Articles including nanostructured surfaces and enclosed voids

Abstract

This disclosure provides an article comprising: at least two layers, each having at least one closed void, the closed void being partially defined by a nanostructured surface; or a single layer having at least one closed void, the closed void being defined by two nanostructured surfaces in contact with each other. Furthermore, this disclosure provides an optical information display and an OLED device including the article. The nanostructured surface of the article is protected from damage and contamination by the presence of the other layer.

Description

Technical Field

[0001] This disclosure relates broadly to articles including nanostructured surfaces and methods for manufacturing such articles. Prior Technology

[0002] Nanostructured surfaces can provide optical effects for a variety of applications, such as improving the color and performance of devices (e.g., OLED displays). A refractive index difference or refractive index contrast is required at the nanostructured interface to provide the desired optical functionality. Nanostructured surfaces can be exposed to the surrounding environment to provide refractive index contrast; however, the exposed surface limits its adhesion to other surfaces and is susceptible to damage and / or contamination from the environment. Therefore, improvements are still needed in protecting nanostructured surfaces. Summary of the Invention

[0003] In a first embodiment, an article is provided. The article includes a) a first layer comprising a nanostructured first surface having nano-features and an opposing second surface. The nanostructured first surface has a recessed feature, or a protruding feature, or both recessed and protruding features formed from a single component; and b1) or b2). b1) is a second layer comprising a first main surface and an opposing second main surface, the first main surface being attached to a portion of the nano-features of the first layer. The nanostructured first surface of the first layer and the first main surface of the second layer together define at least a first void. b2) is a third layer comprising a nanostructured first surface having nano-features and an opposing second surface, wherein a portion of the nano-features of the third layer is attached to a portion of the nano-features of the first layer. The nanostructured first surface of the third layer and the nanostructured first surface of the first layer together define at least a second void. The article includes the following condition: when b1) is present, the article further includes c) a fourth layer, the fourth layer including a nanostructured first surface having a nano-characteristic and an opposing second surface. The second surface of the fourth layer or the nanostructured first surface of the fourth layer is adjacent to the second main surface of the second layer or adjacent to the second surface of the first layer.

[0004] In a second state, an optical information display is provided, which includes an article according to the first state.

[0005] In a third state sample, an OLED device is provided, which includes an article according to the first state sample.

[0006] Articles according to at least some embodiments of the present disclosure provide an enclosure for a nanostructured surface that protects the nanostructured surface and maintains the refractive index contrast of the air interface, as well as optical effects different from those provided by a single nanostructured surface with multiple closed voids.

[0007] The above description of the invention is not intended to describe each of the disclosed embodiments or implementations. The following embodiments illustrate illustrative examples in more detail. Examples are provided in several places throughout this application by way of a list of examples, which can be used in various combinations. In all cases, the cited lists are intended as representative groups only and should not be construed as exclusive lists. Simple Explanation of the Diagram

[0008] [Figure 1] is a schematic cross-sectional view of an exemplary article according to one of the claims. [Figure 2] is a schematic cross-sectional view of another exemplary article according to this application. [Figure 3A] is a schematic cross-sectional view of a further illustrative article according to this application. [Figure 3B] is a schematic cross-sectional view of one of the OLED structures in Examples 1 to 4 and Comparative Examples 1 to 2 of this application. [Figure 4A] is a schematic cross-sectional view of an exemplary article according to Example 1 of this application. [Figure 4B] is a scanning electron microscopy (SEM) image of a cross-section of an exemplary article according to Example 1 of this application. [Figure 5A] is a schematic cross-sectional view of an exemplary article according to Example 2 of this application. [Figure 5B] is a SEM image of a cross-section of an exemplary article according to Example 2 of this application. [Figure 5C] is a SEM image of the upper section of the exemplary article according to Example 2 of this application. [Figure 5D] is a SEM image of the lower part of the exemplary article according to Example 2 of this application. [Figure 6A] is a schematic cross-sectional view of an exemplary article according to Example 3 of this application. [Figure 6B] is a SEM image of a cross-section of an exemplary article according to Example 3 of this application. [Figure 6C] is a SEM image of the upper section of the exemplary article according to Example 3 of this application. [Figure 6D] is a SEM image of the lower section of the exemplary article according to Example 3 of this application. [Figure 7A] is a schematic cross-sectional view of an exemplary article according to Example 4 of this application. [Figure 7B] is a SEM image of a cross-section of an exemplary article according to Example 4 of this application. [Figure 7C] is a SEM image of the upper section of the exemplary article according to Example 4 of this application. [Figure 7D] is a SEM image of the lower part of the exemplary article according to Example 4 of this application. [Figure 8] is a top-view SEM image of one of the nanostructured surfaces of membrane A prepared according to this application. [Figure 9A] is a SEM image of a cross-section of a nanostructured surface prepared according to this application. [Figure 9B] is a top-view SEM image of one of the nanostructured surfaces of the membrane D prepared according to this application. [Figure 10A] is a perspective SEM image of a nanostructured surface prepared according to this application. [Figure 10B] is a perspective SEM image of one of the nanostructured surfaces of the membrane E prepared according to this application. [Figure 11A] is a top view schematic diagram of yet another exemplary article according to this application. [Figure 11B] is a SEM image of a section of an exemplary article according to Example 6 of this application. [Figure 12A] is a top-view SEM image of a portion of the first layer of the nanostructured structure according to this application, which includes the grooved nano features of the structured sample B. [Figure 12B] is a SEM image of a section of an exemplary article according to Example 7 of this application.

[0009] While the foregoing figures illustrate several embodiments of this disclosure, other embodiments mentioned herein are contemplated. The figures are not necessarily drawn to scale. In all cases, the manner in which this disclosure presents the invention is representative and not restrictive. It should be understood that those skilled in the art can devise many other modifications and embodiments, which still fall within the scope and spirit of the invention. Implementation vocabulary

[0010] As used in this article, the term "adjacent" means that a material or layer can be in contact with another material or layer (i.e., directly adjacent), or separated from another material or layer by an intermediate material, layer, or gap.

[0011] As used herein, the term "colorant" refers to a component that imparts color, including, for example, pigments, dyes, and combinations thereof. As used herein, the term "pigment" refers to a material whose loading exceeds its solubility, resulting in insoluble (or non-soluble) particles.

[0012] The phrase "forming a planar contact" is used to indicate that one layer or layered structure is in contact with another layer or layered structure (and is disposed on or below it). This type of contact is a surface contact, not an edge contact.

[0013] As used herein, the term "organic layer" means a layer comprising, for example, more than 50% by weight, one or more materials including hydrocarbons or their halogenated analogs, a three-dimensional continuous polymer matrix, or both.

[0014] As used herein, the term "inorganic layer" refers to a layer comprising most (e.g., more than 50% by weight) one or more compounds lacking carbon-hydrogen bonds or their halogenated analogues.

[0015] As used in this article, "nanostructured" refers to a surface with a morphology in the form of nano-features, wherein the nano-features include the material defining the surface, and wherein either the height or the width of the nano-feature is less than about 1 micron (i.e., 1 micrometer or 1000 nanometers).

[0016] As used herein, "index of refraction" refers to the refractive index of a material in its plane relative to light incident normally at 633 nm, unless otherwise specified.

[0017] As used herein, "gas" means any material that is in the gaseous phase at standard temperature and pressure (i.e., 0 degrees Celsius and 105 Pascals).

[0018] As used herein, "birefringence" means that the refractive indices are not identical in the orthogonal x, y, and z directions. The refractive indices for the x, y, and z directions are designated as nx, ny, and nz, respectively. For the layer described herein, the axes are chosen such that the x and y axes lie in the plane of the layer, and the z-axis is normal to the plane of the layer and generally corresponds to the thickness or height of the layer. When the refractive index in one direction within the plane is greater than that in another direction within the plane, the direction with the highest refractive index is typically chosen as the x-axis.

[0019] As used herein, "transparent to visible light" means that the transmittance of an unpatterned substrate or article to at least one polarization state of visible light is 60% or higher, 70% or higher, 80% or higher, 90% or higher, 95% or higher, or 98% or higher, where the transmittance percentage is normalized to the intensity of the incident light (optionally polarized light). The term "visible" combined with "transparent to visible light" modifies the term "light" to specify the wavelength range of light to which the article is transparent.

[0020] In this application, the terms "preferred" and "preferably" used in the embodiments disclosed herein indicate that certain benefits may be provided in certain circumstances. However, other embodiments may also be preferred under the same or other circumstances. Furthermore, reference to one or more preferred embodiments does not imply that other embodiments are not useful, nor is it intended to exclude other embodiments from the scope of this disclosure.

[0021] The terms "a / an" and "the" are intended not only to refer to a singular entity but also to include specific instances that can be used as a general category for description. The terms "a / an" and "the" can be used interchangeably with "at least one." The phrases "at least one of" and "comprise at least one of," used after a list, refer to any one item in the list or any combination of two or more items in the list.

[0022] As used in this article, unless otherwise explicitly stated in the text, the word "or" usually includes the meaning of "and / or".

[0023] The term "and / or" means one or all of the listed elements, or any combination of two or more of the listed elements.

[0024] Similarly, throughout this document, all figures are assumed to be modified by the term "about" and preferably by the term "exactly." As used herein, the term "about," in conjunction with the measured quantity, refers to a change in that measured quantity as would be expected by a technician performing the measurement with a degree of care commensurate with the accuracy of the measurement target and the measuring equipment used. Also throughout this document, the range of figures described with endpoints includes all figures falling within that range as well as figures described with endpoints (e.g., 1 to 5 includes 1, 1.5, 2, 2.75, 3, 3.80, 4, 5, etc.).

[0025] As used herein, the term "generally" as a modifier of a characteristic or attribute, unless otherwise specifically defined, means that the characteristic or attribute can be easily identified by someone of ordinary skill in the art, but does not require absolute precision or a perfect match (e.g., within + / - 20% of a quantifiable characteristic). Unless otherwise specifically defined, the term "substantially" indicates a high degree of approximation (e.g., within + / - 10% of a quantifiable characteristic), but similarly does not require absolute precision or a perfect match. It should be understood that terms such as identical, equal, consistent, constant, absolute, and similar apply to specific situations within common tolerances or measurement errors, and do not require absolute precision or a perfect match.

[0026] As used herein, the designations "first," "second," "third," etc., to refer to features are used only to clearly distinguish which feature is described in a particular embodiment. The order of features may vary between different embodiments; for example, "second layer" in one embodiment may be referred to as "third layer" in different embodiments, where the second layer describes different structures and / or materials. thing

[0027] In a first-state sample, an item is provided. The item comprises: a) A first layer comprising a nanostructured first surface including nano-features and an opposing second surface, wherein the nanostructured first surface includes a groove-like feature, or a protruding feature, or both groove-like and protruding features formed of a single component; and any of the following: b1) A second layer comprising a first main surface and an opposing second main surface, the first main surface being attached to a portion of the nanostructures of the first layer, wherein the nanostructured first surface of the first layer and the first main surface of the second layer together define at least a first void; or b2) A third layer comprising a nanostructured first surface including one of the nano-features and an opposing second surface, wherein a portion of the nano-features of the third layer is attached to a portion of the nano-features of the first layer, and wherein the nanostructured first surface of the third layer and the nanostructured first surface of the first layer together define at least one second void; The condition is that, if b1) exists, the item further includes: c) A fourth layer comprising a nanostructured first surface containing nano-features and a corresponding second surface. The second surface of the fourth layer or the nanostructured first surface of the fourth layer is adjacent to the second main surface of the second layer or the second surface of the first layer.

[0028] It has been found that it is possible to form each of the following: 1) an article containing at least two layers, each layer comprising one or more voids defined by a nanostructured surface (sometimes referred to as a single-layer encapsulation) in contact with a substantially flat surface; and 2) an article containing one or more voids defined by two nanostructured surfaces in contact with each other (sometimes referred to as a double-layer encapsulation). Articles comprising combinations of the features of 1) and 2) are also provided. The articles exhibit a refractive index difference, wherein the nanostructured surface is protected from damage or contamination. Furthermore, these articles provide optical properties different from those comprising a single layer containing one or more voids defined by a nanostructured surface and a substantially flat surface.

[0029] Figure 1 is a schematic cross-sectional view of an exemplary article 1000 that can be prepared according to this application. Article 1000 includes: a first layer 110, which includes a nanostructured first surface 112 containing nano-features 114 and an opposing second surface 116; and a second layer 120, which includes a nanostructured first surface 122 containing nano-features 124 and an opposing second surface 126. A portion of the nano-features 124 of the second layer 120 is attached to a portion of the nano-features 114 of the first layer 110. Optionally, all nano-features of one layer are attached to a portion of the nano-features of the other layer, or all nano-features of the two layers are attached to each other. The nanostructured first surface 122 of the second layer 120 and the nanostructured first surface 112 of the first layer 110 together define at least a first void 100 (e.g., in the form of a negative space between the first layer 110 and the second layer 120). The (multiple) cavities 100 are not filled with solids or liquids, but contain a vacuum or gas. Suitable gases include, for example, ambient air (e.g., the atmosphere in its natural state), gases, or gas mixtures (e.g., 90% nitrogen and 10% oxygen). In some embodiments, suitable gases may include at least one inert gas (e.g., nitrogen, argon, helium, xenon, etc.).

[0030] In the embodiment shown in FIG1, each of the nanostructured first surface 112 of the first layer 110 and the nanostructured first surface 122 of the second layer 120 includes protruding features 119 and 129, respectively. In any article according to this disclosure, the nanostructured first surface may optionally include a grooved feature, or a protruding feature, or both grooved and protruding features formed of a single composition. "Single composition" means that the protruding feature is made of the same material throughout the protruding feature, rather than including a portion of a feature with a different composition from another portion of the same feature. In some embodiments, the protruding feature has the same composition as (e.g., most of) the first layer 110. In some embodiments, the grooved feature is defined by a structure (e.g., the first layer) formed of a single composition. In some embodiments, the composition may be, for example, a polymer, a polymer blend, and / or a polymer matrix containing nanoparticles dispersed in a polymer matrix. In some embodiments, the composition may be, for example, an inorganic material. The advantage of protruding features composed of a single component is that such protruding features can often be formed by relatively simple nano-replication methods, such as the description of film A in the examples below. In embodiments in which all nano-features are grooved features, the attachment of a portion of the nano-features of the second layer to a portion of the nano-features of the first layer means that at least a portion of the grooved features of each layer collectively defines the void (e.g., the boundary of the void is formed by the grooved features of the first and second layers respectively).

