Display device using quantum dots and inkjet printing technology thereof

Abstract

Ink compositions for forming quantum dot-containing films are provided. Methods of forming quantum dot-containing films via inkjet printing and photonic devices incorporating quantum dot-containing films as light emitting layers are also provided. The ink compositions include quantum dots, a di(meth)acrylate monomer or a combination of a di(meth)acrylate monomer and a mono(meth)acrylate monomer, and one or more multifunctional crosslinkers.

Description

[0001] References to related applications

[0002] This application claims priority to U.S. Provisional Patent Application No. 62 / 407,449, filed October 12, 2016; U.S. Provisional Patent Application No. 62 / 413,910, filed October 27, 2016; and U.S. Provisional Patent Application No. 62 / 440,216, filed December 29, 2016, the entire contents of which are incorporated herein by reference.

[0003] Overview

[0004] Liquid crystal display (LCD) technology continues to evolve in improving the end-user experience. One aspect of improving the end-user experience is expanding the color gamut of LCD devices.

[0005] Accordingly, quantum dot (QD) technology has been explored to expand the color gamut of LCD devices. Typically, as will be discussed in more detail later in this article, various technical solutions are based on improvements to LCD device assemblies containing polymer sheets or rods in which QDs are embedded.

[0006] The inventors have recognized that inkjet printing technology can be used to provide innovative QD color enhancement devices (CEDs), as well as to provide the introduction of QDs into sub-assemblies of LCD devices and into LCD panel sub-assemblies of LCD devices.

[0007] Overview

[0008] An ink composition for forming a film containing sub-dots is provided. A method for forming the film via inkjet printing and a light-emitting device for introducing said film are also provided.

[0009] One embodiment of a method for forming a light-emitting layer in a photonic device includes: inkjet printing a layer of ink composition onto a device substrate of the photonic device and curing the ink composition. One embodiment of the ink composition comprises: 70% to 96% by weight of a di(meth)acrylate monomer or a combination of a di(meth)acrylate monomer and a mono(meth)acrylate monomer; 4% to 10% by weight of a multifunctional (meth)acrylate crosslinking agent; and 0.1% to 5% by weight of quantum dots, wherein the ink composition has a viscosity in the range of 2 cp to 30 cp at 22°C and a surface tension in the range of 25 dynes / cm to 45 dynes / cm at a temperature in the range of 22°C to 40°C.

[0010] One embodiment of a photonic device includes: a photonic device substrate; and a crosslinked polymer film on the photonic device substrate, the crosslinked polymer film comprising: 70% to 96% by weight of a polymer chain comprising a polymeric di(meth)acrylate monomer or a combination of polymeric di(meth)acrylate monomers and mono(meth)acrylate monomers; 4% to 10% by weight of a polymeric multifunctional (meth)acrylate monomer crosslinking the polymer chain; and 0.1% to 5% by weight of quantum dots. Brief description of the attached diagram

[0011] A better understanding of the features and advantages of this disclosure will be obtained by referring to the accompanying drawings, which are intended to illustrate and not limit the teachings. The drawings are not necessarily drawn to scale, and in the drawings, the same numbers may describe similar parts in different views. The same numbers with different letter suffixes may indicate different configurations of similar parts.

[0012] Figure 1A This is a schematic diagram illustrating various layers that may be included in one embodiment of an LCD display device. Figure 1B This is a schematic diagram illustrating various layers that may be included in another embodiment of an LCD display device.

[0013] Figure 2A This is a schematic diagram of the upper layer of an LCD device including a QD color filter. Figure 2B for Figure 2A A cross-sectional view of the upper layer of the LCD device, showing the configuration of the QD color filter. Figure 2C The illustration shows the printing of a QD color filter, which contains scattering nanoparticles (represented by hollow circles) in its green, red, and blue subpixels. Figure 2D It indicates that in Figure 2C The implementation scheme of QD color filter is to print a blocking layer or a planarization layer. Figure 2E It indicates the use of Figure 2D LCD devices with QD color filters.

[0014] Figure 3A This is a schematic diagram of the upper layer of an LCD device, where the layer stack does not include local cutoff filters in the sub-pixel units. Figure 3B According to Figure 3A A cross-sectional side view of the upper layer of an LCD device, which contains blue, green, and red sub-pixels in a QD color filter. Figure 3C The absorption spectrum of the global cutoff filter is shown, with its absorption wavelength shorter than the blue emission wavelength of the device. Figure 3D A cross-sectional side view of one embodiment of a QD color filter is shown, which includes a local filter layer adjacent to the QD-containing layer in the sub-pixel. Figure 3EThe absorption spectrum of the red subpixel-specific cutoff filter layer is shown; the absorption spectrum of the red emission QD in the light-emitting layer is shown; and the emission spectrum of the red emission QD in the light-emitting layer for the red subpixel is shown. Figure 3F For similar Figure 2A The diagram shows the upper layer of the LCD device, but unlike the previous diagram, this stack also includes a global cutoff filter layer. Figure 3G According to Figure 3F A cross-sectional side view of the upper layer of an LCD device, which contains blue, green, and red sub-pixels in a QD color filter. Figure 3H The absorption spectrum of the global cutoff filter layer is shown; the absorption spectrum of the red subpixel-specific local cutoff filter layer is shown; the absorption spectrum of the red emission QD in the light emission layer is shown; the emission spectrum of the red emission QD in the light emission layer for the red subpixel is shown; and the emission spectrum of the blue emission QD in the blue light emission layer is shown (or, the blue light emission spectrum transmitted through the blue BLU of the blue subpixel is shown).

[0015] Figure 4A A method for inkjet printing local filter layers in subpixel units of a QD color filter is shown. Figure 4B A method for inkjet printing a light-emitting layer containing QD in a sub-pixel unit of a QD color filter is shown.

[0016] Figure 5 A cross-sectional side view of a layer with content sub-points positioned between two protective layers is shown for a color enhancement device.

[0017] Figure 6 This is a schematic exploded perspective view showing the components of an LCD device.

[0018] Figure 7A A cross-sectional side view of a substrate tray used for inkjet printing multiple device substrates is shown. Figure 7B It shows Figure 7A A top view of the substrate tray.

[0019] Figure 8 A top view of one embodiment of a side-lit CED with discontinuous content sub-dots is shown.

[0020] Figure 9 It shows Figure 8 A cross-sectional side view of the CED.

[0021] Figure 10 A cross-sectional side view of another embodiment of a side-lit CED with discontinuous content sub-points is shown.

[0022] Figure 11A cross-sectional side view of one embodiment of a side-lit CED with discontinuous layers containing scattering nanoparticles and individual content sub-dots is shown.

[0023] Figure 12 It shows Figure 11 The CED has plasma-scattering nanoparticles in the layer of said content sub-dots.

[0024] Figure 13 A cross-sectional side view of an embodiment of a side-lit CED is shown, comprising a continuous layer containing scattering nanoparticles with a thickness variable along its length and individual content sub-dots.

[0025] Figure 14 A cross-sectional side view of one embodiment of a side-lit CED having a continuous layer containing both quantum dots and scattering nanoparticles and whose thickness varies along its length is shown.

[0026] Figure 15 A cross-sectional side view of an embodiment of a side-lit CED is shown, comprising a continuous layer containing scattering nanoparticles of uniform thickness along its length and individual content sub-dots.

[0027] Figure 16 A cross-sectional side view of an embodiment of a side-lit CED having a continuous layer containing both quantum dots and scattering nanoparticles with uniform thickness along its length is shown.

[0028] Figure 17 A cross-sectional side view of one embodiment of a backlit CED with a layer of discontinuous content sub-dots is shown.

[0029] Figure 18 A cross-sectional side view of one embodiment of a backlit CED with discontinuous layers containing scattering nanoparticles and individual content sub-dots is shown.

[0030] Figure 19 A cross-sectional side view of an embodiment of a backlit CED is shown, comprising a continuous layer of scattering nanoparticles with uniform thickness along its length and individual content sub-dots.

[0031] Figure 20 A cross-sectional side view of one embodiment of a backlit CED having a continuous layer containing both quantum dots and scattering nanoparticles with uniform thickness along its length is shown.

[0032] Figure 21 A cross-sectional side view of one embodiment of a backlit CED is shown, comprising a continuous layer of scattering nanoparticles and individual content sub-dots, wherein the layer of scattering nanoparticles has thickness modulation along its length and the layer of content sub-dots has optional thickness modulation along its length.

[0033] Figure 22 This is a schematic diagram of a method for inkjet printing a layer containing quantum dots and scattering nanoparticles on a device substrate.

[0034] Figure 23 This is a schematic diagram of a method for forming a sealing layer on a substrate, optionally and a barrier layer.

[0035] Figure 24 A schematic diagram of a method for printing one or more CED layers between sealing dams of a sealing layer and then sealing the CED layer.

[0036] Figure 25 Tables showing the structure, room temperature viscosity, and room temperature surface tension of cyclic trimethylolpropane acetal acrylate, alkoxylated tetrahydrofurfuryl acrylate, 2-phenoxyethyl acrylate, 1,3-butanediol diacrylate, and 2-(2-ethoxyethoxy)ethyl acrylate.

[0037] Figure 26 A flowchart of a method for preparing an ink composition containing QD is shown.

[0038] Figure 27 The following is a formulation table of the two basic ink compositions as described in Example 1.

[0039] Figure 28 The table shows the formulations of two QD-containing ink compositions as described in Example 1, along with their room temperature surface tension and viscosity.

[0040] Figure 29A The emission spectra of a layer containing silver nanoparticle plasma scatterers in combination with green emitting QDs and a layer containing only green emitting QDs without any silver nanoparticle plasma scatterers are shown.

[0041] Figure 29B The emission spectra of a layer containing silver nanoparticle plasma scatterers in combination with red emitting QDs and a layer containing only green emitting QDs without any silver nanoparticle plasma scatterers are shown.

[0042] Detailed Explanation

[0043] Ink compositions for forming QD-containing films are provided. Methods for forming QD-containing films via inkjet printing and photonic devices incorporating QD-containing films are also provided. QD-containing films can be incorporated as light-emitting layers into various optoelectronic devices. While the following description illustrates the use of QD-containing films as color filter layers and color enhancement layers in devices such as LCDs or organic light-emitting diodes (OLEDs), QD-containing films can be incorporated into other devices that include QD-containing light-emitting layers.

[0044] Display devices with color filters incorporating QD layers

[0045] Figure 1A For illustrative purposes, various layers that may be included in an LCD display device are shown. For various display devices, such as various LCD devices, and for certain types of organic light-emitting diode (OLED) devices, light is guided from a white light source located behind each sub-pixel of the color filter array. Sub-pixels may be, but are not limited to, red (R) sub-pixels, green (G) sub-pixels, and / or blue (B) sub-pixels. For LCD devices, the light source may be a backlight that simultaneously illuminates a plurality of sub-pixels in the color filter array at a common brightness, wherein the brightness may be adjusted based on the image to be displayed. The light transmitted through each sub-pixel of the color filter array may be further modulated by a corresponding liquid crystal filter associated with each sub-pixel of the color filter array. The liquid crystal filter may be controlled, for example, by transistor circuitry. In the case of OLED devices, the light supplied to each sub-pixel of the color filter array typically originates from a white OLED device, and the brightness of each sub-pixel is modulated by transistor circuitry. For various embodiments of LCD or OLED devices, each sub-pixel of the color filter array contains a filter medium that transmits light only within a defined electromagnetic wavelength bandwidth associated with the sub-pixel color. Conventional color filter arrays can be fabricated using techniques such as photolithography, a complex process requiring many individual steps such as blanket coating, exposure, and development to create the light-blocking "black matrix" material in / between the sub-pixels, as well as individual color filter material deposition steps (e.g., one each for R, G, and B). Although Figure 1A An indium tin oxide (ITO) layer is indicated, which in various embodiments may be coated on the polarizer surface facing the liquid crystal, but many embodiments of the LCD display device do not include an ITO coating on the polarizer. The device may have an anti-glare layer to reduce glare caused by ambient light.

[0046] Figure 1B For illustrative purposes, various layers may be included in an LCD display device according to this teaching. Figure 1B In the devices, Figure 1AThe color filter shown has been replaced by a color filter layer made of QD. QDs are small crystalline particles that absorb incident radiation having a first wavelength or a first wavelength range and convert the energy of that radiation into light with a different wavelength or a different wavelength range, which is emitted from the QD and within a very narrow portion of the spectrum. Therefore, by introducing QDs of appropriate size and material into the light-emitting device layer at appropriate concentrations and ratios, the layer can be designed to alter the absorption and / or emission spectrum of the photonic device introduced into the layer. Thus, QD-containing color filter layers are so named because they "filter" incident light having a first wavelength or wavelength range, such as ultraviolet or blue light, by converting at least a portion of the incident light into light with a different wavelength or wavelength range, such as red and / or green light. On the first side of the QD-containing color filter, as shown... Figure 1B As shown, a polarizer layer may exist.

[0047] LCD devices can also utilize an anti-photoluminescence layer in conjunction with a color filter containing QDs (referred to herein as a QD color filter). Since the QD-based color filter subpixels are located in front of the display, it is desirable to prevent ambient light from acting as an excitation source for the QDs in the color filter layer. Accordingly, various embodiments of LCD devices utilize various local and global filter layers as anti-photoluminescence layers. Similarly, this filter layer can also be used to prevent excessive blue light (which has not yet been absorbed and converted by the QD layer) from being transmitted and thus reducing the color gamut of the display. Furthermore, as will be described in more detail herein, the QD-containing layers of various embodiments of the QD color filter and various anti-photoluminescence layers for such devices can be manufactured using inkjet printing.

