Antireflective article comprising a multilayer antireflective coating

Abstract

An anti-reflective article includes a multilayer anti-reflective coating disposed on a major surface of a substrate. The multilayer anti-reflective coating includes an N number of bilayers, each bilayer including a high index layer (HIL) of a high index material and a low index layer (LIL) of a low index material. The high index layer exhibits a HIL resistivity (p) greater than or equal to 1.0 Ω-cm and a HIL extinction coefficient (k) greater than or equal to 0.15 for electromagnetic radiation having a wavelength of 500 nm. The anti-reflective article exhibits an average transmittance in a range from 25% to 90% for visible electromagnetic radiation passing therethrough. The anti-reflective article exhibits an average 1 -sided reflectance less than or equal to 1.0% for visible electromagnetic radiation incident on the multilayer anti-reflective coating.

Description

Technical Field

[0001] This disclosure generally relates to antireflective articles such as those comprising a multilayer antireflective coating disposed on a substrate for use in displays with touchscreen functionality, and more specifically, such multilayer antireflective coatings having at least one high refractive index layer having a resistivity (ρ) greater than or equal to 1.0 Ω·cm and an extinction coefficient (k) greater than or equal to 0.15 for electromagnetic radiation having a wavelength of 500 nm. Background Technology

[0002] Vehicles sometimes include electronic displays located behind polymer or glass substrates, such as in the dashboard or cockpit area. When activated, the display conveys information to the vehicle's users or passengers. A trend is towards visually concealing the display when not in use—an aesthetic sometimes referred to as a "hidden panel." Furthermore, reducing the reflectivity of the polymer or glass substrate is desirable to enhance display readability and allow the substrate to better integrate with other materials within the vehicle. Multi-layered coatings utilizing anti-interference properties can be applied to the substrate's main surface to reduce reflectivity. Additionally, there is a desire to enhance the display's functionality by incorporating touchscreen capabilities. Touchscreen functionality typically relies on detectable changes in capacitance (due to human touch). Therefore, the display will function as a two-way human-machine interface.

[0003] However, there is a problem: the typical multi-layer coatings designed to reduce reflectivity can hinder touchscreen functionality. In short, it is currently impossible to reduce the substrate's reflectivity through a multi-layer coating that does not impede touchscreen responsiveness while maintaining the understated aesthetics of the underlying display panel. Summary of the Invention

[0004] This disclosure addresses this problem (and other problems) in various ways. Among them, this disclosure describes an antireflective article having a multilayer antireflective coating that exhibits low reflectivity without interfering with touchscreen functionality.

[0005] According to a first aspect of this disclosure, an antireflective article comprises: a substrate including a main surface; and a multilayer antireflective coating disposed on the main surface of the substrate, the multilayer antireflective coating comprising N double layers, each double layer comprising: (a) a high refractive index layer (HIL) of a high refractive index material exhibiting (i) HIL refractive index, (ii) HIL resistivity (ρ), and (iii) HIL extinction coefficient (k); and (b) a low refractive index layer (LIL) of a low refractive index material disposed on the high refractive index layer and located further from the main surface than the high refractive index layer, wherein the low refractive index layer is more sensitive to electromagnetic radiation having a wavelength of 550 nm. The antireflective coating exhibits a refractive index of less than that of HIL, wherein (i) the resistivity (ρ) of HIL is greater than or equal to 1.0 Ω·cm, (ii) the extinction coefficient (k) of HIL for electromagnetic radiation with a wavelength of 500 nm is greater than or equal to 0.15, (iii) the antireflective coating exhibits an average transmittance in the range of 25% to 90% for visible electromagnetic radiation passing through it at an angle of incidence perpendicular to the main surface, and (iv) the antireflective coating exhibits an average 1-sided reflectance of less than or equal to 1.0% for visible electromagnetic radiation incident on it at an angle of 10 degrees relative to the normal of the main surface.

[0006] According to a second aspect of this disclosure, an antireflective article of the first aspect is provided, wherein the substrate comprises a glass composition, a glass-ceramic composition, or a polymer composition.

[0007] According to a third aspect of this disclosure, an antireflective article of any one of the first to second aspects is provided, wherein the substrate has a substrate thickness in the range of 30 μm to 3.1 mm measured perpendicular to the main surface.

[0008] According to a fourth aspect of this disclosure, an antireflective article of the third aspect is provided, wherein the substrate thickness is in the range of 300 μm to 1.3 mm.

[0009] According to the fifth aspect of this disclosure, an antireflective article of any one of the first to fourth aspects is provided, wherein N is an integer in the range of 2 to 13.

[0010] According to the sixth aspect of this disclosure, an antireflective article of any one of the first to fifth aspects is provided, wherein the refractive index of HIL is in the range of 1.7 to 2.8.

[0011] According to the seventh aspect of this disclosure, an antireflective article of the sixth aspect is provided, wherein the refractive index of HIL is in the range of 2.4 to 2.8.

[0012] According to the eighth aspect of this disclosure, an antireflective article of any one of the first to seventh aspects is provided, wherein the refractive index of the LIL is in the range of 1.3 to 2.1.

[0013] According to the ninth aspect of this disclosure, an antireflective article of the eighth aspect is provided, wherein the refractive index of the LIL is in the range of 1.3 to 1.5.

[0014] According to the tenth aspect of this disclosure, an antireflective article of any one of the first to ninth aspects is provided, wherein the high refractive index material of at least one of the N number of bilayers comprises TiNbO x VON and SiN y One or more of them.

[0015] According to the eleventh aspect of this disclosure, an antireflective article of the tenth aspect is provided, wherein at least one of the N number of bilayers comprises TiNbO. x .

[0016] According to the twelfth aspect of this disclosure, an antireflective article is provided for any one of the first to eleventh aspects, wherein the high refractive index material of at least one of the N number of bilayers comprises a metal dispersed in a ceramic matrix.

[0017] According to the thirteenth aspect of this disclosure, an antireflective article of any one of the first to twelfth aspects is provided, wherein at least one of the N number of bilayers comprises a low refractive index material including SiO2, MgF2, YF3, and SiN. y One or more of YbF3.

[0018] According to the fourteenth aspect of this disclosure, an antireflective article of any one of the first to thirteenth aspects is provided, wherein the high refractive index material of the high refractive index layer of one of the N number of bilayers is the low refractive index material of the low refractive index layer of the other of the N number of bilayers.

[0019] According to the fifteenth aspect of this disclosure, an antireflective article of the fourteenth aspect is provided, wherein (i) SiN y It is a high-refractive-index material that is one of N bilayers, and (ii)SiN y It is a low-refractive-index material that is the low-refractive-index layer of another of N double layers.

[0020] According to the sixteenth aspect of this disclosure, an antireflective article of any one of the first to fifteenth aspects is provided, wherein the resistivity (ρ) of HIL is greater than or equal to 2.0 Ω·cm.

[0021] According to the seventeenth aspect of this disclosure, an antireflective article of any one of the first to sixteenth aspects is provided, wherein the HIL extinction coefficient (k) for electromagnetic radiation having a wavelength of 500 nm is greater than or equal to 0.30.

[0022] According to the eighteenth aspect of this disclosure, an antireflective article of any one of the first to seventeenth aspects is provided, wherein at least one of the N number of bilayers exhibits an HIL extinction coefficient (k) that varies less than 0.2 over the entire wavelength range of 400 nm to 800 nm.

[0023] According to the nineteenth aspect of this disclosure, an antireflective article of any one of the first to eighteenth aspects is provided, wherein each of the N number of bilayers has a high refractive index layer having a HIL thickness in the range of 10 nm to 80 nm.

[0024] According to the twentieth aspect of this disclosure, an antireflective article of any one of the first to nineteenth aspects is provided, wherein each of the N number of bilayers has a low refractive index layer having a LIL thickness in the range of 5 nm to 150 nm.

[0025] According to the twenty-first aspect of this disclosure, an antireflective article of any one of the first to twentieth aspects is provided, wherein the multilayer antireflective coating has a coating thickness of less than or equal to 450 nm measured perpendicular to the main surface.

[0026] According to the twenty-second aspect of this disclosure, an antireflective article of any one of the first to twenty-first aspects is provided, wherein the multilayer antireflective coating further comprises an initial low-refractive-index layer of a low-refractive-index material on the main surface of a substrate, the initial low-refractive-index layer being sandwiched between the main surface of the substrate and N number of double layers.

[0027] According to the twenty-third aspect of this disclosure, an antireflective article of any one of the first to twenty-second aspects is provided, wherein the antireflective article exhibits an average transmittance in the range of 50% to 80%.

[0028] According to the twenty-fourth aspect of this disclosure, an antireflective article of any one of the first to twenty-second aspects is provided, wherein the antireflective article exhibits an average transmittance in the range of 39% to 52%.

[0029] According to the twenty-fifth aspect of this disclosure, an antireflective article is provided for any one of the first to twenty-fourth aspects, wherein, for visible electromagnetic radiation passing through the antireflective article at an incident angle perpendicular to the main surface of the substrate, the antireflective article exhibits a transmitted color characterized by the CIELAB color space having an L* value in the range of 60 to 85, an a* value in the range of 0 to 5.0, and a b* value in the range of 0 to 8.0.

[0030] According to the twenty-sixth aspect of this disclosure, an antireflective article is provided for any one of the first to twenty-fifth aspects, wherein, for visible electromagnetic radiation incident on a multilayer antireflective coating at an incident angle deviating 10 degrees from the normal of the main surface of the substrate, the antireflective article exhibits a reflected color characterized by the CIELAB color space having an L* value in the range of >0 to 6.0, an a* value in the range of -5.0 to 0, and a b* value in the range of -5.0 to 0.

