Solvent-free formulations and nanocomposites

Abstract

We provide high refractive index acrylic formulations that are solvent-free, low viscosity, inkjet compatible (particularly for film deposition techniques), and enable the fabrication of high refractive index, high transparency nanocomposites for a variety of optical applications, including OLED lighting and display applications. [Solution] A formulation is provided that includes at least partially capped metal oxide nanocrystals and a matrix containing at least one monomer, oligomer, or polymer, for example, the at least partially capped metal oxide nanocrystals are dispersed in the matrix, and the metal oxide is zirconium oxide, titanium oxide, hafnium oxide, zinc oxide, tantalum oxide, niobium oxide, or a mixture of at least two of the foregoing oxides, and the formulation includes less than 5 wt% solvent.

Description

[Technical Field]

[0001] This application claims priority to U.S. Provisional Application No. 62 / 769,696, filed November 20, 2018, and U.S. Provisional Application No. 62 / 892,610, filed August 28, 2019, the contents of which are incorporated herein by reference in their entireties. [Background technology]

[0002] The solvent-free polymer nanocomposite formulations described herein exhibit low viscosity, high refractive index, and high optical transmittance in the visible spectrum. The materials of the present disclosure are easily applied to the surface of desired substrates for many electronic applications through common solution coating processes, such as inkjet printing, spin coating, screen printing, dipping, dispensing, roll-to-roll, slot die, draw bar, or spray coating. The nanocomposites of the present disclosure are unique in providing films, coatings, or layers with high refractive index and transparency, which are desirable in electronic applications such as organic light-emitting diode (OLED) applications, where these properties are critical to performance. The thickness of the coatings described herein can range from tens of nanometers to millimeters, as required for specific applications.

[0003] OLEDs can be classified as bottom-emitting or top-emitting based on the direction of light output. Bottom-emitting OLEDs are used in large panels such as televisions, while top-emitting OLEDs are used in small mobile device applications. A top-emitting OLED device consists of a reflective layer, an ITO anode, a hole-injection layer (HIL), a hole-transport layer (HTL), an emissive layer (EML), an electron-transport layer (ETL), an electron-injection layer (EIL), a semitransparent metal cathode, and a capping layer on top of a thin-film transistor structure. Light generated from the emissive region passes through the semitransparent metal cathode. Only a small amount of the generated light (approximately 25%) can be extracted from the OLED device due to potential light trapping in surface plasmon modes within the waveguide or stack. In addition, a portion of the light is reflected back into the device through the thin-film encapsulation layers due to refractive index mismatches between these layers. To improve the optical efficiency of this structure, high refractive index (HRI) layers are required to eliminate waveguide trapping modes between inorganic passivation layers and between the thin-film encapsulation layer and other layers. These waveguide trapping modes can only be resolved by using index-matched HRI layers. High refractive index, highly transparent coatings with refractive indices of about 1.7 or greater can be fabricated using the materials disclosed herein, dramatically enhancing the effectiveness of OLED lighting and display devices incorporating them.

[0004] Inkjet printing is a key process in manufacturing OLED devices, including depositing reliable organic passivation and planarization layers. It is also cost-effective and allows for a vacuum-free process. Inkjet printing equipment effectively deposits the intended ink formulation onto a variety of substrates, providing efficient material transfer with little or no waste. Inkjet printing also allows for the rapid deposition of simple films of specific thicknesses or the more complex patterns required for a given application.

[0005] Formulation viscosity is one of the important parameters for determining applicability to inkjet printing. For illustrative purposes, inkjet printing typically requires a value of 5-20 cP at 25°C. Higher viscosities are permissible when printhead heating is utilized. Depending on the heating capacity of the printhead, the viscosity can be as high as 100 cP at 25°C, and at higher temperatures of approximately 60-100°C, the viscosity can be reduced to within the range of 5-20 cP. Reducing formulation viscosity to this narrow range The key monomer, oligomer, and polymer selection and nanoparticle loading must be achieved by carefully considering the properties of the matrix. A low viscosity matrix material with a sufficiently high refractive index allows for sufficient nanoparticle loading to achieve the final desired refractive index of the film. Finding low viscosity, high refractive index monomers, oligomers, and polymers is often a challenge, since these properties generally increase together.

[0006] In addition to formulation viscosity, inks must have a surface tension suitable for stable droplet ejection, as well as sufficient wetting on the desired substrate. Surface tension in inkjet printing typically ranges from 20 to 35 dynes / cm, depending on other fluid properties such as viscosity and density, as well as inkjet parameters such as droplet volume and drop rate. As droplets are ejected from the nozzle, ligaments, or tails, appear and shrink, forming spherical droplets. If the ligaments do not shrink quickly enough or for too long, small satellites can form, potentially causing problems in the printed film. Stable droplet ejection without tails or satellites is important for optimal jetting performance and print uniformity. Additionally, inks should be stable over long periods of time for manufacturability. Shelf life, or time before use, is desirable, and pot life, or time during use, and jetting stability, are desirable, targeting at least one day.

[0007] Other deposition techniques, such as slot die coating, spin coating, drawdown, or screen-printed films and dispensing lenses, are applicable to the formulations disclosed herein. High-viscosity formulations with high nanoparticle loadings and potentially high-viscosity components (e.g., crosslinkers, oligomers, and polymers), as well as high refractive index values, in addition to other physical properties, may be achieved. The relevant range of viscosities suitable for these various deposition techniques may range from 5 to 12,000 cP, or even greater than 12,000 cP.

[0008] The formulations of the present disclosure are preferably solvent-free, but allow for small amounts of solvent to maintain the lower viscosity characteristic of inkjet printing. Formulations can be either "solvent-free" or "solvent-free" under the disclosed invention. A "solvent-free" formulation contains less than 5 wt% solvent, or between 0 and 5 wt%, preferably between 0 and 1 wt%, of the total formulation. A "solvent-free" formulation contains between 5 and 20 wt% solvent, of the total formulation.

[0009] Solvent-free formulations are most desirable for OLED applications due to the need to minimize outgassing of organic species from cured layers. Outgassing of volatile organics can cause problems within the multilayer structure of OLED display devices, leading to device failure over time during processing steps (e.g., indium-tin oxide (ITO) deposition) or device operation. Traditionally, solvent-borne materials have been used to deposit polymer films via solution processes, such as inkjet printing, spin coating, screen printing, dipping, dispensing, roll-to-roll, slot-die, draw bar, and spray coating. In electronic devices, including OLEDs, solvent-borne materials have also been used for electrical and optical components. However, these solvent-borne materials adversely affect device performance and processing, even when the solvent is removed by post-deposition thermal treatment. One of the major degradation issues in organic devices is residual solvent in the applied film, which reduces device efficiency and lifetime. To mitigate these and other issues and eliminate costly and time-consuming processes such as vacuum chamber drying, solvent-free, solution-processable materials are being developed. Additionally, a solvent-free formulation would reduce the number of processing steps (pre-baking and post-baking) required to cure the film before depositing the next layer in the device. Ideally, a solvent-free UV-curable formulation would allow for fast and easy curing of the film after deposition.

[0010] The refractive index of the solvent-free formulation is designed to match or closely match the refractive index of the adjacent layer. The refractive index of the nanocomposite layer is preferably 1.6-2.0, corresponding to the refractive index (1.8-2.1) of inorganic layers such as ITO and silicon nitride at visible wavelengths. High-refractive-index inorganic oxides, such as zirconium oxide, titanium oxide, hafnium oxide, zinc oxide, tantalum oxide, and niobium oxide nanocrystals, can achieve values ​​in this specified range. When synthesized below 40 nm and capped with a capping agent suitable for dispersibility, the capped metal oxides can be dispersed in appropriate monomers, oligomers, and polymers at loadings of 35-90% to produce stable dispersions capable of producing films with refractive index values ​​ranging from 1.6 to 2.0 across the visible light range. Inorganic oxides with even lower refractive indices, such as silicon dioxide and germanium oxide, either cannot achieve values ​​in the desired range or require very high loadings to ultimately achieve the desired high refractive index. Additionally, high nanoparticle loadings typically result in very high viscosities that preclude certain formulations from being suitable for specific deposition processes such as inkjet printing.

[0011] Nanocomposite formulations intended for use as high-refractive-index or index-matching materials in smart windows, sensors, CMOS sensors, LEDs, mini-LEDs, micro-LEDs, organic LEDs (OLEDs), quantum LEDs (QLEDs), touchscreens, displays, flexible electronics, printed electronics, self-cleaning surfaces, augmented reality (AR), mixed reality (MR), virtual reality (VR), waveguides, light extraction, and 3D sensors. The transparency of formulations and films is strongly related to the size and distribution of nanoparticles. By synthesizing and maintaining particle sizes below 40 nm, formulations and films enable high light transmittance (>95%) across the visible spectrum. Particles larger than 40 nm tend to scatter light, resulting in an overall decrease in the transmittance of the material. Furthermore, agglomerated particles can cause this scattering issue if the dispersion is not stable over the long term. Unstable dispersions are likely to have particles that are not adequately capped with sufficient or appropriate capping agents for the intended organic matrix. Additionally, the small particle size and narrow size distribution, combined with the absence of aggregates in the formulation, allows for high nanocrystal loadings without significantly increasing viscosity, resulting in formulations with high refractive index, high clarity, and low viscosity.

[0012] Finally, high-RI ink formulations designed for inkjet printing must have stable jetting properties over long periods of time for high-productivity applications. The components in the ink must have low volatility to prevent residue in the inkjet nozzles from significantly increasing viscosity. This can lead to nozzle clogging and defects in the printed film, such as streaks and pinholes. Inks with this problem may require constant use or frequent purging of the printhead to prevent clogging. Industry demands periods of no jetting, ranging from minutes to hours, or even days in extreme cases. Summary of the Invention

[0013] The present disclosure provides solvent-free, low-viscosity, high-refractive-index, UV-curable formulations comprising metal oxide nanocrystals capped in an organic matrix with a curing agent. The formulations further comprise any of the following ingredients: wetting agents, antioxidants, adhesion promoters, leveling agents, dispersing agents, plasticizers, tougheners, thickeners, diluents, dispersants, or softeners, or organic dopants or other functional additives. These formulations result in nanocomposites with high refractive index and transparency.

[0014] The present disclosure provides the following non-limiting numbered embodiments as further examples of the disclosed technology: 1. A dispersion of at least partially capped metal oxide nanocrystals and at least and a matrix comprising one monomer, oligomer, or polymer, optionally further comprising a curing agent, a surfactant, a wetting agent, an antioxidant, an adhesion promoter, a leveling agent, a dispersing agent, a plasticizer, a toughener, a thickener, a diluent, a dispersant, or a softener, or an organic dopant, or other functional additive. 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. 3. The formulation of embodiments 1-2, wherein the metal oxide nanocrystals are zirconium oxide, titanium oxide, hafnium oxide, zinc oxide, tantalum oxide, niobium oxide, or a mixture of at least two of the oxides. 4. A formulation described in any one of embodiments 1-2, wherein the average particle size of the at least partially capped nanocrystals is in the range of 1 to 30 nm, preferably less than 20 nm, as measured by DLS or TEM. 5. The nanocrystals are selected from the group consisting of methyltrimethoxysilane, n-propyltrimethoxysilane, n-propyltriethoxysilane, n-octyltrimethoxysilane, n-octyltriethoxysilane, phenyltrimethoxysilane, dodecyltrimethoxysilane, m,p-ethylphenyltrimethoxysilane, 2-[methoxy(polyethyleneoxy)propyl]trimethoxysilane, methoxy(triethyleneoxy)propyltrimethoxysilane, 3-aminopropyltrimethoxysilane, 3-mercaptopropyltrimethoxysilane, 3-(methacryloyloxy)propyltrimethoxysilane, 3-(acryloyloxy)propyltrimethoxysilane, 3-isocyanatopropyltriethoxysilane, 3-isocyanatopropyltrimethoxysilane, and glycidoxypropyltrimethoxysilane, vinyltrimethoxysilane, methyltrimethoxysilane, n-propyltriethoxysilane, n-octyltriethoxysilane, phenyltrimethoxysilane, dodecyltrimethoxysilane, m,p-ethylphenyltrimethoxysilane, 2-[methoxy(polyethyleneoxy)propyl]trimethoxysilane, methoxy(triethyleneoxy)propyltrimethoxysilane, 3-aminopropyltrimethoxysilane, 3-mercaptopropyltrimethoxysilane, 3-(methacryloyloxy)propyltrimethoxysilane, 3-(acryloyloxy)propyltrimethoxysilane, 3-isocyanatopropyltriethoxysilane, 3-isocyanatopropyltrimethoxysilane, and glycidoxypropyltrimethoxysilane. 5. The formulation of embodiments 1-4, at least partially capped with at least one capping agent selected from the group consisting of silane, allyltrimethoxysilane, 1-hexenyltrimethoxysilane, 1-octenyltrimethoxysilane, heptanol, hexanol, octanol, benzyl alcohol, phenol, ethanol, propanol, butanol, oleyl alcohol, dodecyl alcohol, octadecanol, triethylene glycol monomethyl ether, 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)ethyl succinate, or any combination thereof. 6. The formulations of embodiments 1-5 include a loading of metal oxide nanocrystals ranging from 20 to 80 wt% of the formulation. 7. The formulation of embodiments 1-6, wherein the metal oxide nanocrystals are at least partially capped, further comprising a high refractive index monofunctional acrylate and / or methacrylate monomer, such as benzyl(meth)acrylate (BA and BMA), ethylene glycol phenyl ether(meth)acrylate (PEA and PEMA), 2-hydroxy-3-phenoxypropyl(meth)acrylate (HPPA and 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 a combination thereof. 8. The formulation of embodiments 1-7, wherein the metal oxide nanocrystals are at least partially capped, and wherein the metal oxide nanocrystals are at least partially capped, and the metal oxide nanocrystals are at least partially capped with di-, tri-, tetra-, and penta-functional acrylate and / or methsylate monomers, such as 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, trimethylol acrylate, ... Formulations further comprising dimethylolpropane tri(meth)acrylate (TMPTA, TMPTMA), trimethylolpropane ethoxylate tri(meth)acrylate (EOTMPTA and EOTMPTMA), 1,6-hexanediol ethoxylate diacrylate, pentaerythritol tetraacrylate (PETA), and dipentaerythritol penta / hexaacrylate (DPHA). 9. The formulation of any one of embodiments 1 to 8, wherein the metal oxide nanocrystals are at least partially capped, further comprising 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 of embodiments 1 to 8 to improve surface hardening or adhesion. The weight percentage of the reactive diluent is 10 to 80 wt% based on the total monomer content. The preferred weight percentage of the reactive diluent is 25 to 70 wt% based on the total monomer content. 10. A formulation according to embodiments 1-9, wherein the metal oxide nanocrystals are at least partially capped, further comprising a di-, tri-, or tetra-functional thiol crosslinker, such as trimethylolpropane tris(3-mercaptopropionate). 11. The formulation of embodiments 1-10, wherein the metal oxide nanocrystals are at least partially capped, further comprising commercially available sulfur-containing resins and adhesives, such as #18109, #18165, and #6205 (NTT-AT); and LumipluS LP-1100, LPB-1102, LPJ-1102, and LPS-1130 (Mitsubishi Gas Chemical Company). 12. The formulation of any one of embodiments 1 to 11, wherein the metal oxide nanocrystals are at least partially capped, further comprising a reactive organic dopant, such as phenanthrene (PhA) or 9-vinylcarbazole (NVCb), wherein the concentration of the organic dopant ranges from 1 to 50 wt %. 13. The formulation of any one of embodiments 1-12, wherein the metal oxide nanocrystals are at least partially capped, further comprising a surfactant or combination of surfactants, such as polyether-modified siloxanes or fluorosurfactants, that are either non-reactive or reactive in acrylate monomer systems. 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%. 14. The formulation of any one of embodiments 1-13, wherein the metal oxide nanocrystals are at least partially capped, and optionally further comprising scattering particles, such as titanium dioxide, aluminum oxide, silicon dioxide, and low and high refractive index polymer particles. The size of the scatterer particles ranges from 100 to 400 nm. The concentration of the scatterer in the total formulation ranges from 0.1 to 30.0 wt%. The preferred concentration of the scattering agent ranges from 0.5 to 17.0 wt%. 15. The formulation of any one of embodiments 1-14, further comprising a curing agent or photoinitiator, such as Irgacure 184, Irgacure 819, TPO, Ebercryl P39, and Ebercryl P115. The concentration of the photoinitiator in the total formulation is in the range of 0.1-20 wt% based on the monomer content. The preferred concentration of the photoinitiator is in the range of 1.0-4.0 wt% based on the monomer content. 16. A formulation described in any one of embodiments 1 to 15, wherein the dispersion does not contain benzyl methacrylate (BMA) or trimethylolpropane triacrylate (TMPTA). 17. A formulation described in any one of embodiments 1 to 16, wherein the formulation is solvent-free or solvent-free. 18. The viscosity of the formulation is The solvent-free and / or solvent-free formulation of embodiment 17, having a viscosity in the range of 5 to 100 cP when measured at 25°C using a 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 is 15 to 100 cP when the cartridge temperature is 35 to 100°C. Alternatively, the viscosity of the formulation 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 when measured at 25°C. For deposition methods other than inkjet printing, the viscosity is in the range of 100 cP to 1,000 cP, 1,000 cP to 5,000 cP, or 5,000 cP to 12,000 cP. 19. The solvent-free and / or solvent-free formulation of any one of embodiments 17-18, wherein the nanocrystal loading is 35-40%, 40-45%, 45-50%, 50-55%, 55-60%, 60-65%, or 65-70% by weight. 20. 20. The solvent-free and / or solvent-free formulation according to any one of embodiments 17-19, wherein the refractive index at 589 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 1.76 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, or 1.90 to 1.92, or 1.92 to 1.94, as measured with an Abbe refractometer. 21. The solvent-free and / or solvent-free formulation of any one of embodiments 17-20, wherein the surface tension of the formulation is within the ranges of 20-25 dynes / cm, 25-30 dynes / cm, 30-35 dynes / cm, and 35-40 dynes / cm, when measured at 25°C using a Rame-Hart surface tensiometer. 22. The solvent-free and / or solvent-free formulation according to any one of embodiments 17-21, wherein the %T of the formulation 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% at visible wavelengths (400-700 nm). 23. The formulation of any one of embodiments 1 to 22, wherein the formulation polarity is at least 4.0-8.0% to ensure little or no wetting of the nozzle plate of an inkjet printhead with a suitable surfactant at a sufficiently high concentration. Similar observations regarding minimum polarity values ​​for good inkjet quality were noted in UK Patent No. GB2517592A (Sericol Ltd, A. Runacre, M. Pemble, G. Osborne, 25.02.2015). Polarity is defined as the ratio of the polar component of the surface tension divided by the total surface tension of the formulation. The polar component of surface tension is determined by measuring the contact angle and surface tension of the formulation on a Teflon substrate using a Lamé-Hart goniometer and tensiometer according to the Owens, Wendt, Rabel, and Kaelble method (see: https: / / www.kruss-scientific.com / services / education-theory / glossary / owens-wendt-rabel-and-kaelble-owrk-method / ). Table 1 displays the contact angle, surface tension, and polarity measurements on a Teflon substrate for various monomers and formulations. 24. The formulations described in embodiments 1 to 23 may be used with Dimatix DMC, Fujifilm SG1024 / MA, They are inkjet printable in that they can be ejected from printhead types such as the Konica Minolta KM1024i, with small droplets at drop velocities of 3-9 m / s and droplet volumes of 6-40 pL. Applications for inkjet printable formulations such as those described in this invention include blanket films, specific patterns, and micron- to millimeter-sized lenses. 25. The formulations of embodiments 1-24 are deposited into a film via spin coating, slot die coating, screen printing, inkjet printing, nanoimprinting, photopatterning, 3D printing, dip coating, draw bar coating, roll-to-roll printing, spray coating, dispensing, volume casting, screen printing, and any combination thereof. [Table 1] 26. A nanocomposite comprising a cured or partially cured formulation according to any one of embodiments 1 to 25, wherein the formulation is cured through UV irradiation under an LED source of UV having wavelengths of 365, 385, 395, and 405 nm. Films obtained from the formulation are UV cured using mercury "D", "H", and "V" lamps. The UV irradiation dose is 0.1 to 10 J / cm. 2 The preferred UV irradiation dose is 0.5 to 2 J / cm 2 UV curing is carried out in air or inert conditions, especially under a nitrogen atmosphere. 27. The nanocomposite of embodiment 26, wherein the film thickness ranges from 50 nanometers to 100 micrometers. Preferred film thickness values ​​range from 0.5 to 20 micrometers. 28. The nanocomposite of any one of embodiments 26-27, wherein the at least 1 μm film has a surface roughness of 5-4 nm, or 4-3 nm, or 3-2 nm, or 2-1 nm, or 1-0.5 nm, or 0.5-0.1 nm. 29. The nanocomposite of any one of embodiments 26-28, wherein the coating or film has high film uniformity (or low film non-uniformity) from edge to center, where film non-uniformity is defined as follows:

number

[0015] In some embodiments, the present disclosure provides a solvent-free or solvent-free nanocomposite formulation comprising metal oxide nanocrystals, such as zirconium oxide, titanium oxide, hafnium oxide, zinc oxide, tantalum oxide, niobium oxide, or a mixture of at least two of said oxides; wherein the at least partially capped nanocrystals have an average particle size in the range of 1 to 40 nm; and wherein said nanocrystals are selected from the group consisting of methyltrimethoxysilane, n-propyltrimethoxysilane, n-propyltriethoxysilane, n-octyltrimethoxysilane, n-octyltriethoxysilane, phenyltrimethoxysilane, dodecyltrimethoxysilane, m,p-ethylphenyltrimethoxysilane, 2-[methoxy(polyethyleneoxy)propyl]trimethoxysilane, methoxy(triethyleneoxy)propyltrimethoxysilane, 3-aminopropyltrimethoxysilane, 3-mercaptopropyltrimethoxysilane, 3-(methacryloyloxy)propyltrimethoxysilane, 3-(acryloyloxy)propyltrimethoxysilane, 3-(meth ... and at least partially capped with at least one capping agent selected from the group consisting of propyltrimethoxysilane, 3-isocyanatopropyltriethoxysilane, 3-isocyanatopropyltrimethoxysilane, and glycidoxypropyltrimethoxysilane, vinyltrimethoxysilane, allyltrimethoxysilane, 1-hexenyltrimethoxysilane, 1-octenyltrimethoxysilane, heptanol, hexanol, octanol, benzyl alcohol, phenol, ethanol, propanol, butanol, oleyl alcohol, dodecyl alcohol, octadecanol, triethylene glycol monomethyl ether, 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)ethyl succinate, or any combination thereof. The formulations consisted 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, HDDMA), di(ethylene glycol) di(meth)acrylate (DEGDA, DEGDMA), ethylene glycol diacrylate, glycerol 1,3-diglycerolate diacrylate, tri(propylene glycol) diacrylate, 1,6-hexanediol ethoxylate diacrylate, ethylene glycol phenyl ether (meth)acrylate (PEA, PEMA), 2-hydroxy-3-phenoxy 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), sulfur-containing commercially available resins and adhesives, e.g., #18109, #18165, and and #6205 (NTT-AT); and Lumiplus LP-1100, LPB-1102, LPJ-1102, LPS-1130 (Mitsubishi Gas Chemical), N-vinylpyrrolidone (NVP), phenylnorbornene, styrene (STY), 4-methylstyrene (4MS), 4-vinylanisole (4VA), divinylbenzene (DVB), trimethylolpropane tri(3-mercaptopropionate) (TMPMP), pentaerythritol tetra(3-mercaptopropionate) (PET The reactive monomers, oligomers, polymers, diluents, and / or organic dopants include ethylene glycol dimercaptopropionate, ethylene glycol dimercaptoacetate, thiodiethanethiol, bis(mercaptoethyl)ether, 2,2'-(ethylenedioxy)diethanethiol, phenanthrene (PhA), 9-cyanophenanthrene, triphenylmethane, benzoquinoline, 9-vinylcarbazole (NVCb), and combinations thereof.The formulations include curing agents and photoinitiators used for photopolymerization and / or thermal polymerization, including Ebecryl® P115, or benzophenone and its derivatives such as Ebecryl® P39, benzophenone, SpeedCure BEM (Lambson USA Ltd., Rutherford, CT, USA), or organic phosphines such as diphenyl(2,4,6-trimethylbenzoyl)-phosphine oxide (TPO), Irgacure 819, or Irgacure 184 (BASF USA, Florham Park, NJ, USA), 2,2-azobis(2-methylpropionitrile) (AIBN), and combinations thereof.The formulations contained BYK-331, BYK-377, and BYK-378 (BYK Chemie, GMBH) and fluorosurfactants such as Novec 4430, Novec 4432, and Novec 4434 (3M, St. Paul, MN, USA), and Capstone FS-3100 (The Chemours Company, Wilmington, DE, USA). Company, Wilmington, DE, USA), BYK-352, BYK-353, BYK-356, BYK-361N, BYK-322, BYK-323, BYK-350 (BYK-Chemie Co., Ltd.), BYK-UV3530, Disper BYK-101 (DISPERBYK-101), Disper BYK-130, Disper BYK-140, Disper BYK-160, Disper BYK-161N, Disper BYK-162N, Disper BYK-163N, Disper BYK-164N, Disper BYK-165N, Disper BYK-166N, Disper BYK-167N, Disper BYK-168N, Disper BYK-169N, Disper BYK-169N, Disper BYK- Surfactants, wetting agents, and leveling agents, including Disper BYK-161, Disper BYK-162, Disper BYK-163, Disper BYK-164, Disper BYK-165, Disper BYK-166, Disper BYK-170, Disper BYK-171, Disper BYK-182, Disper BYK-2000, Disper BYK-2001 (BYK-Chemie GmbH), Solsperse 32000, Solsperse 36000, Solsperse 28000, Solsperse 20000, Solsperse 41000, and Solsperse 45000 (Lubrizol, Wickliffe, OH, USA). The ink contains a dispersing agent, a defoaming agent, and a dispersing agent that promotes efficient inkjet printing.

[0016] In some embodiments, the present disclosure provides a solvent-free or solvent-free nanocomposite formulation comprising metal oxide nanocrystals, such as zirconium oxide, titanium oxide, or a mixture of two of said oxides; the average particle size of the at least partially capped nanocrystals is in the range of about 5-30 nm; and the nanocrystals are at least partially capped with at least one capping agent selected from the group consisting of 3-(methacryloyloxy)propyltrimethoxysilane, 3-(acryloyloxy)propyltrimethoxysilane, and / or methoxy(triethyleneoxy)propyltrimethoxysilane. The formulations include reactive monomers, oligomers, polymers, diluents, and / or organic dopants, including benzyl (meth)acrylate (BA and BMA), trimethylolpropane tri(meth)acrylate (TMPTA and TMPTMA), ethylene glycol phenyl ether (meth)acrylate (PEA and PEMA), 2-phenoxybenzyl acrylate (PBA), biphenyl methacrylate (BPMA), 2-phenylethyl acrylate (2-PEA), 2-(phenylthio)ethyl acrylate (PTEA), N-vinylpyrrolidone (NVP), 4-methylstyrene (4MS), divinylbenzene (DVB), 9-vinylcarbazole (NVCb), and combinations thereof. The formulation includes a curing agent and photoinitiator used for photopolymerization, such as diphenyl(2,4,6-trimethylbenzoyl)phosphine oxide (TPO), Irgacure 819, or Irgacure 184 (BASF USA, Florham Park, NJ, USA), 2,2-azobis(2-methylpropionitrile) (AIBN), and combinations thereof. The formulation includes surfactants, such as BYK-378 and / or BYK-333, wetting agents, leveling agents, defoamers, and dispersants to promote efficient inkjet printing.

[0017] In some embodiments, the present disclosure provides a solvent-free or solvent-free nanocomposite formulation comprising metal oxide nanocrystals, such as zirconium oxide, titanium oxide, or a mixture of two of said oxides; the average particle size of the at least partially capped nanocrystals is in the range of about 10-30 nm; and the nanocrystals are at least partially capped with at least one capping agent selected from the group consisting of 3-(methacryloyloxy)propyltrimethoxysilane, 3-(acryloyloxy)propyltrimethoxysilane, and / or methoxy(triethyleneoxy)propyltrimethoxysilane. The formulations include reactive monomers, oligomers, polymers, diluents, and / or organic dopants, including benzyl (meth)acrylate (BA and BMA), trimethylolpropane tri(meth)acrylate (TMPTA and TMPTMA), ethylene glycol phenyl ether (meth)acrylate (PEA and PEMA), 2-phenoxybenzyl acrylate (PBA), biphenyl methacrylate (BPMA), 2-phenylethyl acrylate (2-PEA), 2-(phenylthio)ethyl acrylate (PTEA), N-vinylpyrrolidone (NVP), 4-methylstyrene (4MS), divinylbenzene (DVB), 9-vinylcarbazole (NVCb), and combinations thereof. The formulation includes a curing agent and photoinitiator used for photopolymerization, such as diphenyl(2,4,6-trimethylbenzoyl)-phosphine oxide (TPO), Irgacure 819, or Irgacure 184 (BASF USA, Florham Park, NJ, USA), 2,2-azobis(2-methylpropionitrile) (AIBN), and combinations thereof. The formulation includes surfactants, wetting agents, leveling agents, defoamers, and dispersants to promote efficient inkjet printing, including BYK-378 and / or BYK-333. The formulation includes an adhesion promoter, such as an organofunctional silane, including 3-aminopropyltriethoxysilane. The formulation includes antioxidants, including butylated hydroxytoluene (BHT), Irganox 1010, Irganox 1076, and SongNox® 1076. agents or oxygen inhibitors.

[0018] In some embodiments, the present disclosure provides a solvent-free nanocomposite formulation comprising metal oxide nanocrystals, such as zirconium oxide, titanium oxide, or a mixture of two of the aforementioned oxides; the at least partially capped nanocrystals have an average particle size in the range of about 10-30 nm; and the nanocrystals are at least partially capped with at least one capping agent selected from the group consisting of 3-(methacryloyloxy)propyltrimethoxysilane, 3-(acryloyloxy)propyltrimethoxysilane, and / or methoxy(triethyleneoxy)propyltrimethoxysilane. The loading of the described capped nanocrystals is 20-80 wt%. The formulations include reactive monomers, oligomers, polymers, diluents, and / or organic dopants, including benzyl (meth)acrylate (BA and BMA), trimethylolpropane tri(meth)acrylate (TMPTA and TMPTMA), ethylene glycol phenyl ether (meth)acrylate (PEA and PEMA), 2-phenoxybenzyl acrylate (PBA), biphenyl methacrylate (BPMA), 2-phenylethyl acrylate (2-PEA), 2-(phenylthio)ethyl acrylate (PTEA), N-vinylpyrrolidone (NVP), 4-methylstyrene (4MS), divinylbenzene (DVB), 9-vinylcarbazole (NVCb), and combinations thereof. The loading of the reactive monomers described ranges from 20 to 80 wt%. The formulation contains a curing agent and photoinitiator used for photopolymerization, including diphenyl(2,4,6-trimethylbenzoyl)phosphine oxide (TPO), Irgacure 819, or Irgacure 184 (BASF USA, Florham Park, NJ, USA), 2,2-azobis(2-methylpropionitrile) (AIBN), and combinations thereof. The formulation contains 0.1 to 20.0 wt% of the curing agent or photoinitiator. The formulation contains BYK-378 and / or BYK-333, a surfactant, a wetting agent, a leveling agent, a defoamer, and a dispersant to promote efficient inkjet printing. The formulation contains 0.1 to 2.0 wt% of the surfactant.

