TWI782270B - Quantum dot film and method of making the same - Google Patents

Abstract

A quantum dot film includes a plurality of sealed microcells. The microcells may be formed within a layer of polymeric material and sealed with a sealing material. Also, the microcells may contain a dispersion of a solvent and a plurality of quantum dots. A method of making a quantum dot film includes providing a layer of polymeric material having a plurality of open microcells, filling the plurality of open microcells with a dispersion of a solvent and plurality of quantum dots, and sealing the microcells.

Description

Quantum dot thin film and its manufacturing method

This application is related to and claims priority to U.S. Provisional Application Serial No. 62/568,909, filed October 6, 2017. The entire disclosure of the above application is hereby incorporated by reference.

The present invention relates to quantum dot films. More particularly, one aspect of the invention relates to display systems that include quantum dot films. Another aspect of the present invention relates to a method for manufacturing a quantum dot thin film.

Quantum dots are particles made of nanomaterials that emit light at specific frequencies when electric current or light is applied. The frequency of light emitted by quantum dots can be varied by changing the dot size, shape, and material type. One application of quantum dots due to their improved color accuracy is optoelectronic displays, specifically LED displays.

The term "optoelectronic" as applied to materials or displays is used herein in its conventional sense in the imaging arts to refer to a material having at least one optically distinct first and second display state which is transformed by the application of an electric field to the material. Changes from its first to second display state. While this optical property is generally the color perceived by the naked human eye, it may be other optical properties such as optical transmittance, reflectivity, luminescence, or in the case of displays intended for machine reading, electromagnetic waves outside the range of visible light The long-term reflectance change is called false color.

Quantum dots are often incorporated into LED displays by being provided in the form of a film sandwiched between a backlight unit and a red-green-blue (RGB) color filter. The backlight unit includes blue LEDs, and part of the emitted blue light is converted into red and green light after passing through the quantum dot film. Thus, the light exiting the quantum dot film and entering the color filter includes substantially incremental red, green or blue light. As a result, the amount of light absorbed by the color filter is reduced.

Quantum dot films are fabricated by blending quantum dots in a polymer, such as epoxy, and applying a barrier layer on either side of the polymer-quantum dot blend layer. A curable polymer and barrier layer seals the quantum dots from oxygen and water, which degrades the material over time. However, mixing quantum dots with polymers often has inherent difficulties, such as homogeneity, dispersion force, and loss of performance (quantum yield and reliability). Therefore, there is a need for improved quantum dot thin films.

According to the first embodiment of the present invention, the quantum dot film may include a plurality of sealed cells. The cells may be formed within a layer of polymeric material and sealed by a sealing material. In addition, the micelles may contain a dispersion liquid including a solvent and a plurality of quantum dots.

According to a second embodiment of the present invention, a method of manufacturing a quantum dot thin film may include providing a layer of polymeric material having a plurality of open cells, filling the plurality of open cells with a dispersion comprising a solvent and a plurality of quantum dots , and seal the microcell.

These and other aspects of the present invention will be apparent from the following description.

In the following detailed description, numerous specific details are set forth by way of example in order to provide a thorough understanding of the relevant teachings. However, it will be apparent to those skilled in the art that the present teachings can be practiced without such details.