[0031] According to the twenty-seventh aspect of this disclosure, an antireflective article of any one of the first to twenty-sixth aspects is provided, wherein the antireflective article exhibits (i) a hardness greater than or equal to 6.5 GPa as measured by a Berkovich nanoindentation test at an indentation depth of about 100 nm in a multilayer antireflective coating and (ii) an elastic modulus greater than or equal to 60 GPa as measured by a Berkovich nanoindentation test at an indentation depth of about 100 nm in a multilayer antireflective coating.

[0032] According to the 28th aspect of this disclosure, an antireflective article of any one of the first to 27 aspects is provided, wherein the antireflective article exhibits a failure stress greater than 1500 MPa.

[0033] According to the twenty-ninth aspect of this disclosure, an antireflective article of any one of the first to twenty-eighth aspects is provided, wherein the antireflective article exhibits a failure strain greater than 1.5%.

[0034] According to the thirtieth aspect of this disclosure, an antireflective article of any one of the first to twenty-ninth aspects is provided, wherein the high refractive index layer of at least one of a number of bilayers is formed by co-sputtering a high refractive index material from at least two different source materials.

[0035] According to the thirty-one aspect of this disclosure, an antireflective article of the thirtieth aspect is provided, wherein at least two different source materials comprise Ti metal and NbO. x ceramics.

[0036] According to the thirty-second aspect of this disclosure, the touchscreen display comprises: an electronic display; an antireflective article of any one of the first to thirty-first aspects, said antireflective article being positioned on the electronic display such that visible electromagnetic radiation transmitted by the electronic display is at least partially transmitted through the antireflective article to the external environment; and a touchscreen layer disposed between the antireflective article and the electronic display.

[0037] According to the thirty-third aspect of this disclosure, a method for manufacturing an antireflective article of any one of the first to thirty-first aspects is provided, the method comprising: a co-sputtering step, the co-sputtering step comprising simultaneously sputtering a first source material comprising Ti and a source material comprising NbO in the presence of O2 and Ar.x The second source material, thereby forming at least one of N bilayers of high refractive index layer.

[0038] Additional features and advantages are set forth in the following detailed description and, in part, will be readily apparent to those skilled in the art or will be recognized by practicing the embodiments described herein, including the following detailed description, claims, and drawings.

[0039] It should be understood that the foregoing general description and the following detailed description are merely exemplary and intended to provide an overview or framework for understanding the nature and features of the claims. Drawings are included to provide further understanding and are incorporated in and constitute a part of this specification. The drawings illustrate one or more embodiments and, together with the description, serve to explain the principles and operation of the various embodiments. Attached Figure Description

[0040] In the attached diagram:

[0041] Figure 1 This is a top perspective view of the antireflective article disclosed herein, showing a multilayer antireflective coating disposed on a substrate;

[0042] Figure 2 yes Figure 1 An elevation view of the cross-section of an antireflective article, showing a multilayer antireflective coating consisting of an initial low refractive index layer, followed by N numbers of high refractive index layers and low refractive index layers (on top of the high refractive index layers).

[0043] Figure 3 This is a cross-sectional elevation view of a touchscreen display, showing the electronic display, the touchscreen layer on the electronic display, and the components mounted on the touchscreen layer. Figure 1 Anti-reflective products;

[0044] Figure 4 It is manufacturing Figure 1 A schematic diagram of a method for producing an antireflective article illustrates a co-sputtering step, during which a first source material (e.g., titanium metal) is sputtered with (e.g., NbO) x The second source material is simultaneously sputtered onto the substrate to form a high-refractive-index layer, one of N bilayers;

[0045] Regarding Example 1 Figure 5 TiNbO formed by co-sputtering x A graph showing the refractive index (n) and extinction coefficient (k) of the layer as a function of the wavelength of electromagnetic radiation, demonstrating that the two values ​​are relatively constant throughout the visible spectrum;

[0046] Regarding Example 2 Figure 6 It is SiO xA graph showing the refractive index (n) and extinction coefficient (k) of a layer as a function of the wavelength of electromagnetic radiation, showing the extinction coefficient (k) as zero and therefore not all materials exhibit a material extinction coefficient (k);

[0047] Regarding Example 3 Figure 7 It is SiN y A graph showing the refractive index (n) and extinction coefficient (k) of a layer as a function of the wavelength of electromagnetic radiation, showing an extinction coefficient (k) of zero and therefore not all materials exhibit a material extinction coefficient (k) in the visible spectrum;

[0048] Regarding Examples 4-10 Figure 8 TiNbO is formed by co-sputtering under variable conditions. x A graph showing the refractive index (n) of the layer as a function of the wavelength of electromagnetic radiation, illustrating how a higher amount of titanium in the layer reduces the refractive index (n).

[0049] Regarding Examples 4-10 Figure 9 TiNbO is formed by co-sputtering under variable conditions. x A graph showing the extinction coefficient (k) of the layer as a function of the wavelength of electromagnetic radiation, illustrating that these layers can be formed such that the extinction coefficient (k) shown is of material and relatively constant throughout the visible range;

[0050] Regarding Examples 33-35 Figure 10 The image shows the antireflective article of this disclosure, depicting a light gray color;

[0051] Regarding Example 33 Figure 11 A pair of graphs are provided for the antireflective article of this disclosure: one graph plots the transmittance as a function of wavelength and the other graph plots the reflectance as a function of wavelength, showing that the multilayer antireflective coating thereon sufficiently absorbs visible light while reflecting very little visible light.

[0052] Regarding Example 34 Figure 12 A pair of graphs are provided for the antireflective article of this disclosure: one graph plots the transmittance as a function of wavelength and the other graph plots the reflectance as a function of wavelength, showing that the multilayer antireflective coating thereon sufficiently absorbs visible light while reflecting very little visible light.

[0053] Regarding Example 35 Figure 13 A pair of graphs are provided for the antireflective article of this disclosure: one graph plots the transmittance as a function of wavelength and the other graph plots the reflectance as a function of wavelength, showing that the multilayer antireflective coating thereon sufficiently absorbs visible light while reflecting very little visible light.

[0054] Regarding Example 34 Figure 14 It is a graph plotting the elastic modulus and hardness of the antireflective article of this disclosure, as determined by the Berkovich nanoindentation test.

[0055] Regarding Example 39 Figure 15 This is a graph plotting the failure probability of samples of the antireflective articles of this disclosure as a function of failure stress during ring-to-ring load testing; and

[0056] Regarding Example 40 Figure 16 Images are provided showing damage marks produced in a multilayer antireflective coating of the antireflective article of this disclosure before (before exposure) and after (after exposure) contact with petrolatum oil, demonstrating the resistance of the multilayer antireflective coating to peeling. Detailed Implementation

[0057] Reference will now be made in detail to preferred embodiments of the invention, examples of which are illustrated in the accompanying drawings. Wherever possible, the same reference numerals are used throughout the drawings to refer to the same or similar parts.

[0058] See Figure 1 and 2 This document discloses an antireflective article 10. The antireflective article 10 includes a substrate 12 and a multilayer antireflective coating 14. The multilayer antireflective coating 14 is disposed on the substrate 12.

[0059] The substrate 12 includes a main surface 16. The main surface 16 of the substrate 12 may be generally flat, but is not necessarily so. A multilayer antireflective coating 14 is disposed on the main surface 16 of the substrate 12. In embodiments, the substrate 12 is or includes a glass composition, a glass-ceramic composition, or a polymer composition.

[0060] Suitable glass compositions for substrate 12 include soda-lime glass, aluminosilicate glass, borosilicate glass, borosilicate glass, alkali aluminosilicate glass, alkali borosilicate glass, and alkali borosilicate glass.

[0061] Unless otherwise specified, the glass compositions disclosed herein are described as molar percentages (mol%) based on oxide analysis.

[0062] In an embodiment, the glass composition comprises an amount of SiO2 ranging from 66 mol% to 80 mol%. For example, the molar percentage of SiO2 in the glass composition may be 66 mol%, 67 mol%, 68 mol%, 69 mol%, 70 mol%, 71 mol%, 72 mol%, 73 mol%, 74 mol%, 75 mol%, 76 mol%, 77 mol%, 78 mol%, 79 mol%, 80 mol%, or any range defined by any two of those values ​​(e.g., 67 mol% to 77 mol%, 72 mol% to 76 mol%, etc.).

[0063] In an embodiment, the glass composition comprises an amount of Al2O3 ranging from 2.0 mol% to 15 mol%. For example, the molar percentage of Al2O3 in the glass composition may be 2.0 mol%, 3.0 mol%, 4.0 mol%, 5.0 mol%, 6.0 mol%, 7.0 mol%, 8.0 mol%, 9.0 mol%, 10 mol%, 11 mol%, 12 mol%, 13 mol%, 14 mol%, 15 mol%, or any range defined by any two of those values ​​(e.g., 5.0 mol% to 11 mol%, 6.0 mol% to 13 mol%, etc.).

[0064] In embodiments, the glass composition comprises an amount of B2O3 ranging from greater than 0 mol% to 5.0 mol%. For example, the molar percentage of B2O3 in the glass composition may be greater than 0 mol%, 0.5 mol%, 1.0 mol%, 1.5 mol%, 2.0 mol%, 2.5 mol%, 3.0 mol%, 3.5 mol%, 4.0 mol%, 4.5 mol%, 5.0 mol%, or any two of those values ​​within any range (e.g., 0.5 mol% to 2.0 mol%, 1.0 mol% to 4.5 mol%, etc.). The glass composition may be substantially free of B2O3. As used herein, the phrase "substantially free" regarding the composition of the glass composition means that the component was not actively or intentionally added to the composition during initial batching but may be present as an impurity in an amount less than about 0.001 mol%.

