Zirconia and titania formulations and nanocomposites for nanoimprint lithography

Abstract

The present disclosure provides high refractive index acrylic formulations containing sub-30 nm zirconium and / or titanium oxide nanocrystals that are solvent-containing or solvent-free, have imprintable and / or inkjet printable viscosities, and can be applied by multiple deposition techniques to produce high refractive index, highly transparent nanocomposites for a variety of optical applications, including AR / VR / MR and display applications.

Description

[Technical field]

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS: This application claims priority to U.S. Provisional Application No. 63 / 166,591, filed March 26, 2021, the contents of which are incorporated by reference herein in their entirety. [Background technology]

[0002] The polymer nanocomposite formulations described herein exhibit high refractive index and high optical transmittance in the visible spectrum as well as nanoimprinting capabilities of diverse structural shapes and aspect ratios. The materials of the present disclosure are easily coated onto the surface of a desired substrate via conventional solution coating processes such as inkjet printing, spin coating, screen printing, dip, dispense, roll-to-roll, slot-die, or drawbar coating for many electronics applications. The nanocomposites of the present disclosure are prepared from formulations containing titania and / or zirconia nanocrystals and monomers or oligomers, initiators, and other additives. The nanocomposites of the present disclosure are unique in providing high refractive index and high transparency films or coatings or layers that are desirable in electronics applications such as augmented reality, mixed reality, and / or virtual reality applications where high refractive index and high transparency are critical to performance. The thickness of the coatings described herein can range from tens of nanometers to micrometers as required for a particular application.

[0003] One of the major applications of TiO2 and ZrO2 nanocomposites is in diffractive optical elements (DOEs). DOEs are very small patterns of structures used in optical devices that change the phase of light propagating through the optical structures. The range of applications and markets served by DOEs is very broad. Examples of DOEs include diffractive optical waveguides, beam splitters and diffractive diffusers for optical sensors, medical laser treatment and diagnostic devices, optical distance and speed measurement systems, fiber coupling, and laser display and lighting systems. These materials must be optically transparent and nanoimprintable to meet the industrial demands in DOE applications, and the combination of these optical and mechanical properties is important for the growing demand for DOEs with high RI.

[0004] One of the major markets impacted by DOE is Extended Reality (XR), which encompasses Augmented Reality (AR), Mixed Reality (MR), and Virtual Reality (VR). Achieving a balance between optical and mechanical properties is crucial to deliver the optically transparent and nanoimprintable materials that the industry demands. For TiO2 and ZrO2 nanocomposites for high RI applications such as AR / VR, maintaining the optical transparency and mechanical properties required for nanoimprinting is as crucial as the high RI value itself.

[0005] Nanoimprinting (NI) applications typically utilize deposition methods such as spin-coating and inkjet printing as the basis for a uniform distribution of nano-sized structures specific to the desired application. NI structures may be vertical or tilted rectangular, cylindrical or triangular lattices with specific height / width (e.g. aspect ratio) and pitch. Other more complex structures are common in nanoimprinting and are known as diffractive optical elements that contain specific three-dimensional arrays of structures of various heights and other dimensions.

[0006] Generally, nanoimprinting requires a stamp and a substrate on which a pre-cured film is deposited. The stamp may be hard or soft, but must be transparent, especially in the UV wavelength region specific to the photoinitiator absorption of the formulation. Hard stamps are traditionally made of a type of glass, and soft stamps are often made of a transparent, flexible material such as polydimethylsiloxane (PDMS). Conversely, the stamp may be opaque or translucent, provided that the substrate of the film is transparent as just described. The process continues as the stamp is placed on the pre-cured film and pressure is applied for a period of time to allow the film to flow into the stamp, allowing UV light to penetrate the transparent stamp or substrate and the stamp is released from the cured film. Other methods may incorporate thermal curing and do not require a transparent stamp. To facilitate removal of the stamp from the film / substrate, a release agent is often applied to the stamp to prevent adhesion and / or adhesive failure of the film / construct.

[0007] There are many important factors that determine whether a formulation is nanoimprintable: the viscosity of the pre-cured film (from low to no solvent), the hardness, Young's modulus and shrinkage of the cured structure. The viscosity of the pre-cured film requires a certain level of flow such that the material can be uniformly introduced through the intended area of ​​the working stamp to give the final structure. The process time, stamp dimensions and applied pressure affect the viscosity limit.

[0008] The mechanical properties of the cured structures, such as hardness and Young's modulus, are important to the extent to which the structures remain intact after the imprint process is complete. A common imprinting method uses a soft stamp that is peeled off from the cured film. There is a shear force strain to which the nanoscale structures are exposed that must be overcome. Young's modulus is a direct measure of the stiffness or resistance to distortion under the action of a given stress. Hardness, which is the resistance of the structures to deformation, needs to be high enough so that the intended shape and arrangement are not displaced or misaligned.

[0009] Shrinkage is an important nanoimprinting property that must be minimized to maintain feature dimensions at a desired level. Shrinkage is known to occur in UV-curable films due to the transition from pre-cure to final cured state, such that double bonds convert to form crosslinks. Ultimately, the change in density between the monomer and polymer increases the shrinkage rate. Traditionally, monomers with low functionality (e.g., one or two acrylates) tend to have low shrinkage rates (e.g., less than 5%), while monomers with high functionality (e.g., crosslinkers with three or more acrylates) have shown high shrinkage rates of 10% or more.

[0010] NI formulations may be solvent-borne or solvent-free. The main determining factor for which type of formulation to use is the desired film thickness and process steps. Solvent-borne formulations are usually low viscosity (5 cP or less) and may have low solids concentration (30 wt. % or less) with the goal of depositing thin films (5 microns or less). A baking step before UV curing, or sometimes after UV curing, is required to clear out the solvent. These steps are often minimized to a few minutes, as they add more time to the overall process. For environmental reasons and when the use of solvents in the baking step is undesirable, solvent-free formulations are most common. Deposition usually requires a process other than spin coating that can give the desired film thickness, such as drawbar coating.

[0011] The refractive index of the imprinted formulation is designed to match or nearly match the refractive index of the substrate. The refractive index value of the nanocomposite layer is preferably 1.60-2.10 or higher to match the refractive index of high refractive index glasses and other specialty metal oxide surfaces at visible wavelengths. Only zirconia nanocrystals can achieve values ​​within this specific range up to 1.8, since the intrinsic refractive index of bulk zirconia from 400-700 nm is 2.1-2.2. Formulations containing anatase titania nanocrystals can reach refractive index values ​​up to 2.1 or higher, since the refractive index range of bulk anatase TiO2 is 2.49-2.56. Formulations containing rutile titania nanocrystals can reach refractive index values ​​up to 2.2 or higher, since the refractive index range of bulk rutile TiO2 is 2.6-2.9. When synthesized and capped with a capping agent appropriate for dispersibility at particle sizes of 1-100 nm, preferably 4-30 nm, the refractive index values ​​of capped zirconia and titania can be 1.8-2.3 at 400-700 nm. When properly dispersed in the appropriate monomers, oligomers and polymers, capped nanocrystals at 35-90% weight loading can provide stable dispersions that can produce films with refractive index values ​​ranging from 1.6 to 2.1 or more in the visible light spectrum. Purely organic polymers and nanocomposites containing inorganic oxides with relatively low refractive indices, such as silicon dioxide and germanium oxide, can either not reach values ​​within the desired range, be composed of atomic components that can cause absorption, or require very high weight loadings to reach the final desired high refractive index value. Higher weight loadings of nanoparticles usually increase the viscosity to a very high level, precluding certain formulations for NI applications, due to the inability of the material to flow into the stamp, as previously discussed.

[0012] Nanocomposite formulations intended to index match other layers in devices such as displays (OLED, LCD, reflective, etc.), AR / VR devices, and lenses are required to be transparent unless a scattering layer is desired. The transparency of the formulations and films is strongly related to the size and distribution of the nanoparticles. By synthesizing and maintaining particle sizes below 30 nm, the formulations and films can allow high light transmission (%T>95%) across the entire visible spectrum. Particles larger than 40 nm tend to scatter light, reducing the overall transmission through the material. Agglomerated particles can also cause this scattering problem if the dispersion is not stable over time. An unstable dispersion would have particles that are not properly capped with a sufficient amount of capping agent or with a capping agent that is appropriate for the intended organic matrix. Additionally, having small particle size, narrow particle size distribution, and no agglomerates in the formulation results in a formulation with high refractive index, high transparency, and low viscosity, allowing high nanocrystal loading without a significant increase in viscosity. Summary of the Invention

[0013] The present disclosure provides nanoimprintable and / or inkjet printable solvent or solvent-free formulations with workable viscosity values, high refractive index, UV curable, and containing zirconium oxide and / or titanium dioxide nanocrystals capped in an organic matrix with a curing agent. The formulations optionally further contain the following optional ingredients: wetting agents, antioxidants, adhesion promoters, leveling agents, dispersants, plasticizers, toughening agents, thickeners, thinners, dispersants, or softeners, or organic dopants, or other functional additives. These formulations result in highly refractive, transparent nanocomposites.

[0014] The present disclosure provides the following non-limiting numbered embodiments as further illustrations of the disclosed technology. 1. A formulation comprising a dispersion of at least partially capped nanocrystals and a matrix comprising at least one solvent, monomer, oligomer, polymer or crosslinker, and optionally a curing agent, surfactant, wetting agent, antioxidant, adhesion promoter, leveling agent, dispersant, plasticizer, toughening agent, thickener, thinner, dispersing agent or softener, or organic dopant or other functional additive, wherein the nanocrystals typically comprise a metal oxide selected from zirconium oxide, titanium oxide, hafnium oxide, zinc oxide, tantalum oxide, niobium oxide, and combinations thereof.

[0015] 2. The formulation of embodiment 1, wherein the matrix comprises one or more acrylate and / or methacrylate monomers, a reactive diluent, a curing agent, and, optionally, at least one surfactant or wetting agent.

[0016] 3. The formulation of embodiment 1 or 2, wherein the average particle size of the at least partially capped nanocrystals, as measured by DLS or TEM, is within the range of 1-30 nm (e.g., 5 nm, 10 nm, 15 nm, 20 nm, 30 nm, or any range or value between the cited values, such as 5-30 nm or 5-20 nm, etc.).

[0017] 4. The above nanocrystals are methyltrimethoxysilane, n-propyltrimethoxysilane, n-propyltriethoxysilane, n-octyltrimethoxysilane, n-octyltriethoxysilane, phenyltrimethoxysilane, dodecyltrimethoxysilane, m,p-Ethylphenethyltrimethoxysilane, 2-[methoxy(polyethyleneoxy)propyl]trimethoxysilane, methoxy(triethyleneoxy)propyltrimethoxysilane, 3-aminopropyltrimethoxysilane, 3-mercaptopropyltrimethoxysilane, 3-(methacryloyloxy)propyltrimethoxysilane, 3-(acryloyloxy)propyltrimethoxysilane, 3-isocyanatepropyltriethoxysilane, 3-isocyanatepropyltrimethoxysilane, 3-glycidoxypropyltrimethoxysilane, vinyltrimethoxysilane, allyltrimethoxysilane, 1-hexynyltrimethoxysilane, 1-octenyltrimethoxysilane, (phenylaminomethyl)methyldimethoxysilane, N-phenylaminopropyltrimethoxysilane, 3-(4-pyridylethyl)thiopropyltrimethoxysilane, N-(3-trimethoxysilylpropyl)pyrrole, 2-(3-trimethoxysilylpropylthio)thiophene, (3-trimethoxysilylpropyl (2-diphenylphosphino)ethyl dimethylethoxysilane, 2-(diphenylphosphino)ethyl triethoxysilane, 3-(diphenylphosphino)propyl triethoxysilane, heptanol, hexanol, octanol, benzyl alcohol, phenols, ethanol, propanol, butanol, oleyl alcohol, dodecyl alcohol, octadecanol, triethylene glycol monomethyl ether terephthalic acid, octanoic acid, acetic acid, propionic acid, 2-[2-(2-methoxyethoxy)ethoxy]acetic acid, oleic acid, benzoic acid, stearic acid, trifluoroacetic acid, biphenyl-4-carboxylic acid, 2-(2-methoxyethoxy)acetic acid, methacrylic acid, mono-2-(methacryloyloxy)ethylsuccinic acid, 2-mercaptoethanol, 2-{2-[2-(2-mercaptoethoxy)ethoxy)ethoxy]ethoxy}ethanol, 2-(2-methoxyethoxy)ethanethiol, 1-octanethiol, 2,4. The formulation of any one of embodiments 1-3, at least partially capped with at least one capping agent selected from sodium 3-dimercaptopropane sulfate monohydrate, sodium dodecyl sulfate, dodecylphosphonic acid, octylphosphonic acid, (11-mercaptoundecyl)phosphonic acid, (11-(acryloyloxy)undecyl)phosphonic acid, 11-methacryloyloxyundecylphosphonic acid, [2-[2-(2-methoxyethoxy)ethoxy]ethyl]phosphonic acid ethyl ester, and combinations thereof.

[0018] 5. The formulation according to any one of embodiments 1-4 includes a weight loading of zirconium oxide and / or titanium dioxide nanocrystals ranging from 5-95% by weight of the formulation. 6. The formulation of any one of the preceding embodiments, wherein the zirconium oxide and / or titanium dioxide nanocrystals are at least partially capped and the formulation further comprises a monofunctional acrylate and / or methacrylate monomer having a high refractive index at 589 nm, preferably >1.50 RI. Examples may include benzyl (meth)acrylate (BA and BMA), ethylene glycol phenyl ether (meth)acrylate (PEA and PEMA), 2-phenoxybenzyl acrylate (PBA), biphenyl methacrylate (BPMA), 2-phenylphenol methacrylate (PPMA), 2-phenylethyl acrylate (2-PEA), 2-(phenylthio)ethyl acrylate (PTEA), or combinations thereof.

