Deadfront articles having multilayer optical structures and related methods

Abstract

Described herein are dead front assemblies configured to exhibit a variety of varying transmission and reflection performance attributes. The dead front assemblies described herein include a first ink layer, an intermediate layer, and a second ink layer. The intermediate layer is disposed between the first and second ink layers and is configured to reflect light transmitted through the first ink layer back through the first ink layer so that one or more colors of ink in the first ink layer are visible in reflected light. The second ink layer is configured to counteract deviations in light transmission that occur in the first ink layer so that the color of light transmitted through the dead front assembly is not perceptibly changed. The overlapping region of the first and second ink layers has opposite appearance attributes so that light output from a light source transmitted through the dead front assembly has a desired appearance.

Description

Description of Related Applications

[0001] This application claims the benefit of priority under 35 U.S.C. § 119 of U.S. Provisional Patent Application No. 63 / 411,963, filed September 30, 2022, the contents of which are relied upon and incorporated herein by reference in its entirety. [Technical Field]

[0002] SUMMARY The present disclosure relates to display articles with dead-front assemblies that exhibit improved color distortion performance, and related methods. [Background technology]

[0003] In various applications, including displays, it is desirable to have a display or functional surface that has a dead-front appearance, where the transition between the display and non-display areas is seamless. Dead-front technology may be used, for example, to hide the edges of a display panel or the like when the article is viewed through a cover surface (e.g., of a plastic or glass display cover material). From an aesthetic or design perspective, it is desirable to have a dead-front appearance so that when the display is off, the display and non-display areas are indistinguishable from one another, and the cover surface presents a unified appearance. Applications where a dead-front appearance is desirable include automotive interiors, including in-vehicle displays or touch-sensitive interfaces, as well as other applications in consumer portable or home electronic devices, including mobile devices and home appliances.

[0004] Existing deadfront technologies typically involve the application of a film or layer that reduces the overall light transmission of the entire assembly (e.g., including the display panel and cover material). The application of such existing films or layers can provide an article with a sufficiently low light transmission rate to conceal various components of the assembly while also providing a unified appearance by allowing the pattern exhibited by the article to blend with the surrounding materials (e.g., the article can be patterned to exhibit a wood grain or woven pattern in reflection). However, some existing assemblies may not be able to provide the desired appearance in reflection without significantly adversely affecting the article's light transmission performance. For example, some existing deadfront assemblies may alter the appearance of the image presented by the display panel due to the manner in which the layers absorb the light emitted by the display panel. Different portions of the layers may absorb the light emitted by the display differently, resulting in color distortions in the displayed image. Summary of the Invention [Problem to be solved by the invention]

[0005] Therefore, an alternative dead-front approach that provides a uniform or dead-front appearance in reflection with improved color distortion performance in transmission is desirable. [Means for solving the problem]

[0006] Aspect (1) of the present disclosure relates to a dead-front article comprising a substrate having a first major surface and a second major surface opposite the first major surface; and a dead-front assembly disposed on the second major surface, the dead-front assembly including: a first ink layer disposed proximate to the second major surface; an intermediate layer positioned such that the first ink layer is disposed between the intermediate layer and the second major surface; and a second ink layer positioned such that the intermediate layer is disposed between the second ink layer and the first ink layer, the intermediate layer exhibiting an average reflectance of 1.0% or greater over a wavelength range of 400 nm to 700 nm for light initially incident on the surface of the intermediate layer closest to the substrate; the first ink layer including a first plurality of regions; and the second ink layer including a second plurality of regions, each region of the second plurality of regions configured to suppress deviation of the appearance of overlapping regions of the first plurality of regions from a target optical appearance in transmission.

[0007] Aspect (2) of the present disclosure relates to the deadfront article according to aspect (1), wherein each region of the second plurality of regions has tristimulus X, Y, and Z values ​​according to the CIE 1931 color space calculated as a ratio of a target value to the tristimulus X, Y, and Z values ​​of an overlapping region of the first plurality of regions, and each of the target values ​​is greater than or equal to 0.30 and less than or equal to 0.50.

[0008] In the third aspect of the present disclosure, when light from a D65 light source is transmitted through a dead front article, the light has a maximum L of 50 or more and 80 or less. * The dead-front article according to embodiment (1) exhibits a value.

[0009] In the fourth aspect of the present disclosure, when light from a D65 light source is transmitted through a dead front article, the light has a maximum a value of -5 or more and 5 or less. * value and the maximum b between -5 and 5 * The dead-front article according to aspect (3) exhibits a value.

[0010] Aspect (5) of the present disclosure relates to a dead-front article according to any of aspects (3) to (4), wherein when light from a D65 light source is transmitted through the dead-front article, the light exhibits a maximum ΔE value, calculated using the CIE 76 formula, between two different positions on the dead-front article that is 5.0 or less.

[0011] A sixth aspect of the present disclosure relates to the dead-front article according to the fifth aspect, wherein the maximum ΔE value is 2.0 or less.

[0012] Aspect (7) of the present disclosure relates to a deadfront article according to any of aspects (1) to (6), wherein each overlapping pair of regions, including one of the first plurality of regions and one of the second plurality of regions, exhibits a tristimulus Y value of 0.3 or greater and 0.5 or less when light from a light source is transmitted through the deadfront assembly.

[0013] An embodiment (8) of the present disclosure relates to a deadfront article according to any one of embodiments (1) to (7), wherein the intermediate layer has a refractive index of 1.8 or more or 1.2 or less.

[0014] Aspect (9) of the present disclosure relates to a deadfront article according to any one of aspects (1) to (8), wherein the intermediate layer includes at least one of a clear ink, a white ink, or a gray ink.

[0015] A tenth aspect of the present disclosure relates to a deadfront article according to any one of the first to eighth aspects, wherein the intermediate layer comprises a metal layer.