[0065] In embodiments, the glass composition comprises an amount of P2O5 ranging from greater than 0 mol% to 2.0 mol%. For example, the molar percentage of P2O5 in the glass composition may be greater than 0 mol%, 0.2 mol%, 0.4 mol%, 0.6 mol%, 0.8 mol%, 1.0 mol%, 1.2 mol%, 1.4 mol%, 1.6 mol%, 1.8 mol%, 2.0 mol%, or any two of those values ​​within any range (e.g., 0.2 mol% to 1.8 mol%, 0.4 mol% to 1.4 mol%, etc.). The glass composition may be substantially free of P2O5.

[0066] In embodiments, the glass composition comprises an amount of R2O ranging from 8.0 mol% to 20 mol% (which is the total amount of alkali metal oxides such as Li2O, Na2O, K2O, Rb2O, and Cs2O). For example, the molar percentage of R2O in the glass composition may be 8.0 mol%, 9.0 mol%, 10 mol%, 11 mol%, 12 mol%, 13 mol%, 14 mol%, 15 mol%, 16 mol%, 17 mol%, 18 mol%, 19 mol%, 20 mol%, or any range defined by any two of those values ​​(e.g., 9.0 mol% to 18 mol%, 11 mol% to 14 mol%, etc.). The glass composition may be substantially free of R2O. In embodiments, the glass composition may be substantially free of Rb2O, Cs2O, or Rb2O and Cs2O. In embodiments, one or more of Li2O, Na2O, and K2O are the only alkali metal oxides present in the glass composition. In this embodiment, the glass composition is substantially free of Li₂O. In this embodiment, the molar percentage of Na₂O in the composition is greater than the molar percentage of Li₂O. In some cases, the molar percentage of Na₂O may be greater than the combined molar percentage of Li₂O and K₂O. Alternatively, the molar percentage of Li₂O may be greater than the molar percentage of Na₂O or the combined molar percentage of Na₂O and K₂O.

[0067] In an embodiment, the glass composition comprises an amount of Na₂O ranging from 8.0 mol% to 20 mol%. For example, the molar percentage of Na₂O in the glass composition may be 8.0 mol%, 9.0 mol%, 10 mol%, 11 mol%, 12 mol%, 13 mol%, 14 mol%, 15 mol%, 16 mol%, 17 mol%, 18 mol%, 19 mol%, 20 mol%, or any range defined by any two of those values ​​(e.g., 9.0 mol% to 18 mol%, 11 mol% to 14 mol%, etc.).

[0068] In embodiments, the glass composition comprises an amount of K₂O ranging from greater than 0 mol% to 4.0 mol%. For example, the molar percentage of K₂O in the glass composition may be greater than 0 mol%, 0.2 mol%, 0.4 mol%, 0.6 mol%, 0.8 mol%, 1.0 mol%, 1.2 mol%, 1.4 mol%, 1.6 mol%, 1.8 mol%, 2.0 mol%, 2.2 mol%, 2.4 mol%, 2.6 mol%, 2.8 mol%, 3.0 mol%, 3.2 mol%, 3.4 mol%, 3.6 mol%, 3.8 mol%, 4.0 mol%, or any two of those values ​​within any range (e.g., 0.2 mol% to 2.2 mol%, 0.6 mol% to 2.8 mol%, etc.). The glass composition may be substantially K₂O-free.

[0069] In embodiments, the glass composition comprises an amount of RO (which is the total amount of alkaline earth metal oxides such as CaO, MgO, BaO, ZnO, and SrO) ranging from greater than 0 mol% to 2.0 mol%. For example, the molar percentage of RO in the glass composition may be greater than 0 mol%, 0.2 mol%, 0.4 mol%, 0.6 mol%, 0.8 mol%, 1.0 mol%, 1.2 mol%, 1.4 mol%, 1.6 mol%, 1.8 mol%, 2.0 mol%, or any two of those values ​​within any range (e.g., 0.2 mol% to 1.8 mol%, 0.6 mol% to 1.4 mol%, etc.). The glass composition may be substantially RO-free.

[0070] In embodiments, the glass composition comprises an amount of CaO ranging from greater than 0 mol% to 1.0 mol%. For example, the molar percentage of CaO in the glass composition may be greater than 0 mol%, 0.1 mol%, 0.2 mol%, 0.3 mol%, 0.4 mol%, 0.5 mol%, 0.6 mol%, 0.7 mol%, 0.8 mol%, 0.9 mol%, 1.0 mol%, or any two of those values ​​within any range (e.g., 0.2 mol% to 0.8 mol%, 0.3 mol% to 0.9 mol%, etc.). The glass composition may be substantially free of CaO.

[0071] In embodiments, the glass composition comprises an amount of MgO ranging from greater than 0 mol% to 7.0 mol%. For example, the molar percentage of MgO in the glass composition may be greater than 0 mol%, 0.5 mol%, 1.0 mol%, 1.5 mol%, 2.0 mol%, 2.5 mol%, 3.0 mol%, 3.5 mol%, 4.0 mol%, 4.5 mol%, 5.0 mol%, 5.5 mol%, 6.0 mol%, 6.5 mol%, 7.0 mol%, or any two of those values ​​within any range (e.g., 0.5 mol% to 6.0 mol%, 1.5 mol% to 3.0 mol%, etc.). The glass composition may be substantially free of MgO.

[0072] In embodiments, the glass composition comprises a ZrO2 amount ranging from greater than 0 mol% to 0.20 mol%. For example, the molar percentage of ZrO2 in the glass composition may be greater than 0 mol%, 0.02 mol%, 0.04 mol%, 0.06 mol%, 0.08 mol%, 0.10 mol%, 0.12 mol%, 0.14 mol%, 0.16 mol%, 0.18 mol%, 0.20 mol%, or any two of those values ​​within any range (e.g., 0.02 mol% to 0.10 mol%, 0.04 mol% to 0.14 mol%, etc.). The glass composition may be substantially free of ZrO2.

[0073] In embodiments, the glass composition comprises an amount of SnO2 ranging from greater than 0 mol% to 0.20 mol%. For example, the molar percentage of SnO2 in the glass composition may be greater than 0 mol%, 0.02 mol%, 0.04 mol%, 0.06 mol%, 0.08 mol%, 0.10 mol%, 0.12 mol%, 0.14 mol%, 0.16 mol%, 0.18 mol%, 0.20 mol%, or any two of those values ​​within any range (e.g., 0.02 mol% to 0.10 mol%, 0.04 mol% to 0.14 mol%, etc.). The glass composition may be substantially SnO2-free.

[0074] In some embodiments, the glass composition includes an oxide that imparts color or luster to the substrate 12. In some embodiments, the glass composition includes an oxide that prevents the substrate 12 from fading when exposed to ultraviolet radiation. Examples of such oxides include, but are not limited to, oxides of Ti, V, Cr, Mn, Fc, Co, Ni, Cu, Cc, W, and Mo.

[0075] In embodiments, the glass composition comprises an amount of Fe₂O₃ ranging from greater than 0 mol% to 1.0 mol%. For example, the molar percentage of Fe₂O₃ in the glass composition may be greater than 0 mol%, 0.1 mol%, 0.2 mol%, 0.3 mol%, 0.4 mol%, 0.5 mol%, 0.6 mol%, 0.7 mol%, 0.8 mol%, 0.9 mol%, 1.0 mol%, or any two of those values ​​within any range (e.g., 0.2 mol% to 1.0 mol%, 0.4 mol% to 0.8 mol%, etc.). The glass composition may be substantially free of Fe₂O₃.

[0076] In an embodiment, the glass composition comprises an amount of TiO2 ranging from greater than 0 mol% to 5.0 mol%. For example, the molar percentage of TiO2 in the glass composition may be greater than 0 mol%, 0.5 mol%, 1.0 mol%, 1.5 mol%, 2.0 mol%, 2.5 mol%, 3.0 mol%, 3.5 mol%, 4.0 mol%, 4.5 mol%, 5.0 mol%, or any two of those values ​​within any range (e.g., 0.5 mol% to 1.5 mol%, 2.5 mol% to 4.0 mol%, etc.). The glass composition may be substantially free of TiO2.

[0077] In an embodiment, the glass composition comprises SiO2 in an amount ranging from 65 mol% to 75 mol%, Al2O3 in an amount ranging from 8 mol% to 14 mol%, Na2O in an amount ranging from 12 mol% to 17 mol%, K2O in an amount ranging from greater than 0 mol% to 0.2 mol%, and MgO in an amount ranging from 1.5 mol% to 6.0 mol%. Optionally, SnO2 may be included in an amount otherwise disclosed herein.

[0078] As mentioned, substrate 12 may have a glass-ceramic composition. The glass-ceramic is produced by controlled crystallization of glass. In these embodiments, the glass-ceramic has a crystallinity of about 30% to about 90%. Non-limiting examples of usable glass-ceramic systems include Li2O×Al2O3×nSiO2 (e.g., LAS system glass-ceramic), MgO×Al2O3×nSiO2 (e.g., MAS system glass-ceramic), and ZnO×Al2O3×nSiO2 (e.g., ZAS system glass-ceramic).

[0079] In an embodiment, when the substrate 12 has a glass composition or a glass-ceramic composition, the substrate 12 includes one or more compressive stress regions. The one or more compressive stress regions can be imparted by methods known in the art, such as thermal tempering or ion exchange.

[0080] As mentioned, substrate 12 may have a polymer composition. Suitable examples include poly(methyl methacrylate) (PMMA) and polycarbonate. The list is not intended to be exhaustive.

[0081] The substrate 12 further includes a substrate thickness 18. The substrate thickness 18 is measured perpendicular to the main surface 16. A micrometer can be used to determine the substrate thickness 18. In an embodiment, the substrate thickness 18 is in the range of 30 μm to 3.1 mm. For example, the substrate thickness 18 may be 30 μm, 50 μm, 100 μm, 200 μm, 300 μm, 400 μm, 500 μm, 600 μm, 700 μm, 800 μm, 900 μm, 1.0 mm, 1.2 mm, 1.4 mm, 1.6 mm, 1.8 mm, 2.0 mm, 2.2 mm, 2.4 mm, 2.6 mm, 2.8 mm, 3.0 mm, 3.1 mm, or any two of those values ​​within any range (e.g., 300 μm to 1.3 mm, 1.0 mm to 2.0 mm, etc.). The substrate thickness 18 may be less than 30 μm or greater than 3.1 mm.