[0019] 7. The zirconium oxide and / or titanium dioxide nanocrystals are at least partially capped and the formulation is selected from the group consisting of 1,6-hexanediol di(meth)acrylate (HDDA and HDDMA), di(ethylene glycol) di(meth)acrylate (DEGDA and DEGDMA), ethylene glycol diacrylate, glycerol 1,3-diglycerolate diacrylate, tri(propylene glycol) diacrylate, trimethylolpropane tri(meth)acrylate (TMPTA and TMPTMA), trimethylolpropane ethoxylate ... The formulation of any one of the preceding embodiments, further comprising di-, tri-, tetra- and penta-functional acrylate and / or methacrylate monomers, such as 1,6-hexanediol ethoxylate diacrylate (EOTMPTA and EOTMPTMA), 1,6-hexanediol ethoxylate diacrylate, pentaerythritol tetraacrylate (PETA), bis(methacryloylthiophenyl)sulfide (BMTPS), tris(2-hydroxyethyl)isocyanurate triacrylate (THEICTA), and dipentaerythritol penta- / hexa-acrylate (DPHA).

[0020] 8. The formulation according to any one of the first to seventh embodiments, wherein the zirconium oxide and / or titanium dioxide nanocrystals are at least partially capped, and the formulation further comprises a reactive diluent, such as 1-vinyl-2-pyrrolidone (NVP), N-vinylcaprolactam, 2-(2-vinyloxyethoxy)ethyl (meth)acrylate, isobutyl acrylate, styrene (STY), 4-methylstyrene (4MS), 4-vinylanisole (4VA) and divinylbenzene (DVB). For example, 1-vinyl-2-pyrrolidone is added to the formulation according to any one of the first to eighth embodiments to improve surface cure or adhesion. The weight percentage of the reactive diluent is 10-80% by weight based on the total monomer content. The preferred weight percentage of the reactive diluent is 25-70% by weight based on the total monomer content.

[0021] 9. The formulation of any one of the preceding embodiments, wherein the zirconium oxide and / or titanium dioxide nanocrystals are at least partially capped, and the formulation further comprises a di-, tri-, or tetra-functional thiol crosslinker, such as trimethylolpropane tris(3-mercaptopropionate). The weight percentage of the crosslinker is 1-80% by weight based on the total monomer content. The preferred weight percentage of the crosslinker is 1-50% by weight based on the total monomer content.

[0022] 10. The formulation according to embodiment 9 comprises one or more high refractive index and / or sulfur-containing monomers and / or resins, preferably said monomers and / or resins are compounds having the following structure and their derivatives:

[0023] [ka]

[0024] [ka]

[0025] is selected from. 11. The formulation of any one of the preceding embodiments, wherein the zirconium oxide and / or titanium dioxide nanocrystals are at least partially capped and the formulation further comprises a reactive organic dopant, such as phenanthrene (PhA) or 9-vinylcarbazole (NVCb). The concentration of the organic dopant may range from 1 to 50% by weight.

[0026] 12. The formulation of any one of the preceding embodiments, wherein the zirconium oxide and / or titanium dioxide nanocrystals are at least partially capped, and the formulation further comprises a surfactant or combination of surfactants that are either non-reactive or reactive in acrylate monomer systems, such as polyether modified siloxanes, fluorosurfactants, etc. The concentration of the surfactant in the total formulation is in the range of 0.1-2.0 wt.%. The preferred concentration of the surfactant is in the range of 0.5-1.0 wt.%.

[0027] 13. The formulation according to any one of the preceding embodiments, wherein the zirconium oxide and / or titanium dioxide nanocrystals are at least partially capped, and the formulation optionally further comprises scattering particles such as titanium dioxide, aluminum oxide, silicon dioxide, and low index and / or high index polymer particles. The particle size of the scatterers may range from 100 to 400 nm. The concentration of the scatterers in the total formulation may range from 0.1 to 30.0 wt.%. The preferred concentration of the scatterers may range from 0.5 to 17.0 wt.%.

[0028] 14. The formulation according to any one of the preceding embodiments, further comprising a curing agent or photoinitiator, such as Irgacure 184, Irgacure 819, ITX, TPO, Ebercryl P39, Esacure 1001M, and a synergist, such as Ebercryl P115 and CN374, or a HALS-based initiator. The concentration of the photoinitiator in the total formulation is in the range of 0.1-20% by weight based on the monomer content. The preferred concentration of the photoinitiator is in the range of 1.0-4.0% by weight based on the monomer content.

[0029] 15. The formulation of any one of the preceding embodiments, wherein the formulation is solvent-free, i.e., 5% by weight or less of solvent is present. 16. The formulation of any one of the preceding embodiments, wherein the formulation contains a solvent in an amount greater than 10% by weight of the total formulation.

[0030] 17. The solventless and / or solvent-containing formulation according to any one of embodiments 15 and 16 and embodiments 34-51, wherein the viscosity of the formulation is in the range of 3 to 50,000 cP when measured at 25° C. using a Brookfield RVDV II+ cone and plate viscometer. A preferred viscosity for inkjet printing at 25° C. is 5 to 20 cP. If cartridge heating is applicable, the viscosity at 25° C. may be 15 to 100 cP at a cartridge temperature between 35 to 100° C. Alternatively, the viscosity of the formulation when measured at 25° C. is 5 cP to 10 cP, or 10 cP to 15 cP, 15 cP to 20 cP, 20 cP to 30 cP, 30 cP to 50 cP, or 50 cP to 100 cP. For deposition methods other than inkjet printing, the viscosity can range from 100 cP to 1,000 cP, 1,000 cP to 5,000 cP, 5,000 cP to 10,000 cP, or 10,000 to 50,000 cP.

[0031] 18. The solvent-free and / or solvent-containing formulation according to any one of embodiments 15-17, wherein the nanocrystal loading is 5-10%, 10-15%, 15-20%, 20-25%, 25-30%, 30-35%, 35-40%, 40-45%, 45-50%, 50-55%, 55-60%, 60-65%, 65-70%, 70-75%, 75-80%, 85-90%, 90-95% by weight of the formulation.

[0032] 19. The refractive index at 589 nm, 520 nm and / or 450 nm is 1.52 to 1.56, 1.56 to 1.58, 1.58 to 1.60, 1.60 to 1.62, or 1.62 to 1.64, 1.64 to 1.66, or 1.66 to 1.68, or 1.68 to 1.70, or 1.70 to 1.72, or 1.72 to 1.74, or 1.74 to 1.76, or 1.76 to 1.78, or 1.78 to 1.80, or 1.80 to 1.82, or 1.82 to 1.84, or is 1.84 to 1.86, or 1.86 to 1.88, or 1.88 to 1.90, or 1.90 to 1.92, or 1.92 to 1.94, or 1.94 to 1.96, or 1.96 to 1.98, or 1.98 to 2.00, or 2.0 to 2.02, or 2.02 to 2.04, or 2.04 to 2.06, or 2.06 to 2.08, or 2.08 to 2.10.

[0033] 20. The solvent-free and / or solvent-containing formulation of any one of embodiments 15-17 and embodiments 34-51, wherein the %T of the formulation in UV-A, near-UV, visible, near-IR, and / or infrared wavelengths is between 99% and 95%, or between 95% and 90%, or between 90% and 85%, or between 85% and 80%, or between 80% and 75%, or between 75% and 70%, or between 70% and 65%, or between 65% and 60%, or between 60% and 55%, or between 55% and 50%, or between 50% and 45%, or between 45% and 40%, or between 40% and 35%, or between 35% and 30%, or between 30% and 25%, or between 25% and 20%, or between 20% and 15%, or between 15% and 10%.

[0034] 21. The formulation according to any one of embodiments 1 to 20 and embodiments 34 to 51, which can be deposited into a film via a process selected from spin coating, slot die coating, screen printing, inkjet printing, dip coating, draw bar coating, roll-to-roll printing, spray coating, dispensing, volume casting, screen printing and any combination thereof.

[0035] 22. The formulation of any one of embodiments 1-21 and 34-51, deposited on an optically transparent hydrophilic substrate, such as fused silica, soda lime, borosilicate glass, aluminum silicate, silicon nitride, indium tin oxide substrates, etc. Conversely, the formulation is deposited on an optically transparent hydrophobic substrate, such as polyethylene terephthalate, polyimide, acrylic polymers, cyclic olefin copolymers, polycarbonate, polystyrene, and silicone.

[0036] 23. The formulation according to any one of embodiments 1 to 22 and embodiments 34 to 51, wherein the formulation is capable of producing nanoimprinted structures (i.e., height, width, and pitch) on the order of 10 to 1000 nm.

[0037] 24. The formulation according to any one of embodiments 1 to 22 and embodiments 34 to 51, wherein the formulation is capable of producing nanoimprinted structures having an aspect ratio of 0.5:1 to 10:1.

[0038] 25. A nanocomposite comprising a cured or partially cured formulation according to any one of embodiments 1-24 and 34-51, wherein the formulation is cured via UV irradiation under a UV LED source having a wavelength of 365, 385, 395 and / or 405 nm, or using a mercury "D", "H" and / or "V" lamp. The UV dose is 0.1-10 J / cm. 2 The preferred UV dose is 0.5-2 J / cm 2 UV curing can occur in air or under inert conditions, particularly a nitrogen atmosphere.

[0039] 26. The nanocomposite film of embodiment 25, wherein the film thickness ranges from 50 nanometers to 100 micrometers. Preferred film thickness values ​​can range from 50 nanometers to 20 micrometers.

[0040] 27. The nanocomposite film according to any one of embodiments 25 and 26, characterized in that the surface roughness of the film at least at 1 μm is 5 to 4 nm, or 4 to 3 nm, or 3 to 2 nm, or 2 to 1 nm, or 1 to 0.5 nm, or 0.5 to 0.1 nm.

[0041] 28. The nanocomposite of any one of embodiments 25-27, wherein the %T of the cured nanocomposite at a thickness of less than 10 microns in UV-A, near-UV, visible, near-IR, and / or infrared wavelengths is 99%-95%, or 95%-90%, or 90%-85%, or 85%-80%, or 80%-75%, or 75%-70%, or 70%-65%, or 65%-60%, or 60%-55%, or 55%-50%, or 50%-45%, or 45%-40%, or 40%-35%, or 35%-30%, or 30%-25%, or 25%-20%, or 20%-15%, or 15%-10%.

[0042] 29. The nanocomposite of any one of embodiments 25-27, wherein the %T of the cured nanocomposite at a thickness of less than 1 micron in UV-A, near UV, visible, near infrared, and / or infrared wavelengths is 99%-95%, or 95%-90%, or 90%-85%, or 85%-80%, or 80%-75%, or 75%-70%, or 70%-65%, or 65%-60%, or 60%-55%, or 55%-50%, or 50%-45%, or 45%-40%, or 40%-35%, or 35%-30%, or 30%-25%, or 25%-20%, or 20%-15%, or 15%-10%.

[0043] 30. The nanocomposite of any one of embodiments 25-27, wherein the %T of the cured nanocomposite at a thickness of 10-30 microns in the UV-A, near UV, visible, near infrared, and / or infrared wavelengths is 99%-95%, or 95%-90%, or 90%-85%, or 85%-80%, or 80%-75%, or 75%-70%, or 70%-65%, or 65%-60%, or 60%-55%, or 55%-50%, or 50%-45%, or 45%-40%, or 40%-35%, or 35%-30%, or 30%-25%, or 25%-20%, or 20%-15%, or 15%-10%.

[0044] 31. The refractive index of the cured nanocomposite at 589 nm, 520 nm and / or 450 nm is 1.54-1.56, 1.56-1.58, 1.58-1.60, 1.60-1.62, or 1.62-1.64, 1.64-1.66, or 1.66-1.68, or 1.68-1.70, or 1.70-1.72, or 1.72-1.74, or 1.74-1.76, or 1.76-1.78, or 1.78-1.80, or 1.80-1.82; 31. The nanocomposite of any one of embodiments 25-30, wherein the MnO2 is from 1.82 to 1.84, or from 1.84 to 1.86, or from 1.86 to 1.88, or from 1.88 to 1.90, or from 1.90 to 1.92, or from 1.92 to 1.94, or from 1.94 to 1.96, or from 1.96 to 1.98, or from 1.98 to 2.00, or from 2.0 to 2.02, or from 2.02 to 2.04, or from 2.04 to 2.06, or from 2.06 to 2.08, or from 2.08 to 2.10.

[0045] 32. The nanocomposite of any one of embodiments 25-31, wherein the hardness of the cured nanocomposite, measured using nanoindentation, is 1-5 MPa, or 5-20 MPa, or 20-50 MPa, or 50-100 MPa, or 100-150 MPa, or 150-200 MPa, or 200-250 MPa, 250-300 MPa, or 300-350 MPa, or 350-400 MPa.

[0046] 33. The modulus of the cured nanocomposite, measured using nanoindentation, is 0.1-0.5 GPa, or 0.5-1.0 GPa, or 1.0-1.5 GPa, or 1.5-2.0 GPa, or 2.0-2.5 GPa, or 2.5-3.0 GPa, or 3.0-3.5 GPa, or 3.5-4.0 GPa, or 4.0-4.5 GPa, or 4.5-5.0 GPa, 33. The nanocomposite of any one of embodiments 25-32, wherein the compressive strength is 5.0-5.5 GPa, or 5.5-6.0 GPa, or 6.0-6.5 GPa, or 6.5-7.0 GPa, or 7.0-7.5 GPa, or 7.5-8.0 GPa, or 8.0-8.5 GPa, or 8.5-9.0 GPa, or 9.0-9.5 GPa, or 9.5-10.0 GPa.