[0048] Figure 2A for Figure 1B A schematic diagram of the upper layer of an LCD device of the type shown. Figure 2B This is a cross-sectional view of the upper layer of the LCD device. (For example, regarding...) Figure 1B As described herein, a polarizer layer may exist on the first side of the QD-containing layer of the QD color filter. In accordance with the provisions of this document... Figure 1B , Figure 2A , Figure 2B , Figure 2E , Figure 3A , Figure 3B , Figure 3F and Figure 3G In various embodiments of color filters incorporating QD (Quantity Diode) generally illustrated, a conductive film such as an ITO film may be coated on the polarizer layer, while in other embodiments, the device may not require an ITO coating. In various embodiments of LCD devices utilizing conductive coatings, other conductive transparent materials may also be used, such as, but not limited to, fluorine-doped tin oxide (FTO), doped zinc oxide, and graphene, or combinations of such materials. Figure 2BAs shown, the QD color filter comprises multiple sub-pixel units defined by sub-pixel embankments (depicted in bold black). Subpixels formed within these sub-pixel units include red subpixels (in...). Figure 2B (represented by "R"), green subpixels (in) Figure 2B (represented by "G" in the text) and blue subpixels (in the text) Figure 2B (Represented by "B" in the original text). Each red subpixel includes a red emitting layer containing red emitting QDs dispersed in a polymer matrix. Similarly, each green subpixel includes a green emitting layer containing green emitting QDs dispersed in a polymer matrix. In some embodiments of an LCD device in which the BLU is ultraviolet light, each blue subpixel includes a blue emitting layer containing blue emitting QDs in a polymer matrix. In other embodiments of an LCD device in which the BLU is blue light, the blue subpixels in the QD filter do not need to contain QDs, but may optionally contain a polymer matrix that at least partially transmits blue light from the BLU. The polymer matrix in the subpixel is capable of transmitting light of at least some portion of the visible spectrum. For example, the BLU may consist of one or more blue LEDs.

[0049] exist Figure 2B In LCD devices, the anti-photoluminescence layer is provided in the form of a global cutoff filter layer and a local cutoff filter layer. More information about the structure of the global and local cutoff filter layers (also called global filter layers and local filter layers) can be found at [link to relevant documentation]. Figure 3A , 3B 3F and 3G are provided in the descriptions accompanying them below.

[0050] In addition to QDs, the light-emitting layer of a subpixel may also contain scattering nanoparticles (SNPs), which can be geometrically scattering nanoparticles (GSNPs), plasmon scattering nanoparticles (PSNPs), or a combination thereof. It should be noted that while PSNPs and GSNPs typically have at least one nanometer-scale dimension—that is, at least one dimension no larger than about 1000 nm—the nanoparticles do not need to be spherical. For example, nanoparticles can be elongated particles such as nanowires, or irregularly shaped particles. Such scattering nanoparticles can also be contained in the matrix material of a blue subpixel that does not contain any QDs. Scattering by GSNPs is achieved through refraction at the particle surface. Examples of GSNPs include metal oxide nanoparticles, such as zirconium oxide (i.e., zirconium oxide), titanium oxide (i.e., titanium dioxide), and aluminum oxide (i.e., aluminum oxide). PSNPs are characterized by incident light exciting electron density waves in the nanoparticles, which generates a localized oscillating electric field extending from the surface of the nanoparticles. In addition to the scattering effect of the particles, if the PSNP is adjacent to one or more QDs, this electric field can couple to the QDs, thereby enhancing the absorption of the QD layer. Examples of PSNPs include metallic nanoparticles, such as silver nanoparticles.

[0051] Figure 2C An example of a QD color filter 160 is shown, which includes GSNPs that can be formed into a plurality of sub-pixel units 115 formed in a substrate 110 using inkjet printing. Figure 2C As shown, the printable ink composition (CFI) containing green QD is... G Ink compositions containing blue QD (CFI) B ) and ink compositions containing red QD (CFI) R To form the green, blue, and red light-emitting layers of the QD color filter 160, respectively. For example... Figure 2C As generally indicated, various QD inks may contain SNPs (represented by hollow circles), which can be introduced into the green, red, and blue subpixels. (e.g.) Figure 2C As shown in the diagram, green QDs are represented by smaller solid circles, and red QDs by larger solid circles. SNPs provide enhanced light absorption and extraction by acting as light scattering centers within the polymer matrix. Incorporating SNPs in combination with QDs can increase the color conversion efficiency of QD-containing subpixels by increasing photon scattering within the light-emitting layer, resulting in more interaction between photons and QDs, and thus QDs absorbing more light.

[0052] In embodiments of QD color filters that include blue emission QDs in blue subpixels, SNPs (e.g., GSNPs) may also be included in these subpixels. However, even blue subpixels without QDs may include SNPs dispersed in a polymer matrix to provide isotropic blue light emission from the blue subpixels, which is equal to or nearly equal to the isotropic red and green light emission provided by the red and green subpixels, such that the optical appearance of the emitted blue light (e.g., hazy and specular emission) is similar to the optical appearance of the emitted red and green light. However, some embodiments of the light-emitting layer do not include SNPs to avoid undesirable scattering of ambient light in the subpixels.

[0053] QDs and (if present) GSNPs and / or PSNPs can be introduced into the light-emitting layer of a subpixel by including them in an ink composition, inkjet printing the ink composition to deposit them as layers in subpixel units, and drying and / or curing the printed ink composition. For example, depending on the type of scattering, an effective scattering nanoparticle size in the range of about 40 nm to about 1 μm can be selected for the jettable ink. GSNPs are generally larger than PSNPs, and both types of particles are generally larger than QDs. By way of example only, in various embodiments of the ink composition and the layer formed therefrom, the effective size of GSNPs is in the range of about 100 nm to about 1 μm, while the effective size of PSNPs is in the range of about 10 nm to about 200 nm.

[0054] Figure 2D A method for printing a polymer layer on various embodiments of a QD color filter 160 is generally illustrated. According to this teaching, a polymer layer 170 can be printed after forming the QD-containing light-emitting layer of the QD color filter. According to this teaching, the polymer layer 170 can be a planarization layer. In various embodiments, the polymer layer 170 can be a planarization layer, which can also function as a protective layer. For various embodiments of the QD color filter, as will be discussed... Figure 2E In more detail, polymer layer 170 can be printed onto an inorganic barrier layer. As will be described in more detail herein, polymer layer 170 can be formed from a polymer-based ink composition, which, upon subsequent curing or drying, forms polymer layer 170. The thickness of polymer layer 170 can be, for example, between about 1 μm (micrometer) and about 5 μm (micrometer). Figure 2D As generally illustrated, a surface topology can exist that combines factor pixel unit structures with, for example, meniscus formation appearing in sub-pixel units. Therefore, inkjet printing can be performed to compensate for changes in surface topology, for example, by printing more polymer-based ink composition on areas with depressions and less polymer-based ink composition on areas that are raised relative to the depressions.

[0055] This teaching can be used to form Figure 2D In various embodiments of the polymer-based ink composition of polymer layer 170, particles of various shapes and materials may be added to the ink composition to provide refractive index modulation of the polymer layer formed on the QD-containing sub-pixels. In various embodiments of such ink compositions forming polymer films, metal oxide nanoparticles, such as zirconium oxide, aluminum oxide, titanium oxide, and hafnium oxide, with sizes, for example, between about 5 nm and about 50 nm, may be added to the ink. For various embodiments of such ink compositions forming polymer films, graphene nanostructures, such as graphene nanoribbons and graphene microflakes, may be added to the ink composition to significantly reduce water vapor permeation through the polymer layer. According to this teaching, graphene microflakes may have dimensions, for example, a thickness between about 0.1 nm and about 2 nm and a diameter between about 100 nm and about 1 μm (micrometer), while graphene nanoribbons may have dimensions, for example, a thickness between about 0.1 nm and about 10 nm and a length between about 1 nm and about 20 nm. The amount of various graphene nanoparticles used in the ink compositions of this teaching may be between about 0.1% and 1.0%.

[0056] Figure 2E This generally indicates (for example, such as) Figure 1BThe figure shows a portion of an LCD device, depicting a planarization layer 170 oriented toward a polarizer 160, for which an ITO layer, as previously described, may be optional. In various embodiments of the QD filter 160, the planarization layer may be, for example, a polyethylene terephthalate (PET) film, an acrylate-based polymer film, etc. It is known that QDs embedded in the QD-containing sub-pixels of the QD filter 160 degrade upon exposure to atmospheric gases such as water vapor, oxygen, and ozone. Therefore, in various embodiments of the QD filter, the polymer layer 170 may be coupled to an inorganic barrier layer that protects the QD-containing layer from the intrusion of water vapor, oxygen, and / or ozone. The inorganic barrier layer, which may be disposed above or below the polymer layer 170, may be composed of inorganic materials such as metal oxides, metal nitrides, metal carbides, metal oxynitrides, metal boron oxides, and combinations thereof. For example, the inorganic barrier layer may be composed of materials such as silicon nitride (SiN). x ), alumina (Al2O3), titanium dioxide (TiO2), hafnium oxide (HfO2) or silicon oxynitride (SiO2) materials x N y Layer 170 may be composed of a first barrier layer consisting of at least one inorganic barrier material as described herein, followed by a second polymer layer. If present, the polymer planarization layer and the barrier layer should be able to transmit light in the visible region of the electromagnetic spectrum. The polymer protective layer may be deposited using inkjet printing, as illustrated in U.S. Patent Publication 2016 / 0024322.

[0057] To prevent ambient light from exciting quantum dots, three implementation schemes of CED are proposed: (1) a CED containing only a global cutoff filter; (2) a device containing only a local cutoff filter; and (3) a device containing both global and local cutoff filters.

[0058] Some implementations of LCD devices will include a global cutoff filter layer without any local cutoff filters. Figure 3A and 3B One such device is schematically shown in the figure. Figure 3A This is a schematic diagram of the upper layer of an LCD device. Figure 3B This is a cross-sectional side view of the upper layer, which includes blue, green, and red sub-pixels in the QD color filter layer. A global cutoff filter can be deposited on either side of the glass substrate. Ambient light with wavelengths shorter than blue emission is blocked from entering the QD layer and therefore will not excite the red and green QDs. This global cutoff filter layer can be continuous and unpatterned and can be disposed on either side of the QD color filter substrate. Ideally, the global cutoff filter layer has high optical performance and a steep cutoff filter characteristic.

[0059] Figure 3D A cross-sectional side view of one embodiment of a QD color filter is shown, which includes a local filter layer disposed between the substrate and the light-emitting surface of the QD-containing layer in each sub-pixel unit. These local filter layers are used to filter out ambient light incident on the device; otherwise, ambient light would enter the QD-containing layer and be absorbed by the QDs, resulting in unwanted photoluminescence and degrading the optical quality of the LCD. Through the same mechanism, these local filters also filter out any excess blue light from the BLU that is not absorbed by the QD layer, which would otherwise cause reduced color saturation and color gamut of the display. Figure 3E As shown, the local filter layer (LF) acts as a sub-pixel-specific cutoff filter; it absorbs radiation with wavelengths lower than the emission wavelength of the QD in the light-emitting layer containing the QD and transmits radiation with wavelengths lower than and higher than the emission wavelength of the light-emitting layer containing the QD. Figure 3E The diagram illustrates a local filter layer for the red sub-pixel. This local filter layer contains a light absorber with appropriate light absorption properties. Therefore, for the red sub-pixel (LF... R The local filter layer of the red emitter (LF) will contain a light absorber that absorbs radiation with wavelengths lower than the red emission wavelength of the red emitter QD in the red emitter subpixel and transmits radiation with wavelengths lower than and higher than the red emission wavelength of the red emitter QD in the red emitter subpixel. Similarly, for the green subpixel (LF... G The local filter layer of the green sub-pixel will contain a light absorber that absorbs radiation with wavelengths lower than the green emission wavelength of the green emitting sub-pixel and transmits radiation with wavelengths lower than and higher than the green emission wavelength of the green emitting sub-pixel. Furthermore, if a blue QD is used, then for the blue sub-pixel (LF... B The local filter layer of the blue subpixel will contain a light absorber that absorbs radiation with wavelengths lower than the blue light emission wavelength of the blue emitting subpixel and transmits radiation with wavelengths below and above the blue light emission wavelength of the blue emitting subpixel. If the blue subpixel does not contain a QD, the local filter layer can be omitted, in which case the subpixel unit corresponding to the blue subpixel can be completely filled with a matrix material that is optically transparent to blue light. The local filter can be deposited using, for example, inkjet printing; the light-absorbing material is deposited into the subpixel unit before the QD-containing light-emitting layer of the QD filter is deposited in the subpixel unit and then dried / cured. In this way, two discrete layers can be formed within the subpixel unit, wherein the local cut-off filter layer faces the outside of the device after assembly and thus protects the QD filter layer from unwanted excitation.

[0060] exist Figure 2BIn one variant of the LCD shown, local filter layers may be formed below their respective sub-pixel units, rather than within those sub-pixel units. In this variant, the local filter layers can be patterned above the sub-pixel units using, for example, photolithography.