[0082] The multilayer antireflective coating 14 comprises N double layers 20. In an embodiment, N is an integer ranging from 2 to 13. For example, N can be 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, or any range defined by any two of those values ​​(e.g., 2 to 5, 3 to 9, etc.). The value of N can be greater than 13.

[0083] Each bilayer 20 includes a high refractive index layer (HIL) 22 of a high refractive index material and a low refractive index layer (LIL) 24 of a low refractive index material. The low refractive index layer 24 is disposed on the high refractive index layer 22 and is farther from the main surface 16 of the substrate 12 than the high refractive index layer 22. For each bilayer 20, the high refractive index layer 22 is disposed first, and then the low refractive index layer 24 is disposed on the high refractive index layer 22.

[0084] The high-refractive-index layer 22 exhibits the HIL refractive index (n). The low-refractive-index layer 24 exhibits the LIL refractive index (n). The reference point for the corresponding refractive indices is electromagnetic radiation with a wavelength of 550 nm. For each of the N bilayers 20, the LIL refractive index (n) is less than the HIL refractive index (n). The LIL refractive index (n) from one of the N bilayers 20 may differ from the LIL refractive index (n) of any other one of the N bilayers 20. The HIL refractive index (n) from one of the N bilayers 20 may differ from the HIL refractive index (n) of any other one of the N bilayers 20.

[0085] In the implementation, the HIL refractive index (n) is in the range of 1.7 to 2.8. For example, the HIL refractive index (n) may be 1.7, 1.8, 1.9, 2.0, 2.1, 2.2, 2.3, 2.4, 2.5, 2.6, 2.7, 2.8, or any two of those values ​​within any range (e.g., 2.4 to 2.8, 1.9 to 2.6, etc.). In the implementation, the LIL refractive index (n) is in the range of 1.30 to 2.10. For example, the LIL refractive index (n) may be 1.3, 1.4, 1.5, 1.6, 1.7, 1.8, 1.9, 2.0, 2.1, or any two of those values ​​within any range (e.g., 1.3 to 1.5, 1.5 to 1.8, 1.6 to 2.0, etc.). One or more of the HIL refractive index (n) and LIL refractive index (n) may be outside the specified range.

[0086] In the embodiment, at least one of the N bilayers 20 is a high refractive index material comprising TiNbO. x And one or more of VON or made therefrom. Most N-numbered bilayer 20 high refractive index materials may include TiNbO x And one or more of VON or made therefrom. All N-numbered bilayer 20 high refractive index materials may include TiNbO x VON and SiN y One or more of these, or made from them. For example, the high refractive index material TiNbO x The HIL refractive indices (n) of SiN and VON are approximately 2.580 and 2.305, respectively, but vary with composition. y The refractive index (n) can be about 2.060, but it varies with the composition.

[0087] In the embodiment, at least one of the N bilayers 20 is a high refractive index material comprising TiNbO. x Or it may be made from it. Most N-number bilayer 20 high refractive index materials may include TiNbO x Or it may be made from it. All N-number bilayer 20 high-refractive-index materials may include TiNbO x Or made from it.

[0088] In one embodiment, the high refractive index material of at least one of the N number of bilayers 20 comprises a metal dispersed in a ceramic matrix. The high refractive index material of most of the N number of bilayers 20 may comprise a metal dispersed in a ceramic matrix. The high refractive index material of all N number of bilayers 20 may comprise a metal dispersed in a ceramic matrix.

[0089] In the implementation scheme, at least one of the N bilayers 20 comprises a low-refractive-index material including SiO2, MgF2, YF3, and SiN. y One or more of the following: , and YbF3. Most N-number bilayer 20 low-refractive-index materials may include SiO2, MgF2, YF3, SiN... y One or more of, and YbF3, or made therefrom. All N-numbered bilayer 20 low-refractive-index materials may include SiO2, MgF2, YF3, SiN... y One or more of YbF3, or made therefrom.

[0090] In the implementation scheme, the high refractive index material of the high refractive index layer 22 of one of the N number of bilayers 20 is the low refractive index material of the low refractive index layer 24 of the other N number of bilayers 20. An example of such a material is SiN. y As mentioned, for any particular double layer 20 of N double layers 20, the LIL refractive index (n) only needs to be less than the HIL refractive index (n). The LIL refractive index (n) of one of the N double layers 20 can be greater than the HIL refractive index (n) of the other of the N double layers 20. The HIL refractive index (n) of one of the N double layers 20 can be less than the LIL refractive index (n) of the other of the N double layers 20. Therefore, in the embodiment, SiN y It is a high-refractive-index material of the high-refractive-index layer 22, which is one of N double layers 20, and SiN y It is a low-refractive-index material of the low-refractive-index layer 24 of the other of the N double layers 20.

[0091] The high-refractive-index layer 22 exhibits HIL resistivity (ρ) greater than or equal to 1.0 Ω·cm, greater than 2.0 Ω·cm, greater than 3.0 Ω·cm, or even greater than 4.0 Ω·cm. For example, the HIL resistivity (ρ) can be 1.0 Ω·cm, 1.1 Ω·cm, 1.2 Ω·cm, 1.3 Ω·cm, 1.4 Ω·cm, 1.5 Ω·cm, 1.6 Ω·cm, 1.7 Ω·cm, 1.8 Ω·cm, 1.9 Ω·cm, 2.0 Ω·cm, 2.1 Ω·cm, 2.2 Ω·cm, 2.3 Ω·cm, 2.4 Ω·cm, 2.5 Ω·cm, 2.6 Ω·cm, 2.7 Ω·cm, 2.8 Ω·cm, 2.9 Ω·cm, 3.0 Ω·cm, 3.1 Ω·cm, 3.2 Ω·cm, 3.3 Ω·cm, ... 3.4 Ω·cm, 3.5 Ω·cm, 3.6 Ω·cm, 3.7 Ω·cm, 3.8 Ω·cm, 3.9 Ω·cm, 4.0 Ω·cm, 4.1 Ω·cm, 4.2 Ω·cm, 4.3 Ω·cm, 4.4 Ω·cm, 4.5 Ω·cm, 4.6 Ω·cm, 4.7 Ω·cm, 4.8 Ω·cm, 4.9 Ω·cm, 5.0 Ω·cm, or any two of those values ​​within any range (e.g., 1.0 Ω·cm to 4.0 Ω·cm, 2.0 Ω·cm to 3.5 Ω·cm, 4.0 Ω·cm to 4.6 Ω·cm, etc.). For example, the high refractive index material TiNbO x The resistivity (ρ) of HIL can be approximately 4.3 Ω·cm, but varies with composition. The resistivity (ρ) discussed in this paper is determined according to ASTM D257.

[0092] The high refractive index layer 22 exhibits an HIL extinction coefficient (k) greater than or equal to 0.15, greater than or equal to 0.20, greater than or equal to 0.25, or even greater than or equal to 0.30 for electromagnetic radiation with a wavelength of 500 nm. For example, the HIL extinction coefficient (k) for electromagnetic radiation with a wavelength of 500 nm can be 0.15, 0.16, 0.17, 0.18, 0.19, 0.20, 0.21, 0.22, 0.23, 0.24, 0.25, 0.26, 0.27, 0.29, 0.30, 0.31, 0.32, 0.33, 0.34, 0.35, 0.36, 0.37, 0.39, 0.40, or any two of those values ​​within any range (e.g., 0.15 to 0.40, 0.25 to 0.35, etc.). For example, the high refractive index material TiNbO xThe extinction coefficients (k) of HIL for electromagnetic radiation with a wavelength of 500 nm for VON are approximately 0.325 and 0.238, respectively. For the purposes of this disclosure, the HIL extinction coefficient (k), HIL refractive index (n), and LIL refractive index (n) are determined, for example, using a spectral ellipsometer manufactured by JA Woollam Co. (Lincoln, Nebraska, USA), employing variable angle spectral ellipsography. Additional information on variable angle spectral ellipsography can be found in “Overview of Variable Angle Spectroscopic Ellipsometry (VASE), Part I: Basic Theory and Typical Applications,” Critical Reviews of Optical Science and Technology, Vol. 72, pp. 3-28, 1999.

[0093] In the implementation, at least one of the N bilayers 20 exhibits an HIL extinction coefficient (k) that varies by less than 0.2 across the entire wavelength range of 400 nm to 800 nm. Spectral elliptometry can be used to determine the HIL extinction coefficient (k) as a function of wavelength across the entire range. Minimum and maximum values ​​of the HIL extinction coefficient (k) can be determined. The difference between them can be calculated. For the dependence of the HIL extinction coefficient (k) on wavelength, differences of less than 0.2 show a relatively flat pattern.

[0094] Each of the N number of bilayers 20 has a high refractive index layer 22 with a high-internal-layer (HIL) thickness 26. The HIL thickness 26 is measured, for example, using a scanning electron microscope (SEM) perpendicular to the main surface 16 of the substrate 12. In one embodiment, the HIL thickness 26 of one or more of the N number of bilayers 20 is in the range of 10 nm to 80 nm. For example, the HIL thickness 26 may be 10 nm, 15 nm, 20 nm, 25 nm, 30 nm, 35 nm, 40 nm, 45 nm, 50 nm, 55 nm, 60 nm, 65 nm, 70 nm, 75 nm, 80 nm, or any range defined by any two of those values ​​(e.g., 25 nm to 70 nm, 30 nm to 55 nm, etc.). The HIL thickness 26 of any or all of the N number of bilayers 20 may be outside the specified range.