[0019] In some embodiments, the present disclosure provides inkjet-printable, solvent-free nanocomposite formulations comprising metal oxide nanocrystals, such as zirconium oxide, titanium oxide, or a mixture of two of the aforementioned oxides; the at least partially capped nanocrystals have an average particle size in the range of about 10-30 nm; and the nanocrystals are at least partially capped with at least one capping agent selected from the group consisting of 3-(methacryloyloxy)propyltrimethoxysilane, 3-(acryloyloxy)propyltrimethoxysilane, and / or methoxy(triethyleneoxy)propyltrimethoxysilane. The loading of the described capped nanocrystals is 35-70 wt%. The formulations include reactive monomers, oligomers, polymers, diluents, and / or organic dopants, including benzyl (meth)acrylate (BA and BMA), trimethylolpropane tri(meth)acrylate (TMPTA and TMPTMA), ethylene glycol phenyl ether (meth)acrylate (PEA and PEMA), 2-phenoxybenzyl acrylate (PBA), biphenyl methacrylate (BPMA), 2-phenylethyl acrylate (2-PEA), 2-(phenylthio)ethyl acrylate (PTEA), N-vinylpyrrolidone (NVP), 4-methylstyrene (4MS), divinylbenzene (DVB), 9-vinylcarbazole (NVCb), and combinations thereof. The loading of the reactive monomers described ranges from 30 to 65 wt%. The formulation contains curing agents and photoinitiators used for photopolymerization, including diphenyl(2,4,6-trimethylbenzoyl)-phosphine oxide (TPO), Irgacure 819, or Irgacure 184 (BASF USA, Florham Park, NJ, USA), 2,2-azobis(2-methylpropionitrile) (AIBN), and combinations thereof. The loading of the curing agent or photoinitiator is 0.1 to 3.0 wt%. The formulation contains B The ink contains surfactants, wetting agents, leveling agents, defoamers, and dispersants, including YK-378 and / or BYK-333, to promote efficient inkjet printing. The surfactants are present in amounts of 0.1 to 1.0 wt%.

[0020] In some embodiments, the present disclosure provides inkjet-printable, solvent-free nanocomposite formulations comprising metal oxide nanocrystals, such as zirconium oxide, titanium oxide, or a mixture of two of the aforementioned oxides; the at least partially capped nanocrystals have an average particle size in the range of about 10-30 nm; and the nanocrystals are at least partially capped with at least one capping agent selected from the group consisting of 3-(methacryloyloxy)propyltrimethoxysilane, 3-(acryloyloxy)propyltrimethoxysilane, and / or methoxy(triethyleneoxy)propyltrimethoxysilane. The loading of the described capped nanocrystals is 35-70 wt%. The formulations include reactive monomers, oligomers, polymers, diluents, and / or organic dopants, including benzyl (meth)acrylate (BA and BMA), trimethylolpropane tri(meth)acrylate (TMPTA and TMPTMA), ethylene glycol phenyl ether (meth)acrylate (PEA and PEMA), 2-phenoxybenzyl acrylate (PBA), biphenyl methacrylate (BPMA), 2-phenylethyl acrylate (2-PEA), 2-(phenylthio)ethyl acrylate (PTEA), N-vinylpyrrolidone (NVP), 4-methylstyrene (4MS), divinylbenzene (DVB), 9-vinylcarbazole (NVCb), and combinations thereof. The loading of the reactive monomers described ranges from 30 to 65 wt%. The formulation contains a curing agent and photoinitiator used for photopolymerization, including diphenyl(2,4,6-trimethylbenzoyl)phosphine oxide (TPO), Irgacure 819, or Irgacure 184 (BASF USA, Florham Park, NJ, USA), 2,2-azobis(2-methylpropionitrile) (AIBN), and combinations thereof. The formulation contains 0.1-3.0 wt% of the curing agent or photoinitiator. The formulation contains BYK-378 and / or BYK-333, a surfactant, a wetting agent, a leveling agent, a defoamer, and a dispersant to promote efficient inkjet printing. The formulation contains 0.1-1.0 wt% of the surfactant.The formulation viscosity ranges from 6 to 80 cP at 25° C. The formulation RI values ​​at 589 nm range from 1.50 to 1.80, or 1.58 to 1.7.

[0021] In some embodiments, the present disclosure provides a higher viscosity, solvent-free or solvent-free nanocomposite formulation comprising metal oxide nanocrystals, such as zirconium oxide, titanium oxide, or a mixture of two of the aforementioned oxides; the at least partially capped nanocrystals have an average particle size in the range of about 10-30 nm; and the nanocrystals are at least partially capped with at least one capping agent selected from the group consisting of 3-(methacryloyloxy)propyltrimethoxysilane, 3-(acryloyloxy)propyltrimethoxysilane, and / or methoxy(triethyleneoxy)propyltrimethoxysilane. The loading of the described capped nanocrystals is 60-80 wt%. The formulations include reactive monomers, oligomers, polymers, diluents, and / or organic dopants, including benzyl (meth)acrylate (BA and BMA), trimethylolpropane tri(meth)acrylate (TMPTA and TMPTMA), ethylene glycol phenyl ether (meth)acrylate (PEA and PEMA), 2-phenoxybenzyl acrylate (PBA), biphenyl methacrylate (BPMA), 2-phenylethyl acrylate (2-PEA), 2-(phenylthio)ethyl acrylate (PTEA), N-vinylpyrrolidone (NVP), 4-methylstyrene (4MS), divinylbenzene (DVB), 9-vinylcarbazole (NVCb), and combinations thereof. The loading of the reactive monomers described ranges from 20 to 40 wt%. The formulation is diphenyl(2,4,6-trimethylbenzoyl)-phosphine oxide (TPO), Irgacure 819 The formulation contains a curing agent and photoinitiator used for photopolymerization, including BYK-378 (BASF USA, Florham Park, NJ, USA), Irgacure 184 (BASF USA, Florham Park, NJ, USA), 2,2-azobis(2-methylpropionitrile) (AIBN), and combinations thereof. The formulation contains 0.1-3.0 wt% of the curing agent or photoinitiator. The formulation contains BYK-378 and / or BYK-333, a surfactant, a wetting agent, a leveling agent, a defoamer, and a dispersant to promote efficient inkjet printing. The formulation contains 0.1-1.0 wt% of the surfactant. The formulation viscosity ranges from 80 to 12,000 cP at 25°C. The formulation RI value at 589 nm ranges from 1.50 to 1.80, or from 1.58 to 1.7. Nanocomposite

[0022] In some embodiments, the present disclosure provides nanocomposites comprising metal oxide nanocrystals, such as zirconium oxide, titanium oxide, hafnium oxide, zinc oxide, tantalum oxide, niobium oxide, or a mixture of at least two of the foregoing oxides; the at least partially capped nanocrystals have an average particle size in the range of 1 to 40 nm; and the nanocrystals are selected from the group consisting of methyltrimethoxysilane, n-propyltrimethoxysilane, n-propyltriethoxysilane, n-octyltrimethoxysilane, n-octyltriethoxysilane, phenyltrimethoxysilane, dodecyltrimethoxysilane, m,p-ethylphenyltrimethoxysilane, 2-[methoxy(polyethyleneoxy)propyl]trimethoxysilane, methoxy(triethyleneoxy)propyltrimethoxysilane, 3-aminopropyltrimethoxysilane, 3-mercaptopropyltrimethoxysilane, 3-(methacryloyloxy)propyltrimethoxysilane, 3-( ... and at least partially capped with at least one capping agent selected from the group consisting of silane, 3-isocyanatopropyltriethoxysilane, 3-isocyanatopropyltrimethoxysilane, and glycidoxypropyltrimethoxysilane, vinyltrimethoxysilane, allyltrimethoxysilane, 1-hexenyltrimethoxysilane, 1-octenyltrimethoxysilane, heptanol, hexanol, octanol, benzyl alcohol, phenol, ethanol, propanol, butanol, oleyl alcohol, dodecyl alcohol, octadecanol, triethylene glycol monomethyl ether, 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)ethyl succinate, or any combination thereof.The formulations include 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, HDDMA), di(ethylene glycol) di(meth)acrylate (DEGDA, DEGDMA), ethylene glycol diacrylate, glycerol 1,3-diglycerolate diacrylate, tri(propylene glycol) diacrylate, 1,6-hexanediol ethoxylate diacrylate, ethylene glycol phenyl ether (meth)acrylate (PEA, PEMA), 2-hydroxy-3-phenoxypropyl acrylate, Poly(hydroxypropyl methacrylate) (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), sulfur-containing commercially available resins and adhesives, such as #18109, #18165, and #6205 (NTT-AT); and Lumiplus LP-1100, LPB-1102, LPJ-1102, LPS-1130 (Mitsubishi Gas Chemical), N-vinylpyrrolidone (NVP), phenylnorbornene, styrene (STY), 4-methylstyrene (4MS), 4-vinylanisole (4VA). Reactive monomers, oligomers, polymers, diluents and / or organic dopants include divinylbenzene (DVB), trimethylolpropane tri(3-mercaptopropionate) (TMPMP), pentaerythritol tetra(3-mercaptopropionate) (PETMP), ethylene glycol dimercaptopropionate, ethylene glycol dimercaptoacetate, thiodiethanethiol, bis(mercaptoethyl)ether, 2,2'-(ethylenedioxy)diethanethiol, phenanthrene (PhA), 9-cyanophenanthrene, triphenylmethane, benzoquinoline, 9-vinylcarbazole (NVCb), and combinations thereof. The formulations include curing agents and photoinitiators used for photopolymerization and / or thermal polymerization, including Ebecryl® P115, or benzophenone and its derivatives such as Ebecryl P39, benzophenone, Speedcure BEM (Lambson USA, Rutherford, Connecticut, USA), or organic phosphines such as diphenyl(2,4,6-trimethylbenzoyl)-phosphine oxide (TPO), Irgacure 819, or Irgacure 184 (BASF USA, Florham Park, New Jersey, USA), 2,2-azobis(2-methylpropionitrile) (AIBN), and combinations thereof.The formulations contained BYK-331, BYK-377, and BYK-378 (BYK Chemie, GMBH) and fluorosurfactants such as Novec 4430, Novec 4432, and Novec 4434 (3M, St. Paul, MN, USA), and Capstone FS-3100 (The Chemours Company, Wilmington, DE, USA). Company, Wilmington, DE, USA), BYK-352, BYK-353, BYK-356, BYK-361N, BYK-322, BYK-323, BYK-350 (BYK-Chemie Co., Ltd.), BYK-UV3530, Disper BYK-101 (DISPERBYK-101), Disper BYK-130, Disper BYK-140, Disper BYK-160, Disper BYK-161N, Disper BYK-162N, Disper BYK-163N, Disper BYK-164N, Disper BYK-165N, Disper BYK-166N, Disper BYK-167N, Disper BYK-168N, Disper BYK-169N, Disper BYK-169N, Disper BYK- Dispersants that promote efficient inkjet printing include surfactants, wetting agents, leveling agents, defoamers, and dispersants, including Disper BYK-161, Disper BYK-162, Disper BYK-163, Disper BYK-164, Disper BYK-165, Disper BYK-166, Disper BYK-170, Disper BYK-171, Disper BYK-182, Disper BYK-2000, Disper BYK-2001 (BYK-Chemie GmbH), Solsperse 32000, Solsperse 36000, Solsperse 28000, Solsperse 20000, Solsperse 41000, and Solsperse 45000 (Lubrizol, Wickliffe, OH, USA).

[0023] In some embodiments, the present disclosure provides nanocomposites comprising metal oxide nanocrystals, such as zirconium oxide, titanium oxide, or a mixture of two of said oxides; the average particle size of the at least partially capped nanocrystals is in the range of about 10-30 nm; and the nanocrystals are at least partially capped with at least one capping agent selected from the group consisting of 3-(methacryloyloxy)propyltrimethoxysilane, 3-(acryloyloxy)propyltrimethoxysilane, and / or methoxy(triethyleneoxy)propyltrimethoxysilane. The formulations include reactive monomers, oligomers, polymers, diluents, and / or organic dopants, including benzyl(meth)acrylate (BA and BMA), trimethylolpropane tri(meth)acrylate (TMPTA and TMPTMA), ethylene glycol phenyl ether (meth)acrylate (PEA and PEMA), 2-phenoxybenzyl acrylate (PBA), biphenyl methacrylate (BPMA), 2-phenylethyl acrylate (2-PEA), 2-(phenylthio)ethyl acrylate (PTEA), N-vinylpyrrolidone (NVP), 4-methylstyrene (4MS), divinylbenzene (DVB), 9-vinylcarbazole (NVCb), and combinations thereof. The formulation contains curing agents and photoinitiators used for photopolymerization, including trimethylbenzoyl)phosphine oxide (TPO), Irgacure 819, or Irgacure 184 (BASF USA, Florham Park, NJ, USA), 2,2-azobis(2-methylpropionitrile) (AIBN), and combinations thereof. The formulation also contains surfactants, wetting agents, leveling agents, defoamers, and dispersants to promote efficient inkjet printing, including BYK-378 and / or BYK-333.

[0024] In some embodiments, the present disclosure provides nanocomposites comprising metal oxide nanocrystals, such as zirconium oxide, titanium oxide, or a mixture of two of said oxides; the average particle size of the at least partially capped nanocrystals is in the range of about 10-30 nm; and the nanocrystals are at least partially capped with at least one capping agent selected from the group consisting of 3-(methacryloyloxy)propyltrimethoxysilane, 3-(acryloyloxy)propyltrimethoxysilane, and / or methoxy(triethyleneoxy)propyltrimethoxysilane. The formulations include reactive monomers, oligomers, polymers, diluents, and / or organic dopants, including benzyl (meth)acrylate (BA and BMA), trimethylolpropane tri(meth)acrylate (TMPTA and TMPTMA), ethylene glycol phenyl ether (meth)acrylate (PEA and PEMA), 2-phenoxybenzyl acrylate (PBA), biphenyl methacrylate (BPMA), 2-phenylethyl acrylate (2-PEA), 2-(phenylthio)ethyl acrylate (PTEA), N-vinylpyrrolidone (NVP), 4-methylstyrene (4MS), divinylbenzene (DVB), 9-vinylcarbazole (NVCb), and combinations thereof. The formulation includes curing agents and photoinitiators used for photopolymerization, including diphenyl(2,4,6-trimethylbenzoyl)phosphine oxide (TPO), Irgacure 819, or Irgacure 184 (BASF USA, Florham Park, NJ, USA), 2,2-azobis(2-methylpropionitrile) (AIBN), and combinations thereof. The formulation includes surfactants, wetting agents, leveling agents, defoamers, and dispersants to promote efficient inkjet printing, including BYK-378 and / or BYK-333. The formulation includes adhesion promoters, such as organofunctional silanes, including 3-aminopropyltriethoxysilane. The formulation includes antioxidants or oxygen inhibitors, including butylated hydroxytoluene (BHT), Irganox 1010, Irganox 1076, and SongNox® 1076.

[0025] In some embodiments, the present disclosure provides nanocomposites comprising metal oxide nanocrystals, such as zirconium oxide, titanium oxide, or a mixture of two of the aforementioned oxides; the at least partially capped nanocrystals have an average particle size in the range of about 10-30 nm; and the nanocrystals are at least partially capped with at least one capping agent selected from the group consisting of 3-(methacryloyloxy)propyltrimethoxysilane, 3-(acryloyloxy)propyltrimethoxysilane, and / or methoxy(triethyleneoxy)propyltrimethoxysilane. The loading of the described capped nanocrystals is 20-80 wt%. The formulations include reactive monomers, oligomers, polymers, diluents, and / or organic dopants, including benzyl (meth)acrylate (BA and BMA), trimethylolpropane tri(meth)acrylate (TMPTA and TMPTMA), ethylene glycol phenyl ether (meth)acrylate (PEA and PEMA), 2-phenoxybenzyl acrylate (PBA), biphenyl methacrylate (BPMA), 2-phenylethyl acrylate (2-PEA), 2-(phenylthio)ethyl acrylate (PTEA), N-vinylpyrrolidone (NVP), 4-methylstyrene (4MS), divinylbenzene (DVB), 9-vinylcarbazole (NVCb), and combinations thereof. The loading of the reactive monomers described is 20-80 wt%. The formulations include diphenyl(2,4,6-trimethylbenzoyl)-phosphine oxide. The formulation includes a curing agent and photoinitiator used for photopolymerization, including TPO (Tin Oxide), Irgacure 819, or Irgacure 184 (BASF USA, Florham Park, NJ, USA), 2,2-azobis(2-methylpropionitrile) (AIBN), and combinations thereof. The formulation contains 0.1 to 20.0 wt% of the curing agent or photoinitiator. The formulation also contains surfactants, wetting agents, leveling agents, defoamers, and dispersants to promote efficient inkjet printing, including BYK-378 and / or BYK-333. The formulation contains 0.1 to 2.0 wt% of the surfactant.