[0061] In some implementations of LCD devices, a global cutoff filter layer is combined with a local cutoff filter layer. In such devices, ambient light with wavelengths shorter than the blue emission wavelength of the display device is blocked by the global cutoff filter layer. However, light with wavelengths longer than the blue emission wavelength but shorter than the emission wavelength of the QD at the corresponding sub-pixel location can still excite the QD. A local cutoff filter that blocks only this specific portion of the spectrum can be combined with a global cutoff filter to eliminate (or significantly reduce) the excitation of the QD by ambient light. Simultaneously, the local cutoff filter with the aforementioned properties will block excess blue light from the BLU that has not been absorbed by the QD color filter. This method enhances the color saturation and color gamut of the display. Figure 3F and 3G The diagram illustrates one embodiment of a display device incorporating a local cutoff filter layer and a global cutoff filter layer. Figure 3H The spectral function of the system is shown in the figure.

[0062] Figure 3F This is a schematic diagram of the upper layer of an LCD device. Figure 3G This is a cross-sectional side view of the upper layer, which includes blue, green, and red sub-pixels in the QD color filter. In this embodiment of the LCD device, the QD color filter has... Figure 3D The same structure is shown, and the global cutoff filter layer covers all sub-pixel units. As discussed above, the global cutoff filter layer acts as an additional filter for ambient incident light; it absorbs radiation with wavelengths lower than the device's shortest emission wavelength, for example, radiation with wavelengths lower than the device's blue emission wavelength. Figure 3F , 3G In the LCD implementation shown in 3H, the red subpixel includes a local cutoff filter layer that acts as a bandpass filter for ambient incident light. Similar local filter layers may be included in the green and / or blue subpixels.

[0063] In addition to providing local filters as separate layers from the QD-containing layers in the QD color filter, or as an alternative, light-absorbing materials can be introduced into the QD color filter layer by including them in a QD-containing ink composition, inkjet printing the ink composition as a QD-containing layer in a sub-pixel unit, and curing the printed ink composition. It should be understood that, although not depicted herein, the light-absorbing material, QD, and optionally any GSNP and / or PSNP can be included in a single ink composition and printed as a single layer in a sub-pixel unit, wherein the light absorber and QD are uniformly distributed. However, in such embodiments, it may be desirable to select the light-absorbing material and polymer matrix material such that they do not completely prevent the transmission of blue light. Suitable light absorbers for inclusion in the local filter layer include organic dye molecules, such as azo dyes, inorganic pigments, and combinations thereof.

[0064] Figure 2C The image schematically illustrates a method for inkjet printing a QD color filter comprising multiple green, red, and blue subpixels, thereby directly printing a green filter ink composition CFI into subpixel units targeting the green subpixels using a first inkjet printing nozzle. G The blue filter ink composition CFI is directly printed into the sub-pixel units targeting the blue sub-pixel using a second inkjet printing nozzle. B The third inkjet printing nozzle is used to directly print the red filter ink composition CFI into the sub-pixel unit targeting the red sub-pixel. R Alternatively, different color subpixels can be printed sequentially using the same inkjet printing nozzle. Each color filter ink composition contains its corresponding color emission QD in an organic polymer binder material, an organic solvent, or a mixture thereof. The curable organic polymer binder material will cure to form a polymer matrix material and may contain a variety of organic monomers, oligomers, and / or polymers, which will be discussed in more detail below. In addition, the color filter ink composition may contain a crosslinking agent, a photoinitiator, or both.

[0065] Figure 4A and 4B The diagram schematically illustrates a method for inkjet printing a QD color filter with a local filter layer, thereby printing the local filter layer in the sub-pixel unit before printing the light-emitting layer containing the QD. Figure 4A As shown, a green local filter ink composition (LFI) is directly printed onto a sub-pixel unit targeting a green sub-pixel using a first inkjet printing nozzle (or a first set of nozzles). G The blue local filter ink composition LFI is directly printed into the sub-pixel unit targeting the blue sub-pixel using a second inkjet printing nozzle (or a second set of nozzles). BThe red local filter ink composition LFI is directly printed into the sub-pixel unit targeting the red sub-pixel using a third inkjet printing nozzle (or a third set of nozzles). R Alternatively, different colors of subpixels can be printed sequentially using the same inkjet printing nozzle (nozzle group). Each local filter ink composition contains its corresponding light-absorbing material in a binder material, solvent, or mixture thereof. The curable binder material will cure to form a matrix material and may contain various organic monomers, oligomers, and / or polymers, which will be discussed in more detail below. Additionally, the local filter ink composition may contain a crosslinking agent, a photoinitiator, or both. Once the subpixel-specific local filter layer is formed at the bottom of its respective subpixel unit, a light-emitting layer containing QD can be printed on the cured or dried local filter layer, such as... Figure 4B As shown in the diagram. After the final assembly of the display, the color filter substrate faces outwards while the layer containing the QD faces inwards.

[0066] In various alternative methods of printing layers containing QD and light-absorbing materials, a two-layer structure is produced by initially applying (e.g., inkjet printing) a single ink composition containing a mixture of QD and light-absorbing material as a monolayer and drying it in a manner that separates the layer containing the light-absorbing material from the layer containing the QD. For example, if the QD is terminally capped by long carbohydrate ligands, they can be phase-separated with a suitable solvent before the remaining portion of the ink composition containing the light-absorbing agent dries. Alternatively, the solubility of the light-absorbing material can be selected such that the material (or the matrix to which it is dissolved) segregates first due to the solubility limit of the material.

[0067] Color enhancement layer with QD

[0068] The inventors have recognized the use of inkjet printing technology to provide innovative quantum dots (QDs)-containing photonic devices (CEDs). Various CEDs taught in this invention comprise quantum dots dispersed in a matrix. CEDs can be formed as continuous or discontinuous inkjet-printed layers using inkjet-printable ink compositions containing QDs. Therefore, the composition, geometry, and placement of the CED can be precisely “fine-tuned” for various device applications. By introducing QDs of appropriate size and material into the CED at suitable concentrations and ratios, the CED can be designed to alter the absorption and / or emission spectra of the photonic device to which the CED is introduced.

[0069] Figure 5The figure schematically depicts a cross-sectional view of a basic embodiment of a CED. The CED includes a QD-containing layer 572 containing a plurality of QDs 580, 590 in a matrix 585, such as a polymer matrix. The QD-containing layer 572 may optionally be located between first and second protective layers 574A and 574B, respectively. As shown, the QD-containing layer 572 has a plurality of green emitting QDs 580 shown as smaller spheres and a plurality of red emitting QDs 590 shown as larger spheres. Figure 5 As shown, green emitting QD 580 and red emitting QD 590 are dispersed throughout the matrix 585, which may be, for example, a polymer matrix capable of transmitting light in the visible spectrum. Furthermore, considering the sensitivity of QDs to atmospheric gases such as water vapor, oxygen, and ozone, first and second protective layers 574A and 574B provide protection for the QDs embedded in the QD-containing layer 572. In various embodiments of the CED, the first and second protective layers 574A and 574B may be polymer films, such as polyethylene terephthalate (PET), acrylate-based polymer films, etc., or inorganic barrier layers, or a combination of both. Like the QD matrix 585, the protective film needs to be capable of transmitting light in the visible spectrum.

[0070] Depending on the device to which they are introduced, the CEDs of this teaching can enhance the end-user's visual experience by increasing the color gamut of the light output by the device; and / or improve the device's efficiency to provide the end-user with improved optical clarity and brightness. Similarly, the layer can also improve the absorption efficiency of radiation incident on the device. For example, a QD-containing layer can be inkjet-printed onto the surface of a photovoltaic cell, causing a portion of the radiation incident on the cell to be converted into wavelengths that are more effectively absorbed by the cell's photoactive materials. For instance, blue and / or ultraviolet (UV) light incident on a QD-containing layer in a silicon solar cell can be absorbed by the QD and emitted as red light, which will be more effectively absorbed by silicon. In photovoltaic cells, QD-containing layers can be printed directly onto photoactive materials or onto the surface of other components such as anti-reflective coatings or electrodes.

[0071] In LCD devices, layers containing QD can be printed directly onto the light guide surface or onto the surface of another component such as a reflector, diffuser, or polarizer. Figure 6An exploded perspective view of one embodiment of an LCD device 650 in which a CED can be introduced is generally illustrated. The LCD device 650 may have an LCD panel 652. The LCD panel 652 itself may consist of a plurality of component layers, which may include, for example, but not limited to, thin-film transistor (TFT) layers, liquid crystal layers, color filter array (CFA) layers, and linear polarizers. Additional component layers may include another polarizer 654, first and second brightness enhancement films 656A and 656B, respectively, and a reflector film 658. The LCD device 650 includes a light guide plate 660, which may include a plurality of LED devices 662 located near the ends of the light guide plate 660 as a source of light that can propagate through the light guide plate 660. For various LCD devices, the LED devices associated with the light guide plate may be white or blue LED sources, but as will be discussed later herein, for the LCD device 650, the plurality of LED devices 662 may be blue emitting LEDs having an emission line of, for example, but not limited to, 445 nm.

[0072] Multiple device layers can be simultaneously or rapidly and continuously inkjet-printed onto multiple substrates using a substrate tray that holds the substrate in place and moves relative to the inkjet printhead during inkjet printing, with or without controlled delay between consecutive printing steps. This allows for the simultaneous or rapid continuous inkjet printing of multiple device layers onto multiple substrates. Figure 7A and Figure 7B The diagram schematically illustrates a cross-sectional side view and a top view of a substrate tray 702 that holds multiple device substrates 704 arranged in an array. The device substrates 702 may be, for example, light guides, reflectors, diffusers, polarizers, anti-reflective material layers, or electrodes. The shape of the substrate is not limited to a rectangular shape. For example, wafers, as used in the semiconductor industry, may also be fabricated. The substrate tray 704 includes multiple fixing features that prevent the device substrates 704 from sliding across the surface of the substrate tray when the tray moves. The fixing features can take various forms. Figure 7A and 7B In the embodiment shown, the securing feature is a plurality of recessed regions 706 defined in the upper surface 708 of the substrate tray 704. The device substrate can be placed in each recessed region without the need for additional mechanisms to secure the substrate to the tray. Alternatively, the securing feature may include a locking mechanism that secures the substrate to the tray and / or provides precise positioning and alignment of the substrate in selected locations on the tray. For example, a spring-loaded pin may be placed between the device substrate 704 and the walls of its recessed regions 706 to prevent the substrate from moving within the recessed regions.

[0073] If alignment of the device substrate on the tray is critical and the tolerance of the fixed features is not high enough, an alignment sensor with sensing feedback can be used to precisely align the device substrate onto the substrate tray and then lock it in place on the tray by a locking mechanism. This sensor-assisted alignment can be performed after the substrate tray has been transferred to the inkjet printer but before inkjet printing the QD-containing layer, or before the substrate tray has been transferred to the inkjet printer.

[0074] In addition to QD, the QD-containing layer may also contain GSNP, PSNP, or a combination thereof. Alternatively, GSNP and / or PSNP may be contained in one or more individual layers of the CED. When GSNP and / or PSNP are introduced into the QD-containing layer, they improve the conversion performance of that layer. Furthermore, GSNP and PSNP provide enhanced light extraction by acting as light scattering centers in the matrix of the QD-containing layer and / or in individual layers of the CED. Incorporating GSNP and / or PSNP in combination with QD can increase the color conversion efficiency of the CED by increasing light scattering within the quantum dot layer, resulting in more interaction between photons and scattering particles, and thus the QD absorbs more light. Similar to QD, GSNP and PSNP can be introduced into the CED by including them in an ink composition and inkjet printing the ink composition to deposit them as layers, as described above regarding QD color filters.

[0075] The QD-containing layers and / or scattering nanoparticle-containing layers in a CED can be continuous or discontinuous, and can have a uniform or non-uniform distribution of QDs and / or scattering particles along their length and / or their thickness. Similarly, the QD-containing layers and / or scattering particle-containing layers in a CED can have a uniform or non-uniform thickness along their length. Non-uniform QD or scattering nanoparticle distributions or non-uniform layer thicknesses can be used, for example, to counteract non-uniform intensity distributions of QD-excited light in the layer. For example, using gradient concentrations of QDs and / or scattering nanoparticles in a given layer can provide more uniform light emission and / or colorimetry along the length of the CED by compensating for any non-uniformity in the intensity of light entering the QD-containing layer. Various embodiments of the CED will be illustrated in an LCD panel assembly in subsequent embodiments.

[0076] For simplicity, and except Figure 12In addition, in the accompanying drawings described below, scattering nanoparticles are represented by hollow circles, and quantum dots are represented by solid (filled) circles. Scattering nanoparticles represented by hollow circles may be GSNPs only, PSNPs only, or a mixture of GSNPs and PSNPs and are generally referred to as SNPs. Furthermore, some embodiments illustrated in the drawings include QD-containing layers that do not contain any SNPs. Although not depicted in all drawings, any QD-containing layer may also contain SNPs (GSNPs, PSNPs, or both) as a substitute for or complement to any single SNP-containing layer.