Various embodiments of the present invention generally provide an improved quantum dot film by eliminating polymer/quantum dot blends. Films according to various embodiments of the present invention encapsulate quantum dot films in a plurality of sealed cells. Quantum dot dispersions can be encapsulated in optical films using various methods. Materials incorporated into display systems, for example, have been described in numerous patents and applications assigned to or in the name of Massachusetts Institute of Technology (MIT), E Ink Corporation, E Ink California, LLC, and related companies. Various technologies use encapsulation and microcell electrophoretic media as well as other optoelectronic media. The technologies disclosed in these patents and applications include the following, which are hereby incorporated by reference in their entirety: (a) Electrophoretic particles, fluids and fluid additives; see, eg, US Patent Nos. 7,002,728 and 7,679,814; (b) Capsules, adhesives, and methods of encapsulation; see, eg, U.S. Patent Nos. 6,922,276 and 7,411,719; (c)微胞結構、壁材料、及形成微胞之方法；參見例如美國專利第6,672,921、6,751,007、6,753,067、6,781,745、6,788,452、6,795,229、6,806,995、6,829,078、6,833,177、6,850,355、6,865,012、6,870,662、6,885,495、6,906,779、 6,930,818、6,933,098、6,947,202、6,987,605、7,046,228、7,072,095、7,079,303、7,141,279、7,156,945、7,205,355、7,233,429、7,261,920、7,271,947、7,304,780、7,307,778、7,327,346、7,347,957、7,470,386、7,504,050、7,580,180、7,715,087、7,767,126、7,880,958、8,002,948、8,154,790、 8,169,690、8,441,432、8,582,197、8,891,156、9,279,906、9,291,872、及9,388,307號，以及美國專利申請案公開第2003/0175480、2003/0175481、2003/0179437、2003/0203101、2013/0321744、2014/0050814、2015/0085345 , 2016/0059442, 2016/0004136, and 2016/0059617; (d)填充及密封微胞之方法；參見例如美國專利第6,545,797、6,751,008、6,788,449、6,831,770、6,833,943、6,859,302、6,867,898、6,914,714、6,972,893、7,005,468、7,046,228、7,052,571、7,144,942、7,166,182、7,374,634、7,385,751、7,408,696、 7,522,332、7,557,981、7,560,004、7,564,614、7,572,491、7,616,374、7,684,108、7,715,087、7,715,088、8,179,589、8,361,356、8,520,292、8,625,188、8,830,561、9,081,250、及9,346,987號，以及美國專利申請案公開第2002/0188053、2004/0120024、2004 /0219306, 2006/0132897, 2006/0164715, 2006/0238489, 2007/0035497, 2007/0036919, 2007/0243332, 2015/0098124, and 2016/0109780; (e)含有光電材料之膜及次組裝件；參見例如美國專利第6,825,829、6,982,178、7,112,114、7,158,282、7,236,292、7,443,571、7,513,813、7,561,324、7,636,191、7,649,666、7,728,811、7,729,039、7,791,782、7,839,564、7,843,621、7,843,624、 8,034,209、8,068,272、8,077,381、8,177,942、8,390,301、8,482,835、8,786,929、8,830,553、8,854,721、9,075,280、及9,238,340號，以及美國專利申請案公開第2007/0237962、2009/0109519、2009/0168067、2011/0164301、2014/0115884 , and No. 2014/0340738; (f) backplanes, adhesive layers, and other auxiliary layers and methods for displays; see, for example, US Patent Nos. 7,116,318 and 7,535,624; (g) Color formation and color adjustment; see, eg, US Patent Nos. 7,075,502 and 7,839,564; (h) methods of driving displays; see for example US Patent Nos. 7,012,600 and 7,453,445; (i) Display applications; see, eg, US Patent Nos. 7,312,784 and 8,009,348; and (j) Non-electrophoretic displays, as disclosed in U.S. Patent No. 6,241,921 and U.S. Patent Application Publication No. 2015/0277160; and packaging and cellular technology applications other than displays; see, e.g., U.S. Patent Application Publication Nos. 2015/0005720 and 2016/0012710.

Referring now to FIG. 1, a quantum dot film 10 according to a first embodiment of the present invention is depicted. The quantum dot film 10 may comprise a layer of light-transmitting polymer material 11 that has been embossed, eg, with a microcellular pattern. The pattern can provide a plurality of cells in various geometric configurations, such as circles, ellipses, cubes, hexagons and the like. Each microcell is preferably a homogeneous dispersion of quantum dots 18 and 19 in a solvent 16 (preferably a liquid). The dispersion liquid is sealed in the cells by the light-transmitting sealing layer 14 (preferably made of curable material). The refractive indices of the polymeric material 11, the solvent 16, and the sealing layer 14 are preferably very close.

A layer of polymeric material having a plurality of cells may include, but is not limited to, thermoplastic or thermoset materials or their precursors, such as multifunctional vinyls, which include, but are not limited to, acrylates, methacrylates, allyls, Vinylbenzenes, vinyl ethers, polyfunctional epoxides and oligomers or their polymers, etc. It often uses multifunctional acrylates and their oligomers. Combinations of polyfunctional epoxides and polyfunctional acrylates can also be used to obtain the desired physical-mechanical properties of the micelles. Flexibility-imparting low Tg (glass transition temperature) adhesives or cross-linkable oligomers such as urethane acrylate or polyester acrylate can also be added to improve the bending resistance of the film.