[0026] In some embodiments, the present disclosure provides nanocomposites derived from inkjet-printable, solvent-free or solvent-free nanocomposite formulations comprising metal oxide nanocrystals, such as zirconium oxide, titanium oxide, or a mixture of two of the aforementioned oxides; the at least partially capped nanocrystals have an average particle size in the range of about 10-30 nm; and the nanocrystals are at least partially capped with at least one capping agent selected from the group consisting of 3-(methacryloyloxy)propyltrimethoxysilane, 3-(acryloyloxy)propyltrimethoxysilane, and / or methoxy(triethyleneoxy)propyltrimethoxysilane. The loading of the described capped nanocrystals is 35-70 wt%. The formulations include reactive monomers, oligomers, polymers, diluents, and / or organic dopants, including benzyl (meth)acrylate (BA and BMA), trimethylolpropane tri(meth)acrylate (TMPTA and TMPTMA), ethylene glycol phenyl ether (meth)acrylate (PEA and PEMA), 2-phenoxybenzyl acrylate (PBA), biphenyl methacrylate (BPMA), 2-phenylethyl acrylate (2-PEA), 2-(phenylthio)ethyl acrylate (PTEA), N-vinylpyrrolidone (NVP), 4-methylstyrene (4MS), divinylbenzene (DVB), 9-vinylcarbazole (NVCb), and combinations thereof. The loading of the reactive monomers described ranges from 30 to 65 wt%. The formulation contains a curing agent and photoinitiator used for photopolymerization, including diphenyl(2,4,6-trimethylbenzoyl)phosphine oxide (TPO), Irgacure 819, or Irgacure 184 (BASF USA, Florham Park, NJ, USA), 2,2-azobis(2-methylpropionitrile) (AIBN), and combinations thereof. The formulation contains 0.1-3.0 wt% of the curing agent or photoinitiator. The formulation contains BYK-378 and / or BYK-333, a surfactant, a wetting agent, a leveling agent, a defoamer, and a dispersant to promote efficient inkjet printing. The formulation contains 0.1-1.0 wt% of the surfactant.

[0027] In some embodiments, the present disclosure provides nanocomposites derived from inkjet-printable, solvent-free or solvent-free nanocomposite formulations comprising metal oxide nanocrystals, such as zirconium oxide, titanium oxide, or a mixture of two of the aforementioned oxides; the at least partially capped nanocrystals have an average particle size in the range of about 10-30 nm; and the nanocrystals are at least partially capped with at least one capping agent selected from the group consisting of 3-(methacryloyloxy)propyltrimethoxysilane, 3-(acryloyloxy)propyltrimethoxysilane, and / or methoxy(triethyleneoxy)propyltrimethoxysilane. The loading of the described capped nanocrystals is 35-70 wt%. Formulations include reactive monomers, oligomers, polymers, and diluents, including benzyl (meth)acrylate (BA and BMA), trimethylolpropane tri(meth)acrylate (TMPTA and TMPTMA), ethylene glycol phenyl ether (meth)acrylate (PEA and PEMA), 2-phenoxybenzyl acrylate (PBA), biphenyl methacrylate (BPMA), 2-phenylethyl acrylate (2-PEA), 2-(phenylthio)ethyl acrylate (PTEA), N-vinylpyrrolidone (NVP), 4-methylstyrene (4MS), divinylbenzene (DVB), 9-vinylcarbazole (NVCb), and combinations thereof. The formulation includes a curing agent and / or organic dopant. The loading of the reactive monomer described is 30-65 wt%. The formulation includes a curing agent and photoinitiator used for photopolymerization, including diphenyl(2,4,6-trimethylbenzoyl)-phosphine oxide (TPO), Irgacure 819, or Irgacure 184 (BASF USA, Florham Park, NJ, USA), 2,2-azobis(2-methylpropionitrile) (AIBN), and combinations thereof. The loading of the curing agent or photoinitiator described is 0.1-3.0 wt%. The formulation includes surfactants, wetting agents, leveling agents, defoamers, and dispersants that promote efficient inkjet printing, including BYK-378 and / or BYK-333. The loading of the surfactant described is 0.1-1.0 wt%. The RI value of the nanocomposite film at 550 nm ranges from 1.63 to 1.75. The %T values ​​for nanocomposite films above 400 nm range from 80 to 97% for film thicknesses between 3 and 10 um.

[0028] In some embodiments, the present disclosure provides nanocomposites derived from solvent-free or solvent-free nanocomposite formulations with higher viscosity (80-12,000 cP) containing metal oxide nanocrystals, such as zirconium oxide, titanium oxide, or a mixture of two of the aforementioned oxides; the average particle size of the at least partially capped nanocrystals is in the range of about 10-30 nm; and the nanocrystals are at least partially capped with at least one capping agent selected from the group consisting of 3-(methacryloyloxy)propyltrimethoxysilane, 3-(acryloyloxy)propyltrimethoxysilane, and / or methoxy(triethyleneoxy)propyltrimethoxysilane. The loading of the described capped nanocrystals is 60-80 wt%. The formulations include reactive monomers, oligomers, polymers, diluents, and / or organic dopants, including benzyl (meth)acrylate (BA and BMA), trimethylolpropane tri(meth)acrylate (TMPTA and TMPTMA), ethylene glycol phenyl ether (meth)acrylate (PEA and PEMA), 2-phenoxybenzyl acrylate (PBA), biphenyl methacrylate (BPMA), 2-phenylethyl acrylate (2-PEA), 2-(phenylthio)ethyl acrylate (PTEA), N-vinylpyrrolidone (NVP), 4-methylstyrene (4MS), divinylbenzene (DVB), 9-vinylcarbazole (NVCb), and combinations thereof. The loading of the reactive monomers described ranges from 20 to 40 wt%. The formulation contains curing agents and photoinitiators used for photopolymerization, including diphenyl(2,4,6-trimethylbenzoyl)phosphine oxide (TPO), Irgacure 819, or Irgacure 184 (BASF USA, Florham Park, NJ, USA), 2,2-azobis(2-methylpropionitrile) (AIBN), and combinations thereof. The loading of the curing agent or photoinitiator is 0.1-3.0 wt%. The formulation also contains surfactants, wetting agents, leveling agents, defoamers, and dispersants to promote efficient inkjet printing, including BYK-378 and / or BYK-333.The surfactant loadings described are 0.1-1.0 wt%. The RI values ​​of the nanocomposite films at 550 nm range from 1.75 to 1.90. The %T values ​​of the nanocomposite films above 400 nm range from 80-97% for film thicknesses of 3-10 μm.

[0029] In some embodiments, the present disclosure provides: [1] A formulation comprising at least partially capped metal oxide nanocrystals and a matrix comprising at least one monomer, oligomer, or polymer, e.g., the at least partially capped metal oxide nanocrystals are dispersed in the matrix, and the metal oxide is zirconium oxide, titanium oxide, hafnium oxide, zinc oxide, tantalum oxide, niobium oxide, or a mixture of at least two of the foregoing oxides, and the formulation comprises less than 5 wt. % solvent; [2] Hardeners, surfactants, wetting agents, antioxidants, adhesion promoters, leveling agents, dispersants The formulation of [1], optionally further comprising one or more agents independently selected from dispersing agents, plasticizers, toughening agents, thickeners, diluents, dispersants, softeners, organic dopants, and other functional additives; [3] The formulation of [1], wherein the matrix comprises one or more agents independently selected from acrylate and / or methacrylate monomers, a reactive diluent, a curing agent, and, optionally, at least one surfactant or at least one wetting agent; [4] The formulation according to any one of [1] to [3], wherein the average particle size of the at least partially capped nanocrystals is in the range of 1 to 40 nm, preferably less than 30 nm, as measured by DLS or TEM; [5] The nanocrystals are selected from the group consisting of methyltrimethoxysilane, n-propyltrimethoxysilane, n-propyltriethoxysilane, n-octyltrimethoxysilane, n-octyltriethoxysilane, phenyltrimethoxysilane, dodecyltrimethoxysilane, m,p-ethylphenyltrimethoxysilane, 2-[methoxy(polyethyleneoxy)propyl]trimethoxysilane, methoxy(triethyleneoxy)propyltrimethoxysilane, 3-aminopropyltrimethoxysilane, 3-mercaptopropyltrimethoxysilane, 3-(methacryloyloxy)propyltrimethoxysilane, 3-(acryloyloxy)propyltrimethoxysilane, 3-isocyanatopropyltriethoxysilane, 3-isocyanatopropyltrimethoxysilane, and glycidoxypropyltrimethoxysilane, vinyltrimethoxysilane.

[0023] The formulation of any one of [1] to [4], at least partially capped with at least one capping agent selected from the group consisting of silane, allyltrimethoxysilane, 1-hexenyltrimethoxysilane, 1-octenyltrimethoxysilane, heptanol, hexanol, octanol, benzyl alcohol, phenol, ethanol, propanol, butanol, oleyl alcohol, dodecyl alcohol, octadecanol, triethylene glycol monomethyl ether, 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)ethyl succinate, or a combination thereof; [6] The formulation according to any one of [1] to [5], wherein the amount of metal oxide nanocrystals in the formulation is in the range of 20 wt% to 80 wt%; [7] The formulation according to any one of [1] to [6], further comprising a monofunctional acrylate and / or methacrylate monomer having a high refractive index, such as benzyl acrylate, benzyl methacrylate (BA and BMA), ethylene glycol phenyl ether acrylate, ethylene glycol phenyl ether methacrylate (PEA and PEMA), 2-hydroxy-3-phenoxypropyl acrylate, 2-hydroxy-3-phenoxypropyl methacrylate (HPPA and 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 a combination thereof; [8] Di-, tri-, tetra-, and / or penta-functional acrylate and / or methacrylate monomers, such as 1,6-hexanediol diacrylate, 1,6-hexanediol di-methacrylate (HDDA and HDDMA), di(ethylene glycol) diacrylate, di(ethylene glycol) dimethacrylate (DEGDA and DEGDMA), ethylene glycol diacrylate, glycerol 1,3-diglycerolate diacrylate, tri(propylene glycol) diacrylate, tri(propylene glycol) diacrylate, tri(propylene glycol) diacrylate, trimethylolpropane triacrylate, trimethylolpropane tri-methacrylate (TMPTA and TMPTMA), trimethylolpropane ethoxylate triacrylate, trimethylolpropane ethoxylate tri-methacrylate (EOTMPTA and EOTMPMA), The formulation according to any one of [1] to [7], further comprising 1,6-hexanediol ethoxylate diacrylate, pentaerythritol tetraacrylate (PETA), dipentaerythritol penta / hexaacrylate (DPHA), or a combination thereof; [9] The formulation according to any one of [1] to [8], further comprising a reactive diluent, such as 1-vinyl-2-pyrrolidone (NVP), N-vinylcaprolactam, 2-(2-vinyloxyethoxy)ethyl acrylate, 2-(2-vinyloxyethoxy)ethyl methacrylate, isobutyl acrylate, styrene (STY), 4-methylstyrene (4MS), 4-vinylanisole (4VA), and divinylbenzene (DVB), wherein the weight percentage of the reactive diluent is 25 to 70 wt% based on the total monomer content;

[10] The formulation according to any one of [1] to [9], further comprising a di-, tri-, and / or tetra-functional thiol crosslinker, such as trimethylolpropane tris(3-mercaptopropionate);

[11] The formulation according to any one of [1] to

[10] , further comprising a sulfur-containing resin and / or adhesive, for example, a commercially available sulfur-containing resin and / or adhesive, for example, #18109, #18165, #6205 (NTT-AT), Lumiplus LP-1100, LPB-1102, LPJ-1102, LPS-1130 (Mitsubishi Gas Chemical), or a combination thereof;

[12] The formulation according to any one of [1] to

[11] , further comprising a reactive organic dopant, for example, phenanthrene (PhA) or 9-vinylcarbazole (NVCb), for example, in a concentration range of 1 to 50 wt %;

[13] The formulation according to any one of [1] to

[12] , further comprising a surfactant or a combination of surfactants, such as polyether-modified siloxanes, fluorosurfactants, which are either non-reactive or reactive in acrylate monomer systems, wherein the concentration of the surfactant in the total formulation is in the range of 0.1 to 2.0 wt %, or in the range of 0.5 to 1.0 wt %;

[14] The formulation according to any one of [1] to

[13] , optionally further comprising scattering particles, such as titanium dioxide, aluminum oxide, silicon dioxide, and / or polymer particles of low and high refractive index, wherein the scattering particle size is in the range of 100 to 400 nm, and the concentration of the scattering particles in the total formulation is in the range of 0.1 to 30.0 wt% or 0.5 to 17.0 wt%;

[15] The formulation according to any one of [1] to

[14] , further comprising a curing agent or photoinitiator, such as Irgacure 184, Irgacure 819, TPO, Ebercryl P39, and / or Ebercryl P115, wherein the concentration of the curing agent or photoinitiator in the total formulation is in the range of 0.1 to 20 wt % or 1.0 to 4.0 wt % relative to the monomer content;

[16] The formulation according to any one of [1] to

[15] , which does not contain benzyl methacrylate (BMA) or trimethylolpropane triacrylate (TMPTA);

[17] The viscosity of the formulation is II+) A formulation according to

[16] , wherein the viscosity is in the range of 5 to 100 cP when measured at 25°C using a cone and plate viscometer, and the preferred viscosity for inkjet printing at 25°C is 5 to 20 cP, and if cartridge heating is applicable, the viscosity at 25°C can be 15 to 100 cP when the cartridge temperature is 35 to 100°C, or the viscosity of the formulation 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, and for deposition methods other than inkjet printing, the viscosity can be in the range of 100 cP to 1,000 cP, 1,000 cP to 5,000 cP, or 5,000 cP to 12,000 cP when measured at 25°C;

[18] Nanocrystal loadings of 35-40 wt%, 40-45 wt%, and 45-50 wt% %, 50-55 wt%, 55-60 wt%, 60-65 wt%, or 65-70 wt% of the formulation described in

[17] ;

[19] The formulation according to any one of

[17] to

[18] , wherein the refractive index of the formulation 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 1.76 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, or 1.90 to 1.92, or 1.92 to 1.94 at 589 nm, as measured with an Abbe refractometer;

[20] The formulation according to any one of

[17] to

[19] , wherein the surface tension of the formulation is within the range of 20 to 25 dynes / cm, 25 to 30 dynes / cm, 30 to 35 dynes / cm, or 35 to 40 dynes / cm when measured at 25°C using a Rame-Hart surface tensiometer;

[21] A formulation according to any one of

[17] to

[20] , wherein the %T of the formulation is 99% to 95%, or 95% to 90%, or 90% to 85%, or 85% to 80%, or 80% to 75%, or 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% at visible wavelengths (400 to 700 nm);

[22] The formulation according to any one of [1] to

[21] , which is inkjet printable, for example, in the form of small droplets of the formulation, that can be ejected from a print head type such as Dimatrix DMC, Fujifilm SG1024 / MA, or Konica Minolta KM1024i at a drop speed of 3 to 9 m / s and a small droplet volume of 6 to 40 pL;

[23] A nanocomposite film prepared from a process comprising applying the formulation of any one of [1] to

[22] to a surface by spin coating, slot die coating, screen printing, inkjet printing, nanoimprinting, photopatterning, 3D printing, dip coating, draw bar coating, roll-to-roll printing, spray coating, dispensing, volume casting, screen printing, or any combination thereof, and optionally curing the applied formulation;

[24] A nanocomposite comprising the cured or partially cured formulation according to any one of [1] to

[23] , wherein the formulation is cured or partially cured through UV irradiation under an LED source of UV having a wavelength of 365 nm, 385 nm, 395 nm, or 405 nm, or through a mercury "D", "H", and / or "V" lamp, at a UV dose ranging from 0.1 to 10 J / cm2, or from 0.5 to 2 J / cm2;

[25] The nanocomposite according to

[24] , which is a film having a thickness ranging from 50 nanometers to 100 micrometers, or from 0.5 micrometers to 20 micrometers;

[26] The nanocomposite of any one of

[23] to

[25] , wherein the %T of the cured or partially cured nanocomposite at a thickness of less than 10 microns is 99% to 95%, or 95% to 90%, or 90% to 85%, or 85% to 80%, or 80% to 75%, or 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% at a visible wavelength of 400 nm to 700 nm; or