[0031] The article 1000 of Figure 1 further includes: a third layer 130, which includes a nanostructured first surface 132 comprising nano-features 134 and an opposing second surface 136; and a fourth layer 140, which includes a first main surface 142 and an opposing second main surface 144 attached to a portion of the nano-features 134. In this embodiment, the nano-features 134 are recessed features 137, and a plurality of gaps 135 are defined by the first main surface 142 of the fourth layer 140 and the nano-features 134 of the third layer 130. In this embodiment, the opposing second surface 136 of the third layer 130 is attached to the opposing second surface 126 of the second layer; however, it is contemplated that the third layer may be attached (directly or indirectly) to the opposing second surface 116 of the first layer 110.

[0032] Any number of additional layers can be used in combination with one or more layers defining closed voids to provide, for example, structural integrity, adhesion, further optical effects, etc. The location of each additional layer is not particularly limited, but can be chosen as desired. For example, the article 1000 of FIG. 1 further includes a fifth layer 150 attached to the fourth layer 140, wherein a first primary surface 152 of the fifth layer 150 is attached to the second primary surface 144 of the fourth layer. The article 1000 further includes a sixth layer 160 attached to the opposite second surface 116 of the first layer 110.

[0033] Referring now to Figure 2, which provides a schematic cross-sectional view of an exemplary article 2000 according to this application. Article 2000 includes: a first layer 210 comprising a nanostructured first surface 212 including nano-features 214 and an opposing second surface 216; and a second layer 220 comprising a first main surface 222 attached to a portion of the nano-features 214 and an opposing second main surface 224. In this embodiment, the nano-features 214 are protruding features 219, and a plurality of voids 200 are defined by the first main surface 222 of the second layer 220 and the nano-features 214 of the first layer 210. Article 2000 further comprises: a third layer 230 including a nanostructured first surface 232 comprising nano-features 234 and an opposing second surface 236; and a fourth layer 240 including a first main surface 242 attached to a portion of the nano-features 234 and an opposing second main surface 244. In the embodiment shown in FIG2, the nanostructured first surface 232 of the third layer 230 includes both recessed features 237 and protruding features 239. Alternatively, an article may include only one of recessed features 237 or protruding features 239, as seen in FIG1. ​​In some embodiments, a connection gap exists surrounding many, most, or all of the protruding nano-features of a nanostructured surface that includes only protruding features. The advantage of using only recessed features is that the second layer can contact one of the main surfaces of the first layer rather than the tops of several protruding features, and the resulting article may be less fragile than an article with protruding features. The embodiment shown in Figure 2 includes both individual gaps 235 extending into the recessed feature 237 and large connecting gaps 235 extending around the plurality of protruding features 239.

[0034] The embodiment shown in Figure 2 further includes a fifth layer 250, which has a first main surface 252 and a second main surface 254 attached to the opposing second surface 216 of the first layer. Article 200 also includes a sixth layer 260, which has a first main surface 262 attached to the opposing second main surface 254 of the fifth layer 250 and a second main surface 264 attached to the opposing second surface 236 of the third layer. Article 2000 shown in Figure 2 additionally includes a seventh layer 270, which has a first main surface 272 and a second main surface 274 attached to the opposing second main surface 244 of the fourth layer 240. Furthermore, article 200 includes an eighth layer 280, which has a first main surface 282 attached to the opposing second main surface 274 of the seventh layer 270. The fifth to eighth layers are shown as an example only. As described above regarding Figure 1, any number of additional layers can be used in combination with one or more layers containing closed voids to provide, for example, structural integrity, adhesion, further optical effects, etc. The placement of each additional layer is not particularly limited, but can be chosen as desired.

[0035] Referring to FIG4A, a schematic cross-sectional view of an exemplary article 4000 according to Example 1 is provided. Article 4000 includes: a first layer 410, which includes a nanostructured first surface comprising a plurality of nanofeatures 414; and a second layer 420, which includes a nanostructured first surface comprising a plurality of nanofeatures 424. At least a portion of the nanofeatures 424 of the second layer 420 is attached to at least a portion of the nanofeatures 414 of the first layer 410. The nanostructured first surface of the second layer 420 and the nanostructured first surface of the first layer 410 together define at least a first void 400. Article 4000 according to Example 1 further includes a plurality of other layers, which are located on either side of the first layer 410 and the second layer 420. Specifically, the embodiment of Figure 4A further includes: a third layer 430, which is a polymer layer; a fourth layer 440, which is a polymer layer; and a fifth layer 450, which is a release liner. The third layer 430 is directly attached to the first layer 410, the fourth layer 440 is directly attached to the third layer 430, and the fifth layer 450 is directly attached to the fourth layer 440. The embodiment of Figure 4A further includes: a sixth layer 460, which is a polymer layer; a seventh layer 470, which is a polymer layer; and an eighth layer 480, which is a release liner. The sixth layer 460 is directly attached to the second layer 420, the seventh layer 470 is directly attached to the sixth layer 460, and the eighth layer 480 is directly attached to the seventh layer 470.

[0036] Figure 4B provides a scanning electron microscope (SEM) image of a cross-section of the exemplary article prepared in Example 1 below, showing a portion of nano-features 414 and 424 of article 4000, which defines at least one void 400. In other words, the plurality of voids 400 are defined by the space between the first layer 410 and the second layer 420, wherein a portion of nano-feature 414 of the first layer 410 is attached to a portion of nano-feature 424 of the second layer 420. It should be noted that the cross-section shows a portion of the voids 400 closer to the edge than the central void 400.

[0037] Figure 5A is a schematic cross-sectional view of an exemplary article according to Example 2 of this application. Article 5000 includes: a first layer 510, which includes a nanostructured first surface including a plurality of nanofeatures 514; and a second layer 520, which includes a nanostructured first surface including a plurality of nanofeatures 524. At least a portion of the nanofeatures 524 of the second layer 520 is attached to at least a portion of the nanofeatures 514 of the first layer 510. The nanostructured first surface of the second layer 520 and the nanostructured first surface of the first layer 510 together define at least a first void 500. In addition, article 5000 includes: a third layer 530, which includes a nanostructured first surface including a plurality of nanofeatures 534; and a fourth layer 540, which includes a first main surface attached to a portion of the nanofeatures 534. In this embodiment, the nano feature 534 is a protruding feature, and the plurality of second gaps 535 are defined by the first main surface of the fourth layer 540 and the nano feature 534 of the third layer 530.

[0038] Article 5000 according to Example 2 additionally includes a plurality of other layers, including those located on either side of the first layer 510 and the second layer 520. Specifically, the embodiment of FIG5A further includes: a fifth layer 551, which is a polymer layer; a sixth layer 553, which is a polymer layer; and a seventh layer 555, which is a release liner. The fifth layer 551 is directly attached to the first layer 510, the sixth layer 553 is directly attached to the fifth layer 551, and the seventh layer 555 is directly attached to the sixth layer 553. The embodiment of FIG5A further includes an eighth layer 561, a ninth layer 563, and a tenth layer 565, each of which is a polymer layer. The eighth layer 561 is directly attached to the second layer 520, the ninth layer 563 is directly attached to the eighth layer 561, and the tenth layer 565 is directly attached to the ninth layer 563 and the fourth layer 540. Item 5000 also includes: an eleventh layer 571, which is a polymer layer; a twelfth layer 573, which is a polymer layer; and a thirteenth layer 575, which is a release liner. The eleventh layer 571 is directly attached to the third layer 530, the twelfth layer 573 is directly attached to the eleventh layer 571, and the thirteenth layer 575 is directly attached to the twelfth layer 573.

[0039] Figure 5B is a SEM image of a cross-section of the exemplary article 5000 prepared in Example 2. The portion including (multiple) first gaps 500 and (multiple) second gaps 535 is shown as blurred lines in the cross-section. Figure 5C is a SEM image of a cross-section of the upper part of the exemplary article of Example 2, in which a third layer 530, a fourth layer 540, and a plurality of gaps 535 are visible.

[0040] Similarly, Figure 5D is a SEM image of the lower section of the exemplary article of Example 2, in which the first layer 510, the second layer 520, and a plurality of gaps 500 are visible.

[0041] Figure 6A is a schematic cross-sectional view of an exemplary article according to Example 3 of this application. Article 6000 includes: a first layer 610, which includes a nanostructured first surface including a plurality of nanofeatures 614; and a second layer 620, which includes a nanostructured first surface including a plurality of nanofeatures 624. At least a portion of the nanofeatures 624 of the second layer 620 is attached to at least a portion of the nanofeatures 614 of the first layer 610. The nanostructured first surface of the second layer 620 and the nanostructured first surface of the first layer 610 together define at least a first void 600. In addition, article 6000 includes: a third layer 630, which includes a nanostructured first surface including a plurality of nanofeatures 634; and a fourth layer 640, which includes a nanostructured first surface including a plurality of nanofeatures 644. At least a portion of the nano-feature 644 of the fourth layer 640 is attached to at least a portion of the nano-feature 634 of the third layer 630. The nanostructured first surface of the fourth layer 640 and the nanostructured first surface of the third layer 630 together define at least one first void 635. In this embodiment, nano-features 634 and 644 are protruding features, and the plurality of voids 635 are defined by the first main surface of the fourth layer 640 and the nano-feature 634 of the third layer 630.

[0042] Article 6000 according to Example 3 additionally includes a plurality of other layers, including those located on either side of the first layer 610 and the second layer 620. Specifically, the embodiment of FIG6A further includes: a fifth layer 651, which is a polymer layer; a sixth layer 653, which is a polymer layer; and a seventh layer 655, which is a release liner. The fifth layer 651 is directly attached to the first layer 610, the sixth layer 653 is directly attached to the fifth layer 651, and the seventh layer 655 is directly attached to the sixth layer 653. The embodiment of FIG6A further includes an eighth layer 661, a ninth layer 663, and a tenth layer 665, each of which is a polymer layer. The eighth layer 661 is directly attached to the second layer 620, the ninth layer 663 is directly attached to the eighth layer 661, and the tenth layer 665 is directly attached to the ninth layer 663 and the fourth layer 640. Item 6000 also includes: an eleventh layer 671, which is a polymer layer; a twelfth layer 673, which is a polymer layer; and a thirteenth layer 675, which is a release liner. The eleventh layer 671 is directly attached to the fourth layer 640, the twelfth layer 673 is directly attached to the eleventh layer 671, and the thirteenth layer 675 is directly attached to the twelfth layer 673.

[0043] Figure 6B is a SEM image of a cross-section of the exemplary article prepared in Example 3. The portion including the first gap 600 and the second gap 635 is shown as blurred lines in the cross-section. Figure 6C is a SEM image of a cross-section of the upper part of the exemplary article of Example 3, in which the third layer 630, the fourth layer 640, and a plurality of gaps 635 are visible. Similarly, Figure 6D is a SEM image of a cross-section of the lower part of the exemplary article of Example 3, in which the first layer 610, the second layer 620, and a plurality of gaps 600 are visible.

[0044] Figure 7A is a schematic cross-sectional view of an exemplary article according to Example 4 of this application. Article 7000 includes: a first layer 710, which includes a nanostructured first surface comprising a plurality of nanofeatures 714; and a second layer 720, which includes a first main surface attached to a portion of the nanofeatures 714. In this embodiment, the nanofeatures 714 are protruding features, and the plurality of gaps 700 are defined by the first main surface of the second layer 720 and the nanofeatures 714 of the first layer 710. Furthermore, article 7000 includes: a third layer 730, which includes a nanostructured first surface comprising a plurality of nanofeatures 734; and a fourth layer 740, which includes a first main surface attached to a portion of the nanofeatures 734. The nanofeatures 734 are protruding features, and the plurality of gaps 735 are defined by the first main surface of the fourth layer 740 and the nanofeatures 734 of the third layer 730.

[0045] Article 7000 according to Example 4 additionally includes a plurality of other layers, including those located on either side of the first layer 710 and the second layer 720. Specifically, the embodiment of FIG7A further includes: a fifth layer 751, which is a polymer layer; a sixth layer 753, which is a polymer layer; and a seventh layer 755, which is a release liner. The fifth layer 751 is directly attached to the second layer 720, the sixth layer 753 is directly attached to the fifth layer 751, and the seventh layer 755 is directly attached to the sixth layer 753. The embodiment of FIG7A further includes an eighth layer 761, a ninth layer 763, and a tenth layer 765, each of which is a polymer layer. The eighth layer 761 is directly attached to the first layer 710, the ninth layer 763 is directly attached to the eighth layer 761, and the tenth layer 765 is directly attached to the ninth layer 763 and the third layer 530. Item 7000 also includes: an eleventh layer 771, which is a polymer layer; a twelfth layer 773, which is a polymer layer; and a thirteenth layer 775, which is a release liner. The eleventh layer 771 is directly attached to the fourth layer 540, the twelfth layer 773 is directly attached to the eleventh layer 771, and the thirteenth layer 775 is directly attached to the twelfth layer 773.

[0046] Figure 7B is a cross-sectional SEM image of the exemplary article prepared in Example 4. Figure 7C is a cross-sectional SEM image of the upper part of the exemplary article of Example 4, in which the third layer 730, the fourth layer 740, and a plurality of voids 735 are visible. Similarly, Figure 7D is a cross-sectional SEM image of the lower part of the exemplary article of Example 4, in which the first layer 710, the second layer 720, and a plurality of voids 700 are visible.

[0047] Alternatively, each of the layers may be substantially planar. As used herein, "substantially planar" means that one surface of the layer has substantially no grooves and / or protrusions extending above and / or below the plane of the layer, such grooves and / or protrusions having a depth or height greater than 100 micrometers, 90 micrometers, 80 micrometers, 70 micrometers, 60 micrometers, 50 micrometers, 40 micrometers, 30 micrometers, 25 micrometers, 20 micrometers, 15 micrometers, 10 micrometers, 9 micrometers, 8 micrometers, 7 micrometers, 6 micrometers, 5 micrometers, 4 micrometers, 3 micrometers, 2 micrometers, or greater than 1 micrometer. Generally, grooves and / or protrusions have a depth or height less than 1 millimeter, such as 900 micrometers or less, 800 micrometers, 700 micrometers, 600 micrometers, 500 micrometers, 400 micrometers, or 300 micrometers or less. The depth or height of grooves or protrusions present on the surface of a layer can be measured using a confocal microscope.

[0048] In some embodiments, a layer comprising a nanostructured first surface containing nano-features and an opposing second surface is an inorganic layer, such as a ceramic layer. For example, International Application Publication No. WO 2018 / 044565 (Humpal et al.) describes the formation of molded gels, aerogels, and sintered articles. A molded gel article is formed by pouring a sol containing surface-modified colloidal silica particles into a mold cavity, followed by polymerization of the sol to form a polymer. The molded gel retains the same size and shape as the mold cavity. Removing the organic solvent medium from the molded gel article provides an aerogel article. Heating the molded gel article to remove the organic matrix from the polymer provides a sintered article. Even if the cavity size is small, the molded gel article can replicate the features of a mold cavity. This is possible at least when the poured sol has a relatively low viscosity and contains silica particles with an average particle size of no more than 100 nanometers. Figure 12A provides a top-view SEM image of a portion of a nanostructured first layer 110, which includes grooved nanofeatures 114 in the surface 112 of the structured sample B, formed using the method described in WO 2018 / 044565.