[0016] An aspect (11) of the present disclosure relates to a dead-front article according to any of aspects (1) to (8), wherein the intermediate layer comprises a gap between the first ink layer and the second ink layer, and the second ink layer is disposed on a surface of a second substrate held in a fixed relationship relative to the substrate.

[0017] Aspect (12) of the present disclosure relates to a dead-front article according to any of aspects (1) to (8), wherein the intermediate layer has a refractive index of 1.8 or greater and comprises at least one of Nb2O5, Ta2O5, ZrO2, HfO2, Si3N4, SiON, YO3, TiO2, and a transparent conductive oxide, the first ink layer being disposed adjacent to a first surface of the intermediate layer that is adjacent to the substrate, and the second ink layer being disposed directly on the second surface of the intermediate layer.

[0018] Aspect (13) of the present disclosure relates to a deadfront article according to any of aspects (1) to (8), wherein the intermediate layer comprises a multilayer stack comprising alternating layers of one or more high refractive index materials and one or more low refractive index materials, the multilayer stack comprising 2 to 20 alternating layers, wherein the one or more low refractive index materials have a refractive index less than 1.6 at 550 nm and the one or more high refractive index materials have a refractive index greater than 1.6 at 550 nm.

[0019] Aspect (14) of the present disclosure relates to a deadfront article according to any of aspects (1) to (8), wherein the intermediate layer includes an electrochromic layer configured to change between a first light transmission state and a second light transmission state, and wherein the average transmittance of the intermediate layer over the wavelength range is lower in the first light transmission state.

[0020] Aspect (15) of the present disclosure relates to a dead-front article according to any of aspects (1) to (7), wherein the intermediate layer includes a second substrate and a reflective layer disposed on a surface of the second substrate adjacent to one of the first ink layer and the second ink layer, the first ink layer being disposed on a first surface of the second substrate adjacent to the substrate, and the second ink layer being disposed on a second surface of the second substrate.

[0021] Aspect (16) of the present disclosure provides a display assembly comprising: a substrate having a first major surface and a second major surface opposite the first major surface; a dead-front assembly disposed on the second major surface, the dead-front assembly including a first ink layer disposed proximate the second major surface, an intermediate layer positioned such that the first ink layer is disposed between the intermediate layer and the second major surface, and a second ink layer positioned such that the intermediate layer is disposed between the second ink layer and the first ink layer; and a light source, the dead-front assembly being disposed between the light source and the substrate. the light source is coupled to the substrate so as to be placed on the substrate, the light source being configured to emit light having an illumination spectrum spanning a wavelength range of 400 nm to 700 nm that initially strikes the intermediate layer, the first ink layer, and the second ink layer before transmitting through the substrate, the intermediate layer exhibiting an average reflectance of 1.0% or greater across the wavelength range for light that initially strikes a surface of the intermediate layer closest to the substrate, the first ink layer including a first plurality of regions and the second ink layer including a second plurality of regions, each region of the second plurality of regions having an L in transmission of 50 or greater and 80 or less when the light source emits light at a white point of the light source. * a value, greater than or equal to -5.0 and less than or equal to 5.0 * value, and b between -5.0 and 5.0 * The present invention relates to a display assembly configured to inhibit deviation of an appearance of an overlapping region of a first plurality of regions from a target optical appearance so as to indicate a value.

[0022] Aspect (17) of the present disclosure relates to a display assembly according to aspect (16), wherein the light source comprises a display laminated to the substrate, the display comprising one of a liquid crystal display, an organic light emitting diode display, a μLED display, a quantum dot display, and a laser display.

[0023] An aspect (18) of the present disclosure relates to a display assembly according to any of aspects (16) to (17), wherein the dead-front article exhibits a first maximum ΔE value, calculated using the CIE 76 formula, between two different positions of the dead-front article that is 5.0 or less when the light source emits light at the white point of the light source.

[0024] Aspect (19) of the present disclosure relates to a display assembly according to aspect (18), wherein the first maximum ΔE value is 2.0 or less.

[0025] The embodiment (20) of the present disclosure is a method for detecting a target L * Value, target a * Values, and goals * When emitting light having a value, the dead front article has a target L of 5.0 or less. * , a * , and b * value and the measured L * , a * , and b * The display assembly according to embodiment (16), wherein the second maximum ΔE value calculated using the CIE 76 formula is between 0.01 and 0.1.

[0026] An embodiment (21) of the present disclosure relates to a display assembly according to embodiment (20), wherein the second maximum ΔE value is 2.0 or less.

[0027] An embodiment (22) of the present disclosure relates to a display assembly according to any one of the embodiments (16) to (21), wherein the intermediate layer has a refractive index of 1.8 or more or 1.2 or less.

[0028] Aspect (23) of the present disclosure relates to a display assembly according to any one of aspects (16) to (22), wherein the intermediate layer includes at least one of a clear ink, a white ink, or a gray ink.

[0029] Aspect (24) of the present disclosure relates to a display assembly according to any one of aspects (16) to (22), wherein the intermediate layer comprises a metal layer.

[0030] Aspect (25) of the present disclosure relates to a display assembly according to any of aspects (16) to (22), wherein the intermediate layer includes an air gap between the first ink layer and the second ink layer, and the second ink layer is disposed on a surface of a second substrate held in a fixed relationship relative to the substrate.

[0031] Aspect (26) of the present disclosure relates to a display assembly according to any of aspects (16) to (22), wherein the intermediate layer has a refractive index of 1.8 or greater and includes at least one of Nb2O5, Ta2O5, ZrO2, HfO2, Si3N4, SiON, YO3, TiO2, and a transparent conductive oxide, a first ink layer is disposed adjacent to a first surface of the intermediate layer that is adjacent to the substrate, and a second ink layer is disposed directly on the second surface of the intermediate layer.