[0095] Each of the N number of bilayers 20 has a low-refractive-index layer 24 with a low-intensity interlayer (LIL) thickness 28. The LIL thickness 28 is measured, for example, using a scanning electron microscope (SEM) perpendicular to the main surface 16 of the substrate 12. In one embodiment, the LIL thickness 28 of one or more of the N number of bilayers 20 is in the range of 5 nm to 150 nm. In another embodiment, the LIL thickness 28 of each of the N number of bilayers 20 is in the range of 10 nm to 150 nm. For example, the LIL thickness 28 can be 5nm, 10nm, 15nm, 20nm, 25nm, 30nm, 35nm, 40nm, 45nm, 50nm, 55nm, 60nm, 65nm, 70nm, 75nm, 80nm, 85nm, 90nm, 95nm, 100nm, 105nm, 110nm, 115nm, 120nm, 125nm, 130nm, 135nm, 140nm, 145nm, 150nm, or any range of any two of those values ​​(e.g., 25nm to 70nm, 30nm to 55nm, etc.). The LIL thickness 28 of any or all N bilayers 20 can be outside the specified range.

[0096] The multilayer antireflective coating 14 has a coating thickness of 30. The coating thickness 30 is measured, for example, using an SEM perpendicular to the main surface 16 of the substrate 12. In embodiments, the coating thickness 30 is less than or equal to 450 nm, less than or equal to 350 nm, or even less than or equal to 250 nm. In embodiments, the coating thickness 30 is in the range of 200 nm to 450 nm. For example, the coating thickness 30 can be 200nm, 210nm, 220nm, 230nm, 240nm, 250nm, 260nm, 270nm, 280nm, 290nm, 300nm, 310nm, 320nm, 330nm, 340nm, 350nm, 360nm, 370nm, 380nm, 390nm, 400nm, 410nm, 420nm, 430nm, 440nm, 450nm, or any two of those values ​​within any range (e.g., 220nm to 300nm, 250nm to 400nm, etc.). The coating thickness 30 can be outside the specified range.

[0097] In one embodiment, the multilayer antireflective coating 14 further includes an initial low-refractive-index layer 32 of a low-refractive-index material. The initial low-refractive-index layer 32 is disposed on the main surface 16 of the substrate 12. The initial low-refractive-index layer 32 is sandwiched between the main surface 16 of the substrate 12 and N number of double layers 20. It is considered that the initial low-refractive-index layer 32 increases the adhesion of the multilayer antireflective coating 14 to the main surface 16 of the substrate 12, along with the N number of double layers 20. The low-refractive-index material used for the initial low-refractive-index layer 32 can be any of the aforementioned low-refractive-index materials, such as SiO2.

[0098] For visible electromagnetic radiation passing through the antireflective article at an incident angle perpendicular to the main surface 16 of the substrate 12, the antireflective article 10 exhibits an average transmittance in the range of 25% to 90%. For example, the average transmittance exhibited by the antireflective article 10 may be 25%, 30%, 35%, 39%, 40%, 45%, 50%, 52%, 55%, 60%, 65%, 70%, 75%, 80%, 85%, 90%, or any range defined by any two of those values ​​(e.g., 50% to 80%, 39% to 52%, etc.).

[0099] For visible electromagnetic radiation incident on the multilayer antireflective coating 14 at a 10-degree angle relative to the normal of the main surface 16 of the substrate 12, the antireflective article 10 exhibits an average 1-sided reflectivity of less than or equal to 1.0%, less than or equal to 0.80%, less than or equal to 0.60%, or even less than or equal to 0.40%. For example, the average 1-sided reflectance can be 0.25%, 0.26%, 0.27%, 0.28%, 0.29%, 0.30%, 0.31%, 0.32%, 0.33%, 0.34%, 0.35%, 0.36%, 0.37%, 0.38%, 0.39%, 0.40%, 0.45%, 0.50%, 0.55%, 0.60%, 0.65%, 0.70%, 0.75%, 0.80%, 0.85%, 0.90%, 0.95%, 1.0%, or any range of any two of those values ​​(e.g., 0.25% to 0.50%, 0.28% to 0.38%, etc.).

[0100] For the purposes of this disclosure, "visible electromagnetic radiation" refers to the entire wavelength range from 400 nm to 700 nm. Additionally, for the purposes of this disclosure, "transmittance" is the percentage of incident optical power at any given wavelength within the visible spectrum transmitted through the antireflective article 10. Therefore, "average transmittance" is the average of those wavelength-dependent values ​​across the entire visible spectrum. Furthermore, for the purposes of this disclosure, "reflectance" is the percentage of incident optical power at any given wavelength within the visible spectrum reflected from the antireflective article 10, oriented towards the incident optical power, by the multilayer antireflective coating 14. Therefore, "average reflectance" is the average of those wavelength-dependent values ​​across the entire visible spectrum. When measured on only one side having the multilayer antireflective coating 14 (e.g., when reflections are removed from the other side of the antireflective article 10, such as by using a refractive index matching oil coupled to the other side of the absorber, or other known methods), reflectance is measured as unilateral (or first-side) reflectance. A suitable interval between the average transmittance and average unilateral reflectance measurements is 5 nm. Transmission and reflectance spectra can be collected using a UV / visible spectrophotometer, following the measurement rules of ISO 15368.

[0101] For visible electromagnetic radiation passing through the antireflective article at an angle of incidence perpendicular to the main surface 16 of the substrate 12, the antireflective article 10 exhibits a transmitted color characterized by the CIELAB color space of the International Commission on Illumination. In an embodiment, the transmitted color is characterized by a CIELAB color space having an L* value in the range of 60 to 85, an a* value in the range of 0 to 5.0, and a b* value in the range of 0 to 8.0. For example, the L* value may be 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, 80, 81, 82, 83, 84, 85, or any two of those values ​​within any range (e.g., 65 to 75, 70 to 76, etc.). For example, the a* value can be 0, 0.2, 0.4, 0.6, 0.8, 1.0, 1.2, 1.4, 1.6, 1.8, 2.0, 2.2, 2.4, 2.6, 2.8, 3.0, 3.2, 3.4, 3.6, 3.8, 4.0, 4.2, 4.4, 4.6, 4.8, 5.0, or any range of any two of those values ​​(e.g., 2.0 to 4.0, 2.3 to 3.4, etc.). For example, the b* value can be 0, 0.2, 0.4, 0.6, 0.8, 1.0, 1.2, 1.4, 1.6, 1.8, 2.0, 2.2, 2.4, 2.6, 2.8, 3.0, 3.2, 3.4, 3.6, 3.8, 4.0, 4.2, 4.4, 4.6, 4.8, 5.0, 5.2, 5.4, 5.6, 5.8, 6.0, 6.2, 6.4, 6.6, 6.8, 7.0, 7.2, 7.4, 7.6, 7.8, 8.0, or any two of those values ​​within any range (e.g., 4.0 to 7.0, 4.4 to 6.8, etc.). Transmitted color can be characterized using the CIELAB color space outside those ranges. Transmitted color can be determined using a spectrophotometer with a D65 luminescent material.

[0102] For visible electromagnetic radiation incident on the multilayer antireflective coating 14 at an angle of incidence 10 degrees away from the normal of the main surface 16 of the substrate 12, the antireflective article 10 exhibits a reflected color characterized by the CIELAB color space. In an embodiment, the reflected color is characterized by a CIELAB color space having an L* value in the range of >0 to 6.0, an a* value in the range of -5.0 to 0, and a b* value in the range of -5.0 to 0. For example, the L* value may be >0, 0.2, 0.4, 0.6, 0.8, 1.0, 1.2, 1.4, 1.6, 1.8, 2.0, 2.2, 2.4, 2.6, 2.8, 2.0, 3.2, 3.4, 3.6, 3.8, 4.0, 5.2, 5.4, 5.6, 5.8, 6.0, or any two of those values ​​within any range (e.g., 2.0 to 4.0, 2.4 to 3.8, etc.). For example, a* can be -5.0, -4.8, -4.6, -4.4, -4.2, -4.0, -3.8, -3.6, -3.4, -3.2, -3.0, -2.8, -2.6, -2.4, -2.2, -2.0, -1.8, -1.6, -1.4, -1.2, -1.0, -0.8, -0.6, -0.4, -0.2, 0, or any range of any two of those values ​​(e.g., -3.2 to -0.6, -2.8 to -1.0, etc.). For example, b* can be -5.0, -4.8, -4.6, -4.4, -4.2, -4.0, -3.8, -3.6, -3.4, -3.2, -3.0, -2.8, -2.6, -2.4, -2.2, -2.0, -1.8, -1.6, -1.4, -1.2, -1.0, -0.8, -0.6, -0.4, -0.2, 0, or any two of those values ​​within any range (e.g., -4.0 to -1.4, -3.6 to -2.0, etc.). Reflected colors can be characterized using the CIELAB color space outside those ranges. Reflected colors can be determined using a spectrophotometer with a D65 luminescent material.

[0103] The antireflective article 10 exhibits a hardness measured by a Berkovich nanoindentation test at an indentation depth of approximately 100 nm in the multilayer antireflective coating 14. In embodiments, the hardness is greater than or equal to 5.0 GPa, greater than or equal to 6.0 GPa, greater than or equal to 6.5 GPa, greater than or equal to 7.0 GPa, greater than or equal to 7.5 GPa, or even greater than or equal to 8.0 GPa. For example, the hardness can be 5.0 GPa, 5.2 GPa, 5.4 GPa, 5.6 GPa, 5.8 GPa, 6.0 GPa, 6.2 GPa, 6.4 GPa, 6.5 GPa, 6.6 GPa, 6.8 GPa, 7.0 GPa, 7.2 GPa, 7.4 GPa, 7.5 GPa, 7.6 GPa, 7.8 GPa, 8.0 GPa, or any range of any two of those values ​​(e.g., 6.0 GPa to 8.0 GPa, 6.6 GPa to 7.4 GPa, etc.).