[0049] Suitable inorganic materials are not limited to silicon oxide, but may include oxides, nitrides, carbides, or borides of metals or nonmetals, or combinations thereof. In some embodiments, the inorganic material includes oxides of titanium, indium, tin, tantalum, zirconium, niobium, aluminum, silicon, or combinations thereof. For example, suitable oxides include silicon dioxide, aluminum oxides such as aluminum oxide, titanium oxides such as titanium dioxide, indium oxide, tin oxide, indium tin oxide (ITO), hafnium oxide, tantalum oxide, zirconium oxide, niobium oxide, and combinations thereof. When an inorganic material is used as one layer of a nanostructured first surface containing one of the nano-features, the article can be used as an optical element, such as a diffraction grating.

[0050] Optionally, any or more of these layers may contain a polymeric material (i.e., a three-dimensional continuous polymeric phase). The layer may contain a crosslinked or crosslinkable material. In some embodiments, each of the first through fourth layers is an inorganic layer, such as a polymeric layer. Any or more of these layers may contain a crosslinked or crosslinkable material. Any or more of the nanostructured layers may have a refractive index, for example, in the range of 1.2 to 2.4, or in the range of 1.4 to 1.75. The refractive index refers to the refractive index measured at 632 nm, unless otherwise specified or unless the context clearly indicates otherwise. In some embodiments, one or more of the nanostructured layers have a refractive index of 1.3 or greater, 1.5 or greater, 1.6 or greater, 1.7 or greater, or 1.75 or greater; and a refractive index of 2.4 or less, 2.3 or less, 2.2 or less, 2.1 or less, or 2.0 or less. The article disclosed herein provides a refractive index contrast (the absolute value of the difference between the refractive index of the nanostructured first layer and the refractive index of the void(s)) across one of the opposing second surfaces of the first layer (e.g., at least in part due to the presence of the void(s)). In some embodiments, the refractive index contrast is in the range of 0.1 to 1.0, 0.3 to 1.0, or 0.5 to 1.0.

[0051] Nanostructures are structures having at least one dimension (such as width or height) less than 1 micrometer. Nanostructured surfaces can be fabricated using tools having a nanostructured surface. In some embodiments, the tool comprises a plurality of particles partially embedded in a substrate. Useful techniques for fabricating such tools are described in U.S. Publication No. 2014 / 0193612 (Yu et al.) and U.S. Patent No. 8,460,568 (David et al.). The nanostructured surface of the tool can be characterized by atomic force microscopy (AFM). Further details of finding useful nanostructured surfaces and methods for fabricating nanostructured surfaces can be found as described in PCT Publication No. WO 2009 / 002637A2 (Zhang et al.) and No. WO 2017 / 205174 (Freier et al.). Referring to FIG10A, a SEM of a first layer 110 is shown. The first layer 110 includes a nanostructured first surface 112, which includes nano features 114.

[0052] Examples of characteristics of nanofeatures include pitch, height, depth, aspect ratio, diameter, sidewall angle, and shape. Pitch refers to the distance between adjacent nanofeatures, typically measured from their highest point. Height refers to the height of a protruding nanofeature, measured from its bottom (in contact with the underlying layer) to its highest point. Depth refers to the depth of a recessed nanofeature, measured from its highest point (at the opening on one of the main surfaces of the layer) to its lowest point. Aspect ratio refers to the ratio of the width (widest part) of a nanofeature's cross-section to its height or depth. Diameter refers to the longest line that can be drawn across a nanofeature, from a point on its height or depth, through a center point, to an opposite surface. Sidewall angle refers to the angle formed between the sidewall of a nanofeature and the main surface of the layer in which the nanofeature protrudes or recedes. Sidewall angles can vary at different points along the height or depth of the nanofeature. Shape refers to the cross-sectional shape of the nanofeature. Optionally, the cross-sectional shape (and diameter) may vary at different points along the height or depth of the nanofeature.

[0053] As shown in Figure 10A, in some embodiments, the nanostructured first surface 112 of the first layer 110 includes nanofeatures 114 with a regular height H, while in other embodiments, the nanostructured first surface 112 of the first layer 110 includes nanofeatures 114 with different heights. This may depend on the method of forming the nanostructured surface. In any embodiment according to this disclosure, at least one dimension of the height H or width W of the nanofeature is less than 1 micrometer to provide the desired small-size feature. In some embodiments, the height H of the nano-feature (e.g., average) is less than 1 micrometer, 950 nanometers (nm) or less, 900 nm or less, 850 nm or less, 800 nm or less, 750 nm or less, 700 nm or less, 650 nm or less, or 600 nm or less; and the height H of the nano-feature is 5 nm or greater, 10 nm or greater, 20 nm or greater, 30 nm or greater, 50 nm or greater, 75 nm or greater, 100 nm or greater, 150 nm or greater, 200 nm or greater, 250 nm or greater, 300 nm or greater, 350 nm or greater, 400 nm or greater, 450 nm or greater, or 500 nm or greater. In some embodiments, the width W of the nano-feature (e.g., average) is less than 1 micrometer, 950 nanometers (nm) or less, 900 nm or less, 850 nm or less, 800 nm or less, 750 nm or less, 700 nm or less, 650 nm or less, or 600 nm or less; and the width W of the nano-feature is 5 nm or greater, 10 nm or greater, 20 nm or greater, 30 nm or greater, 50 nm or greater, 75 nm or greater, 100 nm or greater, 150 nm or greater, 200 nm or greater, 250 nm or greater, 300 nm or greater, 350 nm or greater, 400 nm or greater, 450 nm or greater, or 500 nm or greater.

[0054] Nanostructured surfaces may each include nano-columns, or nano-walls comprising nano-columns. Referring to Figures 1 and 2, in some embodiments, nano-feature 134 includes at least one non-linear surface 131 in at least one direction. For example, some nano-features 134 shown in Figure 1 have a curved surface 131 (e.g., on the lower surface of a recessed feature 134), while at least some nano-features 214 shown in Figure 2 have a curved surface 215 (e.g., on one sidewall surface of a projecting feature 214). Any shape conveniently formed by a nanoreplication process can be used for nano-features (e.g., prisms, ridges, linear and / or curved polygons). As used herein, "nanoreplication" refers to a process of molding a nanostructured surface from another nanostructured surface using, for example, a curable or thermoplastic material. Nano replication is further described, for example, in "Micro / Nano Replication", Shinill Kang, John Wiley & Sons, Inc., 2012, Chapters 1 and 5-6. Nano features may optionally have steep sidewalls that are generally perpendicular to the opposing second surface of the first or second layer. For example, referring to FIG1, some nano features 114 have steep sidewalls 111 that are generally perpendicular to the opposing second surface 116 of the first layer 110.

[0055] Referring to FIG8, some individual nanofeatures 114 may be equidistant along one direction D1 of the nanostructured first surface 112, but not along an orthogonal direction D2. In some embodiments, some individual nanofeatures 114 are equidistant along at least two directions D1 and D2 of the nanostructured first surface 112 (not shown). Referring to FIG9A, some individual nanofeatures 114 are not equidistant along direction D1 of the nanostructured first surface 112 or along an orthogonal direction D2.

[0056] In some embodiments, each of the nanostructured first surface of the first layer and the nanostructured first surface of the second layer includes a line with nano-features, wherein the nano-featured line of the first layer and the nano-featured line of the second layer intersect at an angle of 80 to 100 degrees. For example, referring to FIG11A, a top view of an exemplary article is provided, wherein two nano-featured lines intersect each other. More specifically, article 11000 shows: a first surface 1010 of a first layer, which includes a line 1100 with nano-features; and a first surface 1020 of a second layer (below the first surface 1010), which includes a line 1200 with nano-features. The linear nanostructures 1100 and 1200 are directly joined, wherein the linear directions of the two surfaces are azimuthally rotated such that the linear directions are approximately 90 degrees, thereby forming an "X" pattern when viewed from the top or bottom of one of the autonomous surfaces. Figure 11B provides a cross-sectional SEM image of a portion of an exemplary article 1100 of Example 6. Article 1100 includes a first surface 1010 of a first layer, a first surface 1020 of a second layer, and the intersection of linear nano features 1100 and 1200.

[0057] In any embodiment, any one or more of these layers have an average thickness greater than 50 nm, such as 100 nm or greater, 200 nm or greater, 300 nm or greater, 400 nm or greater, 500 nm or greater, 700 nm or greater, 900 nm or greater, 1 μm or greater, 1.25 μm or greater, 1.5 μm or greater, 1.75 μm or greater, 2 μm or greater, 2.25 μm or greater, 2.5 μm or greater, 2.75 μm or greater, or 3 μm or greater; and an average thickness of 1 mm or less, 0.75 mm or less, 0.5 mm or less, 0.25 mm or less, 0.1 mm or less, 0.05 mm or less, or 0.01 mm or less. In an alternative embodiment, any one of these layers (e.g., the second layer) is non-porous.

[0058] In some embodiments, any one or more layers (e.g., a planar layer in contact with a nanostructured surface) comprise a polymeric film. The polymeric "film" is a polymeric material in the form of a generally flat sheet, possessing sufficient flexibility and strength to be processed in a roll-to-roll manner. The polymeric film used in the articles described herein is sometimes referred to as a base film. Roll-to-roll refers to a process of winding or unwinding material onto or from a support and further processing it in some manner. Examples of further processing include coating, cutting, blanking, and exposure to radiation, or similar methods. Polymeric films can be manufactured in various thicknesses, typically ranging from about 5 micrometers to 1000 micrometers. Similarly, any one or more nanostructured layers may comprise a generally flat film other than a nanostructured surface.

[0059] Referring to Figures 4 through 7, suitable fifth to twelfth layers comprise inorganic and organic materials; for example, they comprise a polymeric layer. Any or more of the fifth to twelfth layers may be referred to as a substrate. Suitable materials for a polymeric substrate include copolyester polymers such as polyethylene terephthalate (PET) and glycol-modified polyethylene terephthalate (PETg), cyclo-olefin polymers (COP), cyclo-olefin copolymers (COC), poly(ethylenenaphthalate), PEN, polycarbonate (PC), acrylate polymers such as alicyclic acrylates or poly(methyl methacrylate), PMMA, polyimide (PI), polyurethane, and cast cellulose diacetate, and mixtures or copolymers comprising these materials. There is no particular limitation on the thickness of the substrate, and it can range from 5 micrometers to 1 centimeter, 10 micrometers to 500 millimeters, or 50 micrometers to 250 millimeters. In other words, the polymer substrate can have a thickness of 5 micrometers or more, 7 micrometers or more, 10 micrometers or more, 20 micrometers or more, 35 micrometers or more, 50 micrometers or more, 75 micrometers or more, 100 micrometers or more, 250 micrometers or more, 500 micrometers or more, 750 micrometers or more, or 1 millimeter or more; and a thickness of 1 centimeter or less, 9 millimeters or less, 8 millimeters or less, 7 millimeters or less, 6 millimeters or less, 5 millimeters or less, 3.5 millimeters or less, 2.5 millimeters or less, 1 millimeter or less, 0.50 millimeters or less, 0.25 millimeters or less, or 0.10 millimeters or less. In addition, additional suitable substrates may include painted or graphic-printed substrates, including metals, plastics, and glass.

[0060] Optionally, in any article according to this disclosure, any included substantially planar layer comprises a low birefringence layer. "Low birefringence" means a layer having a retardation of 25 nm or less. Suitable materials for the low birefringence layer include, for example, polyurethane, acrylate polymers such as polymethyl methacrylate and alicyclic acrylates, polycarbonate polymers, cyclic olefin polymers and copolymers, copolyester polymers (e.g., PETg), and cast cellulose diacetate.

[0061] Preferably, the article is transparent to visible light. The advantage of making the article transparent to visible light is that it is suitable for many applications, such as optical information displays and OLED devices.

[0062] Referring to Figures 1-2 and Figures 4-7, examples of suitable materials for any one or more of the first, second, third, or fourth layers include the following: high-refractive-index organic materials; polymeric materials filled with nanoparticles; polymers filled with high-refractive-index inorganic materials; and high-refractive-index conjugated polymers. Examples of high-refractive-index polymers and monomers are described in the following documents: C. Yang et al., Chem. Mater. 7, 1276 (1995), and R. Burzynski et al., Polymer 31, 627 (1990), and U.S. Patent No. 6,005,137, all of which are incorporated herein by reference to the extent that they do not conflict with this specification. Examples of polymers filled with high-refractive-index inorganic materials are described in U.S. Patent No. 6,329,058. Examples of nanoparticles used for polymeric materials filled with nanoparticles include the following high-refractive-index materials: TiO2, ZrO2, HfO2, or other inorganic materials. In some embodiments, suitable materials for any one or more of the first to fourth layers include low-refractive-index materials, such as those described in U.S. Patent No. 8,012,567 (Gaides et al.); or ultra-low-refractive-index materials, such as those described in U.S. Patent Application Publication No. 2012 / 0038990 (Hao et al.). In alternative embodiments, any one or more of the first to fourth layers comprises an acrylic polymer or copolymer, such as at least one polymerizable component selected from (meth)acrylate monomers, (meth)acrylate oligomers, and mixtures thereof. As used herein, "monomer" or "oligomer" means any substance that can be converted into a polymer. The term "(meth)acrylate" refers to both acrylates and methacrylate compounds. In alternative embodiments, the first and second layers, and / or the third and fourth layers, comprise the same materials.

[0063] In some embodiments, the polymerizable composition for forming any one or more of the first to fourth layers comprises (e.g., only) a crosslinking agent as a (meth)acrylate monomer comprising at least three (meth)acrylate functional groups. In some embodiments, the crosslinking monomer comprises at least four, five, or six (meth)acrylate functional groups. Acrylate functional groups are preferred over (meth)acrylate functional groups. Preferred commercially available crosslinking agents include, for example, trimethylolpropane triacrylate (available under the trademark "SR351" from Sartomer Company, Exton, PA), ethoxylated trimethylolpropane triacrylate (available under the trademark "SR454" from Sartomer Company), pentaerythritol tetraacrylate, pentaerythritol triacrylate (available under the trademark "SR444" from Sartomer Company), dipentaerythritol pentaacrylate (available under the trademark "SR399" from Sartomer Company), ethoxylated pentaerythritol tetraacrylate, ethoxylated pentaerythritol triacrylate (available under the trademark "SR494" from Sartomer), dipentaerythritol hexaacrylate, and tris(2-hydroxyethyl) isocyanurate triacrylate (available under the trademark "SR368" from Sartomer).