[0047] 34. A formulation comprising metal oxide nanocrystals (any as described in this disclosure) at least partially capped in a matrix, wherein the matrix comprises (i) at least one monomer, oligomer, or polymer, such as any as described in this disclosure (e.g., BPMA, PTEA, PBA, 2-PEA, BAC, HDDA, NVP, etc.); (ii) any crosslinker, such as any as described in this disclosure (e.g., BMTPS, THEICTA, TMPTA, HR6042, etc.); (iii) a polymerization initiator, such as a curing agent or photoinitiator, such as any as described in this disclosure (e.g., TPO, I819, ITX, etc.); and optionally (iv) a solvent, such as PGMEA.

[0048] 35. The formulation of embodiment 34, wherein the at least partially capped metal oxide nanocrystals are at least partially capped ZrO2, and preferably the average particle size of the at least partially capped ZrO2 nanocrystals, as measured by DLS or TEM, is within the range of 1 to 30 nm (e.g., 5 nm, 10 nm, 15 nm, 20 nm, 30 nm, or any range or value between the cited values, such as 5 to 30 nm or 5 to 20 nm, etc.).

[0049] 36. The formulation of embodiment 35, comprising a solvent in an amount of 40 to 60% by weight of the formulation. 37. The formulation of embodiment 36, comprising, based on the weight of the formulation, 25-40 wt % (e.g., 30-40%) of at least partially capped metal oxide nanocrystals, 3-15 wt % (e.g., 5-10%) of at least one monomer, oligomer, or polymer, 1-15 wt % (e.g., 2-10%) of a crosslinker, and 0.1-2 wt % (e.g., 0.1-1%, e.g., 0.5-1%) of a curing agent or polymerization initiator.

[0050] 38. The formulation of embodiment 35, which is solvent-free, i.e., the solvent is present in an amount of 5% by weight or less of the formulation. 39. The formulation of embodiment 38, comprising, based on the weight of the formulation, 60-80 wt % (e.g., 64-70%) of at least partially capped metal oxide nanocrystals, 10-30 wt % (e.g., 15-27%) of at least one monomer, oligomer, or polymer, 5-20 wt % (e.g., 8-14%) of a crosslinker, and 0.1-2 wt % (e.g., 0.5-1.5%, e.g., 1%) of a curing agent or polymerization initiator.

[0051] 40. The formulation of embodiment 38, comprising, based on the weight of the formulation, 20-60% by weight (e.g., 35-45%) of at least partially capped metal oxide nanocrystals, 30-70% by weight (e.g., 40-60% or 46-56%) of at least one monomer, oligomer, or polymer, 0-20% by weight (e.g., 0-10%, 5-15%, etc.) of a crosslinker, and 0.1-5% by weight (e.g., 1-3%) of a curing agent or polymerization initiator.

[0052] 41. The formulation of embodiment 40, further comprising a synergist (e.g., any of those described in this disclosure), such as CN374, in an amount of 0.1-10%, such as 1-5% or 3% by weight of the formulation.

[0053] 42. The formulation of embodiment 40 or 41, further comprising a surfactant, such as a BYK surfactant (e.g., any of those described in this disclosure), in an amount of 0.1 to 10%, such as 0.5 to 2% by weight of the formulation.

[0054] 43. The formulation of embodiment 34, wherein the at least partially capped metal oxide nanocrystals are at least partially capped TiO2, and preferably the average particle size of the at least partially capped TiO2 nanocrystals, as measured by DLS or TEM, is within the range of 1 to 30 nm (e.g., 5 nm, 10 nm, 15 nm, 20 nm, 30 nm, or any range or value between the cited values, such as 5 to 30 nm or 5 to 20 nm, etc.).

[0055] 44. The formulation of embodiment 43, comprising a solvent in an amount of 10 to 85% by weight of the formulation. 45. The formulation of embodiment 44, comprising, based on the weight of the formulation, 10-80% by weight (e.g., 10%, 30%, 40%, 50%, 60%, 70%, 75%, or any range or value between the cited values, e.g., 30-50%, 20-60%, etc.) of at least one monomer, oligomer, or polymer, 3-20% by weight (e.g., 5-10%, 4-15%, etc.) of at least one monomer, oligomer, or polymer, 0.5-15% by weight (e.g., 1-5%, 5-10%, 2-10%, etc.) of a crosslinker, and 0.1-2% by weight (e.g., 0.1-1%, e.g., 0.5-1%) of a curing agent or polymerization initiator.

[0056] 46. ​​The formulation of embodiment 43, which is solvent-free, i.e., the solvent is present in an amount of 5% by weight or less of the formulation. 47. The formulation of embodiment 46, comprising, based on the weight of the formulation, 60-80% by weight (e.g., 60-74%) of at least partially capped metal oxide nanocrystals, 10-40% by weight (e.g., 15-30%) of at least one monomer, oligomer, or polymer, 5-20% by weight (e.g., 8-12%) of a crosslinker, and 0.1-2% by weight (e.g., 0.5-1.5%, e.g., 1%) of a curing agent or polymerization initiator.

[0057] 48. The formulation of embodiment 46, comprising, based on the weight of the formulation, 20-60% by weight (e.g., 40-50%) of at least partially capped metal oxide nanocrystals, 30-70% by weight (e.g., 40-60% or 46-56%) of at least one monomer, oligomer, or polymer, 0-20% by weight (e.g., 0-10%, 4%, 5-15%, etc.) of a crosslinker, and 0.1-5% by weight (e.g., 3%, 1-3%, etc.) of a curing agent or polymerization initiator.

[0058] 49. The formulation of embodiment 48, further comprising a surfactant such as a BYK surfactant (e.g., any described in this disclosure) in an amount of 0.1 to 10%, for example 0.5 to 2% by weight of the formulation.

[0059] 50. The formulation according to any one of embodiments 34 to 49, which is capable of nanoimprinting. 51. The formulation of any one of embodiments 34 to 49, which is inkjet printable.

[0060] 52. A nanocomposite prepared from the formulation described in any one of embodiments 34 to 51. 53. Formulations according to any of the preceding Examples 1-6 of the present application, including formulations A1, A2, A3, A4, A5, B1, B2, C1, C2, C3, C4, C5, C6, C7, C8, C9, C10, C11, C12, C13, C14, C15, C16, C17, C18, C19, C20, C21, D1, D2, D3, D4, E1, E2, E3, E4, E5, F1, and F2.

[0061] 54. A nanocomposite prepared from any of the formulations described herein, such as those described in Examples 1-6 of the present application. 55. Any of the formulations and nanocomposites described herein in claims 1-46 as filed.

[0062] 56. A device comprising any of the nanocomposites described herein. It is to be understood that both the foregoing summary and the following detailed description are exemplary and explanatory only and are not restrictive of the invention herein. [Brief description of the drawings]

[0063] [Figure 1] Core particle size of TiO2 nanocrystals by TEM for (a) 5 nm core TiO2, (c) 15 nm core TiO2, and (e) 5 nm core ZrO2, respectively, and dynamic light scattering (DLS) particle size distribution curves of these nanocrystals dispersed in PGMEA in (b), (d), and (f). [Diagram 2] Images showing the NIL functionality of formulations A1 (right) and A2 (left). [Diagram 3] Images showing the NIL features of formulations B1 (a) and B2 (c) and a table showing the structural fidelity to the master of formulation B1 NIL patterns (b). [Figure 4] Images showing the NIL functionality of formulations C1 (top and bottom left), C2 (bottom middle) and C3 (bottom right). [Diagram 5] Images showing the NIL features of formulations D1 and D2: (a) triangular structures, D1 on top and D2 on bottom; (b) pillars, D1 on top and D2 on bottom. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0064] Characterization The formulations and nanocomposites of the present disclosure may be analyzed according to methods known to those of skill in the art, and exemplary analyses are provided herein, including those provided in the Examples section herein.

[0065] Formulations of the present disclosure are analyzed using a TA instrument Q500 thermogravimetric analyzer (TGA) to measure inorganic solids concentration. TGA is performed on nanocrystal dispersions in solvents with boiling points <200C to measure the organic content of the capped nanocrystals. The percent mass at 200C relative to the initial mass is considered the capped nanocrystal, and the percent mass at 700C relative to the initial mass is considered the inorganic portion of the capped nanocrystal, i.e., the inorganic solids concentration. The percent organic (%Org) of the capped nanocrystal is defined as the difference between the percent mass at 200C (M200C) and 700C (M700C) divided by the percent mass at 200C.

[0066]

number

[0067] For nanocomposites or blends, the percent solids (%S) is calculated from the inorganic content of the nanocomposite and the organic content of the capped nanocrystals measured in the solvent.

[0068]

number

[0069] The capped nanocrystals of the formulation of the present disclosure comprise less than 10% by weight of the total formulation, or between 10% and 20% by weight of the total formulation, or between 20% and 30% by weight of the total formulation, or between 30% and 40% by weight of the total formulation, or between 40% and 50% by weight of the total formulation, or between 50% and 60% by weight of the total formulation, or between 60% and 70% by weight of the total formulation, or between 70% and 80% by weight of the total formulation, or between 80% and 90% by weight of the total formulation, or between 90% and 93% by weight of the total formulation.

[0070] The capped nanocrystals of the nanocomposite of the present disclosure comprise less than 10 wt% of the total nanocomposite, or between 10% and 20 wt% of the total nanocomposite, or between 20% and 30 wt% of the total nanocomposite, or between 30% and 40 wt% of the total nanocomposite, or between 40% and 50 wt% of the total nanocomposite, or between 50% and 60 wt% of the total nanocomposite, or between 60% and 70 wt% of the total nanocomposite, or between 70% and 80 wt% of the total nanocomposite, or between 80% and 90 wt% of the total nanocomposite, or between 90% and 93 wt% of the total nanocomposite.

[0071] Optical transmittance is a common technique for evaluating the quality of dispersions, formulations, and nanocomposite films or coatings. Light propagating through a sample can be absorbed, scattered, or transmitted. Standard transmittance at a given wavelength is defined as Tn=I / I0, where I0 is the intensity of the incident light, and I is the intensity of the forward light collected by the detector, including both the light transmitted unscattered and the light scattered in the forward direction. In theory, the forward direction is defined as the same direction as the incident light, however, the detector usually collects light within a small solid angle around this direction due to the size limitations of the detector. This transmittance is referred to as standard transmittance or simply transmittance throughout this disclosure. The absorbance of a sample at a given wavelength, i.e., optical density (OD), is defined as follows:

[0072]

number

[0073] When measuring standard transmittance, measurement artifacts such as Fresnel reflections from various interfaces and absorption by the cuvette walls must be considered and eliminated. This can be handled either by using a reference and measuring the sample and reference side-by-side in the instrument, or by measuring the sample and reference in sequence and then mathematically correcting the data afterwards. Liquid nanocrystal dispersion samples can be measured in cuvettes made of glass, quartz, or plastic, and due to the limited thickness of the cuvette walls, there are four interfaces where Fresnel reflections can occur and two walls where absorption can occur. Using a cuvette with the same material, wall thickness, and path length as a reference will give results with sufficient accuracy.

[0074] For thin film nanocomposites, to correct for absorption and reflection at the interface, the coated substrate is measured either side-by-side or in sequence against a blank substrate made of the same material with the same thickness and surface smoothness. Because the coating has a different refractive index than the substrate and air, the reflection from the front side of the film and the substrate may be slightly different, often resulting in a transmission greater than 100% based on the algorithm used by the spectrophotometer. The above effects can be corrected, but the process is complicated and the error is usually small. For convenience, the transmission data presented in this disclosure is measured without correction.

[0075] Light that is not transmitted, scattered, or reflected is absorbed. Absorbance can be calculated by subtracting transmitted, scattered, and reflected light from the incident light. The optical transmittance at 450 nm of the formulations of the present disclosure without the curing agent, as measured in a 1 cm path length cuvette using a Perkin Elmer Lambda 850 spectrophotometer, is 99%-95%, or 95%-90%, or 90%-85%, or 85%-80%, or 80%-75%, or 75%-70%, or 70%-65%, or 65%-60%, or 60%-55%, or 55%-50%, or 50%-45%, or 45%-40%, or 40%-35%, or 35%-30%, or 30%-25%, or 25%-20%, or 20%-15%, or 15%-10%.

[0076] The optical transmittance at 400 nm of the formulations of the present disclosure without the curing agent, as measured in a 1 cm path length cuvette using a Perkin Elmer Lambda 850 spectrophotometer, is 99%-95%, or 95%-90%, or 90%-85%, or 85%-80%, or 80%-75%, or 75%-70%, or 70%-65%, or 65%-60%, or 60%-55%, or 55%-50%, or 50%-45%, or 45%-40%, or 40%-35%, or 35%-30%, or 30%-25%, or 25%-20%, or 20%-15%, or 15%-10%.

[0077] The optical transmittance at 450 nm of the nanocomposites of the present disclosure when measured as a 1 um (micrometer) thick film on a transparent substrate using a Perkin Elmer Lambda 850 spectrophotometer is 99%-95%, or 95%-90%, or 90%-85%, or 85%-80%, or 80%-75%, or 75%-70%, or 70%-65%, or 65%-60%, or 60%-55%, or 55%-50%, or 50%-45%, or 45%-40%, or 40%-35%, or 35%-30%, or 30%-25%, or 25%-20%, or 20%-15%, or 15%-10%.