A layer of polymeric material comprising a plurality of cells provides a flexible substrate so that the cells can be filled with a dispersion containing quantum dots using various printing or coating techniques, some of which are not necessarily expensive. (The use of the word "printing" is intended to include all forms of printing and coating, including but not limited to: pre-metered coating such as die coating, slot or extrusion coating, slip or waterfall coating, Curtain coating; roll coating, such as knife roll coating, forward and reverse roll coating; gravure coating; dip coating; spray coating; liquid surface coating; spin coating; brush coating; Pneumatic blade coating; screen printing method; electrostatic printing method; thermal printing method; inkjet printing method; electrophoretic deposition (see U.S. Patent No. 7,339,715); Being flexible, the film can be incorporated into flexible displays.

The polymeric material may also comprise polar oligomeric or polymeric material. This polar oligomeric or polymeric material can be selected from having at least one such as nitro (-NO2), hydroxyl (-OH), carboxyl (-COO), alkoxy (-OR, wherein R is alkyl), halo ( For example, a group consisting of oligomers or polymers based on fluorine, chlorine, bromine, or iodine), cyano (-CN), sulfonic acid (-SO3) and the like. The glass transition temperature of the polar polymeric material is preferably less than about 100°C, and more preferably less than about 60°C. Specific examples of suitable polar oligomeric or polymeric materials may include, but are not limited to, polyhydroxy-functional polyester acrylates such as BDE 1025, Bomar Specialties Co., Winsted, Connecticut, or alkoxylated acrylates such as BDE 1025, Bomar Specialties Co., Winsted, Conn. Oxidized nonylphenol acrylate (eg SR504 from Sartomer Company), ethoxylated trimethylolpropane triacrylate (eg SR9035 from Sartomer Company), or ethoxylated pentaerythritol tetraacrylate (eg SR494 from Sartomer Company).

-9-酮、4-苯甲醯基-4’-甲基二苯硫醚、與1-羥基-環己基-苯基-酮、2-羥基-2-甲基-1-苯基-丙烷-1-酮、1-[4-(2-羥基乙氧基)-苯基]-2-羥基-2-甲基-1-丙烷-1-酮、2,2-二甲氧基-1,2-二甲基乙烷-1-酮、或2-甲基-1[4-(甲硫基)苯基]-2-嗎啉基丙烷-1-酮。合適的脫模劑可包括但不限於經有機修改聚矽氧共聚物，如聚矽氧丙烯酸酯(例如得自Cytec之Ebecryl 1360或Ebecryl 350)、聚矽氧聚醚(例如得自Momentive之Silwet 7200、Silwet 7210、Silwet 7220、Silwet 7230、Silwet 7500、Silwet 7600、或Silwet 7607)。該組成物可進一步視情況包含一種或以上的以下成分：共引發劑、單官能基UV可固化成分、多官能基UV可固化成分、或安定劑。Alternatively, the polymeric material may comprise (a) at least one difunctional UV curable component, (b) at least one photoinitiator, and (c) at least one mold release agent. Suitable difunctional components can have a molecular weight greater than about 200. Difunctional acrylates are preferred, and difunctional acrylates with urethane or ethoxylated backbones are especially preferred. More specifically, suitable difunctional components may include, but are not limited to, diethylene glycol diacrylate (such as SR230 from Sartomer), triethylene glycol diacrylate (such as SR272 from Sartomer), tetraethylene glycol diacrylate (such as SR272 from Sartomer), Diol diacrylate (eg SR268 from Sartomer), polyethylene glycol diacrylate (eg SR295, SR344 or SR610 from Sartomer), polyethylene glycol dimethacrylate (eg SR603 from Sartomer) , SR644, SR252, or SR740), ethoxylated bisphenol A diacrylate (such as CD9038, SR349, SR601, or SR602 from Sartomer), ethoxylated bisphenol A dimethacrylate (such as CD540 from Sartomer) , CD542, SR101, SR150, SR348, SR480, or SR541), and urethane diacrylates (such as CN959, CN961, CN964, CN965, CN980, or CN981 from Sartomer; Ebecryl 230 from Cytec, Ebecryl 270, Ebecryl 8402, Ebecryl 8804, Ebecryl 8807, or Ebecryl 8808). Suitable photoinitiators may include, but are not limited to, diazylphosphine oxide, 2-benzyl-2-(dimethylamino)-1-[4-(4-morpholinyl)phenyl]-1-butanone , 2,4,6-trimethylbenzoyldiphenylphosphine oxide, 2-isopropyl-9H-sulfur