[0064] Useful poly(meth)acrylate monomers and oligomers include: (a) Monomers containing di(meth)acrylic acid, such as 1,3-butanediol diacrylate, 1,4-butanediol diacrylate, 1,6-hexanediol diacrylate, 1,6-hexanediol monoacrylate monomethacrylate, ethylene glycol diacrylate, alkoxylated aliphatic diacrylate, alkoxylated cyclohexanediethanol diacrylate, alkoxylated hexanediol diacrylate, alkoxylated neopentyl glycol diacrylate, neopentyl glycol hydroxytrimethyl acetate diacrylate modified with caprolactone, etc. Lactone-modified neopentyl glycol hydroxytrimethyl acetate diacrylate, cyclohexanediol diacrylate, diethylene glycol diacrylate, dipropylene glycol diacrylate, ethoxylated bisphenol A diacrylate, trimethylolpropane diacrylate modified with trimethylolacetaldehyde, neopentyl glycol diacrylate, polyethylene glycol diacrylate, propoxylated neopentyl glycol diacrylate, tetraethylene glycol diacrylate, tricyclodecanediol diacrylate, triethylene glycol diacrylate, and tripropylene glycol diacrylate; (b) Monomers containing a tri(meth)acrylic acid group, such as glyceryl triacrylate, trimethylolpropane triacrylate, ethoxylated triacrylate (e.g., ethoxylated trimethylolpropane triacrylate), propoxylated triacrylate (e.g., propoxylated glyceryl triacrylate, propoxylated trimethylolpropane triacrylate), trimethylolpropane triacrylate, and tris(2-hydroxyethyl)isocyanurate triacrylate; and (c) Monomers containing a higher functional (meth)acrylic group, such as di(trimethylolpropane)tetraacrylate, dipentaerythritol pentaacrylate, pentaerythritol triacrylate, ethoxylated pentaerythritol tetraacrylate, and dipentaerythritol hexaacrylate modified with caprolactone.

[0065] In one embodiment, a suitable polymerizable composition includes at least one monomer or oligo(meth)acrylate, preferably a carbamate (meth)acrylate. Generally, the monomer or oligo(meth)acrylate is a poly(meth)acrylate. The term "(meth)acrylate" is used to represent an ester of acrylic acid and methacrylic acid, and "multi(meth)acrylate" represents a molecule containing more than one (meth)acrylate group, as opposed to "poly(meth)acrylate," which typically represents a polymer of (meth)acrylate. Most commonly, poly(meth)acrylates are di(meth)acrylates, but tri(meth)acrylates, tetra(meth)acrylates, etc., are also contemplated. Suitable monomers or oligo(meth)acrylates include alkyl (meth)acrylates, such as methyl acrylate, ethyl acrylate, 1-propyl acrylate, methyl methacrylate, 2-phenoxyethyl acrylate, tetrahydrofurfuryl acrylate, and tributyl acrylate. Acrylates may include (fluoro)alkyl ester monomers of (meth)acrylic acid, which are partially or fully fluorinated, such as trifluoroethyl (meth)acrylic acid.

[0066] Examples of commercially available poly(meth)acrylate resins include the DIABEAM series from Mitsubishi Rayon Co.,LTD.; the DINACOL series from Nagase & Company,Ltd.; the NK ESTER series from Shin-Nakamura Chemical Co.,Ltd.; the UNIDIC series from Dainippon Ink & Chemicals,Inc.; the ARONIX series from Toagosei Co.,LTD.; the BLENMER series manufactured by NOF Corp.; the KAYARAD series from Nippon Kayaku Co.,Ltd.; and the LIGHT ESTER and LIGHT ACRYLATE series from Kyoeisha Chemical Co.,Ltd.

[0067] Oligomeric poly(meth)acrylates are commercially available, for example, under the trade name "Photomer 6000 Series," such as "Photomer 6010" and "Photomer 6210," from IGM Resins, and also under the trade name "CN 900 Series," such as "CN966B85," "CN964," and "CN972," from Sartomer Company. Oligomeric poly(meth)acrylates are also available from Surface Specialties, such as under the trade names "Ebecryl 8402," "Ebecryl 8807," and "Ebecryl 4827." Oligomeric poly(meth)acrylates can also be prepared by the initial reaction of an alkyl or aromatic diisocyanate of the formula OCN-R3-NCO with a polyol. The most commonly used are diols of the polyol form HO-R4-OH, wherein R3 is a C2-100 alkyl or aryl group, and R4 is a C2-100 alkyl group. The alkyl and aryl groups may include ether or ester groups. The intermediate product is then a carbamate diol diisocyanate, which may subsequently undergo a reaction with hydroxyalkyl (meth)acrylate. Suitable diisocyanates include 2,2,4-trimethylhexyl diisocyanate and toluene diisocyanate. Alkyl diisocyanates are generally preferred. Particularly preferred compounds of this type can be prepared from hexane diisocyanate, poly(caprolactone) diol, and 2-hydroxyethyl methacrylate. In at least some cases, carbamate (meth)acrylates are preferably aliphatic.

[0068] The polymerizable composition may be a mixture of various monomers and / or oligomers having the same or different reactive functional groups. Polymerizable compositions containing two or more different functional groups may be used, including (meth)acrylates, epoxy resins, and carbamates. Different functionalities may be contained in different monomers and / or oligomeric moieties or in the same monomer and / or oligomeric moieties. For example, the resin composition may include acrylic or carbamate resins having epoxy and / or hydroxyl groups in the side chain, compounds having amino groups, and optionally silane compounds having epoxy or amino groups in the molecule.

[0069] Contributions can be polymerized using conventional techniques such as thermosetting, photopolymerization (by photochemical radiation), and / or electron beam curing. In one embodiment, the composition can be photopolymerized by exposing it to ultraviolet (UV) and / or visible light. More typically, photopolymerizable compositions are cured using photochemical radiation, such as UV radiation, electron beam radiation, visible light radiation, or any combination thereof. Skilled practitioners can select appropriate radiation sources and wavelength ranges for specific applications without extensive experimentation.

[0070] Curing agents and / or catalysts are known to be used in polymerizable compositions and are selected based on the (multiple) functional groups in the composition. If multiple curing functionalities are used, multiple curing agents and / or catalysts may be required. Combinations of one or more curing techniques (such as thermosetting, photocuring, and electron beam curing) are within the scope of this disclosure.

[0071] Furthermore, the polymerizable composition may contain at least one other monomer and / or oligomer (i.e., not as described above, i.e., monomers or oligo(meth)acrylates and oligourethane (meth)acrylates). This other monomer may reduce viscosity and / or improve thermomechanical properties and / or increase refractive index. Monomers possessing these properties include acrylic monomers (i.e., acrylates and methacrylates, acrylamide, and methacrylamide), styrene monomers, and vinyl-based unsaturated nitrogen heterocycles.

[0072] This also includes (meth)acrylates with other functionalities. Compounds of this type are illustrated by the following: 2-(N-butylaminomethyl)ethyl (meth)acrylate, 2,4-dichlorophenyl acrylate, 2,4,6-tribromophenyl acrylate, tribromophenoxyethyl acrylate, tributylphenyl acrylate, phenyl acrylate, phenyl thioacrylate, phenyl thioethyl acrylate, alkoxylated phenyl acrylate, isoborneol acrylate, and phenoxyethyl acrylate. The reaction product of tetrabromobisphenol A diepoxide and (meth)acrylic acid is also suitable. Other monomers may also be N-substituted or N,N-disubstituted (meth)acrylamide monomers, especially acrylamides. These include N-alkylacrylamides and N,N-dialkylacrylamides, especially those containing C1-4 alkyl groups. Examples include N-isopropylacrylamide, N-tert-butylacrylamide, N,N-dimethylacrylamide, and N,N-diethylacrylamide. The term "(meth)acrylamide" refers to acrylamide and methacrylamide.

[0073] Styrene compounds suitable as other monomers include styrene, dichlorostyrene, 2,4,6-trichlorostyrene, 2,4,6-tribromostyrene, 4-methylstyrene, and 4-phenoxystyrene. Ethylene-based unsaturated nitrogen heterocycles include N-vinylpyrrolidone and vinylpyridine.

[0074] Photopolymerizable compositions disclosed herein generally include at least one photoinitiator. Suitable exemplary photoinitiators are those available under the brand name OMNIRAD from IGM Resins (Waalwijk, The Netherlands), including 1-hydroxycyclohexylphenyl ketone (OMNIRAD 184), 2,2-dimethoxy-1,2-diphenylethyl-1-one (OMNIRAD 651), bis(2,4,6-trimethylbenzoyl)phenylphosphine oxide (OMNIRAD 819), 1-[4-(2-hydroxyethoxy)phenyl]-2-hydroxy-2-methyl-1-prop-1-one (OMNIRAD 2959), 2-benzyl-2-dimethylamino-1-(4-morpholinylphenyl)butanone (OMNIRAD 369), and 2-dimethylamino-2-(4-methyl-benzyl)-1-(4-morpholin-4-yl-phenyl)-but-1-one (OMNIRAD 184). 379), 2-methyl-1-[4-(methylthio)phenyl]-2-morpholinylprop-1-one (OMNIRAD 907), oligo[2-hydroxy-2-methyl-1-[4-(1-methylvinyl)phenyl]acetone]ESACURE ONE (Lamberti SpA, Gallarate, Italy), 2-hydroxy-2-methyl-1-phenylprop-1-one (DAROCUR 1173), 2,4,6-trimethylbenzoyldiphenylphosphine oxide (OMNIRAD TPO), and 2,4,6-trimethylbenzoylphenylphosphite (OMNIRAD TPO-L). Additional suitable photoinitiators include, for example, but not limited to, benzyl dimethyl ketal, 2-methyl-2-hydroxyacetone, benzoin methyl ether, benzoin isopropyl ether, anisolein methyl ether, aromatic sulfonylurea chlorides, photoactive oximes, and combinations thereof.

[0075] In some embodiments, a cationic photoinitiator is present in a composition comprising, for example, an epoxy resin component. Additionally, a thermal initiator may optionally be present in the photopolymerizable composition described herein. For example, radical photoinitiators, cationic photoinitiators, thermophotoinitiators, or any combination thereof may be present in the photopolymerizable composition.

[0076] Suitable cationic photoinitiators include, for example, but not limited to, bis[4-diphenylsmethylene]sulfide bis(hexafluoroantimonate); thiophenoxyphenylsmethylene antimonate (available from Chitec (Houston, Tx)), tris(4-(4-acetylatedphenyl)phenylthio)smethylene(pentafluorophenyl)borate, tris(4-(4-acetylatedphenyl)phenylthio)smethylene[(trifluoromethyl)sulfonylated]methyl, and tris(4-(4-acetylatedphenyl)phenylthio)smethylene hexafluorophosphate, [4-(1-methylethyl)phenyl](4-methylphenyl) 4-[4-(2-chlorobenzoyl)phenylthio]phenylbis(4-fluorophenyl)spar hexafluoroantimonate, and aromatic spar salts having an anion of (PF6-m(CnF2n+1)m)-, wherein m is an integer from 1 to 5 and n is an integer from 1 to 4 (available from CPI-200K or CPI-200S (which are spar salts from San-Apro Ltd., (Kyoto, JP)), available from San-Apro Ltd.'s TK-1, or available from San-Apro Ltd.'s HS-1).

[0077] In some embodiments, the photoinitiator is present in the photopolymerizable composition in an amount of up to about 5% by weight, based on the total weight of the polymerizable components in the photopolymerizable composition (e.g., excluding components such as particles). In some cases, the photoinitiator is present in an amount of about 0.1 to 5% by weight, 0.2 to 5% by weight, or 0.5 to 5% by weight, based on the total weight of the photopolymerizable composition.

[0078] In some embodiments, the thermal initiator is present in the polymerizable composition in an amount of up to about 5% by weight, such as about 0.1 to 5% by weight, based on the total weight of the polymerizable components in the polymerizable composition. Suitable thermal initiators include, for example, but not limited to, peroxides (such as benzoyl peroxide, dibenzoyl peroxide, dilauryl peroxide, cyclohexane peroxide, methyl ethyl ketone peroxide), hydroperoxides (e.g., tert-butyl hydroperoxide, and cumene hydroperoxide), dicyclohexyl peroxydicarbonate, 2,2'-azobis(isobutyronitrile), and tert-butyl perbenzoate. Examples of commercially available thermal initiators include initiators available under the VAZO brand from DuPont Specialty Chemical (Wilmington, DE), including VAZO 67 (2,2'-azobis(2-methylbutyronitrile)), VAZO 64 (2,2'-azobis(isobutyronitrile)), and VAZO 52 (2,2'-azobis(2,2-dimethylpentanonitrile)), and LUCIDOL 70 from Elf Atochem North America, Philadelphia, PA.

[0079] When more than one initiator (e.g., multiple photoinitiators and / or multiple thermal initiators) is used in a polymerizable composition to form a layer, the resulting layer generally contains some residual amounts of both a first initiator or initiator fragment and a second initiator or initiator fragment present in the layer.

[0080] Surprisingly, in some embodiments, the adhesion strength of the first and second, and / or third and fourth layers of the article can be sufficient to exhibit a peel force of 10 g / cm or greater, 20 g / cm or greater, 30 g / cm or greater, 40 g / cm or greater, or even 50 g / cm or greater. In some embodiments, at least one of the first to fourth layers fails on its own rather than the two layers separating from each other. Layer failure, as opposed to maintaining its structural integrity, means that the layer cracks, breaks, or fragments. Peel force (or layer failure) can be determined using a peel force test method: a 180-degree peel test can be performed using a slip / peel tester (trademarked "IMASS SP-2100" from iMass, Inc., Accord, MA) to evaluate the peel force. The test sample is cut into strips 2.54 cm wide. A test sample was mounted onto the SP-2100 platform by attaching one side of the laminate to the platform using 1-inch (2.54 cm) wide double-sided tape (e.g., 3M REPOSITIONABLE TAPE 665, available from 3M Co., St. Paul, MN). The laminate was then separated at the desired interface, and the portion of the laminate opposite the platform was attached to the iMass load cell. The platform was advanced at 0.508 cm / s, and the force was recorded for 10 seconds. The average peel force during this time was reported.

[0081] In a second embodiment, an optical information display is provided. The optical information display includes an article according to the first embodiment described in detail above. Referring to FIG3A, a schematic cross-sectional view of an exemplary article 300 is provided, wherein layer 320 is an article including at least one void, as described in detail above with respect to the first embodiment. Layer 310 may represent at least one layer in an optical information display. Some examples of information displays include, for example, but not limited to, LCD TVs, computer monitors, mobile phone displays, OLED phones or TVs, smartwatches, inorganic LED displays, and the like.