[27] Cured or partially cured nanocomposites showed densities of 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 1.6 at 550 nm. 2. The nanocomposite according to any one of claims

[23] to

[26] , having a refractive index of 8 to 1.70, or 1.70 to 1.72, or 1.72 to 1.74, 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, 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. [Brief explanation of the drawings]

[0030] [Figure 1] FIG. 1 shows exemplary viscosities at 25° C. versus weight percent of capped zirconia in BA as described in Example 2. [Figure 2] FIG. 2 shows an exemplary refractive index at 550 nm of the cured films as a function of volume percent of capped zirconia in the BA described in Example 2. [Figure 3] FIG. 3 shows exemplary viscosity versus temperature behavior for formulations having different weight percent capped zirconia in the monomer blend with and without surfactant as described in Examples 2 and 3. [Figure 4] Figure 4 has photographs of varying nozzle plate wetting of a Fujifilm Dimatrix DMC cartridge: severe (top), moderate (middle), and little to no wetting (bottom). [Figure 5] FIG. 5 is a TGA curve obtained as a result of heating Nanocomposite D3 as formulated in Example 3B. [Figure 6] FIG. 6 is the optical density (OD) of nanocomposite D3 as formulated in Example 3B. [Figure 7] FIG. 7 displays the refractive index versus wavelength curve for a cured film of nanocomposite D3 described in Example 3B. [Figure 8]FIG. 8 displays the %T versus wavelength curve for a 10 micron cured film of nanocomposite D3 described in Example 3B. [Figure 9] FIG. 9 shows the viscosity at 25° C. versus the weight percent of PGMEA added to nanocomposites F1 and F2 described in Example 5A of different viscosities, illustrating the dilution effect. [Figure 10] Figure 10 shows the viscosity of TiO2 nanocomposite formulations versus weight percent loading for small (10 nm) and large (30 nm) TiO2 nanoparticles in BA and PBA monomers. [Figure 11] Figure 11 displays the liquid RI at 589 nm of TiO2 nanocomposite formulations versus weight percent loading for small (10 nm) and large (30 nm) TiO2 nanoparticles in BA and PBA monomers. [Figure 12] FIG. 12 displays the RI of cured films at 589 nm of TiO2 nanocomposite formulations versus weight percent loading for small (10 nm) and large (30 nm) TiO2 nanoparticles in BA and PBA monomers. [Figure 13A] Figure 13A shows %T versus wavelength for 10 nm TiO2 nanocomposite BA films with thicknesses ranging from 3.5 to 5.7 microns. [Figure 13B] Figure 13B shows %T versus wavelength for 10 nm TiO2 nanocomposite PBA films with thicknesses from 5.4 to 6.4 microns. [Figure 14A] Figure 14A shows %T versus wavelength for 30 nm TiO2 nanocomposite BA films with thicknesses ranging from 3.3 to 6.1 microns. [Figure 14B] Figure 14B shows %T versus wavelength for 30 nm TiO2 nanocomposite PBA films with thicknesses ranging from 4.4 to 5.8 microns. [Figure 15] FIG. 15 has the %T of the inkjet printed film obtained from Example 10, which consisted of about 30 nm of TiO2 and had a film thickness of 12.0 microns.

[0031] Brief description of the table Table 1 shows contact angles and static surface tension values ​​on a Teflon surface at 25°C for various monomers and formulations, as well as the calculated polar and dispersive components of the surface tension, and polarity (defined as the ratio of the polar component of the static surface tension divided by the total static surface tension).

[0032] Table 2 lists nanocomposite formulations A1-A10 with different weight percentages of capped ZrO2 and weight ratios of crosslinker as described in Example 1, and their respective viscosities.

[0033] Table 3 shows the formulations described in Examples 4 and 5 with different weight percent capped ZrO2 and weight ratios of crosslinker, and their respective viscosities.

[0034] Table 4 shows the formulations described in Example 6 with different capped ZrO2 weight percents and weight ratios of monomer and PhA additive, as well as their respective viscosities and film refractive indices.

[0035] Table 5 shows the formulations described in Example 7 with different capped ZrO2 weight percent and monomer weight ratios, and their respective viscosities and film refractive indices.

[0036] Table 6 shows the formulations described in Example 8 with different weight percentages of approximately 10 nm capped TiO2 and weight ratios of BA and PBA monomers, as well as their respective viscosities, formulation RI values ​​at 589 nm, nanocomposite film RI values ​​at 550 nm, film thickness, and %T values ​​at 400 nm and 700 nm.

[0037] Table 7 shows the formulations described in Example 9 with different weight percentages of approximately 30 nm capped TiO2 and weight ratios of BA and PBA monomers, as well as their respective viscosities, formulation RI values ​​at 589 nm, nanocomposite film RI values ​​at 550 nm, film thickness, and %T values ​​at 400 nm and 700 nm.

[0038] Table 8 shows the formulations described in Example 11 with different capped ZrO2, mixed ZrO2 / TiO2 (particle size of approximately 10 nm), and TiO2 only weight percentages and weight ratios of BA and NVP monomers, as well as their respective viscosities and film refractive indices.

[0039] Table 9 shows the formulations with different capped ZrO2, weight percentages of about 30 nm TiO2 and weight ratios of NTT-AT resin, as described in Example 12, and their respective nanocomposite film refractive indices.

[0040] Table 10 shows the formulations with different capped ZrO2, approximately 10 nm TiO2 weight percent and Lumiplus resin weight ratios, and their respective nanocomposite film refractive indexes, as described in Example 13. DETAILED DESCRIPTION OF THE INVENTION

[0041] Characterization In some embodiments, formulations of the present disclosure are analyzed using a TA instrument Q500 thermal gravimetric analyzer (TGA) to determine the inorganic solids content. TGA is performed using nanocrystal dispersions in solvents with boiling points <200°C to determine the organic content of capped nanocrystals. The percent mass at 200°C relative to the initial mass is used to determine the organic content of the capped nanocrystals. The percent organic content (%Org) of a capped nanocrystal is defined as the difference between the mass at 200°C (M200C) and the mass at 700°C (M700C) divided by the percent mass at 200°C.

number

[0042] For nanocomposites or formulations, 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.

number

[0043] The capped nanocrystals of the formulations of the present disclosure comprise less than 10% by weight of the total formulation, or 10-20% by weight of the total formulation, or 20-30% by weight of the total formulation, or 30-40% by weight of the total formulation, or 40-50% by weight of the total formulation, or 50-60% by weight of the total formulation, or 60-70% by weight of the total formulation, or 70-80% by weight of the total formulation, or 80-90% by weight of the total formulation, or 90-93% by weight of the total formulation.

[0044] 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. Normal 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. The forward light includes both the unscattered transmitted light and the forward scattered light. Theoretically, the forward direction is defined as the same direction as the incident light, but due to its finite size, the detector usually collects light within a small solid angle around this direction. Throughout this disclosure, this transmittance is referred to as normal transmittance or simply transmittance. The absorbance of a sample at a given wavelength, i.e., optical density (OD), is defined as follows:

number

[0045] When measuring normal transmittance, measurement artifacts, such as Fresnel reflections from various interfaces and absorption by the cuvette walls, must be accounted for and removed. This can be addressed by using a reference, either by measuring the sample and reference side-by-side in the instrument, or by measuring the sample and reference sequentially and then mathematically correcting the data afterward. Samples of liquid nanocrystal dispersions can be measured in glass, quartz, or plastic cuvettes, but due to the finite thickness of the cuvette walls, there are four interfaces where Fresnel reflections occur and two walls where absorption occurs. Using a cuvette of the same material, wall thickness, and path length as the reference will provide sufficiently accurate results.

[0046] For thin film nanocomposites, the coated substrate is measured either side-by-side or sequentially against a blank substrate made of the same material with the same thickness and surface smoothness to correct for absorption and reflection at the interface. The coating has a different refractive index than the substrate and air. Because the reflectance at the front surface of the film and substrate may differ slightly, the result is often a transmittance greater than 100% based on the algorithm used by the spectrophotometer. This effect can be corrected for, but the steps are tedious and the error is usually small. For convenience, the transmittance data presented in this disclosure is measured without correction.

[0047] Light that is not transmitted, scattered, or reflected is absorbed. Absorption can be calculated by subtracting the transmitted, scattered, and reflected light from the incident light.

[0048] The light transmittance at 450 nm of a formulation of the present disclosure without a curing agent 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%, when measured using a Perkin Elmer Lambda 850 spectrophotometer in a cuvette having a 1 cm path length.

[0049] The light transmittance at 400 nm of a formulation of the present disclosure without a curing agent 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%, when measured in a cuvette with a 1 cm path length using a PerkinElmer Lambda 850 spectrophotometer.

[0050] Formulations of the present disclosure have a viscosity of about 1 cP to about 12,000 cP. Formulations of the present disclosure have a viscosity of 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, about 500 cP, or about 1,000 cP when measured at 25°C using a Brookfield RVDV II+ cone and plate viscometer.

[0051] The refractive index is measured using a Metricon 2010 / M model Prism Coupler equipped with 448 nm and 635 nm laser beams. The estimated refractive index of the same material at a third wavelength can be calculated. The calculation of the refractive index at 550 nm is based on the Cauchy equation in binomial form.

number

[0052] Parameters A and B depend on the measured RI value at specific wavelengths, which were chosen to be 448 nm and 635 nm. By expressing parameters A and B in terms of RI(448 nm) and RI(635 nm), RI(550 nm) can be calculated using the following formula:

number

[0053] Formulation ingredients and properties The present disclosure provides solvent-free, low-viscosity, highly transparent, high-RI coatings comprising at least partially capped metal oxide nanocrystals dispersed in a monomer, oligomer, polymer, or mixture thereof. The formulations also include curing agents, adhesion promoters, wetting agents, leveling agents, dispersants, viscosity modifiers, organic dopants, and antioxidants. These formulations enable the creation of nanocomposites and thin coatings with high refractive index and optical transparency. These formulations are specifically designed for inkjet printing applications, and they desirably exhibit strong resistance to inkjet nozzle faceplate wetting and adequate wetting of the desired substrate. Liquids exhibit wetting properties with certain solid surfaces, forming a contact angle when the liquid reaches equilibrium. Low contact angles, typically less than 10°, indicate high wetting of the liquid with the surface. High wetting results in uniform coatings. Contact angles greater than 45° indicate partial or no wetting. In such cases, irregular surfaces and possible lens printing are likely the result, often indicating a high-surface-tension liquid on a low-surface-energy surface.

[0054] The resulting nanocomposite film desirably has a medium to high degree of cure, good adhesion to the intended substrate, and good film uniformity.

[0055] Although the formulations described herein focus on the application of UV radiation for curing, thermal curing is entirely possible with the use of an appropriate thermal initiator, such as 2,2-azobis(2-methylpropionitrile) (AIBN).

[0056] Combinations of multiple curing agents may be advantageous in certain circumstances as known to those skilled in the art.

[0057] The amount of curing agent in the formulations of the present disclosure is present in an amount of less than 0.5% by weight of the total monomers, oligomers, and / or polymers, or 0.5% to 1% by weight of the total monomers, oligomers, and / or polymers, or 1% to 2% by weight of the total monomers, oligomers, and / or polymers, or 2% to 3% by weight of the total monomers, oligomers, and / or polymers, or 3% to 4% by weight of the total monomers, oligomers, and / or polymers, or 4% to 5% by weight of the total monomers, oligomers, and / or polymers, or 5% to 6% by weight of the total monomers, oligomers, and / or polymers, or 6% to 7% by weight of the total monomers, oligomers, and / or polymers, or 7% to 8% by weight of the total monomers, oligomers, and / or polymers, or 8% to 15% by weight of the total monomers, oligomers, and / or polymers.

[0058] When present, the adhesion promoter is selected from organometallic compounds, such as organofunctional silanes, or from functionalized monomers and oligomers. Good film uniformity with some organic substrates.

[0059] The nanocrystals of the present disclosure include nanocrystals of metal oxides, such as titanium oxide, hafnium oxide, zinc oxide, tantalum oxide, niobium oxide, or a mixture of at least two of the foregoing oxides, which have a high bulk refractive index, typically greater than 2, as well as high transparency, due to their large band gap in the visible spectrum.

[0060] The capped nanocrystals of the present disclosure have an average size range of 3-40 nm, as measured by transmission electron microscopy (TEM), with a narrow size distribution.

[0061] For example, the capped nanocrystals of the present disclosure, when dispersed in a solvent such as PGMEA at a concentration of 5 wt % or less, can be measured by dynamic light scattering (Malvern Zetasizer Nano S). Zetasizer Nano S Dynamic Light Scatteri The nanocrystals are monodisperse, with an average size of less than 20 nm as measured using a DLS (Digital Light Spectroscopy) instrument. DLS measures particle size along with the solvent shell surrounding the nanocrystals. The capped nanocrystals of the present disclosure remain dispersible or agglomerate-free in the polymer or monomer matrix. Such physical properties of the materials of the present disclosure not only reduce light scattering but also improve processability.

[0062] The capped nanocrystals of the presented disclosure are prepared by the methods described in Provisional Patent Application No. 62 / 769,703 and Patent No. US8592511B2, the entire contents of which are incorporated herein by reference.

[0063] The nanocrystals of the present disclosure are at least partially capped with specific functional groups, also referred to as capping agents or capping groups. These specific functional groups are grafted onto the surface of the nanocrystals. The capping reaction is carried out in the presence of water. As used herein, a capped nanocrystal and an at least partially capped nanocrystal are functionally equivalent.

[0064] Capping agents for the capped nanocrystals in the formulations of the present disclosure include silanes, carboxylic acids, and / or alcohols. Examples of silanes of the present disclosure include, but are not limited to, methyltrimethoxysilane, n-propyltrimethoxysilane, n-propyltriethoxysilane, noctyltrimethoxysilane, 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, and glycidoxypropyltrimethoxysilane, vinyltrimethoxysilane, allyltrimethoxysilane, 1-hexenyltrimethoxysilane, 1-octenyltrimethoxysilane, or any combination thereof.

[0065] Examples of alcohols of the present disclosure include, but are not limited to, heptanol, hexanol, octanol, benzyl alcohol, phenol, ethanol, propanol, butanol, oleyl alcohol, dodecyl alcohol, octadecanol, triethylene glycol monomethyl ether, or any combination thereof.

[0066] Examples of carboxylic acids of the present disclosure include, but are not limited to, 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)ethyl succinate, or any combination thereof.

[0067] The monomers, oligomers, and / or polymers of the formulations of the present disclosure include acrylics, vinyls, or combinations thereof.

[0068] The acrylic monomers, oligomers, and / or polymers of the formulations of the present disclosure include 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, HDDMA), di(ethylene glycol) Di(meth)acrylate (DEGDA, DEGDMA), ethylene glycol diacrylate, glycerol 1,3-diglycerolate diacrylate, tri(propylene glycol) diacrylate, 1,6-hexanediol ethoxylate diacrylate, ethylene glycol phenyl ether (meth)acrylate (PEA, PEMA), 2-hydroxy-3-phenoxypropyl acrylate (HPPA), 2-hydroxy-3-phenoxypropyl methacrylate (HPPMA), 2-phenoxybenzyl acrylate Examples of suitable resins include acrylate (PBA), biphenyl methacrylate (BPMA), 2-phenylphenol methacrylate (PPMA), isobutyl acrylate (IBA), 2-phenylethyl acrylate (2-PEA), 2-(phenylthio)ethyl acrylate (PTEA), sulfur-containing commercially available resins and adhesives, such as #18109, #18165, and #6205 (NTT-AT); and Lumiplus LP-1100, LPB-1102, LPJ-1102, LPS-1130 (Mitsubishi Gas Chemical), or combinations thereof.

[0069] 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.

[0070] Formulations of the present disclosure include mercapto-functional monomers such as trimethylolpropane tri(3-mercaptopropionate) (TMPMP), pentaerythritol tetra(3-mercaptopropionate) (PETMP), ethylene glycol dimercaptopropionate, ethylene glycol dimercaptoacetate, thiodiethanethiol, bis(mercaptoethyl)ether, 2,2'-(ethylenedioxy)diethanethiol, and combinations thereof.