-9-ketone, 4-benzoyl-4'-methyldiphenylsulfide, and 1-hydroxy-cyclohexyl-phenyl-ketone, 2-hydroxy-2-methyl-1-phenyl-propane -1-one, 1-[4-(2-hydroxyethoxy)-phenyl]-2-hydroxy-2-methyl-1-propan-1-one, 2,2-dimethoxy-1 , 2-dimethylethan-1-one, or 2-methyl-1[4-(methylthio)phenyl]-2-morpholinopropan-1-one. Suitable release agents may include, but are not limited to, organomodified silicone copolymers such as silicone acrylates (eg, Ebecryl 1360 or Ebecryl 350 from Cytec), silicone polyethers (eg, Silwet® from Momentive), 7200, Silwet 7210, Silwet 7220, Silwet 7230, Silwet 7500, Silwet 7600, or Silwet 7607). The composition may further include one or more of the following components as appropriate: a co-initiator, a monofunctional UV curable component, a multifunctional UV curable component, or a stabilizer.

A preferred method of providing the polymeric material with cells is to apply a pattern of microstructures to a surface of the polymeric material, such as disclosed in US Pat. No. 6,930,818, the entire contents of which are incorporated herein by reference. Continuous sheets of polymeric material may be embossed, for example, in a roll-to-roll process using a roll having a three-dimensional pattern on its outer surface. For example, the pattern on the surface of the drum can be in the form of a plurality of micro-pillars.

The quantum dot material in the dispersion may comprise one or more granular materials having one or more particle sizes. In a preferred embodiment of the invention, the quantum dot material emits green and red light when exposed to blue light. The quantum dot material may include but not limited to CdSe core/shell luminescent nanocrystals, CdSe/ZnS, InP/ZnS, PbSe/PbS, CdSe/CdS, CdTe/CdS, or CdTe/ZnS nanocrystals.

The quantum dot material is preferably provided in the form of nanoparticles having a diameter substantially smaller than the wavelength of visible light. The term "diameter" is used herein to include the well-known "equivalent diameter" of non-spherical particles. Nanoparticles for use in the present invention need not be spherical or even essentially spherical. Variation of the properties of nanoparticle displays can be achieved using aspheric and composite particles, such as particles in which a core of one material is surrounded by a shell of a different material, and the invention extends to nanoparticles using such aspherical and/or composite particles Displays and assemblies.

The non-spherical nanoparticles used in the present invention, which are generally formed in whole or in part from a conductive material, can have a wide variety of shapes. For example, the particle may have the form of an ellipsoid, the three main axes of which may all be of different lengths, or may be a prolate or prolate spheroid of revolution. Non-spherical nanoparticles may be in the form of layers, and the term "layer" is used in its broadest sense herein to mean a body in which the largest dimension along one axis is substantially smaller than the largest dimension along each of the other two axes; thus, The layered nanoparticles may have a form similar to the plate-shaped silver halide grains well known in film. The non-spherical nanoparticles may also have the form of a truncated pyramid or a truncated cone, or a long rod. Finally, the nanoparticles can be irregular in shape. Composite (core/shell) nanoparticles for use in the present invention may have any of the forms discussed in the preceding paragraph, and generally comprise a conductive shell surrounding an insulating core, or an insulating shell surrounding a conductive core. The insulating core can be formed of, for example, silicon, titanium oxide, zinc oxide, aluminum silicate, various inorganic salts, or sulfur. As with the simple nanoparticles discussed above, the composite nanoparticles may be subject to surface modifications, such as controlling the degree to which the particles adhere to each other or to any surface they contact. A preferred type of surface modification is to attach a polymer to the nanoparticle surface.