[0082] In a third embodiment, an OLED device is provided. This OLED device includes an article according to the first embodiment described in detail above. The organic light-emitting diode (OLED) device includes at least one thin film of electroluminescent organic material sandwiched between a cathode and an anode, wherein one or both of these electrodes are capable of transmitting light. When a voltage is applied across the device, electrons and holes are injected from their respective electrodes and recombine in the electroluminescent organic material through intermediate exciton formations.

[0083] Once appropriate values ​​for the design parameters have been identified, OLED display panels can be fabricated using conventional OLED manufacturing processes that may include depositing organic layers by one or more of vacuum deposition, vacuum thermal evaporation, organic vapor deposition, and inkjet printing. Useful methods for manufacturing OLED display panels are described in U.S. Patent Application Publication Nos. 2010 / 0055810 (Sung et al.), 2007 / 0236134 (Ho et al.), 2005 / 0179373 (Kim), and 2010 / 0193790 (Yeo et al.).

[0084] An OLED display typically includes a pixel array, and each pixel may include several subpixels. Generally, each OLED subpixel emits red, blue, or green light. In some cases, subpixels emitting white, cyan, magenta, yellow, or other colors of light may be used. An OLED subpixel includes at least one, and often several, layers of organic material sandwiched between a cathode and an anode. The design of an OLED subpixel involves selecting the thickness and optical and electronic properties of each layer so that the emitted light has the desired output. Sometimes the OLED layer architecture is referred to as an "emission stack" or an OLED "stack".

[0085] Referring to FIG3B, a schematic cross-sectional view of an OLED structure according to one of the examples below is provided. An article according to the first example may be incorporated into an OLED structure, for example, for the purpose of reducing OLED color shift. Thus, article layer 320 may be incorporated into OLED portions 312 and 314. As described in U.S. Provisional Patent Applications No. 62 / 342620 (Freier et al.), No. 62 / 414127 (Erickson et al.), and PCT Publication No. WO 2017 / 205174 (Freier et al.), a color correction component (such as an optical stack including a nanostructured interface) may be placed adjacent to an emitting layer of an OLED display panel to reduce color variation with viewing direction without substantially altering the positive axial light output of the display. Other practical color correction components include partial reflectors, which, for example, provide wavelength-dependent reflectivity and transmissivity. Useful partial reflectors are described, for example, in U.S. Provisional Patent Applications No. 62 / 566654 (Haag et al.), No. 62 / 383058 (Benoit et al.), and No. 62 / 427450 (Benoit). Other useful color correction components include polymeric films, which function, for example, as moderate optical diffusers. Useful polymeric films are described, for example, in U.S. Patent Applications No. 15 / 587929 (Hao et al.) and No. 15 / 587984 (Hao et al.). In some embodiments, an OLED display includes an encapsulation material that may include one or more layers of adjacent or adjacent emission stacks. Optionally, the emission stack may contain one or more layers disposed between a cathode and the encapsulation material. A circular polarizer may be disposed adjacent to the encapsulation material. In some cases, a touch sensor may be included in the OLED display. The touch sensor may optionally be included between the encapsulation material and the circular polarizer. The article in the first state can be positioned between the encapsulation material and the viewer; the article in the first state can optionally be positioned between the encapsulation material and the circular polarizer or between the encapsulation material and the touch sensor.

[0086] In some embodiments, the color correction component may be placed adjacent to the top surface of a top-emitting OLED or adjacent to the bottom surface of a bottom-emitting OLED. For example, referring again to FIG3A, an article layer 320 containing at least one void may be disposed adjacent to the emitting surface of an OLED 310. The OLED may be a strong-cavity OLED, a weak-cavity OLED, or a cavityless OLED. The current mainstream OLED market is active-matrix organic light-emitting diode (AMOLED) displays, which have a top-emitting architecture and currently do not use any light extraction methods, except for those employing a strong microcavity design. This strong-cavity design can have high axial efficiency, but when compared with, for example, liquid crystal displays (LCDs), the angular color uniformity relative to the viewing angle is worse. In some embodiments of this specification, the color correction component is advantageously used with strong-cavity OLEDs (such as AMOLEDs) because relatively large color shifts are generally present in strong-cavity OLEDs. In some embodiments, an OLED display includes: an encapsulation material disposed on the emitting layer; and a circular polarizer disposed adjacent to the encapsulation material. In some embodiments, the color correction component is disposed between the encapsulation material and the circular polarizer. method

[0087] Various methods can be employed according to this disclosure to prepare articles according to the first state described above. A suitable method for manufacturing an article includes: obtaining a first material comprising a nanostructured first surface including a nano-feature and an opposing second surface; contacting a second layer with a portion of the nano-feature, the second layer comprising a first flat or nanostructured surface; and reacting at least one of the first material or the second material to fix the first layer and the second layer together. The nano-feature of the first layer and the first flat or nanostructured surface of the second layer together define at least one void. In any embodiment, the first layer is contacted with the second layer by laminating the first layer and the second layer together. Lamination of layers is well known and often involves processes such as subjecting at least one outer main surface of a stacked layer to a weighted roller, or passing the stacked layers through a nip roller line or a benchtop laminator. Examples provide additional details regarding the preparation of articles according to this disclosure.

[0088] In embodiments that include any additional layer (e.g., a fifth layer, a sixth layer, etc.) attached to any of the main surfaces of the first to fourth layers, the additional layers are preferably attached to one of the first to fourth layers respectively before the first layer contacts the second layer, or the third layer contacts the fourth layer. For example, a second surface opposite to one of the first layers may be attached to a substrate (e.g., a layer) and / or the second layer may have a second main surface attached to a substrate (e.g., a layer).

[0089] In any embodiment, the first and / or second materials are reacted by subjecting the first and / or second layers to photochemical radiation. Generally, photochemical radiation includes ultraviolet (UV) light, visible light, electron beams, or any combination thereof. Alternatively or otherwise, the first and / or second materials are reacted by subjecting the first and / or second layers to heating. An advantage of reacting one or more of the first or second materials is that the reaction typically establishes a stronger bond between the first and second layers than that achieved solely by applying physical pressure (e.g., lamination) to the main surfaces outside the first and second layers, particularly because the main surface of the second layer generally only contacts a portion of the nanofeatures rather than the entire main surface of the first layer. For example, reacting a crosslinkable material can create crosslinks between the first and second layers. In some embodiments, at least one of the first or second layers comprises a partially cured material, and the partially cured material is reacted to bond the first and second layers together. Optionally, the first and / or second layers comprise a photoinitiator, a thermal initiator, or both.

[0090] In some embodiments, the second layer comprises a resin having a solids content of 90% or greater, 92% or greater, 94% or greater, 95% or greater, 96% or greater, 98% or greater, or 99% or greater. Components considered "solids" include, for example, but not limited to, polymers, oligomers, monomers, and additives such as initiators and fillers. Generally, only solvents do not fall within the definition of solids, such as water or organic solvents. In a preferred embodiment, the second layer contains less than 5% by weight of total solvent content, preferably less than 1% by weight of total solvent content. In some embodiments, the polymeric material is solvent-free except for any residual solvent (e.g., less than 0.5% by weight of the second layer).

[0091] In embodiments where the first material is an inorganic material, the method may optionally include reacting a second material to fix the first and second layers together. The second material may react with a functionalized inorganic material. For example, a coupling agent may be bonded to the inorganic material of the first layer, specifically to the nanostructured first surface of the first layer.

[0092] Generally, coupling agents comprise at least one group bonded to an organic layer (covalent or non-covalent) and at least one group bonded to an inorganic layer (covalent or non-covalent). Covalent bonding requires a surface reaction between the group and the surface it contacts. For example, consider the coupling agent 2-(3-trimethoxysilylpropylaminomethoxy)ethylprop-2-enoate (K90) having the following structure: The acrylate group can react with other acrylates in the adjacent organic layer to form an acrylate copolymer. Other functional groups that can be covalently or non-covalently bonded to the (meth)acrylate coating may include (meth)acrylate, vinyl, amine, carbamate, urea, and thiol functional groups. Similarly, the trimethoxysilyl group can react (e.g., once, twice, or three times) with one or more metal M (e.g., silicon, aluminum) hydroxide groups in the adjacent inorganic layer to form a -Si-OM- bond. Other groups (e.g., acid groups, such as carboxylic acids, sulfonic acids, phosphonic acids, or phosphate groups) can form non-covalent bonds via hydrogen bonding in portions of the organic or inorganic layer adjacent to the coupling agent. The coupling agent is a distinct compound before bonding to at least one surface, and can be referred to as a "bonded coupling agent" after bonding to at least one surface. Therefore, any inorganic atom (such as silicon, phosphorus, titanium, or zirconium) can still be part of a bonded coupling agent. When such inorganic atoms are not identical to the metal M, their presence can be detected by analytical methods in some embodiments.

[0093] Suitable coupling agents include, for example, but not limited to, functionalized silanes having hydrolyzable alkoxy or chlorinated groups bonded to silicon atoms, with (meth)acrylate silane coupling agents being particularly useful. Such coupling agents are commercially available from Momentive, Gelest, Evonik, Shin-Etsu, and others. Suitable silane materials may include functional groups (covalently or non-covalently) bonded to the (meth)acrylate coating, including (meth)acrylate, vinyl, amine, carbamate, urea, and thiol functional groups. Suitable materials may include: functional groups (covalently or non-covalently) bonded to the inorganic layer, such as hydrolyzable silyl groups, acids (including phosphoric acid, phosphonic acid, sulfonic acid, and carboxylic acid groups); and other groups, such as phenols, polyphenols, amines, alcohols, and thiols. This includes 2-(3-trimethoxysilylpropylaminomethoxy)ethylprop-2-enoate, a silane acrylate coupling agent, and others given below: U.S. Patent No. 7,799,888 (Arkles et al.); No. 9,029,586 (Arkles et al.); No. 9,254,506 (Roehrig et al.); No. 9,790,396 (Klun et al.); No. 9,982,160 (Klun et al.); No. 10,011,735 (Klun et al.); and U.S. Patent Application Publication No. 2015 / 0203707 (Klun et al.) and No. 2015 / 0218294 (Klun et al.). In addition, suitable coupling agents having phosphonic acid groups include those given in U.S. Patent Application Publication No. 2020 / 0017623 (Ye et al.) and International Application Publication No. WO 2020 / 046654 (Lin et al.).

[0094] Coupling agents are often first covalently or non-covalently bonded to a layer, followed by bonding at least one of the coupling agents in the first layer or the second layer, to bond the first and second layers together through the bonding coupling agent. Alternatively, a bonded coupling agent can be formed when the coupling agent is bonded to one of the first or second layers and also to another present coupling agent compound or other photoreactive component (e.g., monomer, oligomer, or polymer). This is more likely to occur when the coupling agent is present as a portion of a coupling agent layer, the thickness of which is at least the length (or greater) of the coupling agent compound.

[0095] Optionally, the bonded coupling agent comprises at least one of silicon, phosphorus, titanium, or zirconium. In some embodiments, the bonded coupling agent comprises at least one functional group selected from the following: acrylate, carbamate, urea, alkylene, urea group, isocyanate, epoxy group, alcohol, amine, thiol, phenol, amino group, acid, heteroatom, and at least one of silicon, phosphorus, titanium, or zirconium.

[0096] When the first surface of the nanostructured first layer contains protruding nanofeatures, a bonding coupling agent is used to bond to a portion of these protruding nanofeatures. When the nanofeatures of the first surface of the nanostructured first layer are all grooved nanofeatures, they are used to bond to a portion of the main surface of the first layer via a bonding coupling agent. In some embodiments, a portion of the first surface of a second nanostructured layer is covalently bonded to a portion of the first surface of the nanostructured first layer via a bonding coupling agent. Figure 12B is an SEM image showing a cross-section of a portion of the exemplary article 12000 of Example 7 below, wherein the material of the first layer 110 is silicon dioxide, and the material of the second layer 120 comprises a polymeric material. The first layer 110 includes grooved nanofeatures 114, and the second layer 120 includes grooved nanofeatures 124, and these layers are attached together, defining a plurality of voids 130 between the nanostructured surfaces of the first layer 110 and the nanostructured surfaces of the second layer 120. Some voids are located between opposing grooved nanofeatures of the first and second layers (e.g., as shown in FIG. 12B), while some voids are located between a grooved nanofeature of one layer and the surface of the other layer.

[0097] As used herein, the term "residue" is used to define the portion of the coupling agent remaining after the removal of groups that can form bonds (covalent or non-covalent) in the first and second layers. Generally, covalent bonds are stronger than non-covalent bonds. As mentioned above, the coupling agent becomes a residue only when both end groups are removed during the reaction. For example, the "residue" of the coupling agent 2-(3-trimethoxysilylpropylaminomethoxy)ethylprop-2-enoate (K90) is shown below: Department -CH2CH2OC(O)NHCH2CH2-CH2-.

[0098] Another exemplary coupling agent system

[0099] The residue of this coupling agent is -CH2CH2OC(O)CH2CH2-.

[0100] In some cases, such as targeting The coupling agent residues are covalently bonded.

[0101] The residues of the coupling agent are the "core" of the coupling agent remaining after the terminal functional group reacts with the first and second layers.

[0102] In some embodiments, the first master surface of the second layer is directly bonded to the nanostructured first surface of the first layer via a bonding coupling agent. In such embodiments, at least one closed void is defined by the nanostructured first surface of the first layer and the first master surface of the second layer. Selected embodiments disclosed herein

[0103] In a first embodiment, this disclosure provides an article. The article comprises a) a first layer comprising a nanostructured first surface including one of nano-features and an opposing second surface, wherein the nanostructured first surface includes a groove-like feature, or a protruding feature, or both groove-like and protruding features formed of a single component; and b1) or b2). b1) is a second layer comprising a first main surface and an opposing second main surface, the first main surface being attached to a portion of the nano-features of the first layer, and the nanostructured first surface of the first layer and the first main surface of the second layer together define at least one first void. b2) is a third layer comprising a nanostructured first surface including one of nano-features and an opposing second surface, wherein a portion of the nano-features of the third layer is attached to a portion of the nano-features of the first layer, and the nanostructured first surface of the third layer and the nanostructured first surface of the first layer together define at least one second void. The article includes the following condition: when b1) is present, the article further includes c) a fourth layer, the fourth layer including a nanostructured first surface including a nano feature and an opposing second surface. The second surface of the fourth layer or the nanostructured first surface of the fourth layer is adjacent to the second main surface of the second layer or adjacent to the second surface of the first layer.

[0104] In a second embodiment, this disclosure provides an article according to a first embodiment, wherein b1) is present.