[0077] Figure 8 This is a top plan view of the CED 800, which uses inkjet printing to introduce QD material into sub-assemblies of the LCD device. (Compared to...) Figure 6 Similar to the combination of the light guide plate 660 and the QD-containing layer 670, the CED 800 can be used as a sub-assembly to achieve the same improvements. In this embodiment, the CED 800 has a non-uniform QD-containing layer consisting of a patterned array of QD-containing structures 822 deposited in constrained regions on the light guide plate 810. The QD-containing structures 822 are locally deposited on the first surface 811 using inkjet printing. The local density of these structures is controlled by the inkjet printing pattern. The number of QDs in each QD-containing structure can be controlled by the QD concentration in the ink composition, by the inkjet droplet volume, and / or by the number of inkjet droplets in each QD-containing structure. The local wetting properties on the surface can be “fine-tuned” using a surface treatment of the first surface 811 prior to the printing process, and the size and shape of the printed QD-containing structures can thus be controlled. The surface treatment can be performed in a patterned manner to improve printing resolution and structural profile. The light guide plate 810 is illuminated by LEDs 812 located at the proximal edge 815. In this side-light configuration, the light intensity in the light guide plate 810 decreases along its length. As a result, light coupled out from the light guide plate 810 enters a QD-containing structure 822 with a non-uniform light intensity distribution, wherein the intensity of light coupled out to the QD-containing structure closer to the near-end edge 815 is greater than the intensity of light coupled out to the QD-containing structure closer to the far-end edge 816. For this reason, the local density of the QD-containing structure 822 has a gradient along the length of the light guide plate 810, with a lower density at the near-end edge 815 and a higher density at the opposite edges of the light guide plate 810. This arrangement of the QD-containing structures compensates for the decrease in light intensity along the length of the light guide plate 810, thereby producing a more uniform emission along the length of the CED. Although Figure 8An ordered array of QD-containing structures 822 with a density gradient distribution is depicted. However, for various embodiments of the CED utilizing the QD-containing structures of this teaching, constrained regions with any pattern of any shape and aspect ratio can be formed on the first surface 811 of the light guide plate 810. Moreover, the size and fill density of the QD-containing structures can be determined by forming a defined pattern of the ink constrained regions. In various embodiments of the array of QD-containing structures, the array is formed to provide a microlens array.

[0078] Figure 9 This is a schematic cross-sectional view of the CED 800. Figure 8 and Figure 9 In the device, LED 812 can be a blue emitting LED having an emission line of, for example, but not limited to, 445 nm. The QD-containing structures 822 in this CED embodiment are dome-shaped, but they can have any arbitrary shape. Each structure contains multiple QDs, where the smaller QD designated as QD 830 is a green emitting QD, and the larger QD designated as QD 840 is a red emitting QD. The CED optionally includes a reflector 880 adjacent to the second surface 813 of the light guide plate 810. The reflector 880 can be attached to the light guide plate 810 using an optically clear adhesive (OCA); ideally, its refractive index is the same as or nearly the same as that of the light guide plate.

[0079] like Figure 9 As depicted, CED 800 may include a protective layer 826 deposited over an array of QD-containing structures 822. The protective layer 826 may be a thick layer encapsulating the QD-containing layers. For example, the thickness of the protective layer 826 may be between about 1 μm and about 100 μm. The protective layer 826 may be a thick polymer layer, such as polyethylene terephthalate (PET) or an acrylate-based polymer film. It should be noted that when the protective layer is a polymer layer, inkjet printing can be used for deposition, as illustrated in the example shown in U.S. Patent Publication 2016 / 0024322.

[0080] Figure 10 An alternative embodiment of a CED with an LED 812 illuminating its proximal edge 815 is shown. As indicated by the use of similar figures, the components of this CED can be compared with... Figure 9The components shown are identical, but in this embodiment, a discontinuous QD-containing layer, consisting of a QD-containing structure 822 and a protective layer 826, is printed onto the second surface 813 of the light guide plate 810. This allows light emitted through the second surface 813 to pass through the QD-containing structure 822 and the protective layer 826, be reflected from the reflector 880, and return through the QD-containing structure 822, the protective layer 826, and the light guide plate 810, before exiting the CED through the first surface 811. A similar geometry can be achieved by printing the QD-containing structure 822 and the protective layer 826B directly onto the surface of the reflector 880 facing the light guide plate 810, rather than onto the second surface 813 of the light guide plate 810. After the protective layer has been printed on the reflector, the reflector can be laminated onto the second surface of the light guide plate.

[0081] exist Figure 8 , 9 In the variant of the CED shown in 10, the QD-containing structures can be evenly spaced along the length of the light guide plate, but the concentration of QD in the QD-containing structures can be "fine-tuned" so that the concentration of QD in the QD-containing structures increases with the distance from the near edge of the light guide plate.

[0082] Figure 11 The diagram illustrates that the coupling output function and color conversion function can be separated in a CED on an adjacent layer. In this embodiment, the SNP 870 is distributed in a discontinuous layer consisting of multiple SNP-containing structures 823. These structures provide the device's coupling output function. Figure 9 Similar to the QD-containing structure 822, the SNP-containing structure 823 is dome-shaped, but it can have any arbitrary shape and is distributed with a density gradient along the length of the light guide plate 810. In this embodiment, QDs 830 / 840 are dispersed in the matrix of a continuous QD-containing layer 836, providing the color conversion function of the device. In this embodiment and in other embodiments, the SNP concentration gradient of the CED serves to improve the uniformity of light intensity coupled from the light guide plate 810 to the QD-containing layer 836, and ultimately also improves the uniformity of light intensity leaving the CED.

[0083] exist Figure 11 In the CED variant shown, the SNP-containing structures can be evenly spaced along the length of the light guide plate, but the concentration of SNPs in the SNP-containing structures can be "fine-tuned" so that the concentration of SNPs in the SNP-containing structures increases with the distance from the near edge of the light guide plate.

[0084] For simplicity, in this and other embodiments, a continuous layer 836 containing QDs is depicted as containing QDs of the same size. However, it should be understood that the layer containing QDs in the CED may contain different types of QDs, including green emitting QDs, red emitting QDs, blue emitting QDs, and combinations of two or more of them.

[0085] supply Figure 12 This is to clearly depict an example of a CED that includes both GSNP and PSNP. Therefore, unlike in other figures discussed herein, GSNP and PSNP are represented by hollow circles of different sizes. In particular, Figure 12 Larger hollow circles are used to represent GSNPs, while smaller hollow circles are used to represent PSNPs. Figure 12 In the embodiment depicted, the QD-containing layer 836 contains PSNP 875 dispersed in its matrix, while GSNP 823 is contained in a separate discontinuous layer.

[0086] Figure 13 An embodiment of a CED is shown, wherein SNP 870 is dispersed in a continuous SNP-containing layer 824, while QDs are dispersed in a separate continuous QD-containing layer 837 covering the SNP-containing layer 824. In this embodiment of the CED in which the scattering nanoparticles and quantum dots are located in separate layers, the intensity of the light coupled out from the SNP-containing layer has a uniform intensity distribution, even when the light coupled out from the light guide does not have a uniform intensity distribution—such as when the light guide is illuminated by a light source at its end edge. Because the light coupled out from the SNP-containing layer has a uniform intensity along its length, the QD-containing layer does not need to have a QD concentration gradient.

[0087] exist Figure 13In the illustrated embodiment, a continuous SNP-containing layer 824 is directly printed onto the first surface 811 of the light guide plate 810, and a continuous QD-containing layer 837 is directly printed onto the continuous SNP-containing layer 824. In this configuration, light emitted through the first surface 811 passes through the SNP-containing layer 824 and is scattered from the SNPs 870, causing the light to be coupled out to the QD-containing layer 837. To compensate for the higher light intensity at the near-end edge 815 of the light guide 810, a density gradient of SNPs 870 exists along the length of the SNP-containing layer 824, whereby the SNP density increases with distance from the near-end edge 815. To further compensate for the non-uniform light intensity emitted from the light guide plate 810, the SNP-containing layer 824 also has a variable thickness along its length, whereby the thickness of the SNP-containing layer increases with distance from the near-end edge 815. An alternative geometry can be achieved by directly printing the SNP-containing layer 824 onto the second surface 813 of the light guide plate 810 and printing the QD-containing layer 837 onto the first surface 811 of the light guide plate 810, or by directly printing the SNP-containing layer 824 onto the surface of the reflector 880 facing the light guide plate 810 and printing the QD-containing layer 837 onto the first surface 811 of the light guide plate 810.

[0088] Figure 14 It shows Figure 13 A variant of the CED in which QD 830 / 840 and SNP 870 are combined in a single layer, referred to herein as layer 825 containing QD / SNP. Figure 13 Similar to the SNP-containing layer 824 in the CED, the QD / SNP-containing layer 825 has a density gradient of SNP 870 and variable thickness along its length. Furthermore, like... Figure 13 Similar to layer 837 containing QD in the CED, layer 825 containing QD / SNP has a uniform QD concentration along its length. However, due to the wedge-shaped profile of layer 825 containing QD / SNP, the surface density of QD 830 / 840 (i.e., per mm as observed through the top surface of the layer) is relatively low. 2 The QD density increases from the near edge 817 to the far edge 818. An alternative geometry can be achieved by directly printing the QD / SNP-containing layer 825 onto the second surface 813 of the light guide plate 810, or by directly printing the QD / SNP-containing layer 825 onto the surface of the reflector 880 facing the light guide plate 810. For example, this structure can be achieved by simultaneously printing with two different inks (the first ink containing QD and the second ink containing SNP). Alternatively, a layer can be printed using the first ink, and then a layer can be printed using the second ink, and these printed layers can then diffuse into each other to produce layer 825.

[0089] Figure 15 and 16They are shown respectively Figure 13 and 14 A variant of the CED, in which layer 824 contains SNPs (in) Figure 15 In the case of) and layer 825 containing QD / SNP (in) Figure 16 (in the case of) having a uniform thickness along its length.

[0090] although Figure 9-16 The concentration gradient of QD and / or SNP in the CED shows a linear or substantially linear increase in particle concentration from the proximal edge to the distal edge, but other particle concentration patterns can also be used to provide a non-uniform particle concentration across the entire or partial printed layer. For example, the particle concentration may increase exponentially across the entire layer, or it may exhibit regular or irregular periodic variations across the entire layer. As further examples, the concentration of QD and / or scattering nanoparticles may increase from the distal edge of the layer to the proximal edge; from the top to the bottom of the layer; from the bottom to the top of the layer; or from the outer periphery of the layer to the center.

[0091] Figure 17 , 18 19 and 20 respectively show Figure 9 , 11 Variations of CEDs 15 and 16, wherein the light guide plate 810 is backlit rather than sidelit. (Again, although the device substrate is illustrated as a light guide plate in these embodiments, other device substrates, including diffusers or polarizers, can be used.) In each of these CEDs, the LED 812 illuminates the light guide plate 810 through the second surface 813 rather than the near-end edge 815. In the backlit device, the intensity of the light emitted from the light guide plate 810 has no edge-to-edge gradient. Therefore, in Figure 17 and 18 In the CED, the structure 822 containing QD and the structure 823 containing SNP are evenly spaced along the first surface 811 of the light guide plate 810. Figure 19 and 20 In the middle layer, the SNP-containing layer 824 and the QD / SNP-containing layer 825 have a uniform density of SNPs 870 along their lengths. Although not shown here, other embodiments of the side-lit CED can also be reconfigured into a backlit CED, including... Figure 9 , 12 The implementation schemes and their alternative geometries depicted in 13 and 14.

[0092] Although Figure 17-20In a backlit CED, the intensity of light emitted from the surface 811 of the light guide plate 810 has no edge-to-edge gradient. However, due to the placement of the LEDs 812, the intensity of light emitted from the light guide plate 810 may be uneven. Higher intensity light enters the portion of the light guide plate directly above the LEDs, while lower intensity light enters the portion of the light guide plate between the LEDs. Figure 21 An embodiment of the CED that compensates for this intensity non-uniformity is shown. As illustrated in the figure, the thicknesses of the SNP-containing layer 824B and the QD-containing layer 837C can be modulated along their lengths.

[0093] By sequential or simultaneous inkjet printing of three or more different ink compositions, a particulate layer in a CED can be printed as a continuous layer with a QD concentration gradient, a GSNP concentration gradient, a PSNP concentration gradient, or a combination thereof. Although Figure 8-16 The layers are typically depicted as having linear or substantially linear QD and / or SNP concentration gradients along their length, but as discussed above, these layers may be printed with other gradient patterns, including exponential gradients.

[0094] One embodiment of an inkjet printing method for continuous layers having a QD concentration gradient and / or a SNP concentration gradient employs three inks. In some embodiments of these multi-ink printing methods, the first ink composition contains QD and a binder; the second ink composition contains SNP and a binder; and the third ink composition contains a binder but no QD or SNP. Using this method, the concentration of particles (QD or SNP) printed onto a given surface area will be determined by the concentrations of QD and SNP in their respective ink compositions and the volume ratio of the three ink compositions printed on that surface area. The volume of the ink composition can be controlled by controlling the number of ink composition drops printed per unit area (“DPA”). For example, the total number of drops per unit area (DPA) 粘结剂 +(DPA) SNP +(DPA) QD Under constant conditions, by satisfying the relation (DPA). 粘结剂 >(DPA) SNP >(DPA) QD The first portion of the layer formed by the volumetric printing of three ink compositions will be larger than that formed by satisfying the relationship (DPA). QD >(DPA) SNP >(DPA) 粘结剂 The volumetric concentration of the film formed by printing the three ink compositions is lower than that of the other part of the film.

[0095] These three ink compositions can be printed simultaneously, sequentially, or in combination on the surface of a substrate such as a light guide plate, transparent substrate, diffuser, or reflector. For example, two ink compositions can be printed simultaneously, and a third ink composition can be printed subsequently. If the different ink compositions are to form separate and distinct layers in the printed film, the ink compositions can be printed sequentially and allowed to dry or cure before printing subsequent layers. Alternatively, if the different ink compositions are to form a single blend layer in which the binder and particles in the ink compositions are mixed together, the ink compositions can be printed simultaneously or sequentially. When different ink compositions are printed sequentially and a blend layer is required, the printing should be performed according to a schedule that allows the ink compositions to blend into a single layer before the ink compositions dry or cure into a film.