As previously indicated, one aspect of various embodiments of the present invention is that the quantum dots retain a dispersion when encapsulated in cells. Dispersions for filling micelles as described herein may preferably (preferably in increasing order) contain less than 0.01, 0.02, 0.04, 0.06, 0.08, 0.1, 0.2, 0.3, 0.4, 0.5 weight percent quantum dots , and independently preferably (increasing preference in the order shown) not to exceed 0.6, 0.7, 0.8, 0.9, 1.0, 2.0, 3.0, 4.0, 5.0, 6.0, 7.0, 8.0, 9.0, 10 weight percent, at least for economy of quantum dots.

The solvent can be a fluid, preferably a transparent colorless liquid, and more preferably a fluid whose refractive index matches that of the light-transmitting cells and/or the sealing layer. Examples of suitable solvents include hydrocarbons such as hexane, isoalkanes (Isopar), decalin (DECALIN), 5-ethylidene-2-norbornene, fatty oils, paraffin oils, silicone fluids; aromatic Hydrocarbons, such as toluene, xylene, phenylxyleneethane, dodecylbenzene, or alkylnaphthalene; halogenated solvents, such as chloroform, perfluorodecalin, perfluorotoluene, perfluoroxylene, dichloro Benzotrifluoro, 3,4,5-trichlorobenzotrifluoro, chloropentafluorobenzene, dichlorononane, or pentachlorobenzene; and perfluorinated solvents such as FC from 3M Company, St. Paul, Minnesota -43, FC-70 or FC-5060; low molecular weight halogen-containing polymers, such as poly(perfluoropropylene oxide) from TCI America of Portland, Oregon; poly(chlorotrifluoroethylene), such as Halocarbon Oils from Halocarbon Product Corp., River Edge, NJ; perfluoropolyalkyl ethers, such as Galden from Ausimont, or the Krytox grease K-fluid series from DuPont, Delaware; from Dow -corning's polydimethylsiloxane-based silicone oil (DC-200).

The layer of sealing material used to seal the cells can be applied using a variety of techniques. For example, sealing can be accomplished by dispersing a thermoplastic or thermosetting precursor in the dispersion fluid, wherein the thermoplastic or thermosetting precursor is immiscible in the dispersion fluid and has a lower specific gravity than the display fluid. After filling the cells with the precursor/dispersion mixture, the precursor phase separates from the dispersion and forms a supernatant layer, which is then hardened or cured by solvent evaporation, interfacial reactions, moisture, heat or radiation. Specified examples of thermoplastics or thermosets and their precursors may include, for example, monofunctional acrylates, monofunctional methacrylates, polyfunctional acrylates, polyfunctional methacrylates, polyvinyl alcohol, poly Acrylic, cellulose, gelatin and other materials. Additives can be added to the sealing composition, such as polymeric binders or thickeners, photoinitiators, catalysts, curing agents, fillers, colorants, or surfactants, to improve the physical-mechanical and optical properties of the display.

唑啉)；聚(2-乙烯基吡啶)；聚(烯丙胺)；聚丙烯醯胺；聚伸乙亞胺；聚甲基丙烯醯胺；聚(苯乙烯磺酸鈉)；經四級銨基官能化之陽離子性聚合物，如聚(溴化2-甲基丙烯醯氧基乙基三甲基銨)、聚(烯丙胺鹽酸鹽)。該密封材料亦可包括水分散性聚合物分散於水中。合適的聚合物水分散液的實例可包括聚胺基甲酸酯水分散液及乳膠水分散液。適合在該水分散液中的乳膠包括聚丙烯酸酯、聚乙酸乙烯酯及其共聚物(如乙烯乙酸乙烯酯)、以及聚苯乙烯共聚物(如聚苯乙烯丁二烯與聚苯乙烯/丙烯酸酯)。In another preferred method, sealing can be accomplished by applying a sealing layer comprising an aqueous composition to the dispersion-filled cells, followed by drying. In aqueous compositions, the sealing material can be an aqueous solution of a water-soluble polymer. Examples of suitable water-soluble polymers or water-soluble polymer precursors include, but are not limited to, polyvinyl alcohol; polyethylene glycol, its copolymers with polypropylene glycol, and derivatives thereof, such as PEG-PPG-PEG, PPG- PEG, PPG-PEG-PPG; poly(vinylpyrrolidone) and its copolymers, such as poly(vinylpyrrolidone)/vinyl acetate (PVP/VA); polysaccharides, such as cellulose and its derivatives poly(glucosamine), dextran, guar gum, and starch; gelatin; melamine-formaldehyde; poly(acrylic acid), its salt forms, and copolymers thereof; poly(methacrylic acid), its salt forms, and copolymers thereof; poly(maleic acid), its salt forms, and copolymers thereof; poly(2-dimethylaminoethyl methacrylate); poly(2-ethyl-2-