[0078] The optical transmittance at 400 nm of the nanocomposites of the present disclosure when measured as a 1 um (micrometer) thick film on a transparent substrate using a Perkin Elmer Lambda 850 spectrophotometer is 99%-95%, or 95%-90%, or 90%-85%, or 85%-80%, or 80%-75%, or 75%-70%, or 70%-65%, or 65%-60%, or 60%-55%, or 55%-50%, or 50%-45%, or 45%-40%, or 40%-35%, or 35%-30%, or 30%-25%, or 25%-20%, or 20%-15%, or 15%-10%.

[0079] The viscosity of the formulations of the present disclosure is about 1 cP to 100,000, 100 cP to 100,000 cP, or 1 cP to about 12,000 cP. The viscosity of the formulations of the present disclosure, as measured at 25 C using a Brookfield RVDV II+ cone and plate viscometer, is about 1 cP, about 2 cP, about 5 cP, about 10 cP, about 15 cP, about 20 cP, about 25 cP, about 30 cP, about 40 cP, about 50 cP, about 60 cP, about 75 cP, about 100 cP, about 200 cP, 500 cP, or about 1,000 cP, or about 1,500 cP, or about 2,000 cP, or about 2,500 cP, or about 3,000 cP, or about 3,500 cP, or about 4,000 cP, or about 4,500 cP, or about 5,500 cP, or about 6,000 cP, or about 6,500 cP, or about 7,000 cP, or about 7,500 cP, or about 8,000 cP, or about 8,500 cP, or about 9,000 cP, or about 9,500 cP, or about 10,000 cP, 11,000 cP, 12,000 cP.

[0080] Formulation ingredients and properties The present disclosure provides solvent-containing and / or solvent-free nanoimprintable, highly transparent, high RI formulations comprising at least partially capped zirconium oxide and / or titanium dioxide nanocrystals dispersed in monomers, oligomers, polymers or mixtures thereof. The formulations optionally include curing agents, adhesion promoters, wetting agents, leveling agents, dispersants, viscosity modifiers, organic dopants and antioxidants. These formulations allow for the production of nanocomposites and thin film coatings with high refractive index and high optical transparency. These formulations, while specific to inkjet printing applications, should have strong resistance to wetting of the inkjet nozzle faceplate and adequate wetting to the desired substrate. Liquids wet certain solid surfaces and form a contact angle once the liquid reaches equilibrium. Very low values ​​of the contact angle are typically less than 10°, and the liquid has high wetting with the surface. High wetting allows for uniform coating to be achieved. Contact angles greater than 45° indicate partial or no wetting. In such cases, an irregular surface and possible lenticular printing is a likely outcome and is often an indication of a high surface tension liquid on a low surface energy surface.

[0081] The resulting nanocomposite films should have moderate to high cure properties, good adhesion to the intended substrate, and good film uniformity. The capped zirconia and titania nanocrystals of the present disclosure have a narrow particle size distribution with an average diameter range of 1-100 nm, or 3-30 nm, preferably 4-20 nm, as measured by transmission electron microscopy (TEM).

[0082] The capped zirconia and titania nanocrystals of the present disclosure are monodispersed with an average diameter of less than 100 nm, preferably <60 nm, as measured using a Malvern Zetasizer Nano S Dynamic Light Scattering (DLS) instrument when dispersed in a solvent such as PGMEA at a concentration of 5 wt% or less. DLS measures the particle size along with the solvent shell surrounding the nanocrystal. The capped nanocrystals of the present disclosure remain dispersible or non-agglomerated in the polymer or monomer matrix. Such physical characteristics of the materials of the present disclosure not only reduce light scattering but also improve processability.

[0083] The capped nanocrystals of the present disclosure are prepared by the methods described in Patent Nos. US8592511B2, and PCT / US2019 / 062439 (published as WO2020 / 106860A1), the entire contents of each of which are incorporated herein by reference.

[0084] The nanocrystals of the present disclosure are at least partially capped with specific functional groups, also called capping agents or capping groups. These specific functional groups are grafted onto the surface of the nanocrystals. The capping reaction can be carried out in the presence of water. As used herein, capped nanocrystals and at least partially capped nanocrystals are functionally equivalent.

[0085] The capping agent of the capped nanocrystals in the formulation of the present disclosure includes organic silanes, organic carboxylic acids and / or organic alcohols. Examples of the capping agent include methyltrimethoxysilane, n-propyltrimethoxysilane, n-propyltriethoxysilane, n-octyltrimethoxysilane, n-octyltriethoxysilane, phenyltrimethoxysilane, dodecyltrimethoxysilane, m,p-Ethylphenethyltrimethoxysilane, 2-[methoxy(polyethyleneoxy)propyl]trimethoxysilane, methoxy(triethyleneoxy)propyltrimethoxysilane, 3-aminopropyltrimethoxysilane, 3-mercaptopropyltrimethoxysilane, 3-(methacryloyloxy)propyltrimethoxysilane, 3-(acryloyloxy)propyltrimethoxysilane, 3-isocyanatepropyltriethoxysilane, 3-isocyanatepropyltrimethoxysilane, 3-glycidoxypropyltrimethoxysilane, vinyltrimethoxysilane, allyltrimethoxysilane, 1-hexynyltrimethoxysilane, 1-octenyltrimethoxysilane, (phenylaminomethyl)methyldimethoxysilane, N-phenylaminopropyltrimethoxysilane, 3-(4-pyridylethyl)thiopropyltrimethoxysilane, N-(3-trimethoxysilylpropyl)pyrrole, 2-(3-trimethoxysilylpropylthio)thiophene, (3-trimethoxysilylpropyl (2-diphenylphosphino)ethyl dimethylethoxysilane, 2-(diphenylphosphino)ethyl triethoxysilane, 3-(diphenylphosphino)propyl triethoxysilane, heptanol, hexanol, octanol, benzyl alcohol, phenols, ethanol, propanol, butanol, oleyl alcohol, dodecyl alcohol, octadecanol, triethylene glycol monomethyl ether terephthalic acid, octanoic acid, acetic acid, propionic acid, 2-[2-(2-methoxyethoxy)ethoxy]acetic acid, oleic acid, benzoic acid, stearic acid, trifluoroacetic acid, biphenyl-4-carboxylic acid, 2-(2-methoxyethoxy)acetic acid, methacrylic acid, mono-2-(methacryloyloxy)ethylsuccinic acid, 2-mercaptoethanol, 2-{2-[2-(2-mercaptoethoxy)ethoxy)ethoxy]ethoxy}ethanol, 2-(2-methoxyethoxy)ethanethiol, 1-octanethiol, 2,3-Dimercaptopropane Sodium Sulfate Monohydrate, Sodium Dodecyl Sulfate, Dodecylphosphonic Acid, Octylphosphonic Acid, (11-Mercaptoundecyl)phosphonic Acid, (11-(acryloyloxy)undecyl)phosphonic Acid, 11-Methacryloyloxyundecylphosphonic Acid, [2-[2-(2-Methoxyethoxy)ethoxy]ethyl]phosphonic Acid Ethyl Ester, and combinations thereof.

[0086] The acrylic monomers, oligomers, and / or polymers of the formulations of the present disclosure may be selected from the group consisting of benzyl (meth)acrylate (BA and BMA), trimethylolpropane tri(meth)acrylate (TMPTA and TMPTMA), trimethylolpropane ethoxylate tri(meth)acrylate (EOTMPTA and EOTMPTMA), 1,6-hexanediol di(meth)acrylate (HDDA and HDDMA), di(ethylene glycol) di(meth)acrylate (DEGDA and DEGDMA), ethylene glycol diacrylate, glycerol 1,3-diglycerolate diacrylate, tri(propylene glycol) diacrylate, 1,6-hexanediol ethoxylate diacrylate, ethylene glycol phenoxylate ... and / or sulfur-containing monomers and resins derived from or having the following molecular structures or combinations thereof: phenyl ether (meth)acrylates (PEA and PEMA), 2-hydroxy-3-phenoxypropyl acrylate (HPPA), 2-hydroxy-3-phenoxypropyl methacrylate (HPPMA), 2-phenoxybenzyl acrylate (PBA), biphenyl methacrylate (BPMA), 2-phenylphenol methacrylate (PPMA), isobutyl acrylate (IBA), 2-phenylethyl acrylate (2-PEA), 2-(phenylthio)ethyl acrylate (PTEA), tris(2-hydroxyethyl)isocyanurate triacrylate (THEICTA), high refractive index, and / or sulfur-containing monomers and resins derived from or having the following molecular structures or combinations thereof:

[0087] [ka]

[0088] [ka]

[0089] The vinyl monomers, oligomers, and / or polymers of the formulations of the present disclosure include N-vinylpyrrolidone (NVP), phenylnorbornene, styrene (STY), 4-methylstyrene, 4-vinylanisole, divinylbenzene, or combinations thereof.

[0090] The hardener of the formulation of the present disclosure includes a photoinitiator. Any photoinitiator may be used as long as it is capable of generating active species such as radicals using light (UV) energy, provided that it does not limit the optical and physical performance of the nanocomposite. Photoinitiator hardeners include amines such as Ebecryl® P115, CN374, benzophenone and its derivatives such as Esacure 1001M or Ebecryl® P39, benzophenone, organic phosphines such as SpeedCure BEM (Lambson USA Ltd, Rutherford, Connecticut, USA) or diphenyl(2,4,6-trimethylbenzoyl)-phosphine oxide (TPO), Irgacure® 819, or Irgacure® 184 (BASF USA, Florham Park, New Jersey, USA), or ITX. The formulation includes a single photoinitiator or any combination thereof. The formulations described herein focus on the application of UV light for cure, although thermal cure is also entirely possible using a suitable thermal initiator such as 2,2-azobis(2-methylpropionitrile) (AIBN).

[0091] Combinations of more than one curing agent may be advantageous in certain circumstances known to those skilled in the art. The amount of curing agent in the formulation of the present disclosure is less than 0.5% by weight of the total monomer, oligomer, and / or polymer, or 0.5% to 1% by weight of the total monomer, oligomer, and / or polymer, or 1% to 2% by weight of the total monomer, oligomer, and / or polymer, or 2% to 3% by weight of the total monomer, oligomer, and / or polymer, or 3% to 4% by weight of the total monomer, oligomer, and / or polymer, or 4% to 5% by weight of the total monomer, oligomer, and / or polymer, or 5% to 6% by weight of the total monomer, oligomer, and / or polymer, or 6% to 7% by weight of the total monomer, oligomer, and / or polymer, or 7% to 8% by weight of the total monomer, oligomer, and / or polymer, or 8% to 15% by weight of the total monomer, oligomer, and / or polymer.

[0092] The adhesion promoter, if present, is selected from organometallic compounds such as organofunctional silanes or from functionalized monomers and oligomers. Some suitable organofunctional silane adhesion promoters contain amino or methacryloxy groups. Exemplary silane adhesion promoters include, but are not limited to, 3-aminopropyltriethoxysilane, 3-[(methacryloyloxy)propyl]trimethoxysilane, ureidopropyltrimethoxysilane, and trimethoxy[3-(methylamino)propyl]silane. Functionalized monomers and oligomers adhesion promoters include, but are not limited to, CN820, CN146 (Sartomer Americas, Exton, Pennsylvania, USA), SR9051, SR9053 (Sartomer Americas, Exton, Pennsylvania, USA), and Ebecryl171 (Allnex USA Inc., Wallingford, Connecticut, USA).

[0093] The adhesion promoter of the formulation of the present disclosure is present in an amount of less than 0.5% by weight of the monomer, oligomer, and / or polymer, or from 0.5 to 1% by weight of the monomer, oligomer, and / or polymer, or from 1 to 5% by weight of the monomer, oligomer, and / or polymer, or from 5 to 10% by weight of the monomer, oligomer, and / or polymer, or from 10 to 15% by weight of the monomer, oligomer, and / or polymer, or from 15 to 30% by weight of the monomer, oligomer, and / or polymer.

[0094] Surfactants, which can act as wetting agents, leveling agents, defoamers and dispersants, are present to improve the flow of the formulation by reducing the surface tension of the formulation, resulting in a more uniform dried coating surface. The surfactants are nonionic, anionic, or a combination thereof. Representative examples of suitable wetting agents include, but are not limited to, siloxane surfactants such as BYK-331, BYK-377, BYK-378, (BYK Chemie, GMBH) and fluorosurfactants such as Novec 4430, Novec 4432, and Novec 4434 (3M, St. Paul, Minnesota, USA), and Capstone FS-3100 (The Chemours Company, Wilmington, Delaware, USA).

[0095] Examples of leveling agents, if present, are polyacrylate compounds such as BYK-352, BYK-353, BYK-356, and BYK-361N, aralkyl-modified polymethylalkylsiloxanes such as BYK-322, BYK-323, and BYK-350 (BYK Chemie, GMBH), and polyether-modified, acryl-functional siloxanes such as BYK-UV 3530. Examples of dispersing agents include, but are not limited to, polyalkylene glycols and their esters, polyoxyalkylenes, polyhydric alcohol ester alkylene oxide adducts, alcohol alkylene oxide adducts, sulfate esters, sulfate salts, carboxylate esters, carboxylate salts, alkylamide alkylene oxide adducts, and alkylamines, used alone or as a mixture of two or more.