[0105] In a third embodiment, this disclosure provides an article according to a first or second embodiment, wherein b1) is present, and the article further comprises: d) a fifth layer comprising a first main surface and an opposing second main surface, wherein the first main surface is attached to a portion of the nano-features of the fourth layer. The nanostructured first surface of the fourth layer and the first main surface of the fifth layer together define at least a third void.

[0106] In a fourth embodiment, this disclosure provides an article according to a first embodiment, wherein b2) is present, and the article further comprises: e) a sixth layer comprising a nanostructured first surface including nano-features and an opposing second surface; and f) a seventh layer comprising a first main surface and an opposing second main surface, wherein the first main surface is attached to a portion of the nano-features of the sixth layer. The nanostructured first surface of the sixth layer and the first main surface of the seventh layer together define at least a fourth void. The second surface of the sixth layer or the second main surface of the seventh layer is adjacent to the second main surface of the second layer or adjacent to the second surface of the first layer.

[0107] In a fifth embodiment, this disclosure provides an article according to a first embodiment, wherein b2) is present, and the article further comprises: g) an eighth layer comprising a nanostructured first surface including a nano-feature and an opposing second surface; and h) a ninth layer comprising a nanostructured first surface including a nano-feature and an opposing second surface, wherein a portion of the nano-features of the ninth layer is attached to a portion of the nano-features of the eighth layer. The nanostructured first surface of the ninth layer and the nanostructured first surface of the eighth layer together define at least a fifth void. The second surface of the eighth layer or the second surface of the ninth layer is adjacent to the second surface of the third layer or adjacent to the second surface of the first layer.

[0108] In a sixth embodiment, this disclosure provides an article according to a first embodiment, wherein b1) exists, and the article further comprises: i) a tenth layer comprising a nanostructured first surface including nano-features and an opposing second surface; and j) an eleventh layer comprising a nanostructured first surface including nano-features and an opposing second surface, wherein a portion of the nano-features of the eleventh layer is attached to a portion of the nano-features of the tenth layer. The nanostructured first surface of the eleventh layer and the nanostructured first surface of the tenth layer together define at least a sixth void. The second surface of the tenth layer or the second surface of the eleventh layer is adjacent to the second main surface of the second layer or adjacent to the second surface of the first layer.

[0109] In a seventh embodiment, this disclosure provides an article according to any of the first to sixth embodiments, which further includes a twelfth layer disposed adjacent to the second main surface of the second layer or the second surface of the first layer.

[0110] In the eighth embodiment, this disclosure provides an article according to the seventh embodiment, wherein the twelfth layer is a low birefringence layer.

[0111] In a ninth embodiment, this disclosure provides an article according to any of the first to eighth embodiments, further comprising a thirteenth layer disposed adjacent to the second main surface of the second layer or the second surface of the first layer.

[0112] In the tenth embodiment, this disclosure provides an article according to the ninth embodiment, wherein the thirteenth layer comprises a crosslinked material or a crosslinkable material.

[0113] In the eleventh embodiment, this disclosure provides an article according to any one of the first to third or sixth to ninth embodiments, wherein the second layer is substantially flat.

[0114] In the twelfth embodiment, this disclosure provides an article according to any one of the first to eleventh embodiments, wherein at least one of the first to sixth cavities is present, and at least one of the first to sixth cavities contains gas.

[0115] In the thirteenth embodiment, this disclosure provides an article according to any one of the first to twelfth embodiments, wherein the first layer is an organic layer.

[0116] In the fourteenth embodiment, this disclosure provides an article according to any one of the first to thirteenth embodiments, wherein the first layer comprises a polymeric material.

[0117] In the fifteenth embodiment, this disclosure provides an article according to any one of the first to fourteenth embodiments, wherein the second layer or the third layer comprises a polymeric material.

[0118] In a sixteenth embodiment, this disclosure provides an article according to any one of the first to fifteenth embodiments, wherein the first layer and the second or third layer comprise the same material.

[0119] In the seventeenth embodiment, this disclosure provides an article according to any one of the first to sixteenth embodiments, wherein at least one of the first layer, the second layer, or the third layer comprises a crosslinked material or a crosslinkable material.

[0120] In the eighteenth embodiment, this disclosure provides an article according to any one of the first to seventeenth embodiments, wherein at least one of the first layer, the second layer, or the third layer comprises an acrylic polymer or copolymer.

[0121] In the nineteenth embodiment, this disclosure provides an article according to any one of the first to eighteenth embodiments, wherein at least one of the first layer, the sixth layer, the eighth layer, the ninth layer, the tenth layer, or the eleventh layer includes nano-features having a height of less than 1 micrometer.

[0122] In the twentieth embodiment, this disclosure provides an article according to any one of the first to nineteenth embodiments, wherein at least one of the first layer, the sixth layer, the eighth layer, the ninth layer, the tenth layer, or the eleventh layer includes nano-features having a width of less than 1 micrometer.

[0123] In the twenty-first embodiment, this disclosure provides an article according to any one of the first to twentieth embodiments, wherein at least one of the first layer, the sixth layer, the eighth layer, the ninth layer, the tenth layer, or the eleventh layer includes nano-features having at least one nonlinear surface in at least one direction.

[0124] In the twenty-second embodiment, this disclosure provides an article according to any one of the first to twenty-first embodiments, wherein at least one of the first layer, the sixth layer, the eighth layer, the ninth layer, the tenth layer, or the eleventh layer includes nanofeatures with groove-like features.

[0125] In the twenty-third embodiment, this disclosure provides an article according to any one of the first to twenty-second embodiments, wherein at least one of the second layer or the third layer has an average thickness greater than 50 nanometers, 100 nanometers, 500 nanometers, 1 micrometer, 2 micrometers, or 3 micrometers.

[0126] In the twenty-fourth embodiment, this disclosure provides an article according to any one of the first to twenty-third embodiments, wherein b1) is present and the second layer is non-porous.

[0127] In the twenty-fifth embodiment, this disclosure provides an article according to any one of the first to twenty-fourth embodiments, wherein the nanostructured first surface of the first layer has only groove-like features.

[0128] In the twenty-sixth embodiment, this disclosure provides an article according to any one of the first to twenty-fourth embodiments, wherein the nanostructured first surface of the first layer includes protruding features.

[0129] In the twenty-seventh embodiment, this disclosure provides an article according to any one of the first to twenty-fourth or twenty-sixth embodiments, wherein the nanostructured first surface of the first layer has only protruding features.

[0130] In the twenty-eighth embodiment, this disclosure provides an article according to any one of the first, fourth, fifth, seventh to tenth, twelfth to twenty-third, or twenty-fifth to twenty-seventh embodiments, wherein b2) is present and the nanostructured first surface of the third layer includes groove-like features.

[0131] In the twenty-ninth embodiment, this disclosure provides an article according to any one of the first, fourth, fifth, seventh to tenth, twelfth to twenty-third, or twenty-fifth to twenty-eighth embodiments, wherein b2) is present and the nanostructured first surface of the third layer has only groove-like features.

[0132] In the thirtieth embodiment, this disclosure provides an article according to any one of the first, fourth, fifth, seventh to tenth, twelfth to twenty-third, or twenty-fifth to twenty-eighth embodiments, wherein b2) is present and the nanostructured first surface of the third layer includes protruding features.

[0133] In the thirty-first embodiment, this disclosure provides an article according to any one of the first, fourth, fifth, seventh to tenth, twelfth to twenty-third, twenty-fifth to twenty-seventh, or thirtieth embodiments, wherein b2) is present and the nanostructured first surface of the third layer has only protruding features.

[0134] In the thirty-second embodiment, this disclosure provides an article according to any one of the first to thirty-first embodiments, which further includes a first initiator or initiator fragment and a second initiator or initiator fragment.

[0135] In the thirty-third embodiment, this disclosure provides an article according to any one of the first to thirty-second embodiments, wherein b2) exists, wherein each of the nanostructured first surface of the first layer and the nanostructured first surface of the third layer includes a line having nano-features, and wherein the nano-featured line of the first layer and the nano-featured line of the third layer intersect at an angle of 80 to 100 degrees.

[0136] In the thirty-fourth embodiment, this disclosure provides an article according to any one of the first, fourth, fifth, seventh to tenth, twelfth to twenty-third, or twenty-fifth to thirty-second embodiments, wherein the first layer is an inorganic layer.

[0137] In the thirty-fifth embodiment, this disclosure provides an article according to any one of the first to thirty-second embodiments, wherein the first layer comprises an oxide, a carbide, or a boride of metal or nonmetal, or a combination thereof.

[0138] In the thirty-sixth embodiment, this disclosure provides an article according to the thirty-fourth or thirty-fifth embodiment, wherein the first layer comprises silicon dioxide.

[0139] In the thirty-seventh embodiment, this disclosure provides an optical information display comprising an article according to any one of the first to thirty-sixth embodiments.

[0140] In the thirty-eighth embodiment, this disclosure provides an OLED device comprising an article according to any one of the first to thirty-sixth embodiments.

[0141] In the thirty-ninth embodiment, this disclosure provides an optical element comprising any of the articles in the thirty-fourth to thirty-sixth embodiments. Example

[0142] The advantages and embodiments of the present invention will be further illustrated by the following examples; however, the specific materials and amounts, as well as other conditions and details cited in these examples, should not be considered as unduly limiting the invention. Unless otherwise stated or apparent from the context, all parts, percentages, ratios, etc., in the examples and remainder of this specification are by weight. Materials used in the example Color calibration on OLED test pieces

[0143] The color shift reduction test of the blue light strong resonant cavity OLED is shown below. The OLED layer structure is summarized in Figure 3B.

[0144] In short, the layer structure is fabricated in the following order: a 15 nm thick indium tin oxide (ITO) layer, a 100 nm thick hole transport layer (HTL), a 10 nm thick electron blocking layer (EBL), a 20 nm thick emitter layer composed of 90% blue host material and 10% blue dopant material, a 50 nm thick electron transport layer, a 1.5 nm thick LiF layer, an 8 nm thick layer of 10% Ag and 90% Mg, and a 65 nm thick capping layer composed of the hole transport layer. All layers are deposited by vacuum thermal evaporation. A thin-film encapsulation is then applied, consisting of a 46 nm thick Al₂O₃ layer, a 2 μm thick UV-curable organic monomer (trademarked E-200 from EM Index Company, Daejeon, Korea) layer, and a 46 nm thick second Al₂O₃ layer. OLED devices are manufactured using various HTL thicknesses; each OLED device exhibits unique current efficiency (cd / A) and color shift. Color shift can be calculated from the CIE 1976 color coordinates (u', v'); the value of color shift is given as follows: △u'v'=SQRT((u'i-u'o)2+(v'i-v'o)2)), where (u'o, v'o) are the color coordinates emitted by the OLED at the normal viewing angle, and The (u'i, v'i) system, representing the overall color shift of a color coordinate system at an i-th viewing angle, is defined as the maximum color shift measured for viewing angles between 0 and 45 degrees. The color correction system is defined as the reduction in overall color shift between a reference OLED device and the same OLED device with a coated OLED. Just-noticeable-difference (JND) can be defined as a vector of length 0.005 in the CIE 1976 color space.

[0145] The brightness and color of each OLED device were measured using a calibrated spectrophotometer (brand name SPECTRASCAN PR-655, obtained from Photo Research, Inc., North Syracuse, NY) at normal incidence and viewing angles up to 60 degrees from normal incidence. The OLED devices were attached to a rotating base that allowed for repeated positioning at normal incidence and viewing angles up to 60 degrees from normal incidence. A nanostructured film was then applied to each OLED device using a refractive index matching gel (n=1.46). Measurements were then repeated for each OLED device with the nanostructured film. Color correction calculations were performed as described above. Color calibration of commercial OLED panels

[0146] The brightness and color of a commercial OLED LGv40 panel displaying a white image were measured using a calibrated spectrophotometer ("SPECTRASCAN PR-655") at normal incidence and at a 45-degree angle to normal incidence. The LGv40 panel was attached to a rotating base that allowed the device to be repeatedly positioned at normal incidence and at a 45-degree angle to normal incidence. A nanostructured film was then applied to the LGv40 panel using a refractive index matching gel (n=1.46), and the device was measured again in the same manner with the nanostructured film. Color correction calculations were performed as described above. SEM profile

[0147] Sectioned samples were prepared using a wide-beam ion mill (trademarked GATAN ILION III from Gatan, Inc., Pleasanton, California), or by immersing the sample in liquid nitrogen while simultaneously fracturing it. The sample was mounted to a blade mount using silver paint and an 80-micron protrusion around the blade edge, and subjected to an argon ion beam under vacuum to prepare the ion mill profile. The sample was inserted into the ion mill and cooled to -162°C, then milled at 5 kV while rotating at 1 revolution per minute (rpm). The sectioned sample was imaged using a scanning electron microscope. Preparation Example

[0148] The polyurethane acrylate mixture was prepared by first adding 540 g of HMDI to 1000 g of TERETHANE 1000, with 0.38 g of dibutyltin dilaurate as a catalyst. This isocyanate-terminated prepolymer was further reacted with 239.4 g of HEA (from Kowa) in the presence of 1.4 g of BHT and 0.1 g of MEHQ. The reaction was considered complete when the isocyanate peak was no longer present near 2275 cm⁻¹ according to Fourier transform infrared spectroscopy. The resulting polyurethane acrylate was then diluted with 1021 g of SR454.

[0149] Unless otherwise specified, after all components have been added, the resin composition is blended by heating to approximately 50°C and mixing on a roller mixer for 12 hours. The mixture appears homogeneous.

[0150] A mixture of polyurethane acrylate, SR602, SR601, SR351, and ETERMER 210 was combined and mixed in a weight ratio of 60 / 20 / 4 / 8 / 8 to produce resin A.

[0151] Resin B is prepared by adding and mixing IRGACURE TPO, DAROCUR 1173, and IRGANOX 1035 at a weight ratio of 0.35 / 0.1 / 0.2 parts per 100 parts of resin A.

[0152] Resin C is prepared by combining and mixing 0.5 parts by weight of ABP with 99.5 parts by weight of resin B.

[0153] Resin D is prepared by combining and mixing PHOTOMER 6210, SR238, SR351 and IRGACURE TPO in a weight ratio of 60 / 20 / 20 / 0.5.

[0154] Resin E is prepared by combining and mixing 0.5 parts by weight of AEBP with 99.5 parts by weight of resin B.

[0155] Mixture A was prepared by mixing 0.103 g of DAROCUR 1173 with 9.97 g of 2-propanol.

[0156] Mixture B was prepared by mixing 0.019 g K90, 0.062 g mixture A and 18.94 g 2-propanol.