oxazoline); poly(2-vinylpyridine); poly(allylamine); polyacrylamide; polyethyleneimine; polymethacrylamide; poly(sodium styrenesulfonate); Group-functionalized cationic polymers, such as poly(2-methacryloxyethyltrimethylammonium bromide), poly(allylamine hydrochloride). The sealing material may also comprise a water-dispersible polymer dispersed in water. Examples of suitable aqueous polymer dispersions may include aqueous polyurethane dispersions and aqueous latex dispersions. Latexes suitable for use in the aqueous dispersion include polyacrylates, polyvinyl acetates and their copolymers such as ethylene vinyl acetate, and polystyrene copolymers such as polystyrene butadiene and polystyrene/acrylic acid ester).

Referring again to FIG. 1 , the quantum dot film 10 may optionally include single or more preferably double release sheets 12 , 13 . The release sheets 12, 13 are preferably applied after the cells have been cured, filled, and sealed such that the sheet of polymeric material is sandwiched between two adhesive layers, one or both of which are covered by the release sheet. By providing a polymer sheet with one or more release sheets, the quantum dot film can be more easily used in the lamination method for assembling optoelectronic displays.

For example, referring now to the embodiment of FIG. 2, the optoelectronic display 20 may include a plurality of laminated layers, one of which is a quantum dot film 23, as previously described. The quantum dot film 23 may be laminated between the backlight unit 22 and the color filter 24 . The backlight unit 22 is optionally laminated to the reflective substrate 21 in order to guide light through the quantum dot film 23 . The backlight unit 22 preferably includes one or more blue LEDs, and a light guide plate designed to distribute light evenly across the display 20 .

A layer of shuttering media 26 may be laminated to the color filter 24 such that the color filter 24 is located between the quantum dot film 23 and the switching medium 26 . The switching medium may comprise any optoelectronic medium that is switchable between a substantially transparent state and an opaque state. The blue light emitted from the backlight unit 22 passes through the quantum dot film 23, which converts a part of the blue light into red and green light. Red, green and blue light enters the color filter 24 and is filtered according to the color filter segments that pass through the filter. For example, the "R" portion absorbs green and blue light and passes red light, the "G" portion absorbs red and blue light and passes green light, and the "B" portion absorbs red and green light and passes blue light. The switching media above each segment of the color filter 24 can be switched independently to combine and/or select red, green and blue light to pass through and finally be emitted by the display. Types of optoelectronic media that can be used as a switch layer include, but are not limited to, liquid crystals, electrochromic materials, and dielectrophoretic dispersions.

To control the switching medium, it is possible to provide a series of light-transmitting electrodes 25 between the layer of switching medium 26 and the color filter 24, and to apply a continuous light-transmitting front electrode 27 to the layer of switching medium 26. opposite side. The light transmissive electrode may be a thin metal layer or thin metal oxide layer such as aluminum or ITO, or may be a conductive polymer. Finally, a light transmissive protective layer 28 may be provided as the outer viewing surface of the display 20 .

As will be apparent to those skilled in the art, the particular embodiment depicted in FIG. 2 may include more or fewer layers than depicted. For example, there may be an additional layer of adhesive between the layers. Alternatively, the color filter layer 24 and a plurality of translucent electrodes 25 can be combined into one layer, so that the electrodes are made of translucent colored conductive materials. In yet another variation, the two electrode layers 25 and 27 can be reversed, so that the continuous electrode layer 27 is sandwiched between the switch layer 26 and the color filter 24, and a plurality of light-transmitting electrodes 25 are placed adjacent to the front protection layer 28 .