[0043] Examples of commercially available dispersants are DISPERBYK-101, DISPERBYK-130, DISPERBYK-140, DISPERBYK-160, DISPERBYK-161, DISPERBYK-162, DISPERBYK-163, DISPERBYK-164, DISPERBYK-165, DISPERBYK-166, DISPERBYK-170, DISPERBYK-171, DISPERBYK-182, DISPERBYK-2000, DISPERBYK-2001 (BYK Chemie, GMBH), Solsperse 32000, Solsperse 36000, Solsperse 28000, Solsperse 20000, Solsperse 41000, and Solsperse 45000 (Lubrizol, Wickliffe, Ohio, USA), but is not limited to it.

[0096] For purposes of improving wettability, the amount of surfactant in the formulation of the present disclosure is less than 0.05% by weight of the total formulation, or 0.05-0.1% by weight of the total formulation, or 0.1-0.5% by weight of the total formulation, or 0.5-1% by weight of the total formulation, or 1-2% by weight of the total formulation, or 2-5% by weight of the total formulation. For purposes of aiding in dispersion, the amount of surfactant in the formulation of the present disclosure varies depending on the dispersed material. The amount of dispersant is less than 3% by weight of the dispersed material, or 3-5% by weight of the dispersed material, or 5-10% by weight of the dispersed material, or 10-20% by weight of the dispersed material, or 20-40% by weight of the dispersed material, or 40-60% by weight of the dispersed material, or 60-80% by weight of the dispersed material, or 80-100% by weight of the dispersed material, or 100-150% by weight of the dispersed material.

[0097] The antioxidant of the formulation of the present disclosure comprises at least one primary antioxidant selected from sterically hindered phenols such as Irganox 1010, Irganox 1076, SongNox® 1076, SongNox® 2450, or phenol phosphites such as SongNox® 1680, or phosphines such as Irgaphos 168 (BASF USA, Florham Park, NJ, USA) or aromatic secondary amines or hindered amines such as SongLight® 6220 (Songwon Americas, Friendwood, TX, USA).

[0098] The formulation of the present disclosure optionally contains at least one secondary antioxidant. The secondary antioxidant is preferably selected from compounds containing at least one unit formed from a sulfur atom bonded to two carbon atoms. Representative examples of secondary antioxidants are di(t-butyl)hydroxyphenylaminobisoctylthiotriazine and Irganox PS800 (BASF USA, Florham Park, NJ, USA).

[0099] The amount of antioxidant in the formulation of the present disclosure is less than 0.5% by weight of the total formulation, or between 0.5% and 1% by weight of the total formulation, or between 1% and 2% by weight of the total formulation, or between 2% and 3% by weight of the total formulation, or between 3% and 4% by weight of the total formulation, or between 4% and 5% by weight of the total formulation, or between 5% and 6% by weight of the total formulation, or between 6% and 7% by weight of the total formulation, or between 7% and 8% by weight of the total formulation, or between 8% and 10% by weight of the total formulation.

[0100] The formulations of the present disclosure may further include plasticizers, tougheners, thickeners, thinners, dispersants, or softeners, or other functional additives. The formulations of the present disclosure may further include a solvent, the choice of solvent being dependent solely on the type of capped zirconia and the monomers, oligomers and polymers of the formulation selected. Examples of common solvents ranging from low to high boiling points are alcohols, glycols, methyl acetate, ethyl acetate, esters, ketones, glycol ethers, glycol esters such as propylene glycol monomethyl ether acetate (PGMEA), propylene glycol monomethyl ether (PGME), ethylene glycol monobutyl ether acetate, diethylene glycol monobutyl ether acetate, diethylene glycol butyl ether, diethylene glycol monoethyl ether acetate, dipropylene glycol methyl ether acetate, butoxyethanol, butoxypropanol, ethyl ethoxyacetate, ethyl butoxyacetate, 2-(isopentyloxy)ethanol, 2-(hexyloxy)ethanol, diethylene glycol, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, triethylene glycol, triethylene glycol monomethyl ether, dipropylene glycol, dipropylene glycol monomethyl ether, and dipropylene glycol monoethyl ether, ethyl acetate, THF, acetone, or any combination thereof.

[0101] The formulations of the present disclosure have adjustable viscosities and / or viscosities that can be controlled by one or more components of the formulation. Parameters that can control the viscosity of the formulation include, but are not limited to, the average length and molecular weight of the monomers, oligomers, and / or polymers; and the presence and concentration of solvents, the presence and concentration of thickeners (i.e., viscosity modifying components), particle sizes of the components present in the formulation, temperature, and combinations thereof.

[0102] The formulations of the present disclosure are stable for more than 1 week, or more than 2 weeks, or more than 3 weeks, or more than 6 weeks, or more than 8 weeks, or more than 3 months, or more than 6 months, or more than 12 months, or more than 36 months, without any significant increase in viscosity. There should be no visible precipitation of capped nanocrystals, and the viscosity of the formulation should change by less than 10%, or less than 20%, or less than 30%, or less than 40%, or less than 50%, or less than 100%. Additionally, the optical transmittance of the formulation should change by less than 10% decrease in transmittance at 450 nm, or less than 20% decrease in transmittance, or less than 30% decrease in transmittance, or less than 40% decrease in transmittance, or less than 50% decrease in transmittance.

[0103] The jetting of the formulations of the present disclosure for inkjet printing purposes is stable for more than 1 hour, more than 8 hours, more than 1 day, or more than 1 week without significant increase in viscosity. The formulations do not solidify by drying or curing leading to clogging of print head nozzles.

[0104] Methods for preparing solvent-free or solvent-containing nanocomposite formulations In some embodiments, the present disclosure provides methods for the preparation of solvent-free or solvent-containing nanocomposite formulations as exemplified herein below.

[0105] 1. A method for making a solvent-free nanocomposite formulation comprising direct dispersion (dispersing nanocrystals directly in a medium), in which capped zirconia and titania nanocrystals are separated from the solvent and dried under vacuum to a solvent content of less than 5% to form dried nanocrystals; mixing the dried at least partially capped zirconium oxide nanocrystals and titanium oxide nanocrystals into at least one monomer, oligomer, polymer or mixture thereof and other formulation components by immersion, stirring, high speed mixing, microfluidization or other mixing methods; A method comprising:

[0106] In some embodiments, method 1 further comprises filtering the mixture to remove aggregates or other contaminants. 2. mixing the dried powder of at least partially capped zirconium oxide and titanium oxide nanocrystals in at least one solvent by immersion, stirring, high speed mixing, microfluidization or other mixing methods to provide a nanocrystal solvent dispersion; mixing said dispersion with at least one monomer, oligomer, polymer or mixture of monomers, oligomers and / or polymers and other formulation ingredients to provide a solvent-containing formulation; removing said solvent by evaporation or other solvent removal methods such as rotovap. A method for making another solvent-free formulation comprising:

[0107] In some embodiments, method 2 may further comprise filtering the solvent-containing or solvent-free formulation to remove aggregates or other contaminants. Non-limiting useful solvents for Method 2 include ethyl acetate, methyl ethyl ketone, or other low boiling point solvents.

[0108] 3. mixing the dried powder of at least partially capped zirconium oxide and titanium oxide nanocrystals in at least one solvent by immersion, stirring, high speed mixing, microfluidization or other mixing methods to provide a nanocrystal solvent dispersion; mixing said dispersion with at least one monomer, oligomer, polymer or mixture of monomers, oligomers and / or polymers and other formulation ingredients to provide a solvent-containing formulation; In some embodiments, method 3 may further comprise filtering the solvent-containing formulation to remove aggregates or other contaminants.

[0109] Nanocomposite Properties A nanocomposite is a film, coating, layer, lens or free-standing structure on a substrate. The present disclosure provides a nanocomposite comprising a mixture of an organic polymerizable matrix, a curing agent, and capped nanocrystals, such as zirconia or titania nanocrystals, wherein the capped nanocrystals are present in the nanocomposite in an amount of 20-95% by weight of the nanocomposite.

[0110] The capping agents of the capped zirconia and titania nanocrystals in the nanocomposites of the present disclosure include organic silanes, organic carboxylic acids and / or organic alcohols. Examples of capping agents include methyltrimethoxysilane, n-propyltrimethoxysilane, n-propyltriethoxysilane, n-octyltrimethoxysilane, n-octyltriethoxysilane, phenyltrimethoxysilane, dodecyltrimethoxysilane, m,p-Ethylphenethyltrimethoxysilane, 2-[methoxy(polyethyleneoxy)propyl]-trimethoxysilane, methoxy(triethyleneoxy)propyltrimethoxysilane, 3-aminopropyltrimethoxysilane, 3-mercaptopropyltrimethoxysilane, 3-(methacryloyloxy)propyltrimethoxysilane, 3-(acryloyloxy)propyltrimethoxysilane, 3-isocyanatepropyltriethoxysilane, 3-isocyanatepropyltrimethoxysilane, 3-glycidoxypropyltrimethoxysilane, vinyltrimethoxysilane, allyltrimethoxysilane, 1-hexynyltrimethoxysilane, 1-octenyltrimethoxysilane, (phenylaminomethyl)methyldimethoxysilane, N-phenylaminopropyltrimethoxysilane, 3-(4-pyridylethyl)thiopropyltrimethoxysilane, N-(3-trimethoxysilylpropyl)pyrrole, 2-(3-trimethoxysilylpropylthio)thiophene, (3-trimethoxysilylpropyl (2-diphenylphosphino)ethyl dimethylethoxysilane, 2-(diphenylphosphino)ethyl triethoxysilane, 3-(diphenylphosphino)propyl triethoxysilane, heptanol, hexanol, octanol, benzyl alcohol, phenols, ethanol, propanol, butanol, oleyl alcohol, dodecyl alcohol, octadecanol, triethylene glycol monomethyl ether terephthalic acid, octanoic acid, acetic acid, propionic acid, 2-[2-(2-methoxyethoxy)ethoxy]acetic acid, oleic acid, benzoic acid, stearic acid, trifluoroacetic acid, biphenyl-4-carboxylic acid, 2-(2-methoxyethoxy)acetic acid, methacrylic acid, mono-2-(methacryloyloxy)ethylsuccinic acid, 2-mercaptoethanol, 2-{2-[2-(2-mercaptoethoxy)ethoxy)ethoxy]ethoxy}ethanol, 2-(2-methoxyethoxy)ethanethiol, 1-octanethiol, 2,3-Dimercaptopropane Sodium Sulfate Monohydrate, Sodium Dodecyl Sulfate, Dodecylphosphonic Acid, Octylphosphonic Acid, (11-Mercaptoundecyl)phosphonic Acid, (11-(acryloyloxy)undecyl)phosphonic Acid, 11-Methacryloyloxyundecylphosphonic Acid, [2-[2-(2-Methoxyethoxy)ethoxy]ethyl]phosphonic Acid Ethyl Ester, and combinations thereof.

[0111] The inorganic solids concentration of the nanocomposites of the present disclosure (e.g., nanocomposite coatings or films) is analyzed using a TA instrument Q500 thermogravimetric analyzer (TGA). The procedure is the same as previously described. The percentage of the initial mass at 700°C is considered the inorganic portion of the formulation, i.e., the solids concentration.

[0112] The inorganic solids concentration of the nanocomposites of the present disclosure (e.g., nanocomposite coatings or films) is 0-10% as measured by TGA, or 10-20% as measured by TGA, or 20-30% as measured by TGA, or 30-40% as measured by TGA, or 40-50% as measured by TGA, or 50-60% as measured by TGA, or 60-70% as measured by TGA, or 70-80% as measured by TGA, or 80-90% as measured by TGA, or 90-93% as measured by TGA.

[0113] The refractive index at 589 nm of the nanocomposites (e.g., nanocomposite coatings or films) of the present disclosure can be 1.54 to 1.56, 1.56 to 1.58, 1.58 to 1.60, 1.60 to 1.62, or 1.62 to 1.64, 1.64 to 1.66, or 1.66 to 1.68, or 1.68 to 1.70, or 1.70 to 1.72, or 1.72 to 1.74, or 1.74 to 1.76, or 1.76 to 1.78, or 1.78 to 1.80. , or 1.80 to 1.82, or 1.82 to 1.84, or 1.84 to 1.86, or 1.86 to 1.88, or 1.88 to 1.90, 1.90 to 1.92, or 1.92 to 1.94, or 1.94 to 1.96, or 1.96 to 1.98, or 1.98 to 2.00, or 2.00 to 2.02, or 2.02 to 2.04, or 2.04 to 2.06, or 2.06 to 2.08, or 2.08 to 2.10, or greater than 2.10.

[0114] The hardness values ​​measured using nanoindentation of nanocomposites (e.g., nanocomposite coatings or films) of the present disclosure are from 1 to 5 MPa, or from 5 to 20 MPa, or from 20 to 50 MPa, or from 50 to 100 MPa, or from 100 to 150 MPa, or from 150 to 200 MPa, or from 200 to 250 MPa, or from 250 to 300 MPa, or from 300 to 350 MPa, or from 350 to 400 MPa.

[0115] The nanocomposites (e.g., nanocomposite coatings or films) of the present disclosure may have modulus values ​​measured using nanoindentation of 0.1-0.5 GPa, or 0.5-1.0 GPa, or 1.0-1.5 GPa, or 1.5-2.0 GPa, or 2.0-2.5 GPa, or 2.5-3.0 GPa, or 3.0-3.5 GPa, or 3.5-4.0 GPa. , or 4.0-4.5 GPa, or 4.5-5.0 GPa, or 5.0-5.5 GPa, or 5.5-6.0 GPa, or 6.0-6.5 GPa, or 6.5-7.0 GPa, or 7.0-7.5 GPa, or 7.5-8.0 GPa, or 8.0-8.5 GPa, or 8.5-9.0 GPa, or 9.0-9.5 GPa, or 9.5-10.0 GPa.