[0104] For the purposes of this disclosure, the Berkovich nanoindentation test involves using a diamond Berkovich indenter to indent the antireflective article 10 on one side of the multilayer antireflective coating 14 to form an indentation depth ranging from about 50 nm to about 1000 nm (or a coating thickness of 30, whichever is less) and measuring the hardness of this indentation at various points along the entire range of indentation depth, along designated sections of this indentation depth (e.g., in a depth range of about 100 nm to about 500 nm), or at specific indentation depths (e.g., a depth of 100 nm, a depth of 500 nm, etc.), typically using the methods described below: Oliver, WC and Pharr, GM, “An improved technique for determining hardness and elastic modulus using load and displacement sensing indentation experiments”, J. Mater. Res, Vol. 7, No. 6, 1992, 1564-1583; and Oliver, WC and Pharr, GM, “Measurement of hardness and elastic Modulus by instrumented indentation: Advances inunderstanding and refinements to methodology, J. Mater. Res., Vol. 19, No. 1, 2004, 3-20. When hardness is measured in an indentation depth range (e.g., in a depth range of about 100 nm to about 500 nm), the result can be reported as the maximum hardness within the specified range, where the maximum value is selected from the measurement obtained at each depth within the range. As used herein, "hardness" and "maximum hardness" both mean the hardness value as measured, rather than the average of the hardness values. Similarly, when hardness is measured at an indentation depth, a hardness value obtained from the Berkovich nanoindentation test is given for that specific indentation depth.

[0105] Typically, in nanoindentation measurement methods used for optical film structures that are harder than the underlying substrate 12 (such as by using a Berkovich indenter), the measured hardness may appear to initially increase due to the presence of plastic regions at shallow indentation depths, then increase further at deeper indentation depths and reach a maximum or plateau. Subsequently, due to the effect of the underlying substrate 12, the hardness begins to decrease even at deeper indentation depths. The same effect can be observed when using a substrate 12 with increased hardness compared to a coating; however, due to the effect of the underlying substrate 12, the hardness increases at deeper indentation depths.

[0106] A range of indentation depths and hardness values ​​at certain indentation depths can be selected to identify the specific hardness response of the multilayer antireflective coating 14 and its layers described herein without the effect of the underlying substrate 12. When the hardness of the multilayer antireflective coating 14 disposed on the substrate 12 is measured using a Berkovich indenter, the region of permanent deformation (plastic region) of the material is associated with the material's hardness. During indentation, the elastic stress field extends far beyond this region of permanent deformation. As the indentation depth increases, the apparent hardness and modulus are affected by the interaction of the stress field with the substrate 12. The influence of the substrate 12 on hardness occurs at deeper indentation depths (typically greater than about 10% of the thickness of the multilayer antireflective coating 14 or its layers). Furthermore, a further complicating factor is that the hardness response utilizes a certain minimum load to exhibit full plasticity during indentation. Before reaching this minimum load, the hardness generally tends to increase.

[0107] At smaller indentation depths (also known as small loads) (e.g., up to about 50 nm), the apparent hardness of the material appears to increase sharply with indentation depth. This small range of indentation depths does not represent a true indicator of hardness; rather, it reflects the development of the aforementioned plastic region, which is related to the finite radius of curvature of the indenter. At medium indentation depths, the apparent hardness approaches its maximum. At deeper indentation depths, the effect of the substrate 12 becomes more pronounced with increasing indentation depth. Once the indentation depth exceeds the coating thickness 30, or about 30% of the layer thickness, the hardness may begin to decrease sharply.

[0108] The antireflective article 10 exhibits an elastic modulus measured by a Berkovich nanoindentation test at an indentation depth of approximately 100 nm in the multilayer antireflective coating 14. In embodiments, the elastic modulus is greater than or equal to 60 GPa, greater than or equal to 70 GPa, or even greater than or equal to 75 GPa. For example, the elastic modulus can be 60 GPa, 62 GPa, 64 GPa, 66 GPa, 68 GPa, 70 GPa, 72 GPa, 74 GPa, 76 GPa, 78 GPa, 80 GPa, 82 GPa, 84 GPa, or any two of those values ​​within any range (e.g., 60 GPa to 84 GPa, 70 GPa to 80 GPa, etc.). The elastic modulus can be less than 60 GPa.

[0109] In the embodiment, the antireflective article 10 exhibits a failure stress greater than 1500 MPa. For example, the failure stress exhibited by the article may be greater than 1600 MPa, greater than 1700 MPa, greater than 1800 MPa, or even greater than 1900 MPa. The failure stress exhibited by the article may be 1500 MPa, 1525 MPa, 1550 MPa, 1575 MPa, 1600 MPa, 1625 MPa, 1650 MPa, 1675 MPa, 1700 MPa, 1725 MPa, 1750 MPa, 1775 MPa, 1800 MPa, 1825 MPa, 1850 MPa, 1875 MPa, 1900 MPa, 1950 MPa, 2000 MPa, or any range defined by any two of those values ​​(e.g., 1500 MPa to 1900 MPa, 1800 MPa to 1875 MPa, etc.). The article exhibits a failure stress of less than 1500 MPa. In the embodiments, the article exhibits a failure strain greater than 1.5%, greater than 1.8%, or even greater than 2.0%. For example, the article exhibits a failure strain of 1.5%, 1.6%, 1.7%, 1.8%, 1.9%, 2.0%, 2.1%, 2.2%, 2.3%, 2.4%, 2.5%, or any two of those values ​​within any range (e.g., 1.8% to 2.0%, 1.5% to 2.0%, etc.). The article exhibits a failure strain of less than 1.5%. “Failure stress” and “failure strain” are determined according to ASTM C1499-19 entitled Standard Test Method for Monotonic Equibiaxial Flexural Strength of Advanced Ceramics at Ambient Temperature. A substrate thickness of 0.8 mm is used. Generally, when testing according to ASTM C1499-19, the antireflective article 10 is placed between a load ring and a support ring. The diameter of the support ring is larger than the diameter of the load ring. A load is then applied to the load ring until the breaking load (the load that causes the antireflective article 10 to break) is determined. Based on the breaking load, the failure stress can be determined. After multiple tests (each using a different sample), the failure probability as a function of the failure stress can be determined. This is sometimes referred to as the Weibull distribution, from which the failure stress leading to a 63.5% failure probability can be determined. The 63.5% failure probability is sometimes referred to as the characteristic strength. The "failure stress" value provided in this document represents a 63.5% failure probability. The "failure strain" is calculated based on the elastic modulus and Poisson's ratio.

[0110] Now for reference Figure 3The anti-reflective article 10 can be incorporated as a component of the touchscreen display 100. The touchscreen display 100 includes an electronic display 102, a touchscreen layer 104, and the anti-reflective article 10. The touchscreen layer 104 is disposed between the anti-reflective article 10 and the electronic display 102. The anti-reflective article 10 is positioned above the electronic display 102 such that visible electromagnetic radiation transmitted from the electronic display 102 is at least partially transmitted through the anti-reflective article 10 to the external environment 106. The touchscreen display 100 can be incorporated into a vehicle, providing a concealed panel aesthetic.

[0111] Now for reference Figure 4 This document discloses a method 200 for manufacturing an antireflective article 10. Method 200 includes a co-sputtering step 202. The co-sputtering step 202 includes simultaneously sputtering a first source material 204 comprising Ti and a source material comprising NbO in the presence of O2 and Ar. x The second source material 206. The co-sputtering step 202 forms at least one high-refractive-index layer 22 of an N-number of bilayers 20. In an embodiment, the high-refractive-index layer 22 of at least one of the N-number of bilayers 20 of the antireflective article 10 is formed by co-sputtering at least two different source materials of the high-refractive-index material – for example, a first source material 204 and a second source material 206. The high-refractive-index layer 22 of each of the N-number of bilayers 20 can be formed by co-sputtering step 202. In an embodiment, the high-refractive-index layer 22 of each of the N-number of bilayers 20 of the antireflective article 10 is formed by co-sputtering at least two different source materials of the high-refractive-index material – for example, a first source material 204 and a second source material 206. In an embodiment, the at least two different source materials include Ti metal and NbO. x Ceramics. Emphasis should be placed on TiO₂ produced using co-sputtering as the source material. x and NbO x The resulting layer differs in composition from Ti metal and NbO used as source materials in co-sputtering. x To form a layer. Co-sputtering Ti metal and NbOx ceramic produces a layer with Ti metal dispersed in a ceramic matrix. Co-sputtering TiO x and NbO x No Ti metal is dispersed in the ceramic matrix. Different compositions produce different optical and electrical properties. Specifically, Ti metal and NbO are co-sputtered as source materials. x The resulting layer exhibits an extinction coefficient (k) that varies relatively flatly with wavelength across the visible range. In contrast, TiO2, with co-sputtering as the source material... x and NbO xThe resulting layer can exhibit an extinction coefficient (k) that varies with wavelength across the entire range of 400 nm to 600 nm, from a low value of less than 0.01 at 400 nm to an exponentially decreasing value.

[0112] The antireflective article 10 addresses the problems mentioned in the background art, as well as other issues, in several ways. Specifically, the antireflective article 10 achieves reduced transmission and reflection while maintaining touch capability using a smaller number of N double layers 20. The number of N double layers 20 discussed herein is much lower than the number of double layers 20 attempted with other materials (e.g., more than 15 double layers 20). The smaller number of N double layers 20 allows the antireflective article 10 to be formed using existing sputtering equipment. Therefore, the total cost of manufacturing the antireflective article 10 is much lower than other attempts. The resistivity of the high refractive index layer 22 makes the antireflective article 10 compatible with touchscreen functionality. In some cases, the high refractive index material is TiNbO. x The HIL resistivity (ρ) exhibits properties suitable for touchscreen functionality, and the HIL extinction coefficient (k) and HIL refractive index (n) are suitable for anti-reflection through destructive interference. The transmittance and reflectance exhibited by the anti-reflective article 10 make it suitable for concealed panel aesthetics.