[0032] Aspect (27) of the present disclosure relates to a display assembly according to any of aspects (16)-(22), wherein the intermediate layer comprises a multilayer stack comprising alternating layers of one or more high refractive index materials and one or more low refractive index materials, the multilayer stack comprising 2 to 20 alternating layers, wherein the one or more low refractive index materials have a refractive index less than 1.6 at 550 nm and the one or more high refractive index materials have a refractive index greater than 1.6 at 550 nm.

[0033] Aspect (28) of the present disclosure relates to a display assembly according to any of aspects (16) to (22), wherein the intermediate layer includes an electrochromic layer configured to change between a first light transmission state and a second light transmission state, and wherein the average transmittance of the intermediate layer over the wavelength range is lower in the first light transmission state.

[0034] Aspect (29) of the present disclosure relates to a display assembly according to any of aspects (16) to (21), wherein the intermediate layer includes a second substrate and a reflective layer disposed on a surface of the second substrate adjacent to one of the first ink layer and the second ink layer, the first ink layer being disposed on a first surface of the second substrate adjacent to the substrate, and the second ink layer being disposed on a second surface of the second substrate.

[0035] Aspect (30) of the present disclosure relates to a method of manufacturing a display assembly, the method including the steps of: determining a first pattern in a first plurality of regions for a first ink layer; determining a second pattern in a second plurality of regions for a second ink layer, the second plurality of regions being configured to suppress deviation of the appearance of the first plurality of regions from a target appearance in transmission; and disposing the second ink layer and the first ink layer on a substrate such that an intermediate layer is disposed between the first ink layer and the second ink layer, the intermediate layer exhibiting an average reflectance of 1.0% or greater over a wavelength range of 400 nm to 700 nm for light initially incident on a surface of the intermediate layer closest to the substrate.

[0036] Aspect (31) of the present disclosure relates to the method according to aspect (30), in which the step of determining the second pattern includes the steps of: determining XYZ color coordinate values ​​exhibited by each of the first plurality of regions when a light source emits light at the white point of the light source through the first ink layer; and calculating a ratio of a target XYZ color coordinate value to the XYZ color coordinate values ​​to determine XYZ color coordinate values ​​for each of the second plurality of regions, wherein the XYZ color coordinate values ​​are greater than or equal to 0.3 and less than or equal to 0.5.

[0037] Aspect (32) of the present disclosure relates to the method of aspect (30), further comprising attaching the substrate, the first ink layer, the intermediate layer, and the second ink layer to a light source, such that the light source is configured to emit light having an illumination spectrum transmitted through the second ink layer, the intermediate layer, the first ink layer, and the substrate.

[0038] Aspect (33) of the present disclosure relates to the method according to aspect (32), wherein the intermediate layer comprises an ink layer printed directly on the first ink layer, the second ink layer is printed directly on the intermediate layer, and the step of attaching the substrate, the first ink layer, the intermediate layer, and the second ink layer to the light source comprises laminating the light source to the substrate.

[0039] Aspect (34) of the present disclosure relates to the method according to aspect (32), wherein the intermediate layer includes a gap disposed between the first ink layer and the second ink layer, the second ink layer is printed on a second substrate held in a fixed relationship relative to the substrate, and wherein attaching the substrate, first ink layer, intermediate layer, and second ink layer to the light source includes laminating the second substrate to the light source, and attaching the light source and second substrate to the substrate such that the second ink layer is held in a spaced-apart relationship relative to the substrate to form the gap.

[0040] Aspect (35) of the present disclosure relates to the method according to aspect (32), wherein the intermediate layer comprises a second substrate, the second ink layer is disposed on a surface of the second substrate, and attaching the substrate, the first ink layer, the intermediate layer, and the second ink layer to the light source comprises laminating the second substrate to the light source, and laminating the light source to the substrate such that the second substrate is disposed between the substrate and the light source.

[0041] An embodiment (36) of the present disclosure relates to the method according to embodiment (35), wherein the second substrate has a refractive index of 1.8 or more or 1.2 or less, and the first and second ink layers are disposed directly on the surface of the second substrate.

[0042] An embodiment (37) of the present disclosure relates to the method according to embodiment (35), wherein the second substrate has a refractive index greater than 1.2 and less than 1.8, and the intermediate layer further comprises a reflective layer disposed on a surface of the second substrate.

[0043] Aspect (38) of the present disclosure relates to a method according to any of aspects (32) to (37), wherein the step of determining the second pattern includes the steps of: determining a first set of RGB values ​​for a first plurality of regions based on light emitted by a light source; calculating a second set of RGB values ​​for a second plurality of regions based on a target RGB value and the first set of RGB values; and converting the second set of RGB values ​​for each of the second plurality of regions to an ink combination for each of the second plurality of regions using a subtractive color model.

[0044] It is to be understood that both the foregoing general description and the following detailed description are exemplary only and are intended to provide an overview or framework for understanding the nature and character of the claims. The accompanying drawings are included to provide a further understanding, and are incorporated into and constitute a part of this specification. The drawings illustrate one or more embodiment(s), and together with the description, serve to explain the principles and operation of the various embodiments. [Brief explanation of the drawings]