[0116] The high optical transmittance at 400 nm or greater of the nanocomposites (e.g., nanocomposite coatings or films) of the present disclosure for films less than 20 microns thick is 99.9%-99%, or 99%-98%, or 98%-97%, or 97%-96%, or 96%-95%, or 95%-90%, or 90%-85%, or 85%-80%, or 80%-75%, or 75%-70%, or 70%-65%, or 65%-60%, or 60%-55%, or 55%-50%, or 50%-45%, or 45%-40%, or 40%-35%, or 35%-30%, or 30%-25%, or 25%-20%, or 20%-15%, or 15%-10%. The transmittance of the films according to the present disclosure is the standard transmittance measured using a Perkin-Elmer UV-Vis Lambda 850 spectrophotometer, where the nanocomposite is coated on an optically transparent substrate such as a fused silica or glass substrate, and a blank substrate of the same type and thickness is used as a reference. The nanocomposites of the present disclosure have high optical transmittance at 450 nm or greater for films less than 20 microns thick, from 99.9% to 99%, or 99%-98%, or 98%-97%, or 97%-96%, or 96%-95%, or 95%-90%, or 90%-85%, or 85%-80%, or 80%-75%, or 75%-70%, or 70%-65%, or 65%-60%, or 60%-55%, or 55%-50%, or 50%-45%, or 45%-40%, or 40%-35%, or 35%-30%, or 30%-25%, or 25%-20%, or 20%-15%, or 15%-10%.

[0117] The nanocomposites of the present disclosure additionally demonstrate thermal stability at temperatures greater than 120° C., or greater than 175° C., or greater than 200° C., or greater than 250° C., or greater than 260° C., or greater than 300° C., as measured by placing the nanocomposite under air, nitrogen, or vacuum for 5 minutes or more, or 10 minutes or more, or 30 minutes or more, or 60 minutes or more, or 120 minutes or more at the specified temperature without visually observable coloration, cracking, or delamination, and with less than a 10% decrease in transmittance at 400 nm, or less than a 20% decrease in transmittance, or less than a 30% decrease in transmittance, or less than a 40% decrease in transmittance, or less than a 50% decrease in transmittance.

[0118] Methods for preparing nanocomposites The present disclosure provides methods for making nanocomposites using any of the formulations of the present disclosure. Nanocomposite films containing the formulations of the present disclosure that have been cured or partially cured are described herein. The nanocomposites are cured or partially cured by UV or thermal curing methods known to those skilled in the art.

[0119] The present disclosure provides a nanocomposite film as described herein, wherein the film is produced by spin coating, slot die coating, screen printing, inkjet printing, dip coating, draw bar coating, roll-to-roll printing, spray coating, or any combination thereof.

[0120] device The present disclosure provides an LED, organic LED, touch screen, display, sensor, augmented reality, virtual reality or solar cell device comprising an active component, said active component comprising or containing the nanocomposite of the present disclosure.

[0121] ZrO2 and TiO2 nanocrystal capping Methods for preparing at least partially capped ZrO2 and TiO2 nanocrystals useful in embodiments of the present disclosure, such as the blends or nanocomposites herein, are exemplified below.

[0122] ZrO2 and TiO2 nanocrystals were synthesized via a solvothermal method similar to the process described in patent numbers, US8592511B2 and PCT / US2019 / 062439 (published as WO2020 / 106860). The as-synthesized ZrO2 and TiO2 nanocrystals were transferred to a flask. Solvent: Nanocrystals 0.1:1~1:1, 1:1~1.25:1, 1.25:1~1.5:1, 1.5:1~1.75:1, 1.75:1~2:1, 2:1~2.25:1, 2.25:1~2.5:1, 2.5:1~2.75:1, 2.75:1~3:1, 3:1~4:1, 4:1~5:1, 5:1~6:1, 6:1~7:1, 7:1~8:1, 8:1~9:1, 9:1~10:1 with the addition of a solvent such as PGMEA or toluene. Then, a first capping agent was added to the reaction flask in weight ratios of 0.1-5%, 5-10%, 10-15%, 15-20%, 20-25%, 25%-30%, 30%-35% of the capping agent to the wet cake, and the mixture was then heated to 50-60, 60-70, 70-80, 80-90, 90-100, 100-110, 110-120, 120-130°C for 1-10, 10-20, 20-30, 30-40, 40-50, 50-60, 60-70, 70-80, 80-90, 90-100, 10 ...

[0123] Optionally, a second capping agent was added to the reaction flask before or after the first heating process. A second capping agent was also added to the reaction flask at a weight ratio of capping agent to wet cake of 0.1-5%, 5-10%, 10-15%, 15-20%, 20-25%, 25%-30%, 30%-35%, 35%-40%, 40%-45%, 45%-50%, 50%-55%, 55%-60%, 60%-70%, 70%-80%, 80%-90%, 90%-100%. The mixture was then heated to 50-60, 60-70, 70-80, 80-90, 90-100, 100-110, 110-120, or 120-130° C. for 1-10, 10-20, 20-30, 30-40, 40-50, 50-60, 60-70, 70-80, 80-90, 90-100, or 100-120 minutes. The reaction mixture was then cooled to 80° C., and water was then optionally added to the reaction mixture at a weight ratio of water to wet cake of 0.1-5%, 5-10%, 10-15%, 15-20%, 20-25%, 25%-30%, or 30%-35%. The mixture is heated at 80-90, 90-100, 100-110, 110-120, or 120-130° C. for an additional 1-10, 10-20, 20-30, 30-40, 40-50, 50-60, 60-70, 70-80, 80-90, 90-100, or 100-120 minutes. The reaction mixture is then cooled to room temperature to provide capped nanocrystals. The capped nanocrystals may then be filtered through a 0.45 micron and then a 0.2 micron PTFE filter, or optionally through a washing process as described below.

[0124] The surface of the ZrO2 and / or TiO2 nanocrystals of the present disclosure may be modified with any of a variety of silanes, including, but not limited to, methyltrimethoxysilane, n-propyltrimethoxysilane, n-propyltriethoxysilane, n-octyltrimethoxysilane, n-octyltriethoxysilane, phenyltrimethoxysilane, dodecyltrimethoxysilane, m,p-Ethylphenethyltrimethoxysilane, 2-[methoxy(polyethyleneoxy)propyl]-trimethoxysilane, methoxy(triethyleneoxy)propyltrimethoxysilane, 3-aminopropyltrimethoxysilane, 3-mercaptopropyltrimethoxysilane, 3-(methacryloyloxy)propyltrimethoxysilane, 3-(acryloyloxy)propyltrimethoxysilane, 3-isocyanatepropyltriethoxysilane, 3-isocyanatepropyltrimethoxysilane, 3-glycidoxypropyltrimethoxysilane, vinyltrimethoxysilane, allyltrimethoxysilane, 1-hexynyltrimethoxysilane, 1-octenyltrimethoxysilane, (phenylaminomethyl)methyldimethoxysilane, N-phenylaminopropyltrimethoxysilane, 3-(4-pyridylethyl)thiopropyltrimethoxysilane, N-(3-trimethoxysilylpropyl)pyrrole, 2-(3-trimethoxysilylpropylthio)thiophene, (3-trimethoxysilylpropyl (2-diphenylphosphino)ethyl dimethylethoxysilane, 2-(diphenylphosphino)ethyl triethoxysilane, 3-(diphenylphosphino)propyl triethoxysilane, heptanol, hexanol, octanol, benzyl alcohol, phenols, ethanol, propanol, butanol, oleyl alcohol, dodecyl alcohol, octadecanol, triethylene glycol monomethyl ether terephthalic acid, octanoic acid, acetic acid, propionic acid, 2-[2-(2-methoxyethoxy)ethoxy]acetic acid, oleic acid, benzoic acid, stearic acid, trifluoroacetic acid, biphenyl-4-carboxylic acid, 2-(2-methoxyethoxy)acetic acid, methacrylic acid, mono-2-(methacryloyloxy)ethylsuccinic acid, 2-mercaptoethanol, 2-{2-[2-(2-mercaptoethoxy)ethoxy)ethoxy]ethoxy}ethanol, 2-(2-methoxyethoxy)ethanethiol, 1-octanethiol, 2,Optionally capped with at least one capping agent including sodium 3-dimercaptopropane sulfate monohydrate, sodium dodecyl sulfate, dodecylphosphonic acid, octylphosphonic acid, (11-mercaptoundecyl)phosphonic acid, (11-(acryloyloxy)undecyl)phosphonic acid, 11-methacryloyloxyundecylphosphonic acid, [2-[2-(2-methoxyethoxy)ethoxy]ethyl]phosphonic acid ethyl ester, and combinations thereof.

[0125] The reaction mixture is optionally washed to remove excess capping agent and other by-products. The reaction mixture is precipitated by adding an anti-solvent, such as heptane in the case of a PGMEA solution or acetone in the case of a toluene solution, in a weight to weight ratio of anti-solvent to the reaction mixture of 0.1:1 to 1:1, 1:1 to 1.25:1, 1.25:1 to 1.5:1, 1.5:1 to 1.75:1, 1.75:1 to 2:1, 2:1 to 2.25:1, 2.25:1 to 2.5:1, 2.5:1 to 2.75:1, 2.75:1 to 3:1. This precipitate is 100~500, 500~1000, 100~1500, 1500~2000, 2000~2500, 2500~3000, 3000~3500, 3500~4000, 4000~4500, 4500~5000, 5000~5500, 5500~6000, 6000~6500 The solids were centrifuged at 6500-7000, 7000-7500, 7500-8000, 8000-8500, and 8500-9000 rpm for 0-5, 5-10, 10-15, 15-20, 30-25, 25-30, 30-35, 35-40, 40-45, 45-50, 50-55, and 55-60 minutes. The resulting supernatant was decanted and discarded. The solids were then dispersed in a solvent such as toluene in the case of capped nonpolar nanocrystals or THF in the case of capped polar nanocrystals. The dispersed solids were then reprecipitated into a poor solvent such as heptane in the case of the THF solution or acetone in the case of the toluene solution in a weight to weight ratio of poor solvent to the reaction mixture of 0.1:1 to 1:1, 1:1 to 1.25:1, 1.25:1 to 1.5:1, 1.5:1 to 1.75:1, 1.75:1 to 2:1, 2:1 to 2.25:1, 2.25:1 to 2.5:1, 2.5:1 to 2.75:1, 2.75:1 to 3:1.This precipitate is 100~500, 500~1000, 100~1500, 1500~2000, 2000~2500, 2500~3000, 3000~3500, 3500~4000, 4000~4500, 4500~5000, 5000~5500, 5500~6000, 6000~6500 The solids were centrifuged at 6500-7000, 7000-7500, 7500-8000, 8000-8500, and 8500-9000 rpm for 0-5, 5-10, 10-15, 15-20, 30-25, 25-30, 30-35, 35-40, 40-45, 45-50, 50-55, and 55-60 minutes. The resulting supernatant was decanted and discarded. This process was repeated if necessary. The solids were then placed in a vacuum oven to dry overnight.

[0126] The optionally dried solids (capped nanocrystals) were then redispersed in PGMEA at a 1:1 solid to solvent ratio to produce a 50 wt% loaded dispersion, and the resulting dispersion was filtered through a 0.45 micron and then a 0.2 micron PTFE filter.

[0127] Example: Capped ZrO2 nanocrystals Methods for preparing at least partially capped ZrO2 nanocrystals useful in embodiments of the present disclosure, such as the formulations or nanocomposites herein, are further illustrated below.

[0128] The as-synthesized ZrO2 nanocrystals, hereafter referred to as "wet cake", were transferred to a round bottom flask. Then, PGMEA was added in a solvent to wet cake weight ratio of 0.370:1. Along this line, 10 wt% of the wet cake methoxy(triethyleneoxy)propyltrimethoxysilane was added to the reaction flask. Then, 2 wt% of the wet cake 3-(acryloyloxy)propyltrimethoxysilane was added to the reaction flask. This mixture was heated to 120°C for 90 minutes with stirring to form the capped nanocrystals. Finally, the reaction mixture was cooled to room temperature.

[0129] The reaction mixture was then washed to remove excess capping agent and impurities. The reaction mixture was then precipitated using heptane as an anti-solvent with a weight to weight ratio of heptane to the reaction mixture of 7:1. The precipitate was centrifuged at 4500 rpm for 10 minutes. The resulting supernatant was decanted and discarded. The solid was then dispersed in THF with a weight to weight ratio of THF to solids of 3:1. The dispersed solid with a weight to weight ratio of 3:1 heptane to the reaction mixture was then precipitated again in an anti-solvent such as heptane. The precipitate was centrifuged at 4500 rpm for 10 minutes. The resulting supernatant was decanted and discarded. The solid was then dispersed in THF with a weight to weight ratio of 3:1 THF to solids. The dispersed solid with a weight to weight ratio of 3:1 heptane to the reaction mixture was then precipitated a third time in an anti-solvent such as heptane. The precipitate was centrifuged at 4500 rpm for 10 minutes. The resulting supernatant was decanted and discarded. The solid was then dispersed in THF with a weight to weight ratio of 3:1 THF to solids. The dispersed solid with a weight to weight ratio of 3:1 heptane to the reaction mixture was then precipitated a third time in an anti-solvent such as heptane. The resulting supernatant was decanted and discarded, and the solid was then placed in a vacuum oven to dry overnight.

[0130] The dried solids were redispersed in solvent or monomer and optionally filtered through 0.45 micron and then 0.2 micron PTFE filters. Example: Capped TiO2 nanocrystals Methods for preparing at least partially capped TiO2 nanocrystals useful in embodiments of the present disclosure, such as the formulations or nanocomposites herein, are further illustrated below.