[0096] Figure 22 The diagram schematically illustrates a method for inkjet printing a layer containing QDs on a substrate surface. This method will be described below as an inkjet printing method for a layer containing both QDs and SNPs on a substrate surface, wherein the layer has an SNP concentration gradient from one edge to the other. However, by changing the ink composition used and the deposition sequence of the ink composition, layers containing only QDs or only SNPs can also be printed using the same equipment and general procedures. Additionally, general references are made to... Figure 22 This describes ink compositions used for inkjet printing various layers. A more detailed description of ink compositions that can be used to form one or more layers in a CED is provided below.

[0097] like Figure 22As shown in Figure (a), the inkjet printing process can be initiated by printing a material layer 2201 onto the surface 2202 of a substrate 2203. As discussed earlier, the substrate can take the form of various device substrates, such as light guides, reflectors, or polarizers. In the embodiment depicted here, three inkjet nozzles 2204A, 2204B, and 2204C are used, each printing droplets of different ink compositions 2205A, 2205B, and 2205C. For example, ink composition 2205A may contain a curable polymer binder without any QD or SNP. This ink composition acts as a diluent for other ink compositions during the subsequent printing process of 2201. Ink composition 2205B may contain a curable binder and QD, and ink composition 2205C may contain a curable binder and SNP. To form printed layer 2201, droplets of ink compositions 2205A, 2205B, and 2205C are simultaneously or sequentially ejected from nozzles 2204A, 2204B, and 2204C onto surface 2202. As printing progresses from the first edge 2206 to the second edge 2207 of printed layer 2201, the relative volume ratio of the three ink compositions is adjusted to achieve the desired bulk density of QD and SNP. For example, the density of SNP is lowest at the first edge 2206 and higher at the second edge 2206, while the bulk density of QD remains constant from edge to edge. The polymer binder of the matrix forming the cured layer may be the same or different for each ink composition. If the ink compositions are to be printed continuously and then mixed to form a single layer, the polymer binder should be miscible. Once printed, the layer can be cured by, for example, UV curing, thermal curing, or a combination thereof. Although not shown here, if QD and SNP are inkjet printed as separate layers, the polymer binder may be the same. This could be advantageous for devices in which these layers ideally have the same refractive index.

[0098] Optional, such as Figure 22As shown in Figure (b), a second layer 2210 can be printed over the first printed layer 2201 using one or more inkjet nozzles 2204A, 2204B, and / or 2204C, and this layer can also be cured after deposition. Next, a QD- and SNP-free polymer protective layer 2211 can be inkjet printed over the second layer 2210 using an ink composition 2205D containing a protective curable polymer (Figure (c)). Once cured, the polymer protective layer 2211 will help protect the first layer 2201 and the second layer 2210 from the damaging effects of exposure to the atmosphere, such as water, oxygen, and / or ozone, and allow the CED to be operated before being incorporated into a larger device structure. Additionally, the printed polymer protective layer 2211 can protect layers 2201 and 2210 from the damaging effects of subsequent device processing steps such as plasma-enhanced chemical vapor deposition (PECVD). For example, as shown in Figure (d), PECVD can be used to deposit an inorganic barrier layer 2212 over the polymer protective layer 2211. The inorganic barrier layer will provide an enhanced degree of atmospheric protection. In various embodiments, the barrier layer 2212 can be a deposited dense layer of inorganic material, such as those selected from inorganic material categories, including metal oxides, metal nitrides, metal carbides, metal oxynitrides, metal boron oxides, and combinations thereof. For the inorganic barrier layer 2212, for example, but not limited to, SiN can be used. x Al2O3, TiO2, HfO2, SiO x N y Or a combination thereof. Alternatively, as shown in Figure (e), a polymer film 2213 may be directly laminated onto the polymer protective layer 2211. (The polymer film 2213 may also be directly laminated onto the inorganic barrier layer 2212 in Figure (d).) The laminated polymer film 2213 can provide an additional level of protection and may be permanently laminated to the structure so that it can eventually be incorporated into the final device structure, or it may be temporarily attached so that it can be removed prior to final device assembly. Figure 22 Image (f) illustrates the temporary attachment of the laminated polymer film 2213 to the underlying structure, wherein a coating 2214 of an optically transparent adhesive is provided between the printed polymer protective layer 2211 and the laminated polymer film 2213.

[0099] Although the article discusses and Figure 22The method for printing a film layer with a particle concentration gradient shown uses at least three ink compositions, but more than three ink compositions or fewer ink compositions may also be used. For example, the printing method may use two or more different QD-containing ink compositions with different quantum dot concentrations or types, or two or more different ink compositions containing scattering nanoparticles with different scattering nanoparticle concentrations or types. For example, in some embodiments of the printing method, an ink composition containing PSNP and a binder may be used together with a separate ink composition containing GSNP and a binder. Alternatively, only two ink compositions may be used. For example, if a layer containing only one type of particle (e.g., QD only, GSNP only, or PSNP only) is being printed, the first ink composition may contain the particles and the binder, and the second ink composition may contain the binder but not the particles. By printing two ink compositions simultaneously or sequentially and varying the number of drops per unit area of ​​the two ink compositions during printing, as discussed above regarding the three-ink-composition scheme, a layer with a particle gradient along its length can be achieved. Alternatively, this concept also supports cases with more than three inks. For example, for SNPs and adhesives, several inks in which the SNPs are PSNPs of different particle sizes can be used.

[0100] For some applications, it may be advantageous to provide a sealing layer around the perimeter of the CED or around at least one or more layers of the CED. These sealing layers can be abutted against another device layer to provide a waterproof and / or oxygen-proof edge seal. CEDs made with sealing layers can be cut to size and sealed into devices without the risk of lateral water and / or oxygen ingress and subsequent damage to the CED. Figure 23 and 24 A schematic diagram of a method for forming a CED with a sealing layer is shown. In this embodiment, the sealing layer comprises a plurality of sealing dikes 2302, which are inkjet printed onto a substrate 2304 using an ink composition 2306 comprising a curable sealing material such as a curable monomer, oligomer, polymer, or mixture thereof, and optionally a SNP. Figure 23 (Left image). In some embodiments of the sealing layer, the sealing dam 2302 has SNPs dispersed therein. In these embodiments, the SNPs can be used to help redirect light from a light source, such as a backlight unit, into a QD-containing layer printed between the sealing dams (described below). Similar to the QD-containing layer and SNP-containing layer of the CED described above, the SNPs within or between different sealing dams can have a non-uniform (e.g., gradient) density distribution on the sealing layer to provide a CED with more uniform light emission. Although Figure 23 The sealing dam 2302 is described as being inkjet printed, but other manufacturing methods such as nanoimprinting can be used to form these dams.

[0101] Optionally, a barrier layer 2308 is formed over the exposed portions of the sealing barrier 2302 and the substrate 2304. Figure 23 (See the image on the right). This barrier layer can be, for example, an inorganic material such as SiN. x Al2O3, TiO2, HfO2, SiO x N y Or a combination of them, will provide additional protection against water and / or oxygen.

[0102] Once the barrier layer is formed, one or more layers of CED 2310, including layers containing QD and / or layers containing SNP, can be inkjet printed into the recesses 2312 defined between the sealing dams 2302. Figure 24 As shown in the left image. A temporary or permanent membrane 2314 can then be sealed to the sealing dike 2302 to cover and protect the CED layer 1910. Figure 24 (Image on the right).

[0103] It should be noted that although the formation of various device layers is described herein as including a curing step, device layers formed from non-curable compositions can be simply formed by drying.

[0104] Ink Composition

[0105] The following teachings relate to various embodiments of ink compositions that, once printed and dried and / or cured, form a thin polymer layer, including but not limited to local filter layers, global filter layers, light emitting layers, light scattering layers, and / or color enhancement layers as described herein. Various embodiments of the ink compositions can be printed using, for example, an industrial inkjet printing system enclosed in a gas hood that defines an interior with a controlled environment maintained as inert and substantially low-particle process environment. A QD-containing light emitting layer can be inkjet printed over various previously formed device substrates such as light polarizers or local filter layers of the types disclosed herein, and then cured using, for example, thermal or ultraviolet (UV) curing.

[0106] A wide variety of ink compositions are expected to be printable in an inert, substantially low-particle environment in various embodiments of the gas hood system. For example, in the manufacturing process of LCD devices, LCD sub-pixels can be formed to include the various device layers described herein. Various ink compositions for sub-pixels can be inkjet printed using ink compositions that are "fine-tuned" for forming layers containing absorbent dyes, QD-containing layers for red, green, or blue sub-pixels, layers containing scattering nanoparticles, or QD-free polymer matrix layers and polymer planarization layers for blue sub-pixels.

[0107] Some embodiments of the ink composition include polymeric components, such as, but not limited to, various acrylate monomers, such as monodentate or multidentate acrylates; various methacrylate monomers, such as monodentate or multidentate methacrylates; and copolymers and mixtures thereof. The polymeric components can be cured using heat treatment (e.g., baking), UV exposure, and combinations thereof. As used herein, polymers and copolymers can include any form of polymeric component that can be formulated into an ink and cured on a substrate to form an organic layer. Such polymeric components can include polymers and copolymers, as well as their precursors, such as, but not limited to, monomers, oligomers, and resins. Some embodiments of the ink composition also include light absorbers, QD, GSNP, PSNP, and combinations thereof dispersed in the polymeric component.

[0108] In addition to a multifunctional crosslinking agent, the ink composition also comprises one or more mono(meth)acrylate monomers, one or more di(meth)acrylate monomers, or a combination of mono(meth)acrylate and di(meth)acrylate monomers. As used herein, the phrase "(meth)acrylate monomer" means that the monomer can be an acrylate or a methacrylate. Some embodiments of the ink composition also include a crosslinking photoinitiator. Such jettable ink compositions (with or without QD, scattering particles, and / or light-absorbing pigments and / or organic dyes) that can be used to print one or more polymer films are described in U.S. Patent Application Publication No. 2016 / 0024322, filed July 22, 2015, and U.S. Patent Application Publication No. 2017 / 0062762, filed July 19, 2016, the entire contents of which are incorporated herein by reference.

[0109] Mono(meth)acrylate and di(meth)acrylate monomers are ethers and / or esters with film-forming and spreading properties, which make them suitable for inkjet printing applications. As components of ink compositions, these monomers provide a jettable composition at a range of inkjet printing temperatures, including room temperature. Typically, for ink compositions suitable for inkjet printing applications, the surface tension, viscosity, and wettability of the ink composition should be fine-tuned to allow the composition to be dispensed through the inkjet printing nozzle without drying or clogging the nozzle at the printing temperatures (e.g., room temperature to 22°C, or higher, e.g., up to about 40°C). Once formulated, various embodiments of the ink composition may have a viscosity at 22°C, for example, between about 2 cp and about 30 cp (including, for example, between about 10 cp and about 27 cp and about 14 cp and about 25 cp), and a surface tension at 22°C between about 25 dynes / cm and about 45 dynes / cm (including, for example, between about 30 dynes / cm and about 42 dynes / cm and about 28 dynes / cm and about 38 dynes / cm).

[0110] The appropriate viscosity and surface tension of each monomer used in an ink composition depend on the viscosity and surface tension of the other components present in a given ink composition, as well as the relative amount of each component in the ink composition. However, typically, the viscosity of mono(meth)acrylate monomers and di(meth)acrylate monomers at 22°C is in the range of about 4 cp to about 22 cp, including about 4 cp to about 18 cp at 22°C, and the surface tension at 22°C is in the range of about 30 dynes / cm to 41 dynes / cm, including about 32 dynes / cm to 41 dynes / cm at 22°C. Methods for measuring viscosity and surface tension are well known, including the use of commercially available rheometers (e.g., DV-I Prime Brookfield rheometer) and tensiometers (e.g., SITA bubble pressure tensiometer).

[0111] In some embodiments of the ink composition, including those with high QD and / or scattering nanoparticle loading, an organic solvent may be added to adjust the viscosity and / or surface tension of the ink composition if the viscosity and / or surface tension fall outside these ranges in the absence of an organic solvent. Suitable organic solvents include esters and ethers. Examples of organic solvents that may be included in the ink composition include high-boiling-point organic solvents, including organic solvents with a boiling point of at least 200°C. This includes organic solvents with a boiling point of at least 230°C, at least 250°C, or even at least 280°C. Examples of high-boiling-point organic solvents that may be used are diols and glycols, such as propylene glycol, pentanediol, diethylene glycol, and triethylene glycol. High-boiling-point aprotic solvents may also be used, including aprotic solvents with a boiling point of at least 240°C. Examples of higher-boiling-point aprotic solvents include sulfolane: 2,3,4,5-tetrahydrothiophene-1,1-dioxide (also known as tetramethylene sulfone). Other non-limiting exemplary organic solvents may include toluene, xylene, mesitylene, propylene glycol methyl ether, methylnaphthalene, methyl benzoate, tetrahydronaphthalene, dimethylformamide, terpineol, phenoxyethanol, and butyrophenone.