[0045] The accompanying drawings, which are incorporated in and form a part of this specification, illustrate several aspects of the invention and, together with the description, serve to explain the principles of the invention. [Figure 1] 1 is a perspective view of a vehicle cabin with a vehicle cabin system having a display according to one or more embodiments of the present disclosure. [Figure 2] 2 is a diagram of a display of a cabin system taken through line 2-2 shown in FIG. 1, in accordance with one or more embodiments of the present disclosure. [Figure 3A] 3A-3C illustrate a dead-front assembly of the display shown in FIGS. 1-2, in accordance with one or more embodiments of the present disclosure. [Figure 3B] FIG. 3B illustrates a first plurality of regions of the first ink layer of the dead front assembly shown in FIG. 3A in accordance with one or more embodiments of the present disclosure. [Figure 3C] FIG. 3B illustrates a second plurality of regions of the second ink layer of the dead front assembly shown in FIG. 3A in accordance with one or more embodiments of the present disclosure. [Figure 4A] 1. An image of a first ink layer disposed on a transparent film according to one or more embodiments of the present disclosure. [Figure 4B] 4B is a plot of a target optical transmission spectrum of a dead-front article, a first transmission spectrum associated with the first ink layer shown in FIG. 4A, and a second transmission spectrum associated with the second ink layer, according to one or more embodiments of the present disclosure. [Figure 4C] 4B is an image of a second ink layer configured to suppress the appearance of the first ink layer shown in FIG. 4A in transmission, according to one or more embodiments of the present disclosure. [Figure 4D] 4A and 4C disposed on a non-emitting, ambient-reflecting display, according to one or more embodiments of the present disclosure. [Figure 4E] 4D when the display is emitting white light, according to one or more embodiments of the present disclosure. [Figure 4F] 4D when the display is emitting an image transmitted through the prototype, according to one or more embodiments of the present disclosure. [Figure 5] 1 is a plot of predicted reflectance from an interface of a dead-front assembly as a function of refractive index of an intermediate layer between a first ink layer and a second ink layer, according to one or more embodiments of the present disclosure. [Figure 6] 1 is a flow diagram of a method for manufacturing a dead-front article according to one or more embodiments of the present disclosure. [Figure 7] FIG. 1 illustrates a substrate according to one or more embodiments of the present disclosure. DETAILED DESCRIPTION OF THE INVENTION

[0046] Generally, referring to the figures, an article providing dead-front functionality for various applications is described herein. The article includes a substrate and a dead-front assembly disposed on a surface of the substrate. The dead-front assembly includes a first ink layer configured to provide the article with a desired appearance upon reflection of light initially incident on the substrate and reflected off the dead-front assembly. The first ink layer can comprise a printed image of a suitable pattern (e.g., wood grain, woven fabric, or any other suitable pattern) selected to provide the article with a uniform appearance with other objects surrounding the article. Although the printed image provides the desired appearance upon reflection, it may not have the desired appearance (e.g., in terms of one or more of perceived color and transmission spectrum) upon transmission of light initially incident on the dead-front assembly and transmitted through the substrate. Therefore, the dead-front assembly further includes a second ink layer and an intermediate layer disposed between the first and second ink layers. The intermediate layer exhibits an average reflectance of at least 1% (e.g., at least 2%, at least 4%, at least 8%) over the wavelength range of 400 nm to 700 nm to promote visibility of the printed image in reflection. The second ink layer is configured to suppress deviations from the desired appearance of the first ink layer in transmission. In this regard, the overlapping regions of the first and second ink layers are designed so that various portions of the article exhibit targeted light transmission performance attributes. Specific regions of the second ink layer are tailored to the light transmission characteristics of the overlapping regions of the first ink layer to achieve desired optical performance in transmission. In other words, the second ink layer can form an inverse pattern of the pattern formed by the first ink layer, with this inverse calculated based on the desired light transmission performance attributes (e.g., transmission spectrum, phototropic transmission, perceived color in terms of XYZ coordinates) of the specific region of the article. As a result, an image emitted by a light source (e.g., a display panel) can be transmitted through the article with minimal color distortion, even when the first ink layer would tend to cause color distortion of that image when isolated (without the second ink layer).The second ink layer can prevent the first ink layer from changing the perceived color of various portions of the image transmitted through the article, regardless of the colored appearance of the first ink layer in reflection.

[0047] The dead-front articles described herein may find use in any application where it is desirable to provide an article whose appearance deviates from a standard depending on whether the article is viewed in reflection or transmission. A particular application where such different appearances in reflection and transmission are desirable is in automotive interior displays, where it is desirable to provide a display that is hidden or blends in with surrounding objects (e.g., center console, dashboard, seat back) when the display is off, and presents a clear image to the user when the display is on. The first ink layer and intermediate layer described herein help to provide the glass article with a desired appearance in reflection (e.g., from ambient light), while the second ink layer suppresses the appearance of the first ink layer in images transmitted through the article. The perceived color effect of the image provided by the display caused by the first ink layer can be suppressed or even eliminated by incorporating the second ink layer according to the methods described herein. Additionally, the articles described herein can also provide a relatively low overall light transmittance (measured through the combination of the substrate and dead-front assembly) (e.g., average light transmittance from 400 nm to 700 nm of 60% or less, 50% or less, 40% or less, 30% or less, 20% or less, but 5% or more or 10% or more, so as to allow a reasonable portion of the image emitted by the display to pass through) such that the dead-front assembly hides various components of the display (e.g., borders of the display, electrical connections) from view, thereby effectively hiding the display when not in operation.

[0048] As used herein, the terms "light transmittance," "percent transmittance," and "transmittance" are used interchangeably and refer to the percentage of light transmitted through an article over the wavelength range of interest. The "average transmittance" for light in a particular wavelength range is determined by averaging the measured light transmittance at all integer wavelengths within that wavelength range.

[0049] As used herein, the terms "optical reflectance," "percent reflectance," and "reflectance" are used interchangeably and refer to the percentage of light reflected from an article over the wavelength range of interest. When the reflectance of a particular surface is referenced, the referenced value applies only to a single surface of the glass article (e.g., of the surface of a variable transmittance component). The "average optical reflectance" for light in a particular wavelength range is determined by averaging the measured optical reflectance at all integer wavelengths within that wavelength range.