[0071] The formulations of the present disclosure include organic dopants to increase the refractive index of the film or coating, when present, including phenanthrene (PhA), 9-cyanophenanthrene, triphenylmethane, benzoquinoline, 9-vinylcarbazole, and combinations thereof.

[0072] The curing agent of the formulation of the present disclosure includes a photoinitiator. Any photoinitiator can be used as long as it can generate active species such as radicals using light (UV) energy, provided that it does not limit the optical and physical performance of the nanocomposite. Examples of photoinitiator curing agents include amines, such as Ebecryl® P115, or benzophenone and its derivatives, such as Ebecryl® P39 and Speedcure BEM (Lambson USA, Rutherford, Connecticut, USA), or organic phosphines, such as diphenyl(2,4,6-trimethylbenzoyl)-phosphine oxide (TPO), Irgacure® 819, or Irgacure® 184 (BASF USA, Florham Park, New Jersey, USA). The formulation includes a single photoinitiator or any combination thereof and a suitable silane adhesion promoter containing 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 monomeric and oligomeric adhesion promoters include, but are not limited to, CN820, CN146 (Sartomer Americas, Exton, PA, USA), SR9051, SR9053 (Sartomer Americas, Exton, PA, USA), and Ebecryl 171 (Allnex USA Inc., Wallingford, CT, USA).

[0073] 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 0.5-1% by weight of the monomer, oligomer, and / or polymer, or 1-5% by weight of the monomer, oligomer, and / or polymer, or 5-10% by weight of the monomer, oligomer, and / or polymer, or 10-15% by weight of the monomer, oligomer, and / or polymer, or 15-30% by weight of the monomer, oligomer, and / or polymer.

[0074] Surfactants that act as wetting agents, leveling agents, antifoaming agents, and dispersants are optionally present to reduce the surface tension of the formulation, thereby improving the flow characteristics of the formulation and producing a more uniform dried coating surface. The surfactants may be 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 Co., Ltd.), fluorosurfactants such as Novec 4430, Novec 4432, Novec 4434 (3M, St. Paul, MN, USA), and Capstone FS-3100 (Chemars, Wilmington, DE, USA). Leveling agents are optionally used. Examples of leveling agents include 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); polyether-modified, acrylic-functional siloxanes such as BYK-UV3530. Examples of dispersing agents include, without limitation, polyalkylene glycols and their esters, polyoxyalkylenes, polyhydric alcohol ester alkylene oxide adducts, alcohol alkylene oxide adducts, sulfonic acid esters, sulfonic acid salts, carboxylic acid esters, carboxylic acid salts, alkylamide alkylene oxide adducts, alkylamines, and the like, used alone or in a mixture of two or more.Commercially available examples of dispersants include, without limitation, Disper BYK-101, Disper BYK-130, Disper BYK-140, Disper BYK-160, Disper BYK-161, Disper BYK-162, Disper BYK-163, Disper BYK-164, Disper BYK-165, Disper BYK-166, Disper BYK-170, Disper BYK-171, Disper BYK-182, Disper BYK-2000, Disper BYK-2001 (BYK-Chemie Co., Ltd.), Solsperse 32000, Solsperse 36000, Solsperse 28000, Solsperse 20000, Solsperse 41000, and Solsperse 45000 (Lubrizol, Wickliffe, Ohio, USA).

[0075] The amount of surfactant in the formulations of the present disclosure, for purposes of improving wetting, is present in an amount of 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. The amount of surfactant in the formulations of the present disclosure, for purposes of aiding dispersion, varies depending on the material being dispersed. The amount of dispersing agent 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.

[0076] The antioxidant of the formulations of the present disclosure includes at least one primary antioxidant, which may be a sterically hindered phenol, such as Irganox 1010, Irganox 1076, Songnox® 1076, Songnox® 2450, or or phenol phosphites, such as Songnox® 1680, or phosphines, such as Irgaphos 168 (BASF USA, Florham Park, NJ, USA), or aromatic secondary amines or sterically hindered amines, such as SongLight® 6220 (Songwon Americas, Friendwood, TX, USA).

[0077] The formulations of the present disclosure include at least one secondary antioxidant. This 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).

[0078] The amount of antioxidant in the formulations 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.

[0079] The formulations of the present disclosure may further comprise a plasticizer, toughener, thickener, diluent, dispersant, or softener, or other functional additive.

[0080] The formulations of the present disclosure further include small concentrations of solvent (within the definitions of "solvent-free" and "solvent-free") to maintain a lower viscosity. The choice of solvent is entirely dependent on the type of capped nanocrystal and the selected monomers, oligomers, and polymers of the formulation. Examples of common solvents ranging from low to high boiling points include alcohols, glycols, methyl acetates, ethyl acetates, 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, ethoxyethyl acetate, butoxyethyl acetate, 2-(isopentyloxy)ethanol, 2-(hexyloxy)ethanol, diethylene glycol, diethylene glycol monomethyl ether, diethylene glycol, diethylene glycol monoethyl ether, triethylene glycol, triethylene glycol monomethyl ether, dipropylene glycol, dipropylene glycol monomethyl ether, dipropylene glycol monoethyl ether, ethyl acetate, THF, acetone, and any combination thereof.

[0081] The formulations of the present disclosure exhibit tunable viscosity and / or viscosity controlled by one or more components of the formulation. Parameters that 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, as well as the presence and concentration of solvents, the presence and concentration of thickeners (i.e., viscosity-modifying components), particle size of components present in the formulation, temperature, and combinations thereof.

[0082] The formulations of the present disclosure are stable for longer than 1 week, or longer than 2 weeks, or longer than 3 weeks, or longer than 6 weeks, or longer than 8 weeks, or longer than 3 months, or longer than 6 months, or longer than 12 months, or longer than 36 months, without significant increase in viscosity. Also, it is desirable that there is no visible precipitation of the capped nanocrystals, and the change in formulation viscosity is less than 10%. or less than 20%, or less than 30%, or less than 40%, or less than 50%, or less than 100%. Further, the change in light transmittance of the formulation at 450 nm is desirably less than a 10% decrease in transmittance, 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.

[0083] For inkjet printing purposes, jetting of the formulations of the present disclosure 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, and the formulations do not dry out or harden, which can lead to clogging of the nozzles of the print head. Solvent-free or solvent-free formulation manufacturing methods

[0084] In some embodiments, the present disclosure provides a method for producing a solvent-free nanocomposite formulation comprising: direct dispersion (dispersing nanocrystals directly in a medium), separating the capped nanocrystals from the solvent and drying under vacuum until the solvent content is less than 5% to form dry nanocrystals; and mixing the dry nanocrystals of at least partially capped metal oxide nanocrystals with at least one monomer, oligomer, polymer, or mixture thereof by immersion, stirring, high-speed mixing, microfluidizing, or other mixing methods. In further embodiments, the method further comprises filtering the mixture to remove aggregates or other contaminants.

[0085] In some embodiments, the present disclosure provides a method for producing a solvent-free formulation, comprising: mixing a dry powder of at least partially capped metal oxide nanocrystals in at least one solvent by immersion, stirring, high-speed mixing, microfluidizing, or other mixing methods to provide a nanocrystal solvent dispersion; mixing the dispersion with at least one monomer, oligomer, polymer, or mixture or monomer, oligomer, and / or polymer to provide a solvent-containing formulation; and removing the solvent by evaporation or other solvent removal methods, such as rotovap. In further embodiments, the method further comprises filtering the solvent-containing or solvent-free formulation to remove aggregates or other contaminants. In some embodiments, the solvent used according to the method comprises ethyl acetate, methyl ethyl ketone, or other low-boiling point solvent. Nanocomposite Properties

[0086] Nanocomposites, including films, coatings, layers, and lenses, on a substrate or freestanding. The present disclosure provides nanocomposites comprising an organic polymerizable matrix, a curing agent, and a mixture of capped nanocrystals, wherein the capped nanocrystals are present in the nanocomposite in an amount of 20-80% by weight of the nanocomposite. Further refined loadings for inkjet printable formulations are 30-70% by weight, and are highly dependent on the selection of monomers, oligomers, polymers, and solvents, if present.

[0087] The nanocomposites of the present disclosure comprise nanocrystals of a metal oxide, such as titanium oxide, hafnium oxide, zinc oxide, tantalum oxide, niobium oxide, or a mixture of at least two of the foregoing oxides.

[0088] Capping agents for the capped nanocrystals in the nanocomposites of the present disclosure include silanes, carboxylic acids, and / or alcohols. Examples of silanes of the present disclosure include methyltrimethoxysilane, n-propyltrimethoxysilane, n-propyltriethoxysilane, noctyltrimethoxysilane, n-octyltriethoxysilane, phenyltrimethoxysilane, dodecyltrimethoxysilane, m,p-ethylphenethyltrimethoxysilane, 2-[methoxy(polyethyleneoxy)propyl]trimethoxysilane, methoxy Examples of the silane include, but are not limited to, (triethyleneoxy)propyltrimethoxysilane, 3-aminopropyltrimethoxysilane, 3-mercaptopropyltrimethoxysilane, 3-(methacryloyloxy)propyltrimethoxysilane, 3-(acryloyloxy)propyltrimethoxysilane, 3-isocyanatopropyltriethoxysilane, 3-isocyanatopropyltrimethoxysilane, and glycidoxypropyltrimethoxysilane, vinyltrimethoxysilane, allyltrimethoxysilane, 1-hexenyltrimethoxysilane, 1-octenyltrimethoxysilane, or any combination thereof.

[0089] Examples of alcohols of the present disclosure include, but are not limited to, heptanol, hexanol, octanol, benzyl alcohol, phenol, ethanol, propanol, butanol, oleyl alcohol, dodecyl alcohol, octadecanol, triethylene glycol monomethyl ether, or any combination thereof.

[0090] Examples of carboxylic acids of the present disclosure include, but are not limited to, 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)ethyl succinate, or any combination thereof.

[0091] The inorganic solids content of the nanocomposite coatings or films of the present disclosure is analyzed using a TA Instruments Q500 Thermogravimetric Analyzer (TGA), the procedure being the same as previously described.

[0092] The inorganic solids content of the nanocomposite coatings of the present disclosure is in the range of 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.

[0093] The monomer units of the polymer matrix of the nanocomposite coatings or films of the present disclosure include acrylics, benzyl methacrylate (BMA), benzyl acrylate (BA), trimethylolpropane triacrylate (TMPTA), trimethylolpropane trimethacrylate (TMPTMA), trimethylolpropane ethoxylate triacrylate (EOTMPTA), trimethylolpropane ethoxylate trimethacrylate (EOTMPTMA), 1,6-hexanediol diacrylate (HDDA), 1,6-hexanediol dimethacrylate (HDDMA), di(ethylene glycol) diacrylate (DEGDA), di(ethylene glycol) dimethacrylate (DEGDMA), ethylene glycol The acrylic acid esters may include glycerol diacrylate, glycerol 1,3-diglycerate diacrylate, tri(propylene glycol) diacrylate, 1,6-hexanediol ethoxylate diacrylate, 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), or any combination thereof.

[0094] The nanocomposites of the present disclosure have a refractive index at 550 nm of 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 1.76-1.78, or 1.78-1.80, or 1.80-1.82, or 1.82-1.84, or 1.84-1.86, or 1.86-1.88, or 1.88-1.90, or 1.90-1.92, or 1.92-1.94.

[0095] The nanocomposites of the present disclosure further exhibit a pencil hardness of 2H or greater, 3H or greater, or 4H or greater, or 5H or greater, or 6H or greater, when tested according to the method of ASTM D3363.

[0096] The nanocomposites of the present disclosure have high visible light (400-800 nm) transmittance of 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%, 60%-55%, 55%-50%, 50%-45%, 45%-40%, 40%-35%, 35%-30%, 30%-25%, 25%-20%, 20%-15%, or 15%-10% for films less than 20 microns thick. The transmittance of films according to the present disclosure includes normal transmittance measured using a PerkinElmer UV-Vis Lambda 850 spectrophotometer, where the nanocomposite is coated onto 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.

[0097] The nanocomposites of the present disclosure further exhibit thermal stability at temperatures of 120° C. or greater, or 175° C. or greater, or 200° C. or greater, or 250° C. or greater, or 260° C. or greater, or 300° C. or greater. Thermal stability is measured by storing the nanocomposite in air, nitrogen, or under vacuum at the specified temperature for 5 minutes or greater, or 10 minutes or greater, or 30 minutes or greater, or 60 minutes or greater, or 120 minutes or greater without visible discoloration, cracking, or delamination, and without less than 10% loss in transmittance at 400 nm, or less than 20% loss in transmittance, or less than 30% loss in transmittance, or less than 40% loss in transmittance, or less than 50% loss in transmittance. Method for producing the nanocomposite of the present invention

[0098] The present disclosure provides methods for making nanocomposites using the formulations of the present disclosure. Nanocomposite films comprising the cured or partially cured formulations of the present disclosure are described herein. The nanocomposites are cured or partially cured by UV or thermal curing techniques known to those skilled in the art.

[0099] The present disclosure provides nanocomposite films as described herein, wherein the films are produced by depositing the formulation onto a surface by spin coating, slot die coating, screen printing, inkjet printing, nanoimprinting, photopatterning, 3D printing, dip coating, draw bar coating, roll-to-roll printing, spray coating, dispensing, volume casting, screen printing, and any combination thereof. Device

[0100] The present disclosure provides devices including active components, the active components including or containing the nanocomposites of the present disclosure. Smart windows, sensors, CMOS sensors, LEDs, mini LEDs, micro LEDs, organic LEDs (OLEDs), quantum LEDs (QLEDs), touch screens, displays, flexible electronics, printed electronics devices including sensors, self-cleaning surfaces, augmented reality (AR), mixed reality (MR), and virtual reality (VR), waveguides, light extraction, and 3D sensors. [Example]

[0101] Example 1 The capped ZrO2 nanocrystals described above in the embodiments were dispersed in a desired monomer, such as BA or PEA, via direct dispersion (see paragraph 1 for solvent-free or solvent-free formulation manufacturing methods), and diluted with a crosslinker, such as TMPTA, HDDA, and TMPMP, to achieve the desired zirconia loading in the formulation ranging from 35% to 70% by weight, BA weight percent ranging from 4 to 20% by weight, PEA weight percent ranging from 20 to 40% by weight, TMPTA weight percent ranging from 2 to 5% by weight, TMPMP weight percent ranging from 3 to 5% by weight, HDDA weight percent ranging from 1 to 3% by weight, and BYK378 weight percent ranging from 0.5 to 1.0% by weight in the formulation. Representative formulations of Example 1 are designated Formulations A1 to A10 according to Table 1 below. [Table 2]

[0102] Example 1A Formulation A10, which contained 35 wt% capped ZrO2 nanocrystals in a blend of acrylates consisting of 27.6 wt% BA, 27.6 wt% PEA, 4.9 wt% TMPTA, and 4.9 wt% TMPMP, and exhibited a viscosity of 11.5 cP, was added with a photoinitiator (Irgacure® 819 photoinitiator) in an amount of 4 wt% relative to the monomer content. Formulation A10 with the photoinitiator added was deposited as a film having a thickness of 10 microns on a glass substrate. The film was cured under 1 J / cm2 of 385 nm UV light, resulting in a cured film with a refractive index of 1.58 at 550 nm.

[0103] Example 2 The ZrO2 capped nanocrystals used in Example 1 were dispersed in benzyl acrylate (BA) monomer in the same manner as previously described to achieve nanocrystal loadings of several weight percent (NC wt%) and form nanocomposites. A siloxane surfactant (BYK 378, available from BYK Chemie GmbH) was added in an amount of 1.0 wt% to achieve nanocrystal loadings of several weight percent (NC wt%). For all formulations, the weight percentage of capped nanocrystals ranged from 35 to 70 wt%, the weight percentage of BA ranged from 35 to 70 wt%, and the weight percentage of BYK 378 ranged from 0.5 to 1.0 wt%.