[0112] The mono(meth)acrylate monomers and di(meth)acrylate monomers may be, for example, linear aliphatic mono(meth)acrylates and di(meth)acrylates, or may include cyclic and / or aromatic groups. In various embodiments of the inkjet-printable ink composition, the mono(meth)acrylate monomers and / or di(meth)acrylate monomers are polyethers. In various embodiments of the inkjet-printable ink composition, the di(meth)acrylate monomers are alkoxylated aliphatic di(meth)acrylate monomers. These include di(meth)acrylates containing neopentyl glycol groups, including alkoxylated neopentyl glycol diacrylates, such as neopentyl glycol propoxylated di(meth)acrylate and neopentyl glycol ethoxylated di(meth)acrylate. The molecular weights of the various embodiments of the di(meth)acrylates containing neopentyl glycol groups are in the range of about 200 g / mol to about 400 g / mol. This includes neopentyl glycol-containing di(meth)acrylates with molecular weights ranging from about 280 g / mol to about 350 g / mol, and also includes neopentyl glycol-containing di(meth)acrylates with molecular weights ranging from about 300 g / mol to about 330 g / mol. Various neopentyl glycol-containing di(meth)acrylate monomers are commercially available. For example, neopentyl glycol propoxylated diacrylate is available under the trade name SR9003B from Sartomer Corporation, or under the trade name Aldrich-412147 from Sigma Aldrich Corporation (~330 g / mol; viscosity at 24°C ~18 cp; surface tension at 24°C ~34 dynes / cm). Neopentyl glycol diacrylate is also available under the trade name Aldrich-408255 from Sigma Aldrich Corporation (~212 g / mol; viscosity ~7 cp; surface tension ~33 dynes / cm).

[0113] Other suitable (meth)acrylate monomers include, but are not limited to: alkyl (meth)acrylates, such as methyl (meth)acrylate and ethyl (meth)acrylate; cyclic trimethylolpropane acetal (meth)acrylate; alkoxylated tetrahydrofurfuryl (meth)acrylate; phenoxyalkyl (meth)acrylates, such as 2-phenoxyethyl (meth)acrylate and phenoxymethyl (meth)acrylate; and 2-(2-ethoxyethoxy)ethyl (meth)acrylate. Other suitable di(meth)acrylate monomers include 1,6-hexanediol diacrylate, 1,12-dodecanediol di(meth)acrylate; 1,3-butanediol di(meth)acrylate; di(ethylene glycol) methyl ether methacrylate; and polyethylene glycol di(meth)acrylate monomers, including ethylene glycol di(meth)acrylate monomers and polyethylene glycol di(meth)acrylate monomers with a number average molecular weight in the range of, for example, from about 230 g / mol to about 440 g / mol. For example, the ink composition may comprise polyethylene glycol 200 dimethacrylate and / or polyethylene glycol 200 diacrylate with a number average molecular weight of about 330 g / mol. Other mono- and di(meth)acrylate monomers that may be included alone or in combination in various embodiments of the ink composition include dicyclopentenoxyethyl acrylate (DCPOEA), isobornyl acrylate (ISOBA), dicyclopentenoxyethyl methacrylate (DCPOEMA), isobornyl methacrylate (ISOBMA), and N-octadecyl methacrylate (OctaM). ISOBA and ISOBMA homologues (collectively, “ISOB(M)A” homologues) in which one or more methyl groups on the ring are replaced by hydrogen may also be used.

[0114] Multifunctional (meth)acrylate crosslinking agents ideally have at least three reactive (meth)acrylate groups. Therefore, multifunctional (meth)acrylate crosslinking agents can be, for example, tri(meth)acrylate, tetra(meth)acrylate, and / or more functional (meth)acrylates. Pentaerythritol tetraacrylate or pentaerythritol tetramethacrylate, di(trimethylolpropane)tetraacrylate, and di(trimethylolpropane)tetramethacrylate are examples of multifunctional (meth)acrylates that can be used as primary crosslinking agents. The term "primary" is used herein to indicate that other components of the ink composition may also participate in crosslinking, but this is not their primary functional purpose.

[0115] The ink composition may optionally contain a photoinitiator to initiate the polymerization process. Ink compositions suitable for inkjet printing of local and global filter layers may also contain light-absorbing dyes and / or pigments dispersed in the polymer component.

[0116] Ink compositions suitable for inkjet printing of QD-containing layers and scattering particle-containing layers further comprise QDs and / or scattering particles dispersed in the polymer component. Scattering particles may be, for example, GSNPs and / or PSNPs. The ink composition may contain more than one type of particle. For example, various embodiments of the ink composition contain a mixture of QDs and PSNPs; a mixture of QDs and GSNPs; or a mixture of QDs, GSNPs, and PSNPs. QD-containing ink compositions may contain more than one type of QD; for example, an ink composition for a QD-containing layer to be irradiated with blue light may contain a mixture of red-emitting QDs and green-emitting QDs; an ink composition for a QD-containing layer to be irradiated with ultraviolet light may contain a mixture of blue-emitting QDs, red-emitting QDs, and green-emitting QDs; an ink composition for a light-emitting layer for red pixels may contain only red-emitting QDs; an ink composition for a light-emitting layer for green pixels may contain only green-emitting QDs; and an ink composition for a light-emitting layer for blue pixels may optionally contain only blue-emitting QDs.

[0117] Ink compositions containing GSNPs may contain more than one type of GSNP, wherein different types of GSNPs may have different nominal particle size and / or shape, particulate material, or both. Similarly, ink compositions containing PSNPs may contain more than one type of PSNP, wherein different types of PSNPs may have different nominal particle size and / or shape, particulate material, or both.

[0118] QDs optionally include a surface film of end-capped ligands. These end-capped ligands, which help passivate QDs and stabilize them to prevent aggregation, are often present due to the solution-phase growth of QDs. Additionally, ink compositions containing QDs may also contain a second type of ligand, referred to herein as crosslinkable ligands. Crosslinkable ligands are typically linked to QDs via hydrogen bonding and covalently crosslink with polymer components in the ink composition as they cure. Crosslinkable ligands are monomers characterized by having one or more functional groups with polymerizable double bonds, such as acrylate or methacrylate groups, and functional groups that will specifically connect with the surface of QDs in the ink composition. The monomers may also contain spacer chains separating these functional groups. This bifunctionality of crosslinkable ligands keeps QDs dispersed in the curable ink composition and prevents them from re-aggregating during curing. For example, monomers containing carboxyl (-COOH), amine (-NR2, where R is a H atom or alkyl group), and thiol (-SH) groups have a strong binding affinity for QDs composed of group II-VI elements. 2-Carboxyethyl acrylate (2CEA) is an example of a crosslinkable ligand used in conjunction with octadecylamine-terminated core-shell CdSe / ZnS QD.

[0119] In some embodiments of the ink compositions, mono(meth)acrylate and / or di(meth)acrylate monomers are the major components of the ink composition on a weight basis. Various embodiments of these ink compositions have a combined content of mono(meth)acrylate and di(meth)acrylate monomers ranging from about 65% to about 96% by weight. (That is, the combined weight of all mono(meth)acrylate and di(meth)acrylate monomers in the ink composition accounts for about 65% to about 96% by weight of the ink composition; however, the ink composition does not need to contain both mono(meth)acrylate and di(meth)acrylate monomers simultaneously.) This includes embodiments of ink compositions where the combined content of mono(meth)acrylate and di(meth)acrylate monomers ranges from about 65% to about 96% by weight or from about 75% to 95% by weight, and also includes embodiments of ink compositions where the combined content of mono(meth)acrylate and di(meth)acrylate monomers ranges from about 80% to 90% by weight. Some embodiments of the ink composition contain only a single mono(meth)acrylate monomer or a single di(meth)acrylate monomer, while other embodiments contain a mixture of two or more mono(meth)acrylate monomers and / or di(meth)acrylate monomers. For example, various embodiments of the ink composition contain two mono(meth)acrylate monomers, two di(meth)acrylate monomers, or a combination of a mono(meth)acrylate monomer and a di(meth)acrylate monomer. The weight ratio of the two monomers can be significantly varied to “fine-tune” the viscosity, surface tension, and film-forming properties of the ink composition. For example, some embodiments of ink compositions containing two of the mono(meth)acrylate or di(meth)acrylate monomers contain a first mono(meth)acrylate or di(meth)acrylate monomer and a second mono(meth)acrylate or di(meth)acrylate monomer in a weight ratio ranging from 95:1 to 1:2, including a weight ratio ranging from 12:5 to 1:2. This includes embodiments of ink compositions in which the weight ratio of the first mono(meth)acrylate or di(meth)acrylate monomer to the second mono(meth)acrylate or di(meth)acrylate monomer is in the range of 12:5 to 4:5; embodiments of ink compositions in which the weight ratio of the first mono(meth)acrylate or di(meth)acrylate monomer to the second mono(meth)acrylate or di(meth)acrylate monomer is in the range of 5:4 to 1:2; and embodiments of ink compositions in which the weight ratio of the first mono(meth)acrylate or di(meth)acrylate monomer to the second mono(meth)acrylate or di(meth)acrylate monomer is in the range of 5:1 to 5:4. For the purposes of the weight percentages and weight ratios described in this paragraph, any crosslinking ligands present in the ink composition are not considered mono(meth)acrylate or di(meth)acrylate monomers.

[0120] Ink compositions containing QD typically have a QD concentration ranging from about 0.1 wt% to about 5 wt%, including a QD concentration ranging from about 0.5 wt% to about 2 wt% – but concentrations outside these ranges are also possible. The concentration of PSNP can be very low because even small amounts of PSNP can cause significant differences in the emission properties of the QD-containing layer. Therefore, in ink compositions containing both QD and PSNP, the PSNP concentration is typically significantly lower than the QD concentration. For example, various embodiments of the ink composition have a PSNP concentration ranging from about 0.01 wt% to about 5 wt%, including PSNP concentrations ranging from about 0.01 wt% to about 1 wt% and from about 0.02 wt% to about 0.1 wt%. For example, various embodiments of the ink composition have a GSNP concentration ranging from about 0.01 wt% to 12 wt%, including GSNP concentrations ranging from about 1 wt% to about 10 wt%.

[0121] If the ink composition containing QD contains one or more crosslinkable ligands, they typically comprise about 1% to about 10% by weight of the ink composition, including about 2% to about 8% by weight of the ink composition.

[0122] Embodiments of ink compositions for printing color filters containing QD layers may have a higher QD loading than those discussed above. For example, various embodiments of QD-containing ink compositions for color filters may have a QD concentration ranging from about 5% to about 50% by weight, including a QD concentration ranging from about 10% to about 35% by weight. Therefore, the content of mono(meth)acrylate and di(meth)acrylate monomers in these ink compositions will be lower than the contents discussed above. For example, various embodiments of QD-containing ink compositions for color filters may have a mono(meth)acrylate and di(meth)acrylate monomer content ranging from about 50% to about 90% by weight. This includes embodiments of ink compositions with a mono(meth)acrylate and di(meth)acrylate monomer content ranging from about 60% to about 80% by weight, and also includes embodiments of ink compositions with a mono(meth)acrylate and di(meth)acrylate monomer content ranging from about 65% to 75% by weight. As discussed above, organic solvents can be added to these ink compositions to give them a viscosity and / or surface tension suitable for inkjet printing. Suitable organic solvents include esters and ethers. Examples of organic solvents that may be included in ink compositions include high-boiling-point organic solvents, including those with a boiling point of at least 200°C. This includes organic solvents with boiling points of at least 230°C, at least 250°C, or even at least 280°C. Examples of high-boiling-point organic solvents that may be used are diols and glycols, such as propylene glycol, pentanediol, diethylene glycol, and triethylene glycol. High-boiling-point aprotic solvents may also be used, including those with a boiling point of at least 240°C. Examples of higher-boiling-point aprotic solvents include sulfolane: 2,3,4,5-tetrahydrothiophene-1,1-dioxide (also known as tetramethylene sulfone). Other non-limiting exemplary organic solvents may include xylene, mesitylene, propylene glycol methyl ether, methylnaphthalene, methyl benzoate, tetrahydronaphthalene, dimethylformamide, terpineol, phenoxyethanol, and butyrophenone. If the ink composition contains an organic solvent, the above QD and monomer concentrations are based on the solids content of the ink composition.

[0123] For various embodiments of the organic thin-film ink composition, the multifunctional (meth)acrylate crosslinking agent may account for about 4% to about 10% by weight of the ink composition. Typically, the photoinitiator is included in an amount ranging from about 0.1% to about 10% by weight, including amounts ranging from about 0.1% to about 8% by weight. This includes embodiments in which the photoinitiator is present in an amount ranging from about 1% to about 6% by weight, embodiments in which the photoinitiator is present in an amount ranging from about 3% to about 6% by weight, and embodiments in which the photoinitiator is present in an amount ranging from about 3.75% to about 4.25% by weight.

[0124] The specific photoinitiators used for a given ink composition are ideally selected such that they are activated at wavelengths that do not impair the materials used in the manufacture of the device, such as those used in the manufacture of LCD display devices. The photoinitiators can be selected such that initial polymerization is induced at wavelengths in the UV region of the electromagnetic spectrum, the blue region of the visible spectrum, or both. For example, a QD-containing ink composition containing a mixture of green-emitting QDs and red-emitting QDs can be used to print a QD-containing layer that can be irradiated with blue incident light. A portion of the blue light is then converted into red and green light to produce white light. The ink composition may contain a photoinitiator that will trigger polymerization at wavelengths in the blue region of the electromagnetic spectrum. Although the blue light will be slightly attenuated by the QDs in the layer, it will still penetrate the film. Therefore, a fully cured layer can be achieved using a light source that emits blue light. For example, an LED with a peak intensity at approximately 395 nm can be used. The photoinitiator eventually decomposes (bleaches) during the curing process, so the blue absorption of the photoinitiator gradually decreases until it becomes colorless. Therefore, the emission spectrum of the layer will change during curing, but the final white light emission spectrum can be controlled by taking into account the role of the photoinitiator.