[0050] FIG. 1 illustrates a vehicle cabin 1000 with three different vehicle cabin systems 100, 200, and 300 according to example embodiments. Vehicle cabin system 100 includes a center console base 110 having a curved surface 120 that includes a display 130. Vehicle cabin system 200 includes a dashboard base 210 having a curved surface 220 that includes a display 230. Dashboard base 210 typically includes an instrument panel 215 that may also include a display. Vehicle cabin system 300 includes a dashboard steering wheel base 310 having a curved surface 320 and a display 330. In one or more embodiments, the vehicle cabin system may include a base that is an armrest, pillar, seat back, floorboard, headrest, door panel, or any portion of the vehicle interior that includes a curved surface. In embodiments, displays 130, 230, and 330 are flat and include cover glass with a flat major surface. In embodiments, one or more of the displays 130, 230, 330 are curved, and the curved display may include a curved cover glass that may be hot-formed or cold-formed to have such a curvature. For example, such an embodiment may include a dead-front assembly as described herein disposed on a cold-formed glass substrate (e.g., either before or after the glass is cold-formed).Such cold forming may include any of the techniques described in U.S. Patent Application Publication No. 2019 / 0329531A1, entitled "Laminating thin strengthened glass to curved molded plastic surface for decorative and display cover applications," U.S. Patent Application Publication No. 2019 / 0315648A1, entitled "Cold-formed glass article and assembly process thereof," U.S. Patent Application Publication No. 2019 / 0012033A1, entitled "Vehicle interior systems having a curved cover glass and a display or touch panel and methods for forming the same," and U.S. Patent Application No. 17 / 214124, entitled "Curved glass constructions and methods for forming the same," all of which are incorporated herein by reference.

[0051] Embodiments of the glass articles described herein can be used in any or all of the cabin systems 100, 200, and 300. While FIG. 1 illustrates the interior of an automobile, various embodiments of the cabin system may be incorporated into any type of vehicle, including trains, automobiles (e.g., cars, trucks, buses, etc.), watercraft (boats, ships, submarines, etc.), and aircraft (e.g., drones, planes, jets, helicopters, etc.), including all human-piloted, semi-autonomous, and fully autonomous vehicles. Additionally, while the description herein primarily relates to the use of glass articles in vehicle displays, it should be understood that the various embodiments described herein may be used in any type of display application. The present disclosure is also not limited to display applications and may be used in any dead-front application.

[0052] FIG. 2 schematically illustrates a cross-sectional view of display 230 taken through line 2-2 in FIG. 1 according to an exemplary embodiment in which display 230 is flat. While FIG. 2 illustrates one example of display 230, it should be understood that displays 130, 330 described herein with respect to FIG. 1 may have similar cross-sectional structures and similarly incorporate the dead-front assembly described herein. Display 230 is shown to include a dead-front article 400 having a substrate 450 and a dead-front assembly 460 disposed on substrate 450. While display 230 is flat in the embodiment illustrated in FIG. 2, embodiments are also contemplated in which display 230 is curved and dead-front article 400 includes one or more curved surfaces (e.g., as a result of being cold- or hot-formed to have an appropriate curved shape).

[0053] As shown in FIG. 2 , the dead-front article 400 includes at least a substrate 450, a dead-front assembly 460, and, optionally, an opaque layer 500. The substrate 450 has a first major surface 470 facing the viewer and a second major surface 480 on which the dead-front assembly 460 is disposed. In embodiments, the dead-front assembly 460 can be attached to the second major surface 480 using a suitable optically clear adhesive. In embodiments, at least a portion of the dead-front assembly 460 (e.g., the first ink layer 602 shown in FIG. 3A ) can be disposed directly on the second major surface 480 of the substrate 450 (e.g., using an inkjet printer). As used herein, the term “disposing” includes coating, depositing, and / or forming a material on a surface using any method known in the art. The disposed material may constitute a layer, as defined herein. As used herein, the phrase "disposed on" includes instances where a material is formed on a surface such that the material is in direct contact with the surface, as well as instances where a material is formed on a surface with one or more intervening materials between the disposed material and the surface. The intervening materials may constitute a layer, as described herein. The term "layer" may include a single layer or may include one or more sublayers. Such sublayers may be in direct contact with each other. The sublayers may be formed of the same material or two or more different materials. In one or more alternative embodiments, such sublayers may have an intervening layer of a different material disposed therebetween. In one or more embodiments, a layer may include one or more adjacent continuous layers and / or one or more discontinuous intermittent layers (i.e., layers having different materials formed adjacent to each other). A layer or sublayer may be formed by any method known in the art, including a separate deposition process or a sequential deposition process. In one or more embodiments, a layer may be formed using only a sequential deposition process or only a separate deposition process.

[0054] In embodiments, substrate 450 is a glass substrate, optionally chemically strengthened, having a thickness of 0.05 to 2.0 mm. Details of such glass substrates are described herein with respect to FIG. 7. While embodiments in which substrate 450 is a glass substrate are preferred, alternative embodiments may include substrates made from alternative materials, such as transparent plastics such as PMMA, PMMA / PC, PMMA / PC / PMMA, polycarbonate, etc. As described in more detail below, in embodiments, if included, an opaque layer 500 is printed on the second major surface 480 of substrate 450. In embodiments, opaque layer 500 is printed on the dead-front assembly 460.