[0113] Example:

[0114] Example 1 – For Example 1, in the presence of O2 and Ar, a first source material including Ti and a source material including NbO were used. x The second source material, through the co-sputtering step of this disclosure, is the high refractive index material TiNbO. x A layer is applied to the main surface of the substrate. The high refractive index material TiNbO is determined to vary with electromagnetic radiation wavelengths from 300 nm to 800 nm. x The refractive index (n) and extinction coefficient (k) of the layer. Then, the results are... Figure 5 Plot the reproduced graph. As the graph shows, the refractive index ranges between 2.5 and 2.7 throughout the visible spectrum, while the extinction coefficient (k) is relatively flat throughout the visible spectrum, varying slightly between 0.25 and 0.40.

[0115] Example 2 – For Example 2, a low-refractive-index SiO2 layer was applied to the main surface of a substrate by reactive sputtering. The refractive index (n) and extinction coefficient (k) of the low-refractive-index SiO2 layer as a function of electromagnetic radiation wavelengths from 300 nm to 800 nm were determined. The results were then presented in… Figure 6 Plot the reproduced graph. As the graph shows, the refractive index (n) is in the range of 1.455 to 1.475 throughout the visible spectrum, while the extinction coefficient (k) is 0 throughout the visible spectrum.

[0116] Example 3 – For Example 3, high or low refractive index material (depending on the specific case) SiN y The layer was applied to the main surface of the substrate via reactive sputtering. The SiN layer was determined as a function of electromagnetic radiation wavelengths from 300 nm to 800 nm. y The refractive index (n) and extinction coefficient (k) of the layer. Then, the results are... Figure 7 Plot the reproduced graph. As the graph shows, the refractive index (n) is in the range of 2.02 to 2.12 throughout the visible spectrum, while the extinction coefficient (k) is 0 throughout the visible spectrum.

[0117] Examples 4-10 – For Examples 4-10, the high refractive index material TiNbO x The layer is applied to the main surface of the substrate via a co-sponging process as disclosed in this disclosure. For each embodiment, numerous variables are adjusted and considered, including NbO. x The loading percentage of Ti source material, the volumetric flow rates of Ar and O2 (and therefore the calculated volume percentage of O2), voltage, base pressure (“BaseP”), and process pressure (“ProcessP”) were also considered. Constants for all embodiments were 5 kW power, 50 kHz frequency, 1 m / min speed, and single-pass. After forming the layers for each embodiment, various properties were measured – specifically, thickness, refractive index (n) as a function of wavelength, extinction coefficient (k) as a function of wavelength, and resistivity (ρ). The variables and measured properties for each embodiment are illustrated in Table 1 below.

[0118]

[0119]

[0120] As shown in Table 1, TiNbO from all Examples 4-10 x The layer exhibits a refractive index (n) suitable for forming a multilayer antireflective coating that relies on phase cancellation interference, an extinction coefficient (k) suitable for reducing the transmittance of visible light through the layer, and a resistivity (ρ) suitable for compatibility with adjacent touchscreen layers.

[0121] Now see Figure 8 The refractive index (n) as a function of wavelength for each of Examples 4-10 is listed and plotted. As the charts show, the refractive index (n) generally decreases as the loading percentage Ti increases. In all cases, the refractive index (n) remains in the range of 2.5 to 2.7 throughout the entire visible range of electromagnetic radiation.

[0122] Now see Figure 9The extinction coefficient (k) as a function of wavelength for each of Examples 4-10 is listed and plotted. Unlike the refractive index (n), the graphs do not show a clear dependence of the extinction coefficient (k) on the percentage of Ti loading. In any case, in all cases, the extinction coefficient (k) remains in the range of about 0.23 to about 0.37 throughout the entire visible electromagnetic radiation range.

[0123] Comparative Examples 11-32 – For Comparative Examples 11-32, the high refractive index material TiNbO x The layer is applied to the main surface of the substrate via a co-sponging process as disclosed in this disclosure. For each embodiment, numerous variables are adjusted and considered, including NbO. x The loading percentage of Ti source material, the volumetric flow rates of Ar and O2 (and therefore the calculated volume percentage of O2), voltage, reference pressure, and process pressure were all measured. Constants for all embodiments were 5 kW power, 50 kHz frequency, 1 m / min speed, and single-pass. After forming the layers for each embodiment, various properties were measured – specifically, thickness, refractive index (n) at 550 nm wavelength, extinction coefficient (k) at 400 nm and 500 nm wavelengths, and resistivity (ρ). The variables and measured properties for each embodiment are illustrated in Table 2 below.

[0124]

[0125]

[0126] As shown in Table 2, the TiNbO of Comparative Examples 12, 13, 15-28, 30, and 31 are compared. x The layer is unsuitable for the purposes of this disclosure, at least because it exhibits a resistivity (ρ) of less than 1.0 Ω·cm. The remaining comparative embodiments 11, 14, 29, and 32 are unsuitable for the purposes of this disclosure, at least because they exhibit an extinction coefficient (k) of less than 0.300 at 400 nm. Only comparative embodiments 12, 13, and 25 are unsuitable for the purposes of this disclosure because they exhibit a resistivity (ρ) of less than 1.0 Ω·cm and an extinction coefficient (k) of less than 0.300 at 400 nm.

[0127] Compared to Comparative Examples 11-32, Examples 4-10 show the presence of TiNbO formed by co-sponging. x The processing window of the layer allows for the implementation of the properties required by this disclosure. For example, the loading percentage of Ti source material can be in the range of 25% to 35%, the volumetric flow rate of Ar can be in the range of 150 sccm to 500 sccm, and the volumetric flow rate of O2 can be in the range of 8 sccm to 12 sccm. The processing conditions of Example 4 are exemplary.

[0128] Examples 33-35 – For each Example 33-35, an antireflective article according to the present disclosure is formed. More specifically, for each example, a substrate having a glass composition and a thickness of 0.55 mm is utilized. A multilayer antireflective coating is disposed on the main surface of the substrate. The multilayer antireflective coating comprises an initial low-refractive-index layer of a low-refractive-index material (SiO2) disposed on the main surface of the substrate by sputtering. The thickness of the initial low-refractive-index layer is different for each example and is illustrated in Table 3 below. Then, N (especially 3) double layers of a high-refractive-index layer of a high-refractive-index material and a low-refractive-index layer of a low-refractive-index material are added on the initial low-refractive-index layer by sputtering. The thickness of the high-refractive-index layer and the low-refractive-index layer in each example, and the composition of the high-refractive-index material and the low-refractive-index material, are illustrated in Table 3 below. At least one high-refractive-index layer in each example is incorporated into TiNbO. x As a high refractive index material, a high refractive index layer is formed using co-spongeing. At least one low refractive index layer in each embodiment is incorporated into SiO2 as a low refractive index material. Example 34 incorporates SiN. y A high-refractive-index material as a high-refractive-index layer and a low-refractive-index material as a low-refractive-index layer. Images of the anti-reflective articles of each embodiment are captured. Images are in Figure 10 Reproduced in the middle. The anti-reflective article of each embodiment is shown in gray / black color.

[0129]

[0130] The antireflective article of each embodiment was then evaluated to determine its corresponding average transmittance through it in the entire visible spectrum, transmitted color, its corresponding first-side (at the multilayer antireflective coating) average 1-side reflectance in the entire visible spectrum, reflected color, resistance of the multilayer antireflective coating, whether the antireflective article is compatible with touchscreen functionality, and whether the multilayer antireflective coating is durable. The results are illustrated in Table 4 below.

[0131]

[0132] As shown in Table 4, the antireflective articles of each embodiment exhibit an average transmittance in the visible spectrum ranging from 40% to 50%, an average lateral reflectance in the visible spectrum less than 0.40, and relatively neutral transmittance and reflectance colors. These properties make the antireflective articles suitable for concealed panel aesthetics. Furthermore, the antireflective articles of each embodiment exhibit sufficient resistance for touchscreen compatibility. The transmittance and reflectance spectra of Examples 33-35 are respectively in... Figure 11-13 It reappeared in the middle.

[0133] The hardness and elastic modulus of the antireflective article of Example 34 were determined by Berkovich nanoindentation. The results are listed in a table. A graph of the results is shown in... Figure 14The results were reproduced in the middle. As shown in the figure, the elastic modulus at a depth of 100 nm is between 75 GPa and 80 GPa, while the hardness is about 70 GPa.

[0134] Examples 36-38 – For Examples 36-38, antireflective articles of this disclosure are formed. Each antireflective article comprises a substrate of a glass composition, and the substrate has been subjected to ion exchange to impart regional compressive stress continuous with its main surface. Various tests are then performed on the antireflective articles. Specifically, Berkovich nanoindentation tests are performed on the antireflective articles to determine hardness and elastic modulus.

[0135] In addition, antireflective articles were evaluated to determine their compressive stress levels. Compressive stress can be measured using a surface stress meter (FSM), such as the FSM-6000 manufactured by Orihara Industrial Co., Ltd. (Japan). Surface stress measurement relies on the accurate measurement of the stress optical coefficient (SOC), which is related to the birefringence of the glass. SOC is measured using methods known in the art, such as the fiber method and four-point bending method, as well as the bulk cylinder method, all described in ASTM C770-98 (2013), entitled "Standard Test Method for Measurement of Glass Stress-Optical Coefficient," the contents of which are incorporated herein by reference in their entirety. As used herein, CS can refer to "maximum compressive stress," i.e., the highest compressive stress value measured within the compressive stress layer.