[0157] Membrane A was prepared by first using a multilayer membrane prepared according to the method described in WO 2019 / 032635 A1 (Johnson et al.). The resulting multilayer membrane has a 43-micron polyethylene terephthalate (PET) layer, a 6-7 micron linear triblock copolymer ("KRATON G1645") layer, a 6-7 micron blend layer comprising 60 parts by weight of polypropylene ("PP9074MED") and 40 parts by weight of triblock copolymer ("KRATON G1645"), and a 15-micron copolyester ("EASTAR GN071") layer. Resin C was molded onto the copolyester surface of the multilayer membrane from a heated storage container through a heated hose and a heated mold (all set to 65.5°C). Using a rubber-coated roller, a coated film is pressed against a nanostructured nickel surface attached to a steel roller maintained at 71°C at a speed of 7.6 meters per minute (m / min). The coating thickness of resin C on the film is sufficient to completely wet the nanostructured nickel surface, and resin beads are formed as the coated film is pressed against the nanostructured nickel surface. The resin-coated film is exposed to radiation from a Phoseon UV LED curing system (trademarked "FIREJET FJ 300X20AC405-12W", obtained from Phoseon Technologies, Hillsboro, OR) while in contact with the nanostructured nickel surface, and the UV LED curing system is operated at 100% power. The nanostructured film A is then peeled off from the nanostructured nickel surface. The SEM image of the nanostructured surface of film A is shown in Figure 8.

[0158] Membrane B is prepared using the same procedure as membrane A, except that a smooth chromium surface is used instead of a nanostructured nickel surface, the copolyester layer is 5 micrometers thick, and the Phoseon UV LED curing system is operated at 75% power.

[0159] Membrane C is prepared by pressing the nanostructured surface of membrane A onto the resin-coated surface of membrane B at a speed of 6.1 m / min between a smooth chrome roller and a rubber-coated roller. While the membrane A side is still in contact with the smooth chrome roller, it is exposed to energy from a Fusion UV lamp system (trademarked "F600" from Fusion UV Systems, Gaithersburg, MD), equipped with a D bulb, operating at 236 W / cm. The membrane B side is then exposed to energy from the Fusion UV lamp system ("F600") after the membrane is removed from the smooth chrome roller, equipped with a D bulb, operating at 141 W / cm.

[0160] Membrane D was prepared using the same procedure as membrane A, but with a different nanostructured nickel surface. The SEM image of the nanostructured surface of membrane D is shown in Figure 9B. Membrane E

[0161] Membrane E is produced by coating a 125-micron-thick polycarbonate film (trademarked "LEXAN" from Tekra, Inc., New Berlin, WI) with a glossy finish on both sides, using resin E from a heated storage container via a heated hose and a heated mold (all set at 65.5°C). A rubber-coated roller presses the coated side of the film onto a nanostructured nickel mold attached to a steel roller maintained at 65°C. The resin E coating on the film is thick enough to completely wet the nickel surface, and when the coated film is pressed onto the nanostructured nickel surface, it forms rolled resin beads. The film is exposed to radiation from two Fusion UV lamp systems ("F600"), each equipped with a D bulb, operating at 142 and 236 W / cm, respectively, while in contact with the nanostructured mold surface. The resulting membrane E is then peeled off from the nanostructured mold surface. The SEM image of the nanostructured surface of membrane E is shown in Figure 10B. Membrane F

[0162] Membrane F was prepared using the following procedure. First, a nanostructured membrane was prepared using the procedure for producing membrane A, with the following variations: a nanostructured nickel surface with linear nanostructured characteristics was used; resin D was used instead of resin C; resin D was coated under ambient conditions; the steel roller was controlled at 65°C; and the resin-coated membrane was exposed to radiation from two Fusion UV lamp systems ("F600") equipped with D bulbs, operating at 142 W / cm. A thin coating was deposited on the resulting nanostructured membrane using plasma-enhanced chemical vapor deposition (PECVD) to create a nanostructured membrane mold. PECVD was performed in a built-in parallel-plate capacitively coupled plasma reactor. The chamber had a central cylindrical power supply electrode with a surface area of ​​18.3 ft². After placing the nanostructured membrane on the power supply electrode, the reactor chamber was pumped to a base pressure of less than 1.3 Pa (2 mTorr). Oxygen was introduced into the chamber at a flow rate of 1000 standard cubic centimeters per minute (SCCM). Treatment was performed by coupling RF power into the reactor at a frequency of 13.56 MHz and an applied power of 2000 W. The treatment time was controlled by moving the nanostructured membrane through the reaction zone at a rate of 30 ft / min. Oxygen flow was stopped, and HMDSO (hexamethyldisiloxane) was evaporated and transported into the system to maintain an operating pressure of approximately 9 mTorr, completing the second step of depositing a thin film on the nanostructured surface. Treatment was then performed using plasma-enhanced CVD with RF power coupled into the reactor at a frequency of 13.56 MHz and an applied power of 1000 W. The treatment time was controlled by moving the nanostructured membrane back through the reaction zone at a rate of 30 ft / min. After treatment, the RF power and gas supply were stopped, and the chamber was returned to atmospheric pressure. Additional information on the materials and procedures used to apply cylindrical PECVD, as well as further details regarding the reactor used, can be found in U.S. Patent No. 8,460,568 B2 (Moses et al.).

[0163] Next, the nanostructured membrane mold was adhered to a 1.6 mm thick aluminum plate (with the nanostructured side facing upwards), and a 75 μm thick biaxially oriented polyethylene terephthalate (PET) film (prepared internally) with an acrylic polymer ("RHOPLEX 3208", purchased from Dow, Midland, MI) adhesive was placed above the nanostructured membrane mold (with the primer-coated side facing downwards), and was adhered to the nanostructured membrane mold along its leading edge using tape. Resin B beads were placed between the PET and the nanostructured membrane mold along the leading edge of the structure, contacting the primer-coated side of the PET and the nanostructured side of the nanostructured membrane mold. The aluminum plate, nanostructured membrane mold, resin, and PET film structure were then passed through a laminator ("HL-100", purchased from ChemInstruments, Fairfield, OH) at a speed setting of "2" and a pressure of 16 psi (110 kps). The laminated structure was then exposed to radiation from a Phoseon UV LED curing system (FIREJET FJ 300X20AC405-12W, purchased from Phoseon Technology, Hillsboro, OR), operating at 50% power at a speed of 7.6 m / min. Next, membrane F was peeled from the nanostructured membrane mold. Membrane G

[0164] The following procedure was used to prepare membrane G. First, resin D was molded onto a 75-micron-thick biaxially oriented polyethylene terephthalate (PET) film (prepared internally) with an acrylic polymer ("RHOPLEX 3208") tackifier at room temperature. Using a rubber-coated roller, the coated film was pressed onto a nanostructured nickel surface attached to a steel roller controlled at 49°C at a speed of 9.1 m / min. The coating thickness of resin D on the film was sufficient to completely wet the nickel surface, and when the coated film was pressed onto the nanostructured nickel surface, rolled resin beads were formed. The film was exposed to radiation from two UV lamp systems (trademarked "F600" from Fusion UV Systems, Gaithersburg, MD), both equipped with D bulbs and dichroic reflectors and operating at 236 W / cm, while in contact with the nanostructured nickel surface. The nanostructured film G was then peeled off from the nickel surface. Membrane H

[0165] Membrane H was prepared using the following procedure. First, resin D was molded onto a 125-micron-thick polycarbonate film (license plate "LEXAN" from Tekra, Inc., New Berlin, WI) with a glossy finish on both sides at room temperature. Using a rubber-coated roller, the coated film was pressed laterally onto a nanostructured mold attached to a steel roller controlled at 60°C at a speed of 15.2 m / min. The coating thickness of resin D on the film was sufficient to completely wet the nickel surface, and when the coated film was pressed onto the nanostructured nickel surface, rolled resin beads were formed. The film was exposed to radiation from two UV lamp systems ("F600", purchased from Fusion UV Systems), both equipped with D bulbs and dichroic reflectors, and both operated at 142 W / cm, while in contact with the surface of the nanostructured mold. The obtained nanostructured film was peeled off from the surface of the nanostructured mold, and then the nanostructured surface of the film was exposed to radiation from a UV lamp system ("F600", purchased from Fusion UV Systems), which was equipped with a D lamp and a dichroic reflector, and operated at 142 W / cm. membrane I

[0166] Membrane I was prepared using the following procedure. A silicon-containing release layer, according to the methods described in U.S. Patent Nos. 6,696,157 (David et al.), 8,664,323 (Iyer et al.), and U.S. Patent Publication No. 2013 / 0229378 (Iyer et al.), was applied to the nanostructured membrane H in a parallel-plate capacitively coupled plasma reactor to produce nanostructured membrane I. The chamber had a central cylindrical power supply electrode with a surface area of ​​1.7 m² (18.3 ft²). After placing the nanostructured membrane on the power supply electrode, the reactor chamber was pumped to a base pressure of less than 1.3 Pa (2 mTorr). O₂ gas was introduced into the chamber at a rate of 1000 SCCM. Processing was performed using plasma-enhanced CVD by coupling RF power into the reactor at a frequency of 13.56 MHz and an applied power of 2000 watts. The processing time was controlled by moving the nanostructured membrane through the reaction zone at a rate of 9.1 m / min (30 ft / min), resulting in an approximate exposure time of 10 seconds. After deposition, the RF power was turned off and the gas was vented from the reactor. Following the first treatment, a second plasma treatment was performed in the same reactor without returning the chamber to atmospheric pressure. HMDSO gas was flowed into the chamber at approximately 1750 SCCM to achieve a pressure of 9 mTorr. Subsequently, 13.56 MHz RF power was coupled into the reactor at an applied power of 1000 W. The nanostructured membrane was then conveyed through the reaction zone at a rate of 9.1 m / min (30 ft / min), resulting in an approximate exposure time of 10 seconds. At the end of this processing time, the RF power and gas supply were stopped, and the chamber was returned to atmospheric pressure. Membrane J

[0167] The multilayer film J is prepared using the method described in PCT Publication No. WO 2019 / 032635 A1 (Johnson et al.). The resulting multilayer film has a 43-micron polyethylene terephthalate (PET) layer, a 6-7 micron linear BES triblock copolymer ("KRATON G1645") layer, a 6-7 micron blend layer comprising 70 parts by weight of a random polypropylene copolymer ("PP9074MED") and 30 parts by weight of a BES triblock copolymer ("KRATON G1645"), and a 10-micron PETG copolyester ("EASTAR GN071") layer. membrane K

[0168] The nanostructured membrane K is prepared by first attaching the leading edge of the nanostructured membrane I to a 1.6 mm thick aluminum plate with adhesive tape (with the nanostructured surface separated from the aluminum plate). A multilayer membrane J is placed on top of the nanostructured membrane I (with the PETG surface adjacent to the nanostructured surface of the nanostructured membrane I) and attached to the aluminum plate with adhesive tape. The membrane and plate are placed in a 60°C oven for 1 minute. Resin B is heated in the 60°C oven, and a bead of heated resin B is placed between the two membranes. The membrane J / resin B / membrane I / aluminum plate structure is set to speed "1", the upper and lower roller temperatures are set to 60°C, and the pressure is set to 15 psi (103 kPa) using a single-stage laminator (trademarked "Model HL-100" from Cheminstruments, Inc. Fairfield OH). The membrane J / resin B / membrane I / aluminum plate structure was exposed to radiation from a UV LED curing system (trademarked "FIREJET FJ 300X20AC405-12W", obtained from Phoseon Technologies, Hillsboro, OR) operated twice at 25% power and a speed of 15.2 m / min. The nanostructured membrane K was then removed from the nanostructured membrane I. Structured Sample A

[0169] Structured sample A was prepared using the following procedure. A concentrated sol of surface-modified silicon dioxide nanoparticles (Nalco 2326, modified with 3-(methacryloxy)propyltrimethoxysilane) in diethylene glycol monoethyl ether was prepared as described in Example 1 of U.S. Patent Application Publication No. US 2019 / 0185328 (Humpal et al.). The resulting sol contained 45.60% by weight of oxides. To prepare a casting sol, a portion of the concentrated sol (200.14 g) was placed in a 500-mL bottle and combined with diethylene glycol monoethyl ether (1.48 g), HEA (2.83 g, from Alfa Aesar), octyl acrylate (5.68 g), trimethylolpropane triacrylate (SR351 H) (50.00 g), and hexafunctional carbamate acrylate (CN975) (24.95 g). OMNIRAD 819 (6.84 g) was dissolved in diethylene glycol monoethyl ether (174.14 g) and added to a bottle. The casting sol was then passed through a 1-micron filter. The casting sol contained 19.58% by weight of oxide and 56.41% by weight of solvent.