[0055] In embodiments, the dead-front article 400 includes a functional surface layer 490. The functional surface layer 490 can be tailored to provide one or more of a variety of functions. For example, the functional surface layer 490 can be an optical coating tailored to provide easy-to-clean performance, anti-glare properties, and / or anti-reflective properties. In the case of an anti-reflective functional surface layer, such a layer can be formed using multiple layers having alternating high and low refractive indices. Non-limiting examples of low refractive index films include SiO2, MgF2, and Al2O3, while non-limiting examples of high refractive index films include Nb2O5, TiO2, ZrO2, HfO2, and YO3. In embodiments, the total thickness of such an optical coating (which may be disposed over an anti-glare surface or a smooth substrate surface) is 5 nm to 750 nm. In addition, in embodiments, the functional surface layer 490 that provides easy-to-clean performance also provides a coating / treatment for enhanced feel and / or fingerprint reduction for touch panels. In some embodiments, the functional surface layer 490 is integral with the first surface of the substrate. For example, such a functional surface layer can include an etched surface on the first surface of the substrate 450 that provides an anti-glare surface (or, for example, a haze of 2% to 10%). In embodiments, both the first major surface 470 and the second major surface 480 of the dead-front article 400 include any of the functional layers described herein.

[0056] In embodiments, the opaque layer 500, if included, is made from a suitable ink (e.g., a heat-curable ink, a light-curable ink) and has a relatively high optical density, e.g., an optical density greater than 3, 4 or greater, or 5 or greater, to block the transmission of light. In embodiments, the opaque layer 500 is used to block light from passing through certain areas of the dead-front article 400. In embodiments, the opaque layer 500 obscures functional or non-decorative elements provided for the operation of the dead-front article 400. In embodiments, the opaque layer 500 is provided to outline backlit icons and / or other graphics (not shown) to increase contrast at the edges of such icons and / or graphics. The opaque layer 500 can be any color; however, in certain embodiments, the opaque layer 500 is black or gray. In embodiments, opaque layer 500 is applied onto dead-front assembly 460 and / or onto second major surface 480 of substrate 450 by inkjet printing, screen printing, coating, or other suitable technique. Generally, opaque layer 500 has a thickness of 25 μm or less (e.g., 1.0 μm to 25.0 μm, 5.0 μm to 25.0 μm, 5.0 μm to 20.0 μm, 5.0 μm to 10.0 μm).

[0057] In embodiments, the opaque layer 500, if included, may be deposited directly onto the second major surface 480 of the substrate 450 or the dead-front assembly 460 using a suitable inkjet process. In embodiments, prior to deposition of the opaque layer 500, the second major surface 480 or the dead-front assembly 460 may be primed using a suitable primer (e.g., an acryloxysilane primer) to enhance adhesion of the opaque layer 500 to the substrate 450 or the dead-front assembly 460. Any suitable treatment may be used on the second major surface 480 to enhance adhesion of the opaque layer 500 to the substrate 450. As described herein, in embodiments, the dead-front article 400 does not include an opaque layer 500.

[0058] In embodiments such as that shown in FIG. 2 , the dead-front article 400 is positioned over or in front of a light source 540. The light source 540 is generally configured to emit light that is transmitted through the substrate 450 for viewing from the first major surface 470. The light emitted by the light source 540 can be monochromatic or span any suitable spectral range to generate a suitable image. The light emitted by the light source 540 can simultaneously exhibit the entire spectral range or use field-sequential color, in which narrower spectral bands are transmitted sequentially in time and combined with a corresponding sequentially displayed image. In one or more embodiments, the light source 540 comprises a display, such as a touch-enabled display including a display and a touch panel. Exemplary displays include LED displays, quantum dot displays, laser-based displays, DLP MEMS chips, LCDs, OLEDs, transmissive displays, etc. In embodiments, the light source 540 comprises another suitable light-emitting element (e.g., a light-emitting diode or light-emitting diode array, a laser, or other light source).

[0059] In embodiments, if included, the high optical density of the opaque layer 500 causes the area of ​​the dead-front article 400 comprising the opaque layer 500 to have a relatively low light transmittance (e.g., an average transmittance of 1.0% or less, 0.5% or less, or 0.1% or less in the visible spectrum). Thus, the boundary of the opaque layer 500 may define, when the dead-front article 400 is viewed from the first major surface 470, an image region 520 in which the dead-front article 400 may exhibit a relatively high light transmittance to facilitate visibility of light produced by the light source 540, and a peripheral region 530 in which the dead-front article 400 generally exhibits a lower light transmittance than in the image region 520 to facilitate concealment of various components (e.g., electrical connections, mechanical housing, etc.).

[0060] In the illustrated embodiment, the image area 520 is peripherally surrounded by the peripheral area 530. For example, in embodiments, the peripheral area 530 forms a boundary for the image area 520 and completely surrounds the image area 520. This boundary may have a uniform width around all of the image area 520. Alternative embodiments in which the peripheral area 530 does not completely surround the image area 520 are contemplated and within the scope of the present disclosure. For example, in embodiments, the peripheral area 530 may be disposed adjacent to the image area 520 and extend along only one side of the image area 520. The present disclosure is not limited to applications in which the image area 520, having a relatively high light transmittance, is centrally located within the dead-front article 400.

[0061] In embodiments, the opaque layer 500 is omitted, and the dead-front article 400 exhibits consistent optical properties (in terms of reflectance and transmittance) across all of its surface area. For example, in embodiments, the dead-front assembly 460 is configured so that the dead-front article 400 exhibits a uniform appearance when viewed from the first major surface 470, with the light source 540 not emitting light. In embodiments, for example, the light transmittance of the dead-front article 400 may be low enough to obscure components of the light source 540 from view. In embodiments, the dead-front article 400 exhibits an average transmittance (when light is normally incident on the substrate 450) over the wavelength range of 400 nm to 700 nm of 60% or less (e.g., 50% or less, 40% or less, 30% or less, 20% or less, but 5% or more, or 10% or more). As a result, the dead-front assembly 460 can hide the light source 540 from the viewer when the light source 540 is not emitting light, thereby giving the dead-front article 400 a pleasing appearance.