[0136] In addition, antireflective materials were evaluated to determine the surface roughness (Ra) of the exposed surfaces. Surface roughness (Ra) a The value of is defined as the arithmetic mean of the differences between the local surface height and the average surface height, and can be described by the following formula:

[0137]

[0138] Where y i It is the local surface height relative to the average surface height, wherein the surface roughness (R) of at least three sample regions (n) of approximately 100 μm × 100 μm is defined. a )Measure and average. Surface roughness (R) a ) Surface profilometers provided by Zygo Corp. can be used for measurement.

[0139] In addition, the average water contact angle of the exposed surface of the multilayer antireflective coating was tested. In one set of tests, the average water contact angle was determined according to ASTM D7490 after at least 400,000 cycles of coarse cotton cloth under a load of 7.5 N. In another set of tests, the average water contact angle was determined after 3,500 cycles of #0000 steel wool under a load of 1 kg, at 60 cycles / min and a stroke length of 25 mm.

[0140] The test results are reproduced in Table 5 below.

[0141]

[0142] Example 39 – For Example 39, several samples of the antireflective article of this disclosure were formed. The samples were then tested according to ASTM C1499 to determine the characteristic strength, for example, the stress with a failure probability of 63.2%. The characteristic strength was determined to be approximately 1490 MPa. The test results are reproduced graphically in… Figure 15 .

[0143] Example 40 – For Example 40, an antireflective article of this disclosure was formed. The antireflective article was then tested to determine the varying water contact angle after (i) the coarse cotton cloth test mentioned above in ASTM D7490, (ii) the “damp heat” test in which the article was held in a chamber at 85°C and 95% relative humidity for 500 hours, and (iii) the “thermal shock” test in which the article was subjected to alternating 30-minute cycles of cold temperature (-40°C) followed by hot temperature (95°C). The results are listed in Table 6 below.

[0144]

[0145] Example 40 – For Example 40, an antireflective article of this disclosure was formed. The antireflective article was then tested to determine the extent of peeling following surface damage. Specifically, damage traces were introduced into the exposed surface of the multilayer antireflective coating. Images of the damaged area were taken using an optical microscope at 50x and 200x magnification. Vaseline was then applied to the damaged area and soaked for 15 minutes. Images of the damaged area were again taken using an optical microscope at 50x and 200x magnification. The before and after images were then compared to determine whether contact with the Vaseline caused peeling of the multilayer antireflective coating. No significant peeling was detected. Images in Figure 16 It reappeared in the middle.

[0146] It will be apparent to those skilled in the art that various modifications and alterations can be made without departing from the spirit or scope of the invention.

Claims

1. An anti-reflective article, the anti-reflective article comprising: A substrate, the substrate including a main surface; and A multilayer antireflective coating is disposed on the main surface of the substrate, the multilayer antireflective coating comprising N double layers, each double layer comprising: HIL materials exhibiting (i) high refractive index (HIL) refractive index, (ii) HIL resistivity (ρ) and (iii) HIL extinction coefficient (k); and A low-refractive-index layer (LIL) of a low-refractive-index material is disposed above a high-refractive-index layer and is farther from the main surface than the high-refractive-index layer. For electromagnetic radiation with a wavelength of 550 nm, the LIL exhibits a refractive index lower than that of the high-refractive-index layer (HIL). The resistivity (ρ) of the HIL is greater than or equal to 1.0 Ω·cm. The HIL extinction coefficient (k) for electromagnetic radiation with a wavelength of 500 nm is greater than or equal to 0.

15. For visible electromagnetic radiation passing through the antireflective article at an incident angle perpendicular to the main surface, the antireflective article exhibits an average transmittance in the range of 25% to 90%, and For visible electromagnetic radiation incident on the multilayer antireflective coating at an angle of 10 degrees relative to the normal of the main surface, the antireflective article exhibits an average 1-sided reflectivity of less than or equal to 1.0%.

2. The antireflective article as claimed in claim 1, wherein... The substrate comprises a glass composition, a glass-ceramic composition, or a polymer composition.

3. The antireflective article as described in any one of claims 1-2, wherein The substrate has a thickness ranging from 30 μm to 3.1 mm, measured perpendicular to the main surface.

4. The antireflective article as described in claim 3, wherein... The thickness of the substrate is in the range of 300 μm to 1.3 mm.

5. The antireflective article as described in any one of claims 1-4, wherein N is an integer in the range of 2 to 13.

6. The antireflective article according to any one of claims 1-5, wherein The refractive index of the HIL is in the range of 1.7 to 2.

8.

7. The antireflective article as claimed in claim 6, wherein... The refractive index of the HIL is in the range of 2.4 to 2.

8.

8. The antireflective article according to any one of claims 1-7, wherein The refractive index of the LIL is in the range of 1.3 to 2.

1.

9. The antireflective article as claimed in claim 8, wherein... The refractive index of the LIL is in the range of 1.3 to 1.

5.

10. The antireflective article according to any one of claims 1-9, wherein The high-refractive-index material of at least one of the N number of bilayers comprises TiNbO x VON and SiN y One or more of them.

11. The antireflective article as claimed in claim 10, wherein... The high-refractive-index material of at least one of the N number of bilayers comprises TiNbO x .

12. The antireflective article according to any one of claims 1-11, wherein The high refractive index material of at least one of the N bilayers comprises a metal dispersed in a ceramic matrix.

13. The antireflective article according to any one of claims 1-12, wherein The low-refractive-index material of at least one of the N number of bilayers comprises SiO2, MgF2, YF3, SiN y One or more of YbF3.

14. The antireflective article according to any one of claims 1-13, wherein The high refractive index material of the high refractive index layer of one of the N number of bilayers is the low refractive index material of the low refractive index layer of the other of the N number of bilayers.

15. The antireflective article as claimed in claim 14, wherein... SiN y It is the high refractive index material of the high refractive index layer of one of the N number of bilayers, and SiN y It is the low-refractive-index material of the low-refractive-index layer of another of the N number of double layers.

16. The antireflective article according to any one of claims 1-15, wherein The resistivity (ρ) of the HIL is greater than or equal to 2.0 Ω·cm.

17. The antireflective article according to any one of claims 1-16, wherein The HIL extinction coefficient (k) for electromagnetic radiation with a wavelength of 500 nm is greater than or equal to 0.

30.

18. The antireflective article as claimed in any one of claims 1-17, wherein At least one of the N bilayers exhibits an extinction coefficient (k) of less than 0.2 across the entire wavelength range of 400 nm to 800 nm.

19. The antireflective article as claimed in any one of claims 1-18, wherein Each of the N number of bilayers has a high refractive index layer with a HIL thickness in the range of 10 nm to 80 nm.

20. The antireflective article as claimed in any one of claims 1-19, wherein Each of the N number of bilayers has a low refractive index layer with a LIL thickness ranging from 5 nm to 150 nm.

21. The antireflective article according to any one of claims 1-20, wherein The multilayer antireflective coating has a coating thickness of less than or equal to 450 nm, measured perpendicular to the main surface.

22. The antireflective article as claimed in any one of claims 1-21, wherein The multilayer antireflective coating further includes an initial low-refractive-index layer of low-refractive-index material located on the main surface of the substrate, the initial low-refractive-index layer being sandwiched between the main surface of the substrate and the N number of double layers.

23. The antireflective article as claimed in any one of claims 1-22, wherein The antireflective material exhibits an average transmittance in the range of 50% to 80%.

24. The antireflective article as claimed in any one of claims 1-22, wherein The antireflective material exhibits an average transmittance in the range of 39% to 52%.

25. The antireflective article as claimed in any one of claims 1-24, wherein For visible electromagnetic radiation passing through the antireflective article at an incident angle perpendicular to the main surface of the substrate, the antireflective article exhibits a transmitted color characterized by an L* value in the range of 60 to 85, an a* value in the range of 0 to 5.0, and a b* value in the range of 0 to 8.0, as characterized by the CIELAB color space.

26. The antireflective article as claimed in any one of claims 1-25, wherein For visible electromagnetic radiation incident on the multilayer antireflective coating at an angle of incidence 10 degrees away from the normal of the main surface of the substrate, the antireflective article exhibits a reflected color characterized by the CIELAB color space, having an L* value in the range of >0 to 6.0, an a* value in the range of -5.0 to 0, and a b* value in the range of -5.0 to 0.

27. The antireflective article as claimed in any one of claims 1-26, wherein The antireflective article exhibits (i) a hardness greater than or equal to 6.5 GPa as measured by Berkovich nanoindentation test at an indentation depth of approximately 100 nm in the multilayer antireflective coating and (ii) an elastic modulus greater than or equal to 60 GPa as measured by Berkovich nanoindentation test at an indentation depth of approximately 100 nm in the multilayer antireflective coating.

28. The antireflective article as claimed in any one of claims 1-27, wherein The anti-reflective product exhibits a failure stress greater than 1500 MPa.

29. The antireflective article as claimed in any one of claims 1-28, wherein The antireflective material exhibits a failure strain greater than 1.5%.

30. The antireflective article as claimed in any one of claims 1-29, wherein The high refractive index layer of at least one of the N number of bilayers is formed by co-sputtering the high refractive index material with at least two different source materials.

31. The antireflective article as claimed in claim 30, wherein... The at least two different source materials include Ti metal and NbO. x ceramics.

32. A touchscreen display, the touchscreen display comprising: Electronic displays; The anti-reflective article as described in any one of claims 1-31 is positioned above the electronic display such that visible electromagnetic radiation transmitted by the electronic display passes through the anti-reflective article at least partially and is transmitted to the external environment. and A touchscreen layer is disposed between the antireflective material and the electronic display.

33. A method for manufacturing an antireflective article as described in any one of claims 1-31, the method comprising: The co-sputtering step includes simultaneously sputtering a first source material containing Ti and a source material containing NbO in the presence of O2 and Ar. x The second source material, thereby forming the high refractive index layer of at least one of the N number of bilayers.

Images