All contents of the above-disclosed public documents are hereby incorporated by reference.

While the invention has been described with reference to specific embodiments thereof, it should be understood by those skilled in the art that various changes may be made and equivalents may be substituted without departing from the true spirit and scope of the invention. In addition, many modifications may be made to adapt a particular situation, material, composition, method, or method step to the objective and scope of the invention. All such modifications are intended to come within the scope of the appended claims.

10: Quantum dot film 11: Translucent polymeric material 12: Release sheet 13: Release sheet 14: Translucent sealing layer 16: Solvent 18: Quantum dots 19: Quantum dots 20: Photoelectric display 21: Reflective substrate 22: Backlight unit 23: Quantum dot film 24:Color filter 25: Translucent electrode 26:Switch medium 27: Translucent front electrode 28: Translucent protective layer

The drawings illustrate one or more implementations of concepts in accordance with the present invention, which are presented by way of example only and not by way of limitation. In the drawings, the same reference numerals refer to the same or similar elements.

FIG. 1 is a side cross-sectional view of a quantum dot film according to a first embodiment of the present invention.

Figure 2 is a side cross-sectional view of a display with a quantum dot film according to an embodiment of the present invention.

1 and 2 are schematic diagrams, which are not drawn to scale for ease of understanding of various embodiments of the present invention.

10: Quantum dot film

11: Translucent polymeric material

12: Release sheet

13: Release sheet

14: Translucent sealing layer

16: Solvent

18: Quantum dots

19: Quantum dots

Claims (13)

A quantum dot thin film comprising a plurality of sealed cells formed in a layer of polymeric material and sealed by a sealing material, and the cells contain quantum dots comprising a solvent and a plurality of core/shell luminescent nanocrystals The dispersion liquid of dots, and the quantum dots of the core/shell luminescent nanocrystals are surface-modified with a polymer to increase the dispersion of the quantum dots of the core/shell luminescent nanocrystals in the solvent. The quantum dot film as claimed in claim 1, wherein the polymeric material is selected from the group consisting of thermoplastics and thermosets. The quantum dot film as claimed in item 1, wherein the sealing material is selected from the group consisting of: acrylate; polyvinyl alcohol; gelatin; polyethylene glycol; poly(vinylpyrrolidone); (maleic acid); poly(2-ethyl-2-

oxazoline); poly(allylamine); polyacrylamide; polyethyleneimine; poly(sodium styrene sulfonate); cationic polymer functionalized with quaternary ammonium groups; polyurethane aqueous dispersion liquid; and latex aqueous dispersion. The quantum dot film according to claim 3, wherein the sealing material is light-transmitting. The quantum dot thin film as claimed in item 1, wherein the solvent comprises a liquid. The quantum dot thin film according to claim 1, wherein the dispersion contains 0.01 to 10 weight percent of quantum dots. The quantum dot film as claimed in claim 1, wherein the quantum dots comprise nanocrystals selected from the group consisting of CdSe/ZnS, InP/ZnS, PbSe/PbS, CdSe/CdS, CdTe/CdS, and CdTe/ZnS. An optoelectronic display comprising the quantum dot thin film according to claim 1. Such as the optoelectronic display of claim 8, which further comprises a light-emitting layer and A color filter layer, wherein the quantum dot film is disposed between the light emitting layer and the color filter layer. The photoelectric display according to claim 9, further comprising a layer of shuttering media selected from the group consisting of liquid crystals, dielectrophoretic dispersions, and electrochromic materials. A method for manufacturing a quantum dot thin film, comprising: providing a polymeric material layer having a plurality of open cells; filling the plurality of open cells with a dispersion of quantum dots comprising a solvent and a plurality of core/shell luminescent nanocrystals , wherein the quantum dots of the core/shell luminescent nanocrystals are surface-modified with a polymer to increase the dispersion of the quantum dots of the core/shell luminescent nanocrystals in the solvent; and sealing the microcells. The method according to claim 11, wherein the step comprising embossing the plurality of open cells into the polymeric material layer is provided. The method according to claim 11, wherein the dispersion liquid further comprises a curable compound, and the sealing step comprises curing the curable compound to form a sealing layer, and the sealed cells contain the solvent and a plurality of quantum dots.

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