[0170] The casting sol was poured into an acrylic mold cavity (30mm × 30mm × 3mm). One side of the mold cavity formed the structured side of the nanostructured membrane G. The walls of the mold cavity were treated with a release coating. Once the cavity was filled, the casting sol was cured (polymerized) for 30 seconds using an LED array positioned 40mm from the mold surface. In a 10×10 array, the diodes (with a wavelength of 450nm) were spaced 8mm apart. The resulting molded gel replicated the characteristics of the structured membrane tool, exhibiting a dry texture and good handling when removed from the mold. The molded gel was then dried using supercritical CO2 extraction in a manner similar to that described in the example section of U.S. Patent Application Publication No. US 2019 / 0185328 (Humpal et al.). After drying, the molded aerogel was free of cracks. The molded aerogel was placed on a 3-mm diameter quartz rod on a 1-mm thick alumina plate and heated in air to remove organic components and densify. The heating schedule was based on the examples described in U.S. Patent Application Publication No. US 2019 / 0185328 (Humpal et al.), with slight variations in time and temperature. The resulting structured sample A was crack-free, transparent, and accurately replicated the mold features. Structured Sample B

[0171] Structured sample B was prepared using the following procedure. Structured sample A was placed in an ozone cleaner (brand name UVO Cleaner, model 144AX, obtained from Jelight Company, Irvine, CA). A drop of mixture B was then placed on the structured surface of structured sample A using a disposable pipette. Mixture B was then spread onto the structured surface using a #7 wire-wound coating stick (brand name RDS07, obtained from RDSpecialties, Inc., Webster, NY). The coated structured sample A was allowed to dry at room temperature, and then placed in a 75°C oven for 60 minutes to form structured sample B. A 10,000x scanning electron microscope image of the structured surface of the second sample, prepared using the same procedure as structured sample B, is shown in Figure 12A. [Example 1]

[0172] To prepare Example 1 (shown schematically in Figure 4A), the nanostructured surfaces of two films A were laminated together using the following methods: the films were positioned; the leading edges of the films were adhered to a 1.6 mm thick aluminum plate using adhesive tape; the top film was placed above the top roller of a laminator, so that the two films were in contact at the clamping point of the laminator. The films were laminated using a one-piece laminator (trademark name "Model HL-100" from ChemInstruments, Inc. Fairfield OH) at a speed setting of 2 and a pressure of 16 psi (110 kPa). The laminated structure was passed through UV light from a Fusion UV lamp system ("F600") equipped with an H bulb operating at 236 W / cm. The nanostructured layer system of Example 1 was profiled and imaged using an ion mill (Figure 4B). The color correction of Example 1 was measured and recorded in Table 1 below. [Example 2]

[0173] Example 2 (shown schematically in Figure 5A) was prepared by first preparing the bilayer structure of Example 1. Film B was laminated to the structure of Example 1 by: attaching the leading edge of the film to a 1.6 mm thick aluminum plate with tape; placing the top film above the top roller of the laminator so that the films contact at the clamping point of the laminator. The films were then laminated by: placing a bead of resin D along the leading edge of the lower film, and laminating the films using a single-stage laminator ("HL-100") at a speed of 2 and a pressure of 16 psi (110 kPa). The laminated structure was passed through UV light from a Fusion UV lamp system ("F600") equipped with a D bulb, operating at 236 W / cm. Example 2 was cross-sectioned using an ion mill and imaged by SEM (Figures 5B to 5D). The color correction of Example 2 was measured and recorded in Table 1. [Example 3]

[0174] Example 3 (shown schematically in Figure 6A) was prepared by first preparing two bilayer structures of Example 1. The two Example 1 structures were laminated by: attaching the leading edges of the structures to a 1.6 mm thick aluminum plate with tape; placing the top film above the top roller of a laminator so that the films contact each other at the clamping point of the laminator. The films were then laminated by: placing a bead of resin D along the leading edge of the lower film and laminating it using a one-piece laminator ("HL-100") at a speed of 2 and a pressure of 16 psi (110 kPa). The laminated structure was passed through UV light from a Fusion UV lamp system ("F600") equipped with a D bulb operating at 236 W / cm. Example 3 was cross-sectioned using an ion mill and imaged by SEM (Figures 6B to 6D). The color correction of Example 3 was measured and recorded in Table 1. [Example 4]

[0175] Example 4 (shown schematically in Figure 7A) was prepared by laminating two films C using the following procedure. The two films C were laminated by: attaching the leading edges of the films to a 1.6 mm thick aluminum plate with tape; placing the top film above the top roller of the laminator so that the films contact each other at the clamping point of the laminator. The films were then laminated by: placing a bead of resin D along the leading edge of the lower film and laminating it using a one-piece laminator ("HL-100") at a speed of 2 and a pressure of 16 psi (110 kPa). The laminated structure was passed through UV light from a Fusion UV lamp system ("F600") equipped with a D bulb, operating at 236 W / cm. Example 4 was cross-sectioned using an ion mill and imaged by SEM (Figures 7B to 7D). The color correction of Example 4 was measured and recorded in Table 1. [Example 5]

[0176] Example 5 was prepared by laminating the nanostructured surface of membrane A onto the nanostructured surface of membrane E using the following procedure. Membrane A was placed on a 1.6 mm thick aluminum plate with its nanostructured side facing up. Membrane E was placed on top of membrane A with its nanostructured surface facing down. The leading edges of both membranes were taped to the aluminum plate to attach them to the plate. The structure was placed in a laminator ("HL-100") (with the leading edges passing through the clamps), and the laminator clamps were closed. The membranes were laminated at a speed setting of 1, a pressure of 12 psi (110 kPa), and an upper and lower roller temperature setting of 60°C. The laminated structure was then passed through a Fusion UV lamp system ("F600") equipped with a D bulb, operating at 236 W / cm at a speed of 7.6 m / min to produce Example 5. [Example 6]

[0177] Example 6 (shown schematically in Figure 11A) was prepared as follows. A membrane A was placed on a 1.6 mm thick aluminum plate with the nanostructured side facing up. A second membrane F was rotated 90 degrees and placed on top of the first membrane F with the nanostructured side facing down, so that the linear orientations of the nanostructures of the two membranes were approximately orthogonal. The two membranes were attached to the aluminum plate and laminated and exposed to radiation using the same procedure as in Example 5, with a speed setting of 2. The resulting Example 6 was cross-sectionally obtained by rupture in liquid nitrogen, and the nanostructured region was imaged using SEM (Figure 11B). [Example 7]

[0178] Example 7 was prepared by laminating the nanostructured side of the nanostructured film K onto the nanostructured surface of the structured sample B using a manual roller. The laminated nanostructured film K side was exposed to radiation from a UV lamp system ("F600", purchased from Fusion UV Systems), which was equipped with a D lamp and a dichroic reflector, and operated twice at a speed of 15.2 m / min at 236 W / cm. The PET, triblock copolymer layer, and polypropylene layer were removed from the structure. The resulting Example 7 was cross-sectionally prepared by applying a piece of adhesive tape to the unstructured side of the structured sample B, grasping Example 7 with two glass clamps, and bending Example 7. The resulting cross-section was imaged using a scanning electron microscope, and the resulting 20,000x magnification micrograph is shown in Figure 12B. [Comparative Example 1:]

[0179] As described above, membrane C was prepared. Color correction was measured and recorded in Table 1. [Comparative Example 2]

[0180] Membrane A was prepared and backfilled using the backfill formulation described in Example 4 of U.S. Patent Application No. US2019 / 0338142 A1 (Hartmann-Thompson et al.), except that the nanoparticle solution comprised 68% and the resin mixture comprised 32% of the backfill formulation. The color correction of Comparative Example 2 was measured and is described in Table 1.

[0181] All patents and patent applications mentioned above are hereby expressly incorporated herein by reference. In the event of any inconsistency between the disclosure of this application and the disclosure of any document(s) incorporated herein by reference, the disclosure of this application shall prevail. The above embodiments are illustrative of the invention, and other configurations are also possible. Accordingly, the invention should not be construed as limited to the embodiments detailed above and shown in the accompanying drawings, but rather as limited only by the scope of the claims that follow in conjunction with their equivalents.

[0182] 100: First gap 110: First floor 111: Sidewall 112: Nanostructured First Surface 114: Nanoscale characteristics 116: Relative to the second surface 119: Prominent Features 120: Second floor 122: Nanostructured First Surface 124: Nanoscale characteristics 126: Relative to the second surface 129: Prominent Features 130: Third Floor 131: Nonlinear surface; curved surface 132: Nanostructured First Surface 134: Nanoscale characteristics 135: Gap 136: Relative to the second surface 137: Groove feature 140: Fourth Floor 142: First primary surface 144: Relative to the second primary surface 150: Fifth Floor 152: First primary surface 160: Sixth Floor 200: Items 210: First Floor 212: Nanostructured First Surface 214: Nanoscale characteristics 215: Curved surface 216: Relative to the second surface 219: Prominent Features 220: Second Floor 222: First primary surface 224: Relative to the second primary surface 230: Third Floor 232: Nanostructured First Surface 234: Nanoscale characteristics 235: Gap 236: Relative to the second surface 237: Groove feature 239: Prominent Features 240: Fourth Floor 242: First primary surface 244: Second primary surface 250: Fifth Floor 252: First primary surface 254: Relative to the second primary surface 260: The Sixth Floor 262: First primary surface 264: Relative to the second primary surface 270: Seventh Floor 272: First primary surface 274: Relative to the second primary surface 280: Eighth Floor 282: First primary surface 300: Items 310: OLED 320: Item Layer 400: First gap 410: First Floor 414: Nanoscale characteristics 420: Second layer 424: Nanoscale characteristics 430: Third Floor 440: Fourth Floor 450: Fifth Floor 460: Sixth Floor 470: Seventh Floor 480: Eighth Floor 500: First gap 510: First Floor 514: Nanoscale characteristics 520: Second layer 524: Nanoscale characteristics 530: Third Floor 534: Nanoscale characteristics 535: Second gap 540: Fourth Floor 551: Fifth Floor 553: Sixth Floor 555: Seventh Floor 561: Eighth Floor 563: Ninth Floor 565: The Tenth Floor 571: Eleventh Floor 573: The Twelfth Floor 575: The Thirteenth Floor 600: First gap 610: First Floor 614: Nanoscale characteristics 620: Second layer 624: Nanoscale characteristics 630: Third Floor 634: Nanoscale characteristics 635: First Gap 640: Fourth Floor 644: Nanoscale characteristics 651: Fifth Floor 653: Sixth Floor 655: Seventh Floor 661: Eighth Floor 663: Ninth Floor 665: The Tenth Floor 671: Eleventh Floor 673: The Twelfth Floor 675: The Thirteenth Floor 700: Gap 710: First Floor 714: Nanoscale characteristics 720: Second Layer 730: Third Floor 734: Nanoscale characteristics 735: Gap 740: Fourth Floor 751: Fifth Floor 753: Sixth Floor 755: Seventh Floor 761: Eighth Floor 763: Ninth Floor 765: The Tenth Floor 771: Eleventh Floor 773: The Twelfth Floor 775: The Thirteenth Floor 1000: Items 1010: First Surface 1020: First Surface 1100: One of the characteristics of nanoscale is the linear nanostructure. 1200: One of the characteristics of nanoscale is a linear nanostructure. 2000: Items 4000: Items 5000: Items 6000: Items 7000: Items 11000: Items 12000: Items D1: Direction D2: Orthogonal direction H: Height W: Width

Claims

1. An article having a nanostructured surface, comprising: a) a first layer comprising a nanostructured first surface including nano-features and an opposing second surface, wherein the nanostructured first surface includes a groove-like feature or a protruding feature, or both groove-like and protruding features, formed from a single component; and b2) a third layer comprising a nanostructured first surface including nano-features and an opposing second surface, wherein a portion of the nano-features of the third layer is attached to a portion of the nano-features of the first layer, and wherein the nanostructured first surface of the third layer and the nanostructured first surface of the first layer together define at least one second void, the second void containing gas or vacuum to provide refractive index contrast; wherein: 1) The first layer comprises an inorganic material containing a coupling agent bonded to the nanostructured first surface of the first layer, or 2) The first layer comprises an organic material and includes crosslinking between the first layer and the third layer.

2. The article containing a nanostructured surface as claimed in claim 1, wherein the article further comprises: e) a sixth layer comprising a nanostructured first surface including nano-features and an opposing second surface; and f) a seventh layer comprising a first main surface and an opposing second main surface, wherein the first main surface is attached to a portion of the nano-features of the sixth layer, and wherein the nanostructured first surface of the sixth layer and the first main surface of the seventh layer together define at least a fourth void, wherein the second surface of the sixth layer or the second main surface of the seventh layer is adjacent to the second main surface of the third layer or adjacent to the second surface of the first layer.

3. The article containing a nanostructured surface as claimed in claim 1, wherein the article further comprises: g) an eighth layer comprising a nanostructured first surface including nano-features and an opposing second surface; and h) a ninth layer comprising a nanostructured first surface including nano-features and an opposing second surface, wherein a portion of the nano-features of the ninth layer is attached to a portion of the nano-features of the eighth layer, and wherein the nanostructured first surface of the ninth layer and the nanostructured first surface of the eighth layer together define at least a fifth void, wherein the second surface of the eighth layer or the second surface of the ninth layer is adjacent to the second surface of the third layer or adjacent to the second surface of the first layer.

4. The article containing a nanostructured surface as claimed in claim 3, wherein at least one of the first layer, the eighth layer, or the ninth layer contains nano features having at least one nonlinear surface in at least one direction.

5. An article with a nanostructured surface as claimed in claim 1, wherein each of the nanostructured first surface of the first layer and the nanostructured first surface of the third layer contains nano-feature lines, and wherein the nano-feature lines of the first layer and the nano-feature lines of the third layer intersect at an angle of 80 to 100 degrees.

6. The article containing a nanostructured surface as claimed in claim 1, wherein at least one of the first layer or the third layer comprises an acrylic polymer or copolymer.

7. An article having a nanostructured surface, comprising: a) a first layer including a nanostructured first surface comprising nano-features and an opposing second surface, wherein the nanostructured first surface includes a groove-like feature or a protruding feature, or both groove-like and protruding features, formed from a single component; and b) a second layer including a first main surface and an opposing second main surface, the first main surface being attached to a portion of the nano-features of the first layer, wherein the nanostructured first surface of the first layer and the first main surface of the second layer together define at least a first void containing gas or vacuum to provide refractive index contrast; wherein: 1) The first layer comprises an inorganic material containing a coupling agent bonded to the nanostructured first surface of the first layer; or 2) The first layer comprises an organic material and includes crosslinking between the first layer and the second layer; and c) A fourth layer comprising a nanostructured first surface including nano-features and an opposing second surface, wherein the second surface of the fourth layer or the nanostructured first surface of the fourth layer is adjacent to the second main surface of the second layer or adjacent to the second surface of the first layer.

8. The article containing a nanostructured surface as claimed in claim 7, wherein the article further comprises: d) a fifth layer comprising a first main surface and an opposing second main surface, wherein the first main surface is attached to a portion of the nano feature of the fourth layer, wherein the nanostructured first surface of the fourth layer and the first main surface of the fifth layer together define at least a third void.

9. The article containing a nanostructured surface as claimed in claim 7, wherein the article further comprises: i) a tenth layer comprising a nanostructured first surface including nano-features and an opposing second surface; and j) an eleventh layer comprising a nanostructured first surface including nano-features and an opposing second surface, wherein a portion of the nano-features of the eleventh layer is attached to a portion of the nano-features of the tenth layer, and wherein the nanostructured first surface of the eleventh layer and the nanostructured first surface of the tenth layer together define at least a sixth void, wherein the second surface of the tenth layer or the second surface of the eleventh layer is adjacent to the second main surface of the second layer or adjacent to the second surface of the first layer.

10. The article containing a nanostructured surface as claimed in claim 7, further comprising a twelfth layer disposed adjacent to the second main surface of the second layer or the second surface of the first layer.

11. An article containing a nanostructured surface as claimed in claim 10, wherein the twelfth layer is a low birefringence layer.

12. The article containing a nanostructured surface as claimed in claim 7, further comprising a thirteenth layer disposed adjacent to the second main surface of the second layer or the second surface of the first layer.

13. An article containing a nanostructured surface, as claimed in claim 7, wherein the second layer is substantially flat.

14. The article containing a nanostructured surface as claimed in claim 7, wherein at least one of the first layer or the second layer comprises an acrylic polymer or copolymer.

15. The article containing a nanostructured surface as claimed in claim 9, wherein at least one of the first layer, the tenth layer, or the eleventh layer includes nano features having at least one non-linear surface in at least one direction.

16. An optical information display comprising an article having a nanostructured surface as claimed in any one of claims 1 to 15.

17. An OLED device comprising an article having a nanostructured surface as claimed in any one of claims 1 to 15.

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