[0125] Acylphosphine oxide photoinitiators can be used, but it should be understood that a wide range of photoinitiators can be used. Photoinitiators such as, but not limited to, those selected from α-hydroxy ketones, phenyl glyoxylates, and α-amino ketones are also considered. Various types of photoinitiators can have absorption profiles between about 200 nm and about 400 nm to initiate free radical-based polymerization. For the various embodiments of the ink compositions and printing methods disclosed herein, 2,4,6-trimethylbenzoyl-diphenylphosphine oxide (TPO) and 2,4,6-trimethylbenzoyl-diphenylphosphine esters possess the desired properties. Examples of acylphosphine photoinitiators include those marketed under trade names... TPO is sold for UV curing. TPO (formerly also known as a product name) TPO was obtained as an initiator, a type I hemolytic initiator with an absorption wavelength of 380 nm; TPO-L, a type I photoinitiator, absorbs at a wavelength of 380 nm; and 819, absorption wavelength 370nm. For example, it can be used at up to 1.5J / cm 2 The ink composition containing TPO photoinitiator is cured by a light source emitting radiation energy density at a nominal wavelength in the range of 350 nm to 395 nm. With appropriate energy, high levels of curing can be achieved. For example, some embodiments of the cured film have a degree of curing of over 90%, as measured by Fourier transform infrared (FTIR) spectroscopy.

[0126] Considering the potential for photo-induced polymerization, ink compositions can be prepared under conditions that prevent exposure to light. Regarding the preparation of the organic thin-film ink compositions of this teaching, to ensure the stability of various compositions, they can be prepared in darkness or in a dimly lit room, or in a facility where lighting is controlled to exclude wavelengths that would induce polymerization. Such wavelengths typically include those below about 500 nm.

[0127] Figure 26 A flowchart of a method for formulating an ink composition containing QD is provided. To formulate the ink composition, a mixture 2601 of mono(meth)acrylate and / or di(meth)acrylate monomers and a polyfunctional (meth)acrylate crosslinking agent is mixed with a photoinitiator 2603 to form an initial curable monomer blend 2605. If the ink composition is to contain crosslinkable ligands 2604, they may also be added to the curable monomer blend 2605. QD 2606 and optionally GSNP 2607 and / or PSNP 2608 are then dispersed in the curable monomer blend 2605 to form a dispersion 2609. QD and other particles may be added in the form of a dispersion based on an aqueous or non-aqueous organic solvent. If so, water or organic solvent may optionally be removed from the dispersion 2609 to form a second dispersion 2610. The ink composition is then ready for use and should be stored protected from light. Once the ink composition is prepared, it can be dehydrated by mixing it in the presence of molecular sieve beads for a day or longer and then stored in a dry, inert atmosphere such as compressed dry air.

[0128] The ink composition can be printed using a printing system such as that described in US 8,714,719, the entire contents of which are incorporated herein by reference. The film can be cured using UV radiation in an inert nitrogen atmosphere. The ink composition is designed for application by inkjet printing and is therefore characterized by jettability, wherein the jettability ink composition exhibits a constant or substantially constant drop rate, drop volume, and drop trajectory over time when continuously jetted through the nozzles of the printhead. Additionally, the ink composition ideally features good latency, where latency refers to the time the nozzle can remain exposed and idle before a significant deterioration in performance (e.g., a decrease in drop rate or drop volume and / or a change in trajectory, which would significantly affect image quality).

[0129] For illustrative purposes only, various embodiments of a QD-containing ink composition for printing QD-containing layers for photonic devices are immediately described in the following and subsequent examples. One embodiment of the ink composition comprises 75-95% by weight of polyethylene glycol dimethacrylate monomer, polyethylene glycol diacrylate monomer, or a combination thereof, wherein the number average molecular weight of the polyethylene glycol dimethacrylate monomer and the polyethylene glycol diacrylate monomer is in the range of about 230 g / mol to about 430 g / mol; 1% to 10% by weight of a multifunctional (meth)acrylate crosslinking agent; and 0.1% to 5% by weight of quantum dots.

[0130] Another embodiment of the ink composition comprises 70% to 95% by weight of a neopentyl glycol-containing diacrylate monomer, a neopentyl glycol-containing dimethacrylate monomer, or a combination thereof; 1% to 10% by weight of a multifunctional (meth)acrylate crosslinking agent; and 0.1% to 5% by weight of quantum dots.

[0131] Various embodiments of the ink compositions of the present invention can be printed and deposited on substrates such as glass, silicon and / or silicon nitride using patterned regions of continuous or discontinuous layers.

[0132] Example Ink Composition

[0133] Example 1 This embodiment illustrates the formulation of various curable ink compositions that can be used to inkjet print various layers of QD color filters or CEDs, including ink compositions containing QD.

[0134] Seven illustrative inkjet-printable ink compositions were prepared. Each ink composition contains a single mono- or diacrylate monomer as the main polymer component. The seven monomers are cyclic trimethylolpropane acetal acrylate, propoxylated neopentyl glycol diacrylate, alkoxylated tetrahydrofurfuryl acrylate, 2-phenoxyethyl acrylate, 1,6-hexanediol diacrylate, 1,3-butanediol diacrylate, and 2-(2-ethoxyethoxy)ethyl acrylate. The structure, room temperature (~22°C) surface tension, and room temperature viscosity of each monomer are described in detail. Figure 25 The table presents the results. Each ink composition contains 89% by weight of mono- or diacrylate monomers; 7% by weight of pentaerythritol tetraacrylate (PET) as a multifunctional acrylate crosslinking agent; and 4% by weight of photoinitiator 2,4,6-trimethylbenzoyl-diphenylphosphine oxide (TPO). The ink compositions were formulated by mixing the three components overnight and filtering the mixture through a 0.45 μm PTFE membrane filter. The inkjet performance and low-temperature silicon nitride (SiN) treatment under UV ozone (UVO) were then tested using a Dimatix printer. xFilm formation on the substrate. All ink compositions exhibit good jetting behavior and are capable of forming films with a thickness of 2 μm or higher.

[0135] Layers printed using inks containing monomers such as propoxylated neopentyl glycol diacrylate, alkoxylated tetrahydrofurfuryl acrylate, and 1,6-hexanediol diacrylate exhibit the most controllable film formation and optimal edge definition. Therefore, ink compositions containing propoxylated neopentyl glycol diacrylate and ink compositions containing 1,6-hexanediol diacrylate were selected to illustrate the formulation of QD-containing ink compositions. 5% by weight of 2-carboxyethyl acrylate (2CEA) was added to each ink composition as a crosslinkable ligand to prepare for the subsequent addition of octadecylamine-terminated core-shell CdSe / ZnS QD. The structure of 2CEA is as follows:

[0136]

[0137] Before being added to the initial ink composition, the 2CEA crosslinkable ligand was dried on a molecular sieve to remove residual moisture and filtered through a 0.45 μm PTFE membrane filter. These two 2CEA-containing ink compositions were used as the base ink compositions subsequently added to the QD (Quick Dip) system. The formulations of these two base ink compositions are shown below. Figure 27 The table shows the results. The jetting properties and film-forming properties of both ink compositions were tested again, and they were found to be inkjet printable. Of these two ink compositions, the one containing 1,6-hexanediol diacrylate was selected to verify the introduction of QD into ink compositions for inkjet printing.

[0138] Prior to the addition of QD, the ink composition was purged with nitrogen for 30 minutes and transferred to a nitrogen glove box. All further preparation steps were performed in a nitrogen glove box. To prepare the QD-containing ink composition, a toluene stock solution of 25 mg / ml octadecylamine-terminated core-shell CdSe / ZnS QD was dispersed in anhydrous toluene by sonication for 5 minutes and filtered through a 0.45 μm PTFE membrane filter. The toluene QD stock solution was added to the base ink composition containing 1,6-hexanediol diacrylate in an amount sufficient to provide a final QD-containing ink composition with a QD concentration of 1% by weight (after toluene removal – see below). The mixture was stirred for 30 minutes to ensure uniform distribution of QD in the ink composition. The composition was sealed in a diaphragm vial and removed from the glove box. Toluene was removed from the ink composition by nitrogen purging for 30 minutes, followed by vacuum drying for 30 minutes to remove residual solvent. Alternatively, QD can be added directly to the base ink composition as a drying material (without preparing a stock solution) and ultrasonically treated to ensure uniform QD dispersion, provided that the selected QD has good solubility in the polymer component of the composition.

[0139] Two QD-containing ink compositions were prepared from a base ink composition containing 1,6-hexanediol diacrylate. A red-emitting QD was used in the first QD-containing ink composition, and a green-emitting QD was used in the second QD-containing ink composition. The formulations of these two QD-containing ink compositions, as well as their room temperature surface tension and viscosity, are shown in [Figure / Formula omitted]. Figure 28 The table shows the spraying and film-forming behavior of the two ink compositions. A Dimatix printer was used to test these properties. Both ink compositions were printed onto UVO-treated SiN... x While the surface appearance was not found to be inkjet printable, the ink composition containing red emission QD exhibited more stable jetting properties. The printed layer was cured for 1 minute under nitrogen atmosphere with 395 nm excitation. Notably, both ink compositions retained their red and green photoluminescence upon irradiation with 405 nm light after incorporation into the base ink composition and after printing and curing.

[0140] Example 2 This embodiment illustrates the use of an ink composition containing QD and PSNP for inkjet printing a light-emitting layer with enhanced light output.

[0141] An initial ink composition was prepared by mixing 1,6-hexanediol diacrylate, PET, and TPO in appropriate amounts to provide an ink composition containing 89 wt% 1,6-hexanediol diacrylate, 7 wt% PET, and 4 wt% TPO. The ink composition was formulated by mixing the three components overnight and filtering the mixture through a 0.45 μm PTFE membrane filter. Prior to addition of QD, the ink composition was purged with nitrogen for 30 minutes and transferred to a nitrogen glove box. All further preparation steps were performed in a nitrogen glove box.

[0142] To prepare the QD-containing ink composition, a toluene stock solution of 25 mg / ml end-capped core-shell InP / ZnS QD was dispersed in anhydrous toluene by sonication for 5 minutes and filtered through a 0.45 μm PTFE membrane filter. The toluene QD stock solution was added to the base ink composition containing 1,6-hexanediol diacrylate in an amount sufficient to provide a final QD-containing ink composition with a QD concentration of 1% by weight (after toluene removal – see below). The mixture was stirred for 30 minutes to ensure uniform distribution of QD in the ink composition. The composition was sealed in a diaphragm vial and removed from a glove box. Toluene was removed from the ink composition by nitrogen purging for 30 minutes, followed by vacuum drying for 30 minutes to remove residual solvent. Two QD-containing ink compositions were prepared. Red-emitting QD was used in the first QD-containing ink composition, and green-emitting QD was used in the second QD-containing ink composition.

[0143] To prepare a PSNP-containing ink composition, a dispersion of silver nanoparticles (AgNP-PSNP) in water (Nanogap Inc., Richmond, CA) was added to a base ink composition containing 1,6-hexanediol diacrylate in an amount sufficient to provide a final AgNP-containing ink composition with a concentration of 0.05% by weight. The nominal particle size of the AgNP was in the range of about 50 nm to about 80 nm. The AgNP dispersion was sonicated for 2 minutes before being added to the base ink composition.

[0144] To form a printed layer containing QD and AgNP, an AgNP-containing ink composition and a QD-containing ink composition were sequentially inkjet printed onto a glass substrate in air using a Dimatix printer at a drop volume of 10 pL. During this process, a first layer of the AgNP-containing ink composition was deposited on the glass substrate, and a second layer of the QD-containing ink composition was deposited on top of the first layer. The first layer remained uncured prior to the deposition of the second layer, allowing the printed ink compositions to blend and provide a single blend layer containing both QD and PSNP. The final blend layer was then cured for 1 minute under nitrogen atmosphere with 395 nm excitation.

[0145] In inkjet printing of PSNP-containing ink compositions, the volume printed per unit surface area increases from one edge of the printed layer to the other. In inkjet printing of QD-containing ink compositions, the volume printed per unit surface area remains constant throughout the printing process. Specifically, the volume of PSNP-containing ink composition delivered to the initial edge of the layer is sufficient to provide a 2 μm thick printed layer. This volume gradually increases until the volume of PSNP-containing ink composition delivered to the final edge of the layer is sufficient to provide a 20 μm thick printed layer. The volume of QD-containing ink composition delivered over the entire length of the layer is sufficient to provide a 6 μm thick printed layer. It is worth noting that although the edge-to-edge thickness variation of the printed film is somewhat normalized as the two printed layers are blended into a single layer, the thickness variation after curing will be partially retained to some extent.

[0146] The photoluminescence properties of a cured layer containing AgNP plasmon scatterers in combination with green emitting QDs, a cured layer containing only green emitting QDs without any PSNPs, a cured layer containing AgNP plasmon scatterers in combination with red emitting QDs, and a cured layer containing only red emitting QDs without any PSNPs were measured. Measurements were performed using an Oceanoptics Flame-S-VIS-NIR fluorometer at an excitation wavelength of 405 nm. The light intensity was integrated over a 100 ms time interval, and the resulting detector counts were used to compare the emission intensity. The emission spectra of the layer containing AgNP plasmon scatterers in combination with green emitting QDs and the layer containing only green emitting QDs without any PSNPs were obtained. Figure 29A The emission spectra of layers containing AgNP plasma scatterers in combination with red-emitting QDs and layers containing only red-emitting QDs without any PSNPs are shown in [the diagram]. Figure 29B The emission spectra of PSNP-containing layers were measured at different layer thicknesses, as shown in the figure. Figure 29A and 29B As shown in the graph, adding PSNPs to the QD-containing layer significantly increased the photoluminescence intensity of the two PSNP-containing layers—more than 4 times that of the green-emitting QD layer and more than 6 times that of the red-emitting QD layer, relative to their corresponding QD-only layers.

