl or (C6-C2o)aryl) interrupted with 0, 1, 2, or 3 groups independently selected from -0-, substituted or unsubstituted -NH-, and -S-, a poly(substituted or unsubstituted (Ci-C2o)hydrocarbyloxy), and a poly(substituted or unsubstituted (Ci- C2o)hydrocarbylamino) .

[00135] Illustrative types of polyethylene include, for example, ultra-high molecular weight polyethylene (UHMWPE), ultra-low molecular weight polyethylene (ULMWPE), high molecular weight polyethylene (HMWPE), high density polyethylene (HDPE), high density cross-linked polyethylene (HDXLPE), cross-linked polyethylene (PEX or XLPE), medium density polyethylene (MDPE), low density polyethylene (LDPE), linear low density polyethylene (LLDPE) and very low density polyethylene (VLDPE).

Claims

CLAIMS What is claimed is:

1. A light emitting film comprising:

a first layer,

a second layer; and

a quantum dot layer disposed between the first layer and the second layer, wherein the quantum dot layer is formed from a quantum dot solution comprising a mixture of hyperbranched polymer, resin and quantum dots.

2. The film of claim 1, wherein the mixture includes greater than 0% and no more than 35% hyperbranched polymer.

3. The film of any one of claims 1-2, wherein the mixture includes from about 5% to about 30% hyperbranched polymer.

4. The film of any one of claims 1-3, wherein the mixture includes from about 10% to about 20% hyperbranched polymer.

5. The film of any one of claims 1-4, wherein the mixture includes about 20% hyperbranched polymer.

6. The film of any one of claims 1-5, wherein the hyperbranched polymer has an alkyl chain as an end group.

7. The film of any one of claims 1-5, wherein the hyperbranched polymer has an amine, thiol, carboxylic acid, TOPO group adapted to directly bind to a surface of quantum dots.

8. The film of any one of claims 1-5, wherein the hyperbranched polymer is an amphiphilic hyperbranched polymer.

9. The film of any one of claims 1-5, wherein the hyperbranched polymer includes at least one of hyperbranched acrylates and epoxy.

10. The film of any one of claims 1-6, wherein the first layer and the second layer each include barrier films adjacent to the quantum dot layer.

11. The film of any one of claims 1-7, further comprising a functional layer provided outward of at least one of the first layer and the second layer.

12. The film of claim 11, wherein the functional layer is a diffuser.

13. The film of claim 11, wherein the functional layer is a prism.

14. The film of any one of claims 1-9, wherein the quantum dot layer is disposed on the first layer using a solution coating process.

15. The film of claim 14, wherein the solution coating process is selected from the group consisting of roll coating , gravure coating, knife coating, dip coating, curtain flow coating, spray coating, bar coating, die coating, spin coating, inkjet coating, and dispenser coating.

16. The film of any one of claims 1-15, wherein the quantum dots in the quantum dot layer are dispersed relative to each other by a distance at least about 10 nanometers.

17. A light emitting device comprising the film of any one of claims 1-16.

18. A film for light emitting devices, the film formed from a process comprising:

providing a first layer;

mixing a hyperbranched polymer with quantum dots and a resin to form a quantum dot solution;

disposing a quantum dot solution on the first layer to form a quantum dot layer; and disposing a second layer on the quantum dot layer.

19. The film of claim 18, further comprising the step of curing the quantum dot solution after disposing the quantum dot solution on the first layer.

20. The film of either of claims 18 or 19, further comprising the step of disposing a functional layer outward of at least one of the first layer and the second layer.