[0062] FIG. 3A schematically illustrates a cross-sectional view of the dead front assembly 460 shown in FIG. 2, according to an exemplary embodiment. As can be seen, the dead front assembly 460 includes an intermediate layer 600, a first ink layer 602 disposed on a first surface of the intermediate layer 600, and a second ink layer 604 disposed on a second surface of the intermediate layer 600. The first ink layer 602 is disposed closer to the substrate 450 (see FIG. 2) than the intermediate layer 600 and the second ink layer 604. In an embodiment, the first ink layer 602 is printed directly onto the second major surface 480 of the substrate 450. In an embodiment, the first ink layer 602 is printed onto the intermediate layer 600, which is then laminated onto the second major surface 480 such that a layer of a suitable optically clear adhesive (not shown) is disposed between the substrate 450 and the first ink layer 602.

[0063] The first ink layer 602 is generally configured to provide the dead-front article 400 with a desired appearance from light that initially strikes the substrate 450, transmits through the first ink layer 602, reflects off the intermediate layer 600, and returns through the first ink layer 602 and the substrate 450. The first ink layer 602 can determine the appearance of the dead-front article 400 in reflection from ambient light. In embodiments, the appearance of the dead-front article 400 in reflection is selected so that the dead-front article 400 blends in with other components surrounding the dead-front article 400 (see FIG. 2). For example, referring to FIG. 1, the first ink layer 602 can be selected to form a pattern that matches the pattern of the dashboard base 210 or other components surrounding the display 230 (e.g., interior trim elements). The pattern formed by the first ink layer 602 includes one or more colors when light transmitted therethrough is perceived by a viewer from the first major surface 470. In embodiments, the first ink layer 602 is incorporated into the substrate 450 (e.g., the substrate 450 may comprise a translucent substrate having spatially varying light transmittance to generate a pattern viewable therethrough). In such embodiments, the dead-front assembly 460 may not include the first ink layer 602 shown in FIG. 3A.

[0064] In embodiments, the first ink layer 602 is printed onto the substrate 450 or interlayer 600 using a subtractive color model, such as the CMY or CMYK color model. In such embodiments, the first ink layer 602 generally constitutes a printed image, where a pattern of ink is printed onto the substrate 450 or interlayer 600 using an appropriate printing device (e.g., an inkjet printing device) according to a pixel pattern. Each pixel can be associated with an area of ​​the first ink layer 602, where multiple dots of CMY inks combine to provide the desired color appearance for that area of ​​the first ink layer 602. The inks used to print the first ink layer 602 (and, as described herein, the second ink layer 604) can be heat-curable or UV-curable inks. Specifically, the inks can consist of at least one or more colorants and a vehicle. The colorants can be soluble or insoluble in the vehicle. In embodiments, the colorants are dry colorants in the form of fine powders. In embodiments, such fine powders have particles ranging in size from 10 nm to 500 nm. Using the CMYK color model, the colorants provide cyan, magenta, yellow, and / or base (black) colors. The colorants are dissolved or suspended in a vehicle. The vehicle can function as a binder, adhering the ink to the surface to which it is applied. Additionally, in embodiments, additives are included in the vehicle, particularly for the purpose of improving adhesion to glass / plastic surfaces. Non-limiting examples of vehicles for colorants include propylene glycol monomethyl ether, diethylene glycol diethyl ether, dimethylacetamide, and toluene. Generally, such vehicles solidify at temperatures between 80°C and 200°C. In embodiments, the ink contains 0.5% to 6% by volume of colorant and 94% to 99.5% by volume of vehicle.

[0065] In embodiments, the pattern formed by the first ink layer 602 is selected based on the context in which the dead-front article 400 is being used. For example, in an automotive interior context, the color pattern in the first ink layer 602 can be one of a wood grain design, a leather grain design, a woven fabric design, a brushed metal design, or other suitable designs so that the dead-front article 400 blends in with its surroundings when viewed from the first major surface 470 and the light source 540 is not emitting light. Therefore, the specific combination of inks used at a particular location in the first ink layer 602 may vary depending on the application and context of the dead-front article 400. In embodiments, the first ink layer has a thickness of at least 1 μm and not more than 6 μm to provide sufficient visibility of the color pattern without impeding light transmission to an extent that would prevent a sufficient amount of light from the light source 540 from penetrating the dead-front article. In embodiments, the optical density of the first ink layer is 0.1 to 0.7 (e.g., 0.1 to 0.5, 0.3 to 0.5) to provide sufficient color visibility in reflection without excessively obscuring the light source 540 so as to degrade display performance. The refractive index (at 550 nm) of the ink used to form the first ink layer 602 may be between 1.30 and 1.60 (e.g., 1.45 or more and 1.55 or less).

[0066] It is believed that most of the perceived color imparted by the first ink layer 602 does not result from light scattering within the ink itself. The ink used to form the first ink layer 602 is highly absorbent at certain wavelengths. Therefore, the perceived color of the first ink layer 602 results from light passing through the first ink layer 602, being reflected, and passing through the first ink layer 602 again. The intermediate layer 600 is configured so that when ambient light is incident on the first major surface 470, the light passes through the first ink layer 602 to provide reflected light that makes the pattern in the first ink layer 602 visible. The intermediate layer 600 exhibits an average reflectance of 1.0% or greater (preferably 2.0% or greater, more preferably 3.0% or greater, and even more preferably 4.0% or greater) over the wavelength range of 400 nm to 700 nm for light initially incident on the surface of the intermediate layer 602 closest to the substrate (normal incidence). In embodiments, the average reflectance of the intermediate layer 600 is 10.0% or less (e.g., 9.0% or less, 8.0% or less, 7.0% or less). Such a reflectance has been found to allow the pattern in the first ink layer 602 to be visible in appropriate light without excessively obscuring the light source 540.