[0147] This teaching is intended to be illustrative and not restrictive. The abstract is provided to comply with 37 C. FR § 1.72(b) to allow the reader to quickly determine the nature of the technical disclosure. It should be understood at the time of submission that it is not intended to construe or limit the scope or meaning of the claims. Moreover, in the detailed description above, various features may be combined together to simplify this disclosure. This should not be construed as an intention that any unclaimed disclosed feature is essential to any claim. Rather, the subject matter of the invention may lie in fewer than all features of a particular disclosed embodiment. Therefore, the following claims are incorporated into the detailed description as embodiments or embodiments, each claim being an independent embodiment, and such embodiments are contemplated to be combined or interchanged with each other in various combinations or substitutions. The scope of the invention should be determined by reference to the appended claims and the full scope of the equivalents conferred by those claims.

Claims

1. A photonic device comprising: a photonic device substrate; and a crosslinked polymer film formed from an ink composition for a color filter on the photonic device substrate, the ink composition comprising: 50 to 90 weight percent of a polymeric chain comprising a polymerized di(meth)acrylate monomer, or a combination of a polymerized di(meth)acrylate monomer and a mono(meth)acrylate monomer; 4 to 10 weight percent of a polymerized multifunctional (meth)acrylate monomer crosslinking the polymeric chain; 5 to 50 weight percent of a quantum dot; and a scattering nanoparticle.

2. The photonic device of claim 1, wherein the photonic device substrate is a light guide plate and the photonic device is a liquid crystal display device.

3. The photonic device of claim 1, wherein the crosslinked polymer film is in a sub-pixel cell of a color filter and the photonic device is a liquid crystal display device.

4. The photonic device of claim 3, wherein the color filter comprises: a plurality of sub-pixel cells defined in a pixel bank; a plurality of light emitting sub-pixels comprising a plurality of red light emitting sub-pixels, a plurality of green light emitting sub-pixels, and a plurality of blue light emitting sub-pixels, each of the light emitting sub-pixels disposed in one of the sub-pixel cells; wherein each of the red light emitting sub-pixels comprises a red light emitting layer and a local filter layer comprising a light absorber disposed on a light emitting surface of the red light emitting layer; and wherein each of the green light emitting sub-pixels comprises a green light emitting layer and a local filter layer comprising a light absorber disposed on a light emitting surface of the green light emitting layer, wherein the crosslinked polymer film is a red light emitting layer, a green light emitting layer, and / or a local filter layer.

5. The photonic device of claim 1, wherein the crosslinked polymer film further comprises a ligand bound to the quantum dot, wherein the ligand is crosslinked to the polymeric chain.

6. The photonic device of claim 1, wherein the polymerized di(meth)acrylate monomer or the combination of a polymerized di(meth)acrylate monomer and a mono(meth)acrylate monomer comprises a polymerized 1,6-hexanediol di(meth)acrylate monomer.

7. The photonic device of claim 1, wherein the polymerized di(meth)acrylate monomer or the combination of a polymerized di(meth)acrylate monomer and a mono(meth)acrylate monomer comprises a polymerized propoxylated neopentyl glycol diacrylate monomer.

8. The photonic device of claim 1, wherein the polymerized di(meth)acrylate monomer or the combination of a polymerized di(meth)acrylate monomer and a mono(meth)acrylate monomer comprises a polymerized 1,12-dodecanediol di(meth)acrylate monomer.

9. The photonic device of claim 1, wherein the polymerized di(meth)acrylate monomer or the combination of a polymerized di(meth)acrylate monomer and a mono(meth)acrylate monomer comprises a polymerized polyethylene glycol di(meth)acrylate monomer.

10. The photonic device of claim 1, wherein the polymerized polyfunctional (meth)acrylate monomer comprises a polymerized tri(meth)acrylate monomer, a polymerized tetra(meth)acrylate monomer, or a combination thereof.

11. The photonic device of claim 1, wherein, The scattering nanoparticles are metal oxide nanoparticles.

12. The photonic device of claim 11, wherein the metal oxide nanoparticles are zirconium oxide, titanium oxide, or aluminum oxide.

13. The photonic device of claim 1, wherein the scattering nanoparticles are metal nanoparticles.

14. The photonic device of claim 13, wherein the metal nanoparticles comprise silver nanoparticles.

15. The photonic device of claim 1, wherein the photonic device is an organic light emitting diode.

16. A photonic device, comprising: a photonic device substrate; and a crosslinked polymer film formed from an ink composition on the photonic device substrate, the ink composition comprising: 70 to 96 weight percent of polymer chains comprising polymerized di(meth)acrylate monomers, or a combination of polymerized di(meth)acrylate monomers and mono(meth)acrylate monomers; 4 to 10 weight percent of polymerized polyfunctional (meth)acrylate monomers that crosslink the polymer chains; 0.1 to 5 weight percent of quantum dots; and 0.01 to 5 weight percent of plasmonic scattering nanoparticles.

17. The photonic device of claim 16, wherein the ink composition comprises 0.01 to 1 weight percent of the plasmonic scattering nanoparticles.

18. The photonic device of claim 17, wherein the plasmonic scattering nanoparticles comprise silver nanoparticles.

19. A photonic device, comprising: a photonic device substrate; and a crosslinked polymer film formed from an ink composition on the photonic device substrate, the ink composition comprising: 70 to 96 weight percent of polymer chains comprising polymerized di(meth)acrylate monomers, or a combination of polymerized di(meth)acrylate monomers and mono(meth)acrylate monomers; 4 to 10 weight percent of polymerized polyfunctional (meth)acrylate monomers that crosslink the polymer chains; 0.1 to 5 weight percent of quantum dots; and 0.01 to 12 weight percent of geometric scattering nanoparticles.

20. The photonic device of claim 16 or 19, wherein the crosslinked polymer film is in a sub-pixel cell of a color filter, and the photonic device is a liquid crystal display device.

21. The photonic device of claim 20, wherein the color filter comprises: a plurality of sub-pixel cells defined in a pixel bank; and a plurality of light-emitting sub-pixels comprising a plurality of red light-emitting sub-pixels, a plurality of green light-emitting sub-pixels, and a plurality of blue light-emitting sub-pixels; each light-emitting sub-pixel disposed in one of the sub-pixel cells; wherein each red light-emitting sub-pixel comprises a red light-emitting layer and a partial filter layer comprising a light absorber disposed on a light-emitting surface of the red light-emitting layer, and wherein each green light-emitting sub-pixel comprises a green light-emitting layer and a partial filter layer comprising a light absorber disposed on a light-emitting surface of the green light-emitting layer, and wherein each blue light-emitting sub-pixel comprises a blue light-emitting layer and a partial filter layer comprising a light absorber disposed on a light-emitting surface of the blue light-emitting layer. a green light emission layer and a partial filter layer, the partial filter layer comprising a light absorber disposed on a light emitting surface of the green light emission layer, wherein the crosslinked polymer film is a red light emission layer, a green light emission layer, and / or a partial filter layer.

22. The photonic device of claim 16 or 19, wherein the crosslinked polymer film is in a sub-pixel cell of a color filter and the photonic device is an organic light emitting diode.

23. The photonic device of claim 19, wherein the ink composition comprises: 80 to 90 weight percent of polymer chains comprising polymerized di(meth)acrylate monomers, or a combination of polymerized di(meth)acrylate monomers and mono(meth)acrylate monomers; and 0.5 to 2 weight percent of quantum dots.

24. A photonic device comprising: a photonic device substrate; and a crosslinked polymer film of a color filter formed from an ink composition on the photonic device substrate, the ink composition comprising: 50 to 90 weight percent of polymer chains comprising polymerized di(meth)acrylate monomers, or a combination of polymerized di(meth)acrylate monomers and mono(meth)acrylate monomers; 4 to 10 weight percent of polymerized multifunctional (meth)acrylate monomers crosslinking the polymer chains; and 5 to 50 weight percent of quantum dots.

25. The photonic device of claim 24, wherein the photonic device substrate is a light guide plate and the photonic device is a liquid crystal display device.

26. The photonic device of claim 24, wherein the crosslinked polymer film is in a sub-pixel cell of a color filter and the photonic device is a liquid crystal display device.

27. The photonic device of claim 26, wherein the color filter comprises: a plurality of sub-pixel cells defined in a pixel bank; and a plurality of light emitting sub-pixels comprising a plurality of red light emission sub-pixels, a plurality of green light emission sub-pixels, and a plurality of blue light emission sub-pixels, each light emitting sub-pixel disposed in one of the sub-pixel cells; wherein each red light emission sub-pixel comprises: a red light emission layer and a partial filter layer, the partial filter layer comprising a light absorber disposed on a light emitting surface of the red light emission layer, and wherein each green light emission sub-pixel comprises: a green light emission layer and a partial filter layer, the partial filter layer comprising a light absorber disposed on a light emitting surface of the green light emission layer, wherein the crosslinked polymer film is a red light emission layer, a green light emission layer, and / or a partial filter layer.

28. The photonic device of claim 24, wherein the crosslinked polymer film further comprises a ligand bound to the quantum dots, wherein the ligand crosslinks with the polymer chains.

29. The photonic device of claim 24, wherein the polymerized di(meth)acrylate monomers or the combination of polymerized di(meth)acrylate monomers and mono(meth)acrylate monomers comprises polymerized 1,6-hexanediol di(meth)acrylate monomers.

30. The photonic device of claim 24, wherein the polymerized di(meth)acrylate monomer or the combination of polymerized di(meth)acrylate monomer and mono(meth)acrylate monomer comprises polymerized propoxylated neopentyl glycol diacrylate monomer.

31. The photonic device of claim 24, wherein the polymerized di(meth)acrylate monomer or the combination of polymerized di(meth)acrylate monomer and mono(meth)acrylate monomer comprises polymerized 1,12-dodecanediol di(meth)acrylate monomer.

32. The photonic device of claim 24, wherein the polymerized di(meth)acrylate monomer or the combination of polymerized di(meth)acrylate monomer and mono(meth)acrylate monomer comprises polymerized polyethylene glycol di(meth)acrylate monomer.

33. The photonic device of claim 24, wherein the polymerized multifunctional (meth)acrylate monomer comprises polymerized tri(meth)acrylate monomer, polymerized tetra(meth)acrylate monomer, or a combination thereof.

34. The photonic device of claim 24, wherein the photonic device is an organic light emitting diode.

35. The photonic device of claim 24, wherein the ink composition comprises: 80 to 90 weight percent of a polymer chain comprising a polymerized di(meth)acrylate monomer, or a combination of polymerized di(meth)acrylate monomer and mono(meth)acrylate monomer; and 0.5 to 2 weight percent of a quantum dot.

36. A photonic device comprising: a photonic device substrate; and a crosslinked polymer film formed from an ink composition on the photonic device substrate, the ink composition comprising: 70 to 96 weight percent of a polymer chain comprising a polymerized di(meth)acrylate monomer, or a combination of polymerized di(meth)acrylate monomer and mono(meth)acrylate monomer; 4 to 10 weight percent of a polymerized multifunctional (meth)acrylate monomer crosslinking the polymer chain; and 0.01 to 5 weight percent of a plasmonic scattering nanoparticle.

37. The photonic device of claim 36, wherein the ink composition comprises 0.01 to 1 weight percent of the plasmonic scattering nanoparticle.

38. The photonic device of claim 37, wherein the plasmonic scattering nanoparticle comprises a silver nanoparticle.

39. A photonic device comprising: a photonic device substrate; and a crosslinked polymer film formed from an ink composition on the photonic device substrate, the ink composition comprising: 70 to 96 weight percent of a polymer chain comprising a polymerized di(meth)acrylate monomer, or a combination of polymerized di(meth)acrylate monomer and mono(meth)acrylate monomer; 4 to 10 weight percent of a polymerized multifunctional (meth)acrylate monomer crosslinking the polymer chain; 0.1 to 5 weight percent of a quantum dot; and 0.01 to 5 weight percent of a plasmonic scattering nanoparticle. 0.01 to 12 weight percent of geometric scattering nanoparticles, the geometric scattering nanoparticles comprising metal oxide nanoparticles.

40. The photonic device of claim 39, wherein the metal oxide nanoparticles comprise zirconium oxide, titanium oxide, or aluminum oxide.

41. The photonic device of claim 36 or 39, wherein the crosslinked polymer film is in a sub-pixel cell of a color filter and the photonic device is a liquid crystal display device.

42. The photonic device of claim 41, wherein the color filter comprises: a plurality of sub-pixel cells defined in a pixel bank; and a plurality of light emitting sub-pixels comprising a plurality of red light emitting sub-pixels, a plurality of green light emitting sub-pixels, and a plurality of blue light emitting sub-pixels; each light emitting sub-pixel disposed in one of the sub-pixel cells; wherein each red light emitting sub-pixel comprises: a red light emitting layer and a local filter layer, the local filter layer comprising a light absorber disposed on a light emitting surface of the red light emitting layer; and wherein each green light emitting sub-pixel comprises: a green light emitting layer and a local filter layer, the local filter layer comprising a light absorber disposed on a light emitting surface of the green light emitting layer, wherein the crosslinked polymer film is a red light emitting layer, a green light emitting layer, and / or a local filter layer.

43. The photonic device of claim 36 or 39, wherein the crosslinked polymer film is in a sub-pixel cell of a color filter and the photonic device is an organic light emitting diode.

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