[0104] Nanocomposites B1 and B2 contain 50 wt% (23.3 vol%) nanocrystals in BA, without and with 1 wt% BYK 378 surfactant, respectively. Figure 1 shows the viscosity behavior of uncured formulation B1 at 25°C versus weight percent of zirconia nanoparticles. Nanocomposite B1 at 50 wt% nanocrystals has a nanocomposite formulation viscosity of 10 cP. Figure 2 shows the relationship of cured B1 film RI at 550 nm (calculated from measurements made at 448 nm and 635 nm) versus volume percent of zirconia nanoparticles for the formulations illustrated in this example. Nanocomposite B1 at 50 wt% nanocrystals has a nanocomposite film RI at 550 nm of 1.624. Viscosity versus temperature behavior is an important relationship for certain inkjet printheads. Figure 3 displays the viscosity-temperature relationship for the uncured formulations of nanocomposites B1 and B2, along with two other nanocomposites described in Example 3 for comparison. The viscosity of nanocomposites B1 and B2 decreases from approximately 9.1-9.8 cP at 25°C to 5.0-5.2 cP at 50°C.

[0105] Example 3 The ZrO2 capped nanocrystals used in Example 1 were dispersed in a desired monomer blend, e.g., BA, NVP, and PBA, along with a surfactant, e.g., BYK378, to achieve the desired zirconia loading in the formulation, ranging from 30 to 70 wt%. The preferred capped nanocrystal weight percentages for the total formulation range from 35 to 60 wt%, the weight percentage of BA from 15 to 30 wt%, the weight percentage of NVP from 5 to 20 wt%, the weight percentage of PBA from 5 to 20 wt%, and the weight percentage of BYK378 from 0.5 to 1.0 wt%. The combination of PBA and BYK378 results in little to no nozzle plate wetting in certain inkjet printheads, such as the Dimatrix DMC and KM1024i HE series. Figure 4 shows three photographs illustrating nozzle plate wetting ranging from severe (top), moderate (middle), to none (bottom).

[0106] Example 3A Specific examples are formulations with 40 wt% capped nanocrystals in a blend of acrylates consisting of 30.0 wt% BA, 30.0 wt% PBA, and BYK 378 (Nanocomposite C1 - no BYK 378; Nanocomposite C2 - 1.0 wt% BYK 378). At 378 (for all formulations), nanocomposite C2 has a viscosity of 14.2 cP and a surface tension of 22.0 dyne / cm at 25°C. Irgacure 819 photoinitiator was added to the C2 formulation at 4 wt% (relative to monomer content) and deposited as a film. 10-micron films of each formulation were coated on glass substrates and cured under 1 J / cm2 of 385 nm UV light to have a refractive index of 1.64 at 550 nm. The resulting films are nanocomposites C1 and C2. The viscosity versus temperature relationship for the nanocomposite C1 and C2 formulations is shown in Figure 3. The viscosity of nanocomposites B1 and B2 decreases from approximately 12.5-14 cP at 25°C to 6.1-7.02 cP at 50°C.

[0107] Example 3B Another example is a formulation with 45 wt% capped nanocrystals in a blend of acrylates consisting of 27.5 wt% BA, 16.5 wt% NVP, 11.0 wt% PBA, and BYK 378 (Nanocomposite D1 - no BYK 378; Nanocomposite D2 - 1.0 wt% BYK 378 for the total formulation, Nanocomposite D2 , has a viscosity of 10.1 cP at 25°C and a surface tension of 22.0 dynes / cm.

[0108] TGA scans were used to characterize the percent solids in the formulation and are described on page 11. Another characterization tool, UV-Vis spectroscopy, was used to determine the optical density of the uncured formulation and is described on page 12. Figures 5 and 6 show the TGA scan and optical density vs. wavelength curve graph, respectively, of Nanocomposite D2. The TGA scan indicates a residual amount after heating to 700°C of 38.46%. The optical density (OD) values ​​at 350 nm and 450 nm are approximately 1.20 and 0.15, respectively.

[0109] Irgacure 819 photoinitiator was added to nanocomposite D2 at 4 wt% (with respect to monomer content) and deposited as a film. A 10 micron film applied to a glass substrate was cured under 385 nm UV at 1 J / cm2 and had a refractive index of 1.64 at 550 nm.

[0110] Another example is a formulation containing 50 wt% capped nanocrystals in a blend of acrylates consisting of 25.0 wt% BA, 15.0 wt% NVP, 10.0 wt% PBA, and 1.0 wt% BYK 378. Adding 1.0 wt% BYK 378 to this mixture formed nanocomposite D3, which had a viscosity of 14.2 cP at 25°C and a surface tension of 22.0 dyne / cm. Irgacure 819 photoinitiator was added to the formulation at 4 wt% (relative to the monomer content) and deposited as a film. The film was cured under 1 J / cm2 of 385 nm UV light and had a refractive index of 1.651 at 550 nm.

[0111] Typical optical properties of cured nanocomposite films are transmittance and refractive index across wavelengths in the visible range (400 to 700 nm). Figures 7 and 8 show the refractive index vs. wavelength and %T vs. wavelength curves for a 10 μm thick nanocomposite D3 film, which has a film RI of 1.651 and a transmittance at 550 nm of 96.5%. Table 3 provides the composition, formulation viscosity, nanocomposite film RI, and nozzle wetting behavior of various formulations containing nanocomposites D2 and D3. [Table 3]

[0112] Example 4 The ZrO2-capped nanocrystals used in Example 1 were dispersed in the desired monomer blend, e.g., BA, NVP, PBA, and BPMA, along with a surfactant, e.g., BYK 378, in the same manner as described above to achieve the desired zirconia loading in the formulation, ranging from 30 to 70 wt%. The preferred capped nanocrystal weight percentages are in the range of 35 to 60 wt%, BA weight percentages in the range of 15 to 30 wt%, NVP weight percentages in the range of 5 to 20 wt%, PBA weight percentages in the range of 5 to 20 wt%, BPMA weight percentages in the range of 10 to 30 wt%, and BYK 378 weight percentages in the range of 0.5 to 1.0 wt%. Table 3 includes the compositions, viscosities, cured film RI, and nozzle plate wetting observations for nanocomposites E1 to E6 of this example.

[0113] Example 4A A specific example is Nanocomposite E6, a formulation with 40 wt% capped nanocrystals in a blend of acrylates consisting of 18.0 wt% BA, 12.0 wt% NVP, 18.0 wt% PBA, 12.0 wt% BPMA, and 1.0 wt% BYK 378, which has a viscosity of 17.6 cP at 25°C and a surface tension of 22.0 dynes / cm.

[0114] Irgacure 819 photoinitiator was added to the formulation at 4 wt% (relative to the monomer content) and it was deposited onto a glass substrate as a 10 micron film, which was cured under 1 J / cm2 of 385 nm UV light and had a refractive index of 1.643 at 550 nm.

[0115] Example 5 The capped ZrO2 nanocrystals used in Example 1 were dispersed in the desired monomer blend, e.g., BA, NVP, PBA, and BPMA, along with a surfactant, e.g., BYK 378, in the same manner as previously described to achieve the desired zirconia loading in the formulation, and a solvent, e.g., PGMEA, was added to reduce viscosity. The preferred minor amount of PGMEA added is 1-10 wt% of the total formulation to provide the solvent-free and solvent-less formulations according to the present invention.

[0116] Example 5A Two specific examples are nanocomposite F1, with 80 wt% capped nanocrystals in 20 wt% PEA, with an initial viscosity of 5,755 cP at 25° C., and nanocomposite F2, with 75 wt% capped nanocrystals in 25 wt% BA, with an initial viscosity of 140.6 cP at 25° C. Figure 9 shows that as PGMEA is added to nanocomposites F1 and F2 for the entire formulation, the viscosity decreases to approximately 100 cP and 30 cP at 10% dilution, respectively.

[0117] Example 6 The capped ZrO nanocrystals used in Example 1 were dispersed in the desired monomer blend, e.g., BA, NVP, PBA, and BPMA, along with a surfactant, e.g., BYK 378, in the same manner as described above to achieve the desired zirconia loading in the formulation, and an organic dopant, e.g., phenanthrene (PhA), was added. The preferred capped nanocrystal weight percentage, based on the monomer content, is in the range of 35-60 wt%, the weight percentage of BA is in the range of 15-30 wt%, the weight percentage of NVP is in the range of 5-20 wt%, the weight percentage of PBA is in the range of 5-15 wt%, the weight percentage of BPMA is in the range of 10-30 wt%, the weight percentage of PhA is in the range of 10-20 wt%, and the weight percentage of BYK 378 is in the range of 0.5-1.0 wt% of the total formulation. Table 4 shows the composition, formulation viscosity, and nanocomposite film RI for various materials with and without the addition of PhA. Table 4 shows examples of nanocomposites D3, D4, D5, G1, and G2.

[0118] Example 6A A specific example, Nanocomposite G1, is a formulation with 50 wt% capped nanocrystals in a blend of acrylates consisting of 20.3 wt% BA, 12.2 wt% NVP, 8.2 wt% PBA, and 9.3 wt% PhA, and has a viscosity of 18.1 cP at 25°C.

[0119] Irgacure 819 photoinitiator was added to the formulation at 4 wt% (relative to the monomer content) and deposited as a 10 micron film on a glass substrate. The film was cured under 1 J / cm2 of 385 nm UV light and had a refractive index of 1.668 at 550 nm.

[0120] Another example, Nanocomposite G2, is a formulation with 59.7 wt% capped nanocrystals in a blend of acrylates consisting of 16.6 wt% BA, 10.0 wt% NVP, 7.0 wt% PBA, and 6.6 wt% PhA, and has a viscosity of 42.2 cP at 25°C.

[0121] Irgacure 819 photoinitiator was added to the formulation at 4 wt% (with respect to the monomer content) and deposited as a film, which was cured under 1 J / cm2 of 385 nm UV light and had a refractive index of 1.683 at 550 nm. [Table 4]

[0122] Example 7 The capped ZrO nanocrystals used in Example 1 were dispersed in the desired monomer blends, such as BA, NVP, PBA, STY, and / or 4-methylstyrene (4MS), divinylbenzene (DVB), and 4-vinylanisole (4VA), in the same manner as described above, and an organic dopant, such as 9-vinylcarbazole (NVCb), was added to form nanocomposites H1-H5. Surfactants, such as BYK 333, and dispersants, such as FLOWLEN G-700, were optionally added to improve inkjet performance. The preferred capped nanocrystal weight percentage is in the range of 35-60 wt%, the weight percentage of BA is in the range of 15-30 wt%, the weight percentage of NVP is in the range of 5-20 wt%, the weight percentage of PBA is in the range of 5-15 wt%, the weight percentage of STY is in the range of 10-20 wt%, the weight percentage of DVB is in the range of 10-20 wt%, the weight percentage of 2-PEA is in the range of 2-30 wt%, the weight percentage of NVCb with respect to monomer content is in the range of 5-35 wt%, the weight percentage of BYK333 is in the range of 0.01-1.0 wt%, and the weight percentage of FLOWLen G-700 dispersant is in the range of 0.01-1.0 wt%. Table 5 shows the composition, formulation viscosity, and nanocomposite RI of various materials with and without the addition of STY, 4MS, DVB, 4VA, 2-PEA, and NVCb. [Table 5]

[0123] Example 7A A specific example, Nanocomposite H1, is a formulation with 47.5 wt% capped nanocrystals in a blend of acrylates and vinyl monomers consisting of 13.0 wt% BA, 7.9 wt% NVP, 5.2 wt% PBA, 4.8 wt% STY, and 16.0 wt% NVCb, and has a viscosity of 21.3 cP at 25°C.

[0124] Irgacure 819 photoinitiator was added to the formulation at 4 wt% (relative to the monomer content) and it was deposited onto a glass substrate as a 10 micron film, which was cured under 1 J / cm2 of 385 nm UV light and had a refractive index of 1.690 at 550 nm.

[0125] Another specific example, Nanocomposite H2, is a formulation with 47.5 wt% capped nanocrystals in a blend of acrylate and vinyl monomers consisting of 13.0 wt% BA, 7.9 wt% NVP, 5.2 wt% PBA, 4.8 wt% 4MS, and 16.0 wt% NVCb, and has a viscosity of 18.2 cP at 25°C.

[0126] Irgacure 819 photoinitiator was added to the formulation at 4 wt% (relative to the monomer content) and deposited as a 10 micron film on a glass substrate. The film was cured under 1 J / cm2 of 385 nm UV light and had a refractive index of 1.692 at 550 nm.

[0127] The third example, Nanocomposite H4, is a formulation with 47.5 wt% capped nanocrystals in a blend of acrylates and vinyl monomers consisting of 13.0 wt% BA, 7.9 wt% NVP, 5.2 wt% PBA, 2.4 wt% STY, 2.4% DVB, and 16.0 wt% NVCb, and has a viscosity of 20.3 cP at 25°C.

[0128] Irgacure 819 photoinitiator was added to the formulation at 4 wt% (relative to the monomer content) and it was deposited onto a glass substrate as a 10 micron film, which was cured under 1 J / cm2 of 385 nm UV light and had a refractive index of 1.699 at 550 nm.

[0129] Example 8 Capped TiO nanocrystals having an average particle size of about 10 nm as measured by DLS intensity as described above in the embodiments were dispersed in the desired monomer, e.g., BA or PBA, via direct dispersion to achieve the desired zirconia loading in the formulation ranging from 35 wt% to 70 wt%, and the weight percentage of BA or PBA ranging from 30 to 65 wt%.

[0130] A specific example includes approximately 10 nm capped TiO2 nanocrystals dispersed in a desired monomer blend, such as BA and PBA, in the same manner as previously described. Table 6 shows the composition, viscosity, formulation RI value at 589 nm, cured film RI value at 550 nm, film thickness, and %T at 400 nm and 700 nm for nanocomposites I1-I8.

[0131] Figure 10 shows the relationship between nanocomposite formulation viscosity at 25 °C for different weight percent loadings of approximately 10 nm TiO particles in BA and PBA monomers. For inkjet printable formulations, the preferred capped nanocrystal weight percent is in the range of 40-60 wt%, and the BA weight percent is in the range of 40-60 wt%, resulting in viscosities approaching 8-30 cP. For higher viscosity applications (30-1,000 cP), such as slot-die coating and nanoimprinting, even higher TiO loadings are required. , between 40 and 80 wt%, and the weight percentage of PBA ranges from 30 to 60 wt%. Figure 11 shows that when approximately 10 nm of TiO2 is dispersed in BA and PBA monomers, the RI at 589 nm of the uncured nanocomposite formulation varies between 1.59 and 1.69. The RI values ​​of the cured nanocomposite films at 550 nm are shown in Figure 12, and the values ​​range from 1.65 to 1.75. [Table 6]

[0132] Example 9 Capped TiO nanocrystals with an average particle size of about 30 nm (core size about 12-18 nm) as measured by DLS intensity as described above in the embodiments were dispersed in the desired monomer, e.g., BA or PBA, via direct dispersion to achieve the desired zirconia loading in the formulation ranging from 35 wt% to 70 wt%, and the weight percentage of BA or PBA ranging from 30-65 wt%.

[0133] A specific example includes approximately 30 nm capped TiO2 nanocrystals dispersed in a desired monomer blend, such as BA and PBA, in the same manner as previously described. Table 7 shows the composition, viscosity, formulation RI value at 589 nm, cured film RI value at 550 nm, film thickness, and %T at 400 nm and 700 nm for nanocomposites J1-J7.

[0134] Figure 10 also shows the relationship between nanocomposite formulation viscosity at 25 °C for different weight percent loadings of approximately 30 nm TiO particles in BA and PBA monomers. For inkjet-printable formulations, the preferred capped nanocrystal weight percent is in the range of 40-65 wt%, with the BA weight percent in the range of 35-60 wt%, resulting in viscosities approaching 8-30 cP. For higher viscosity applications (30-2000 cP), such as slot-die coating and nanoimprinting, even higher TiO loadings are appropriate, between 40-80 wt%, with the PBA weight percent in the range of 30-60 wt%. Figure 11 also shows that the RI at 589 nm of the uncured nanocomposite formulations varies between 1.61 and 1.69 when approximately 30 nm TiO particles are dispersed in BA and PBA monomers. The RI values ​​of the cured nanocomposite films at 550 nm are shown in Figure 12 and range from 1.67 to 1.80. [Table 7]

[0135] Example 10 The capped TiO nanocrystals described above in the embodiments were dispersed in the desired monomers, such as BA, NVP, and PBA, via direct dispersion to yield a 45 wt% loading of approximately 30 nm TiO in a formulation of 27.5 wt% BA, 16.5 wt% NVP, and 11 wt% PBA, providing an exemplary inkjet-printable TiO ink. The 17.4 cP ink was printable using a Dimatrix inkjet printer at 30°C and 18 V, with no significant wetting of the nozzle plate observed. Figure 15 shows that the %T of an inkjet-printed 12-micron film was greater than 90% at wavelengths greater than 400 nm. The film RI at 550 nm for this film was measured to be 1.683.