[0131] The as-synthesized TiO2 nanocrystals, hereafter referred to as "wet cake", were transferred to a round bottom flask. PGMEA was then added in a solvent to wet cake weight ratio of 1.857:1. Along with this process, 15 wt% of the wet cake, methoxy(triethyleneoxy)propyltrimethoxysilane, was added to the reaction flask. The mixture was heated to 120°C with stirring for 40 minutes to form partially capped nanocrystals. 30 wt% of the wet cake, methacryloxypropyltrimethoxysilane, was added to the reaction flask and the mixture was heated at 120°C with stirring for another 30 minutes to form capped nanocrystals. The reaction mixture was then cooled to 100°C, after which 5 wt% of the wet cake, water was added and the mixture was heated at 100°C for 30 minutes. Finally, the reaction mixture was cooled to room temperature.

[0132] The reaction mixture was then washed to remove excess capping agent and impurities. The reaction mixture was then precipitated using heptane as an anti-solvent with a weight to weight ratio of heptane to the reaction mixture of 3:1. The precipitate was centrifuged at 3000 rpm for 10 minutes. The resulting supernatant was decanted and discarded. The solid was then dispersed in THF with a weight to weight ratio of THF to solids of 3:1. The dispersed solid was then precipitated again in a weight to weight ratio of 3:1 heptane to the reaction mixture in an anti-solvent such as heptane. The precipitate was centrifuged at 3000 rpm for 10 minutes. The resulting supernatant was decanted and discarded. The solid was then dispersed in THF with a weight to weight ratio of 3:1 THF to solids. The dispersed solid was then precipitated a third time in a anti-solvent such as heptane. The precipitate was centrifuged at 3000 rpm for 10 minutes. The resulting supernatant was decanted and discarded. The solid was then dispersed in THF with a weight to weight ratio of 3:1 THF to solids. The dispersed solid was then precipitated a third time in a weight to weight ratio of 3:1 heptane to the reaction mixture in an anti-solvent such as heptane. The resulting supernatant was decanted and discarded. The solid was then placed in a vacuum oven to dry overnight. The dried solid was redispersed in solvent or monomer and optionally filtered through a 0.45 micron and then a 0.2 micron PTFE filter.

[0133] The dispersion characteristics of exemplary TiO2 and ZrO2 nanocrystals are illustrated in Figure 1. The TiO2 nanocrystals with an average core diameter of 5 nm shown in the transmission electron microscopy (TEM) image of Figure 1a have been surface modified or capped with a capping agent that makes the nanocrystals compatible with a variety of monomers and polymers, including acrylates, epoxies, and siloxanes. The capping agent is designed for maximum compatibility with the polymer matrix. The capped nanocrystals form a uniform dispersion in propylene glycol monomethyl ether acetate (PGMEA) with a single narrow dynamic light scattering (DLS) peak (Figure 1b) centered at approximately 10 nm.

[0134] The TiO2 nanocrystals with an average core diameter of 15 nm shown in the TEM image in Figure 1c were capped with a capping agent that rendered the nanocrystals compatible with many monomers and polymers, including acrylates, epoxies, and siloxanes. These capped nanocrystals also formed homogeneous dispersions in PGMEA with a single narrow DLS peak centered at approximately 20 nm (Figure 1d).

[0135] TEM images (Figure 1e) show ZrO2 nanocrystals with an average core diameter of 5 nm that are capped with a capping agent that makes them compatible with a variety of monomers and polymers, including acrylates, epoxies, and siloxanes. These capped nanocrystals also form homogeneous dispersions in PGMEA with a single narrow DLS peak centered at approximately 8 nm (Figure 1f). EXAMPLES

[0136] In the following examples, the above-mentioned capped ZrO2 and / or TiO2 nanocrystals were used. Those skilled in the art may also use hafnium oxide, zinc oxide, tantalum oxide, niobium oxide, and combinations thereof in addition to or in place of TiO2 and ZrO2 nanocrystals. Those skilled in the art will recognize that ZrO2 and / or TiO2 nanocrystals with different capping agents may also be used. The examples are merely illustrative and are not intended to limit the claimed invention in any manner.

[0137] Example 1 (solvent ZrO2) The above capped ZrO2 nanocrystals in "Example Capped ZrO2 Nanocrystals" were prepared by incorporating desired monomers such as BPMA and PTEA in combination with BMTPS and THEICTA crosslinkers into formulations with desired loadings of zirconia ranging from 30.6 to 37.1 wt%, monomer weight percentages ranging from 5.9 to 9.8 wt%, crosslinker weight percentages ranging from 2.6 to 8.5 wt%, and TPO photoinitiator weight percentages of 0.5 wt% (see Methods for Making Solventless or Solvent-Containing Formulations). Representative formulations of Example 1 are labeled as Formulations A1 to A5 according to Table 1 along with their viscosity values. Table 2 lists the film properties including transparency, color, and film RI (589 nm) along with film thickness after thermal baking and UV curing steps of nanocomposites derived from Formulations A1 to A5. These data show clear films with low turbidity at film thicknesses of 700-830 nm and film RI values ​​between 1.70-1.80. Since thermal baking conditions can affect the final film properties, examples A4-1, A4-2, A5-1 and A5-2 are included to show the difference after 2 minutes at 135C (-1s) and 200C (-2s). Figure 2 shows SEM images of formulations A1 and A2 nanoimprinted by NIL technique. Figure 2 shows nanoimprinted tilted structures with 300 nm features and an aspect ratio (for the width of the structure to the height of the tilted structure) of 1.

[0138] [Table 1]

[0139] [Table 2]

[0140] Example 2 (solvent-free ZrO2) The capped ZrO2 nanocrystals in "Example Capped ZrO2 Nanocrystals" were prepared by a solvent extraction process starting with well-dispersed ZrO2 in a low boiling solvent such as ethyl acetate (ETA) and combined with the desired monomers. The monomers include BPMA and PTEA along with BMTPS and THEICTA crosslinkers in a formulation with the desired loading of zirconia ranging from 60.4 to 70.0 wt%, monomer weight percentage ranging from 15.4 to 26.7 wt%, crosslinker weight percentage ranging from 8.2 to 13.7 wt%, and TPO photoinitiator weight percentage of 1.0 wt%. Representative formulations of Example 2 are labeled as Formulations B1 and B2 according to Table 3 along with their viscosity values. Table 4 lists the film properties including transparency, color, and film RI (589 nm) along with film thickness after UV curing process of nanocomposites derived from Formulations B1-B2. These data show formulations that are nanoimprintable, have low viscosity (<2,000 cP), low turbidity at film thicknesses between 6 and 13 microns, and provide clear films with film RI values ​​between 1.70 and 1.73. Figure 3 shows SEM images and corresponding analysis of nanoimprinted structures of formulations B1 and B2 measured by Morphotonics. The images shown in Figure 3a are of triangular, rectangular, and cylindrical lattices of B1 with heights of approximately 700, 560, and 670 nm, respectively. The fidelity of the structures of B1, as depicted by the difference in dimensions between the master and the imprint, is shown in Figure 3b. Figure 3c displays a similar SEM image of B2 with triangular and cylindrical lattices with heights of approximately 600 and 650 nm, respectively.

[0141] [Table 3]

[0142] [Table 4]

[0143] Example 3 (solvent TiO2) The above capped TiO2 nanocrystals in "Example Capped TiO2 Nanocrystals" were prepared by incorporating desired monomers such as BPMA, PTEA and PBA in combination with BMTPS, TMPTA, HR6042 and THEICTA crosslinkers into formulations with desired loadings of titania ranging from 11.6 to 75.0 wt%, monomer weight percentages ranging from 4.2 to 13.6 wt%, crosslinker weight percentages ranging from 2.6 to 7.2 wt%, and TPO photoinitiator weight percentages of 0.5 wt%. Representative formulations of Example 3 are labeled as Formulations C1 to C17 according to Tables 5 to 7 along with their viscosity values. Tables 8 to 10 display film properties including transparency, color, and film RI (589 nm) along with film thickness after thermal baking and UV curing steps of nanocomposites derived from Formulations C1 to C21. These data show clear films with low turbidity at film thicknesses of 0.66 to 2.21 microns and film RI values ​​between 1.80 and 1.91. Table 11 gives the measured nanoindentation data for most of the films. Figure 4 shows SEM images of nanoimprints of formulations C1, C2 and C3 measured by NIL technique. The binary grating of C1 is shown in the SEM micrograph with structure height and width of approximately 300 and 400 nm, respectively. In addition, tilted gratings of C1, C2 and C3 with 300 nm features and aspect ratio (for structure width to tilted structure height) of 1 are displayed in Figure 4.

[0144] [Table 5]

[0145] [Table 6]

[0146] [Table 7]

[0147] [Table 8]

[0148] [Table 9]

[0149] [Table 10]

[0150] [Table 11]

[0151] Example 4 (solvent-free TiO2) The capped TiO2 nanocrystals in "Example Capped TiO2 Nanocrystals" were prepared by a solvent extraction process starting with TiO2 well dispersed in a low boiling solvent such as ethyl acetate (ETA) and combined with the desired monomers. The monomers include BPMA, PTEA and PBA with THEICTA crosslinker in formulations with desired loadings of titania ranging from 60.5 to 73.0 wt%, monomer weight percentages ranging from 16.9 to 29.4 wt%, crosslinker weight percentages ranging from 9.1 to 10.1 wt%, and TPO photoinitiator weight percentages of 1.0 wt%. Representative formulations of Example 4 are labeled as Formulations D1-D4 according to Table 12 along with their viscosity values. Table 13 lists the film properties including transparency, color and film RI (589 nm) along with film thickness after thermal baking and UV curing steps of nanocomposites derived from Formulations D1-D4. These data show formulations that are nanoimprintable, have low viscosity (≦2,000 cP), and give clear films with low turbidity at film thicknesses between 10-12 microns and film RI values ​​between 1.86-1.87. Figure 5 shows SEM images of nanoimprinted structures of formulations D1 and D2 and the corresponding analysis measured by Morphotonics. Figures 5a and 5b show triangular and cylindrical imprinted structures with approximately 300 nm width and between 535-757 nm (height).

[0152] [Table 12]

[0153] [Table 13]

[0154] Example 5 (Inkjet printable solvent-free ZrO2) The capped ZrO2 nanocrystals described above in "Example Capped ZrO2 Nanocrystals" were prepared by a solvent extraction process starting with ZrO2 well dispersed in a low boiling solvent such as ethyl acetate (ETA) and combined with the desired monomer, or ZrO2 was directly dispersed in the desired monomer. The monomer includes 2-PEA, BAC, BPMA, HDDA, NVP along with THEICTA crosslinker, photoinitiator I819 and ITX, photosynergist CN374 and BYK surfactant in a formulation with the desired loading of zirconia ranging from 35-45 wt%, the weight percentage of monomer ranging from 46.0-56.0 wt%, the weight percentage of crosslinker ranging from 0.0-10.0 wt%, and the weight percentage of photoinitiator between 1.0-3.0 wt%, and the weight percentage of synergist CN374 was 3.0 wt%. Representative formulations from Example 5 are labeled as Formulations E1-E5 according to Table 14 along with their viscosity values. Table 15 lists film properties including clarity, color, and film RI (589 nm) along with film thickness after UV curing process for nanocomposites derived from Formulations E1-E5. These data show formulations that are inkjet printable at print head temperatures above 30° C., have low viscosity (≦25 cP) at 25° C., and give clear films with low turbidity at film thicknesses between 9-13 microns and film RI values ​​between 1.62-1.65.

[0155] [Table 14]

[0156] [Table 15]

[0157] Example 6 (Inkjet printable solvent-free TiO2) The capped TiO2 nanocrystals described above in "Example Capped TiO2 Nanocrystals" were prepared by a solvent extraction process starting with TiO2 well dispersed in a low boiling solvent such as ethyl acetate (ETA) and combined with the desired monomer, or TiO2 directly dispersed in the desired monomer. The monomers include 2-PEA, BAC, BPMA, HDDA along with THEICTA crosslinker, photoinitiator I819 and BYK surfactant in a formulation with the desired loading of titania ranging from 40-50 wt%, monomer weight percentage ranging from 46.5-56.5 wt%, crosslinker weight percentage 4.0 wt%, photoinitiator weight percentage 3.0 wt%, and BYK surfactant 0.5 wt%. Representative formulations of Example 6 are labeled as Formulations F1 and F2 according to Table 16 along with their viscosity values. Table 17 lists the film properties including clarity, color and film RI (589 nm) along with the film thickness after UV curing process of nanocomposites derived from Formulations F1 and F2. These data show formulations that are inkjet printable at print head temperatures above 30° C., have low viscosity (≦25 cP) at 25° C., and give clear films with low turbidity at film thicknesses between 9-12 microns and film RI values ​​between 1.69-1.71.

[0158] [Table 16]

[0159] [Table 17]

[0160] As used herein, the singular forms "a," "an," and "the" include plural references unless expressly stated or clear from the context that this is not intended.

[0161] The term "and / or" as used herein in expressions such as "A and / or B" is intended to include both A and B; A or B; A (alone); and B (alone). Similarly, the term "and / or" as used in phrases such as "A, B, and / or C" is intended to encompass each of the following specific examples: A, B, and C; A, B, or C; A or C; A or B; B or C; A and C; A and B; B and C; A (alone); B (alone); and C (alone).

[0162] Headings and subheadings are used for convenience and / or formal compliance only, are not intended to limit the subject art, and should not be referenced in connection with interpreting the description of the subject art. Features described under one heading or one subheading of the subject disclosure may be combined with features described under other headings or subheadings in various embodiments. Moreover, not all features under a single heading or a single subheading may be used together in an embodiment.

[0163] The Abstract and Summary sections are not intended to be in any way limiting of the invention and the appended claims, as they may present one or more exemplary embodiments of the invention contemplated by the inventors, although not all of them.

[0164] The present invention has been described with the aid of functional blocks illustrating implementations of specified functions and relationships thereof. The boundaries of these functional blocks have been arbitrarily defined herein for convenience of description. Alternative boundaries may be defined so long as the specified functions and relationships thereof are appropriately performed.

[0165] For aspects of the invention described as genus, all individual species are considered individually as separate aspects of the invention. When an aspect of the invention is described as "comprising" a certain feature, it is also contemplated that the embodiment "consisting of" or "consisting essentially of" that feature.

[0166] The foregoing description of specific embodiments fully reveals the general nature of the present invention, so that others can easily modify and / or adapt such specific embodiments for various applications by applying knowledge within the ordinary skill of those skilled in the art without undue experimentation and without departing from the general concept of the present invention. Such adaptations and modifications are therefore intended to be within the meaning and range of equivalents of the disclosed embodiments, based on the teaching and guidance presented herein. It should be understood that the terms or phrases herein are for the purpose of description and not for the purpose of limitation, as they should be interpreted by those skilled in the art in light of the teaching and guidance.

[0167] The breadth and scope of the present invention should not be limited by any of the above-described exemplary embodiments. All of the various aspects, embodiments, and options described herein can be combined in any and all variations.

[0168] All publications, patents, and patent applications mentioned in this specification are incorporated by reference herein to the same extent as if each individual publication, patent, or patent application was specifically and individually indicated to be incorporated by reference. In the event that a meaning or definition of a term in this specification conflicts with a meaning or definition of the same term in a document incorporated by reference, the meaning or definition assigned to that term in this specification shall control.

Claims

1. 1. A nanoimprintable formulation comprising at least partially capped metal oxide nanocrystals in a matrix comprising at least one monomer, oligomer, or polymer, 1. A nanoimprintable formulation, wherein the formulation has a %T greater than 50% and a refractive index between 1.6 and 2.1, and is formulated to be suitable for the preparation of optically transparent nanocomposites, and wherein the formulation is nanoimprintable to produce nanoimprinted structures on the order of 10 to 1000 nm.

2. 10. The nanoimprintable formulation of claim 1, wherein the at least partially capped metal oxide nanocrystals have an average particle size in the range of 1 to 100 nm as measured by TEM or DLS.

3. 3. The nanoimprintable formulation of claim 1 or 2, wherein the metal oxide is selected from zirconium oxide, titanium oxide, hafnium oxide, zinc oxide, tantalum oxide, niobium oxide, and combinations thereof, preferably the metal oxide is zirconium oxide or titanium oxide.

4. The at least partially capped metal oxide nanocrystals may be selected from the group consisting of methyltrimethoxysilane, n-propyltrimethoxysilane, n-propyltriethoxysilane, n-octyltrimethoxysilane, n-octyltriethoxysilane, phenyltrimethoxysilane, dodecyltrimethoxysilane, m,p-Ethylphenethyltrimethoxysilane, 2-[methoxy(polyethyleneoxy)propyl]trimethoxysilane, methoxy(triethyleneoxy)propyltrimethoxysilane, 3-aminopropyltrimethoxysilane, 3-mercaptopropyltrimethoxysilane, 3-(methacryloyloxy)propyltrimethoxysilane, 3-(acryloyloxy)propyltrimethoxysilane, 3-isocyanatopropyltriethoxysilane, 3-isocyanatopropyltrimethoxysilane, 3-glycidoxypropyltrimethoxysilane, vinyltrimethoxysilane, allyltrimethoxysilane, 1-hexynyltrimethoxysilane, 1-octenyltrimethoxysilane, (phenylaminomethyl)methyldimethoxysilane, N-phenylaminopropyltrimethoxysilane, 3-(4-pyridylethyl)thiopropyltrimethoxysilane, N-(3-trimethoxysilylpropyl)pyrrole, 2-(3-trimethoxysilylpropylthio)thiophene, (3-trimethoxysilylpropyl) (2-diphenylphosphino)diethylenetriamine, 11-mercaptoundecyltrimethoxysilane, (2-diphenylphosphino)ethyldimethylethoxysilane, 2-(diphenylphosphino)ethyltriethoxysilane, 3-(diphenylphosphino)propyltriethoxysilane, heptanol, hexanol, octanol, benzyl alcohol, phenol, ethanol, propanol, butanol, oleyl alcohol, dodecyl alcohol, octadecanol, triethylene glycol monomethyl ether ter, octanoic acid, acetic acid, propionic acid, 2-[2-(2-methoxyethoxy)ethoxy]acetic acid, oleic acid, benzoic acid, stearic acid, trifluoroacetic acid, biphenyl-4-carboxylic acid, 2-(2-methoxyethoxy)acetic acid, methacrylic acid, mono-2-(methacryloyloxy)ethylsuccinic acid, 2-mercaptoethanol, 2-{2-[2-(2-mercaptoethoxy)ethoxy)ethoxy]ethoxy}ethanol, 2-(2-methoxyethoxy)ethanethiol, 1-octanethiol, 2,The nanoimprintable formulation of claim 1 or 2, which is capped with at least one capping agent selected from sodium 3-dimercaptopropane sulfate monohydrate, sodium dodecyl sulfate, dodecylphosphonic acid, octylphosphonic acid, (11-mercaptoundecyl)phosphonic acid, (11-(acryloyloxy)undecyl)phosphonic acid, 11-methacryloyloxyundecylphosphonic acid, [2-[2-(2-methoxyethoxy)ethoxy]ethyl]phosphonic acid ethyl ester, and combinations thereof.

5. The matrix comprises one or more agents independently selected from (1) acrylate and / or methacrylate monomers, e.g., those having mono-, di-, tri-, tetra-, and other multifunctional reactive chemical groups, (2) a reactive diluent, and (3) a curing agent or polymerization initiator. and The nanoimprintable formulation of claim 1 , wherein the matrix optionally comprises a surfactant and / or a wetting agent.

6. 6. The nanoimprintable formulation of claim 5, comprising at least partially capped metal oxide nanocrystals in an amount ranging from 20 to 80% by weight of the total solids of the formulation, or any range or value therebetween.

7. 3. The nanoimprintable formulation of claim 1 or 2, comprising monofunctional acrylate and / or methacrylate monomers with high refractive index such as benzyl acrylate (BA), benzyl methacrylate (BMA), ethylene glycol phenyl ether acrylate (PEA), ethylene glycol phenyl ether methacrylate (PEMA), 2-hydroxy-3-phenoxypropyl acrylate (HPPA), 2-hydroxy-3-phenoxypropyl methacrylate (HPPMA), 2-phenoxybenzyl acrylate (PBA), biphenyl methacrylate (BPMA), 2-phenylphenol methacrylate (PPMA), isobutyl acrylate (IBA), 2-phenylethyl acrylate (2-PEA), 2-(phenylthio)ethyl acrylate (PTEA), or combinations thereof.

8. 1,6-hexanediol diacrylate (HDDA), 1,6-hexanediol dimethacrylate (HDDMA), di(ethylene glycol) diacrylate (DEGDA), di(ethylene glycol) dimethacrylate (DEGDMA), ethylene glycol diacrylate, glycerol 1,3-diglycerolate diacrylate, tri(propylene glycol) diacrylate, trimethylolpropane triacrylate (TMPTA), trimethylolpropane tri-methacrylate (TMPTMA), trimethylolpropane ethoxylate triacrylate (EO 3. The nanoimprintable formulation of claim 1 or 2, comprising di-, tri-, tetra- and / or penta-functional acrylate and / or methacrylate monomers, including trimethylolpropane ethoxylate tri-methacrylate (EOTMPTMA), 1,6-hexanediol ethoxylate diacrylate, tris(2-hydroxyethyl)isocyanurate triacrylate, pentaerythritol tetraacrylate (PETA), dipentaerythritol penta- / hexa-acrylate (DPPA / DPHA), or combinations thereof.

9. 3. The nanoimprintable formulation of claim 1 or 2, comprising a crosslinker, preferably a di-, tri-, and / or tetra-functional thiol crosslinker comprising trimethylolpropane tris(3-mercaptopropionate).

10. 3. A nanoimprintable formulation according to claim 1 or 2, comprising one or more high refractive index and / or sulfur containing monomers and / or resins, wherein said one or more high refractive index and / or sulfur containing monomers are compounds and derivatives thereof having the following structure: 【Chemistry 1-1】 [Chemistry 1-2] The nanoimprintable formulation as described above, comprising a sulfur-containing monomer and / or resin selected from:

11. Contains a reactive diluent, A nanoimprintable formulation according to claim 1 or 2, wherein the weight percentage of said reactive diluent is between 0.1 and 40% by weight, preferably between 1.0 and 10% by weight, relative to the total formulation.

12. comprising one or more agents independently selected from curing agents, surfactants, wetting agents, antioxidants, adhesion promoters, leveling agents, dispersants, plasticizers, toughening agents, thickeners, thinners, dispersants, softeners, organic dopants, and other functional additives; 3. The nanoimprintable formulation of claim 1 or 2, wherein the weight percentage of said drug ranges from 0.1 to 10% by weight relative to the total formulation.

13. The nanoimprintable formulation of claim 1 or 2, wherein the nanoimprinted structures include binary, ramp, sawtooth and other shapes.

14. The nanoimprintable formulation of claim 1 or 2, wherein the nanoimprinted structures have an aspect ratio of 0.5:1 to 10:

1.

15. 3. The nanoimprintable formulation of claim 1 or 2, wherein the formulation comprises a solvent selected from alcohols, glycols, methyl acetate, ethyl acetate, esters, ketones, glycol ethers, glycol esters, such as propylene glycol monomethyl ether acetate (PGMEA), propylene glycol monomethyl ether (PGME), ethylene glycol monobutyl ether acetate, diethylene glycol monobutyl ether acetate, diethylene glycol butyl ether, diethylene glycol monoethyl ether acetate, dipropylene glycol methyl ether acetate, butoxyethanol, butoxypropanol, ethyl ethoxyacetate, ethyl butoxyacetate, 2-(isopentyloxy)ethanol, 2-(hexyloxy)ethanol, diethylene glycol, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, triethylene glycol, triethylene glycol monomethyl ether, dipropylene glycol, dipropylene glycol monomethyl ether, and dipropylene glycol monoethyl ether, ethyl acetate, THF, acetone, and any combination thereof.

16. 3. A nanoimprintable formulation according to claim 1 or 2, wherein the viscosity of the formulation is in the range of 1 to 1000 cP when measured at 25°C using a Brookfield RVDV II+ cone and plate viscometer, which is preferred for depositing films with thicknesses ranging from 100 nm to 20 microns.

17. 3. The nanoimprintable formulation of claim 1 or 2, wherein said formulation is inkjet printable.

18. A nanocomposite made from the nanoimprintable formulation of claim 1.

19. 20. The nanocomposite of claim 18, comprising nanoimprinted structures having binary, ramp, sawtooth and / or other shapes, the nanoprinted structures having height, width and / or pitch on the order of 10-1000 nm.

20. 20. The nanocomposite of claim 18 or 19, comprising nanoimprinted structures having an aspect ratio of 0.5:1 to 10:

1.

21. 20. The nanocomposite of claim 18 or 19, comprising the at least partially capped metal oxide nanocrystals in an amount selected from 35-40%, 40-45%, 45-50%, 50-55%, 55-60%, 60-65%, 65-70%, 70-75%, and 75-80% by weight of the nanocomposite.

22. 1.54-1.56, 1.56-1.58, 1.58-1.60, 1.60-1.62, or 1.62-1.64, 1.64-1.66, or 1.66-1.68, or 1.68-1.70, or 1.70-1.72, or 1.72-1.74, or 1.74-1.76, or 1.76-1.78, or 1.78-1.80, or 1.80-1.82, or 1.82-1.84, or 1.84-1.86 at 589 nm 20. The nanocomposite of claim 18 or 19, having a refractive index in the range of 1.86 to 1.88, or 1.88 to 1.90, or 1.90 to 1.92, or 1.92 to 1.94, or 1.94 to 1.96, or 1.96 to 1.98, or 1.98 to 2.00, or 2.00 to 2.02, or 2.02 to 2.04, or 2.04 to 2.06, or 2.06 to 2.08, or 2.08 to 2.10, or greater than 2.

10.

23. The nanocomposite, cured or partially cured at a thickness of less than 10 microns, has a %T of 99% to 95%, or 95% to 90%, or 90% to 85%, or 85% to 80%, or 80% to 75% in the ultraviolet-A and near-ultraviolet spectrum from 300 to 400 nm, in the visible wavelengths from 400 to 700 nm, and / or in the near-infrared and infrared spectrum from 700 to 1600 nm.

20. The nanocomposite of claim 18 or 19, wherein the % porosity of the nanocomposite is 75% to 70%, or 70% to 65%, or 65% to 60%, or 60% to 55%, or 55% to 50%, or 50% to 45%, or 45% to 40%, or 40% to 35%, or 35% to 30%, or 30% to 25%, or 25% to 20%, or 20% to 15%, or 15% to 10%.

24. 20. Nanocomposite according to claim 18 or 19, characterized in that the hardness measured by nanoindentation is in the range of 1 to 400 MPa.

25. 20. Nanocomposite according to claim 18 or 19, characterized in that it has a Young's modulus measured by nanoindentation in the range of 0.1 to 10 GPa.

26. 20. A device comprising the nanocomposite of claim 18 or 19.

Images