[0136] Example 11 Capped nanocrystals containing both ZrO2 and TiO2, both with particle sizes of approximately 10 nm, were dispersed together in different ratios in the desired monomers in the same manner as previously described. Table 8 shows the composition, viscosity, and film RI (550 nm) data for nanocomposites K1 through K6, including results obtained from a 50 wt% loading of mixed ZrO2 and TiO2 nanocomposite. The ZrO2-only film (nanocomposite B1 described in Example 2) has the lowest RI and viscosity, 1.639 and 9.6 cP, respectively. Nanocomposite K3 (similar to nanocomposite I2 described in Example 8) represents a comparative TiO2-only film, with film RI and viscosity of 1.695 and 18.7 cP, respectively. Further examples of mixed ZrO2 / TiO2 nanocomposites are shown to have film RI values ​​greater than 1.70 with selected monomers and specific ratios, while maintaining viscosities below 30 cP. [Table 8]

[0137] Example 12 Both ZrO2 and TiO2 capped nanocrystals were separately dispersed in the desired sulfur-containing resin sold by NTT-AT in the same manner as previously described in PGMEA. The TiO2 in nanocomposites L4 through L6 has a particle size of approximately 30 nm. Table 9 shows the composition and film RI (550 nm) data for nanocomposites L1 through L6 and compares the results obtained with ZrO2 and TiO2 nanocrystals. Nanocomposites L4 through L6 have significantly higher film RI values, greater than 1.82. [Table 9]

[0138] Example 13 Both ZrO2 and TiO2 capped nanocrystals were separately dispersed in the desired sulfur-containing Lumiplus® resin sold by Mitsubishi Gas Chemical in the same manner as previously described with PGMEA. The TiO2 in nanocomposites L4 to L6 has particle sizes around 10 nm. Table 10 shows the composition and film RI (550 nm) data for nanocomposites M1 to M10 and compares the results obtained with ZrO2 and TiO2. Nanocomposites M7 and M8 particularly highlight examples with film RI values ​​greater than 1.90. [Table 10]

[0139] The "Summary" section and the "Abstract" may describe one or more, but not all, exemplary embodiments of the invention contemplated by the inventors, and are therefore not intended to limit the scope of the invention and the appended claims in any way.

[0140] The present invention has been described above with reference to functional components that illustrate the implementation of specified functions and relationships thereof. The boundaries of these functional components have been arbitrarily defined herein for convenience of description. Alternate boundaries may be defined so long as the specified functions and relationships thereof are appropriately performed.

[0141] For aspects of the invention described as genus, all individual species are individually considered separate aspects of the invention. When an aspect of the invention is described as "comprising" a feature, it is contemplated that the embodiment also "consisting of" or "consisting essentially of" that feature.

[0142] As used herein, the term "about" modifying a quantity related to the present invention refers to variations in the numerical amount that may occur, for example, through normal testing and handling, through unintentional errors in such testing and handling, through differences in the manufacture, source, or purity of the components employed in the present invention; and the like. As used herein, "about" of a particular value also includes that particular value, for example, about 10% includes 10%. Whether modified by the term "about," the claims include equivalents of the stated quantity. In one embodiment, the term "about" means within 20% of the reported numerical value.

[0143] Wherever possible, terms appearing in the singular herein include the plural of that term and / or vice versa, unless the context clearly dictates otherwise.

[0144] Wherever embodiments are described herein using the phrase "comprising," it is understood that otherwise similar embodiments described with the terms "consisting of" and / or "consisting essentially of" are also provided. However, when used as transitional phrases in the claims, each should be interpreted separately in its appropriate legal and factual context (e.g., "comprising"). "Comprising" is considered a more open-ended phrase, while "consisting of" is more exclusive, and "consisting essentially of" achieves a middle ground.

[0145] The term "and / or" as used herein in phrases 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 embodiments: 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.

[0146] The foregoing description of specific embodiments will fully clarify the general nature of the present invention, so that by applying knowledge within the skill of those skilled in the art, others may readily modify and / or adapt such specific embodiments for various uses 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 is to be understood that the terms and phrases used herein are for the purpose of description and not of limitation, and are to be interpreted as by one of ordinary skill in the art in light of the teaching and guidance.

[0147] The breadth and scope of the present invention should not be limited by any of the above-described exemplary embodiments.

[0148] All of the various aspects, embodiments, and options described herein can be combined in any and all variations.

[0149] The contents of each of the following applications are incorporated herein by reference in their entirety: 1) U.S. Provisional Application No. 62 / 769,703, filed November 20, 2018; 2) U.S. Provisional Application No. 62 / 892,625, filed August 28, 2019; and 3) International Application No. PCT / US2019 / 062439, entitled "SYNTHESIS, CAPPING, AND DISPERSION OF TiO2 NANOCRYSTALS," filed November 20, 2019, which claims priority to U.S. Provisional Application Nos. 62 / 769,703 and 62 / 892,625.

[0150] In some embodiments, the present disclosure may exclude any of the embodiments described in U.S. Provisional Application No. 62 / 892,630, filed August 28, 2019.

[0151] All publications, patents, and patent applications mentioned in this specification are incorporated herein by reference as if each individual publication, patent, or patent application was specifically and individually indicated to be incorporated by reference. In the event that any meaning or definition of a term in this document 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. A formulation comprising at least partially capped metal oxide nanocrystals and a matrix comprising at least one monomer, oligomer, or polymer, e.g., the at least partially capped metal oxide nanocrystals are dispersed in the matrix, and the metal oxide is zirconium oxide, titanium oxide, hafnium oxide, zinc oxide, tantalum oxide, niobium oxide, or a mixture of at least two of the foregoing oxides, the formulation comprising less than 5 wt. % solvent.

2. Hardeners, surfactants, wetting agents, antioxidants, adhesion promoters, leveling agents, dispersants, plasticizers, tougheners, thickeners, diluents, dispersing agents 10. The formulation of claim 1, optionally further comprising one or more agents independently selected from: softening agents, organic dopants, and other functional additives.

3. 10. The formulation of claim 1, wherein the matrix comprises one or more agents independently selected from acrylate and / or methacrylate monomers, a reactive diluent, a curing agent, and, optionally, at least one surfactant or at least one wetting agent.

4. A formulation according to any one of claims 1 to 3, wherein the at least partially capped nanocrystals have an average particle size in the range of 1 to 40 nm, preferably less than 30 nm, as measured by DLS or TEM.

5. The nanocrystals may be selected from the group consisting of methyltrimethoxysilane, n-propyltrimethoxysilane, n-propyltriethoxysilane, n-octyltrimethoxysilane, n-octyltriethoxysilane, phenyltrimethoxysilane, dodecyltrimethoxysilane, m,p-ethylphenyltrimethoxysilane, 2-[methoxy(polyethyleneoxy)propyl]trimethoxysilane, methoxy(triethyleneoxy)propyltrimethoxysilane, 3-aminopropyltrimethoxysilane, 3-mercaptopropyltrimethoxysilane, 3-(methacryloyloxy)propyltrimethoxysilane, 3-(acryloyloxy)propyltrimethoxysilane, 3-isocyanatopropyltriethoxysilane, 3-isocyanatopropyltrimethoxysilane, and glycidoxypropyltrimethoxysilane, vinyltrimethoxysilane, methyltrimethoxysilane, n-propyltriethoxysilane, n-octyltriethoxysilane, phenyltrimethoxysilane, dodecyltrimethoxysilane, m,p-ethylphenyltrimethoxysilane, 2-[methoxy(polyethyleneoxy)propyl]trimethoxysilane, methoxy(triethyleneoxy)propyltrimethoxysilane, 3-aminopropyltrimethoxysilane, 3-mercaptopropyltrimethoxysilane, 3-(methacryloyloxy)propyltrimethoxysilane, 3-(acryloyloxy)propyltrimethoxysilane, 3-isocyanatopropyltriethoxysilane, 3-isocyanatopropyltrimethoxysilane, and glycidoxypropyltrimethoxysilane.

5. The formulation of any one of claims 1 to 4, at least partially capped with at least one capping agent selected from the group consisting of silane, allyltrimethoxysilane, 1-hexenyltrimethoxysilane, 1-octenyltrimethoxysilane, heptanol, hexanol, octanol, benzyl alcohol, phenol, ethanol, propanol, butanol, oleyl alcohol, dodecyl alcohol, octadecanol, triethylene glycol monomethyl ether, 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)ethyl succinate, or a combination thereof.

6. 6. A formulation according to any one of claims 1 to 5, having a loading of metal oxide nanocrystals in the range of 20 wt% to 80 wt% of the formulation.

7. Monofunctional acrylate and / or methacrylate monomers with high refractive index, such as benzyl acrylate, benzyl methacrylate (BA and BMA), ethylene glycol phenyl ether acrylate, ethylene glycol phenyl ether methacrylate (PEA and PEMA), 2-hydroxy-3-phenoxypropyl acrylate, 2-hydroxy-3-phenoxypropyl methacrylate (HPPA and HP 7. The formulation of any one of claims 1 to 6, further comprising 2-phenylmethylsulfonyl acrylate (PMA), 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 a combination thereof.

8. Di-, tri-, tetra-, and / or penta-functional acrylate and / or methacrylate monomers, such as 1,6-hexanediol diacrylate, 1,6-hexanediol di-methacrylate (HDDA and HDDMA), di(ethylene glycol) diacrylate, di(ethylene glycol) dimethacrylate (DEGDA and DEGDMA), ethylene glycol diacrylate, glycerol 1,3-diglycerolate diacrylate, tri(propylene glycol) diacrylate, tri(propylene glycol) diacrylate, tri(propylene glycol) diacrylate, 8. The formulation of any one of claims 1-7, further comprising an acrylate, trimethylolpropane triacrylate, trimethylolpropane tri-methacrylate (TMPTA and TMPTMA), trimethylolpropane ethoxylate triacrylate, trimethylolpropane ethoxylate tri-methacrylate (EOTMPTA and EOTMPTMA), 1,6-hexanediol ethoxylate diacrylate, pentaerythritol tetraacrylate (PETA), dipentaerythritol penta / hexaacrylate (DPHA), or a combination thereof.

9. 9. The formulation of any one of claims 1 to 8, further comprising a reactive diluent, such as 1-vinyl-2-pyrrolidone (NVP), N-vinylcaprolactam, 2-(2-vinyloxyethoxy)ethyl acrylate, 2-(2-vinyloxyethoxy)ethyl methacrylate, isobutyl acrylate, styrene (STY), 4-methylstyrene (4MS), 4-vinylanisole (4VA), and divinylbenzene (DVB), wherein the weight percentage of the reactive diluent is 25 to 70 wt % based on the total monomer content.

10. 10. The formulation of any one of claims 1 to 9, further comprising a di-, tri-, and / or tetra-functional thiol cross-linker, such as trimethylolpropane tris(3-mercaptopropionate).

11. 11. The formulation of any one of claims 1 to 10, further comprising a sulfur-containing resin and / or adhesive, such as commercially available sulfur-containing resins and / or adhesives, such as #18109, #18165, #6205 (NTT-AT), Lumiplus LP-1100, LPB-1102, LPJ-1102, LPS-1130 (Mitsubishi Gas Chemical Company), or a combination thereof.

12. A formulation according to any one of claims 1 to 11, further comprising a reactive organic dopant, for example phenanthrene (PhA) or 9-vinylcarbazole (NVCb), for example in a concentration range of 1 to 50 wt%.

13. 13. A formulation according to any one of claims 1 to 12, further comprising a surfactant or combination of surfactants, such as polyether modified siloxanes, fluorosurfactants, which are either non-reactive or reactive in acrylate monomer systems, wherein the concentration of said surfactant in the total formulation is in the range of 0.1 to 2.0 wt%, or in the range of 0.5 to 1.0 wt%.

14. scattering particles, such as titanium dioxide, aluminum oxide, silicon dioxide, and / or 14. A formulation according to any one of claims 1 to 13, optionally further comprising low and high refractive index polymer particles, wherein the scattering particle size is in the range of 100 to 400 nm and the concentration of said scattering particles in the total formulation is in the range of 0.1 to 30.0 wt % or 0.5 to 17.0 wt %.

15. 15. The formulation of any one of claims 1 to 14, further comprising a curing agent or photoinitiator, such as Irgacure 184, Irgacure 819, TPO, Ebercryl P39, and / or Ebercryl P115, wherein the concentration of said curing agent or photoinitiator in the total formulation ranges from 0.1 to 20 wt % or 1.0 to 4.0 wt % relative to the monomer content.

16. 16. A formulation according to any one of claims 1 to 15, which does not contain benzyl methacrylate (BMA) or trimethylolpropane triacrylate (TMPTA).

17. The viscosity of the formulation is Brookfield RVDV II+ (Brookfield RVDV II+) The formulation of claim 16, wherein the viscosity is in the range of 5 to 100 cP when measured at 25°C using a cone and plate viscometer, and the preferred viscosity for inkjet printing at 25°C is 5 to 20 cP, and if cartridge heating is applicable, the viscosity at 25°C can be 15 to 100 cP when the cartridge temperature is 35 to 100°C, or the viscosity of the formulation 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, and for deposition methods other than inkjet printing the viscosity can be in the range of 100 cP to 1,000 cP, 1,000 cP to 5,000 cP, 5,000 cP to 12,000 cP when measured at 25°C.

18. 18. The formulation of claim 17, wherein the nanocrystal loading is 35-40%, 40-45%, 45-50%, 50-55%, 55-60%, 60-65%, or 65-70% by weight.

19. 19. A formulation according to any one of claims 17 to 18, wherein the refractive index of the formulation is from 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 1.76 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, or 1.90 to 1.92, or 1.92 to 1.94 at 589 nm, as measured with an Abbe refractometer.

20. 20. The formulation of any one of claims 17 to 19, wherein the surface tension of the formulation is within the range of 20 to 25 dynes / cm, 25 to 30 dynes / cm, 30 to 35 dynes / cm, or 35 to 40 dynes / cm, as measured at 25°C using a Rame-Hart surface tensiometer.

21. 21. A formulation according to any one of claims 17 to 20, wherein the %T of the formulation 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% at visible wavelengths (400-700nm).

22. Dimatrix DMC (Dimatix DMC), Fujifilm SG1024 / MA ( 22. The formulation of any one of claims 1 to 21, which is inkjet printable, e.g. small droplets of the formulation, which can be ejected from a printhead type such as a Fujifilm SG1024 / MA or a Konica Minolta KM1024i, at a drop speed of 3 to 9 m / s and a small drop volume of 6 to 40 pL.

23. 23. A nanocomposite film prepared from a process comprising applying the formulation of any one of claims 1 to 22 to a surface via spin-coating, slot-die coating, screen-printing, inkjet printing, nanoimprinting, photopatterning, 3D printing, dip-coating, draw-bar coating, roll-to-roll printing, spray-coating, dispensing, volume casting, screen-printing, or any combination thereof, and optionally curing the applied formulation.

24. The formulation is exposed to 0.1 to 10 J / cm under an LED source of UV having a wavelength of 365 nm, 385 nm, 395 nm, or 405 nm, or through a mercury "D", "H", and / or "V" lamp. ２ , or 0.5 to 2 J / cm ２ 24. A nanocomposite comprising the cured or partially cured formulation of any one of claims 1 to 23, which is cured or partially cured through UV irradiation at a UV dose in the range of

25. 25. The nanocomposite of claim 24, which is a film having a thickness ranging from 50 nanometers to 100 micrometers, or from 0.5 micrometers to 20 micrometers.

26. 26. The nanocomposite of any one of embodiments 23-25, wherein the %T of the cured or partially cured nanocomposite at a thickness of less than 10 microns 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% at a visible wavelength of 400 nm to 700 nm.

27. The cured or partially cured nanocomposite has a densitometric average molecular weight (MgO) of 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 1.76-1.78, or 1.78-1.

27. The nanocomposite of any one of embodiments 23 to 26, having a refractive index of 1.80, or from 1.80 to 1.82, or 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.

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