[0067] Various configurations of the interlayer 600 are contemplated and are within the scope of the present disclosure. In embodiments, the interlayer 600 comprises a single layer of material that provides reflectivity at the interface with its adjacent layers (e.g., first and second ink layers 602 and 604, optically clear adhesive). In embodiments, the first and second ink layers 602 and 604 are formed from inks having a refractive index (at 550 nm) of 1.45 or greater and 1.55 or less. Based on the modeling described herein, applicants have determined that providing the interlayer 600 with a material having a refractive index (at 550 nm) of 1.7 or greater or 1.3 or less (preferably 1.8 or greater or 1.2 or less) provides a sufficient refractive index difference to provide suitable reflectivity. Materials with a refractive index of 1.7 or greater include high refractive index glasses and metals or metal oxides, either as thin films or as nanocomposite dispersions in low refractive index resins. Suitable materials for such high refractive index embodiments include, but are not limited to, Nb2O5, Ta2O5, ZrO2, HfO2, Si3N4, SiON, YO3, TiO2, and transparent conductive oxides (such as indium tin oxide). Materials with a refractive index less than 1.2 include MgF or other suitable materials (e.g., material composites, metamaterials, porous materials such as the silica-based porous materials disclosed in Paolo Falcaro et al., "Hierarchical Porous Silica Films with Ultralow Refractive Index," Chemistry of Materials, 2009, Vol. 21, No. 10, pp. 2055-2061, which is incorporated herein by reference in its entirety).

[0068] When such a material (having a refractive index of 1.7 or greater or 1.3 or less) is used for the intermediate layer 600, the thickness of the intermediate layer 600 should be greater than 1 μm, which is greater than the coherence length of light from the external environment (e.g., sunlight) that may be incident on the intermediate layer 600. Layers thinner than 1 μm may introduce angle and wavelength dependence in the reflective performance and exhibit interference effects that degrade the appearance. Such effects can be completely avoided if the intermediate layer 600 is 5 μm or greater in thickness. In such embodiments, the intermediate layer 600 has a thickness of 5 μm or greater and 5 mm or less (e.g., 5 μm or greater and 1.0 mm or less, 5 μm or greater and 500 μm or less, 5 μm or greater and 100 μm or less, 5 μm or greater and 50 μm or less, or 20 μm or greater and 50 μm or less).

[0069] A suitable layer providing a refractive index (at 550 nm) of less than 1.2 is an air gap. That is, in an embodiment, the intermediate layer 600 includes an air gap disposed between the first ink layer 602 and the second ink layer 604. In an embodiment, the air gap has a thickness within the range described in the preceding paragraph to avoid interference effects. In such an embodiment in which the intermediate layer 600 includes an air gap, the dead front assembly 460 can include a support structure 605 configured to hold the first and second ink layers 602 and 604 in a fixed relationship relative to each other (e.g., so that the space between the first and second ink layers 602 and 604 is constant to help reduce wavefront tilt in reflected light caused by the air gap). In an embodiment, the support structure 605 is a frame attached to the substrate 450 (see FIG. 2). For example, the first ink layer 602 may be printed directly on the second major surface 480 (see FIG. 2 ), and the second ink layer 604 may be printed on a second substrate 607 inserted into a support structure 605. The support structure 605 may include one or more structural features (e.g., ledges, grooves) that help position the second substrate 607 having the second ink layer 604 printed thereon in a desired orientation relative to the first ink layer 602, such that an air gap is positioned between the first ink layer 602 and the second ink layer 604. The second substrate 607 may be a suitable transparent material (e.g., having an average transmittance of 80% or greater or 90% or greater), such as glass (e.g., soda lime, aluminosilicate, boroaluminosilicate) or a polymeric material. Such second substrate 607 may have a refractive index (at 550 nm) of 1.45 or greater and 1.65 or less, and a thickness of 10 μm or greater and 100 μm or less (e.g., 10 μm or greater and 75 μm or less, 10 μm or greater and 50 μm or less, 20 μm or greater and 40 μm or less). Second substrate 607 may be included in embodiments in which intermediate layer 600 does not contain voids (e.g., at least one of first and second ink layers 602 and 604 may be disposed on second substrate 607 and then subsequently attached to substrate 450).The second substrate 607 may also be omitted if the intermediate layer 600 is formed from a single layer having a sufficient refractive index to eliminate the need for an additional reflective layer (in such an embodiment, the second ink layer 604 may be disposed directly on this single layer).

[0070] In embodiments, the interlayer 600 includes an additional ink layer. The additional ink layer can comprise a diffusely reflective surface, such as a white ink or a gray ink. If a white ink is used, various suitable pigment colorants, such as TiO2, Sb2O3, BaSO4, BaSO4:ZnS, ZnO, and (PbCO3)2:Pb(OH)2, in a suitable vehicle, can be used. Such a white ink layer can have a whiteness of 10W or more and 60W or less, as measured according to ISO 11475:2004. Such a white ink layer can have a thickness of 1 μm or more and 6.0 μm or less and an optical density of 0.9 to 2.0. If a gray ink is used, the interlayer can be formed from ink using a subtractive color model (e.g., CMY or CMYK). Such a diffuse ink may be less advantageous than other alternatives described herein in that it can blur the image emitted by the light source 540 and produce more sparkle. In embodiments, the additional ink layer can be a reflective (e.g., metallic) ink (e.g., including a high refractive index colorant or an additive of any of the high refractive index materials described herein). In embodiments in which an additional ink layer is used in the intermediate layer 600, the first ink layer 602, the second ink layer 604, and the intermediate layer 600 can each be printed sequentially on the second major surface 480. Alternatively, one or more of the first ink layer 602, the intermediate layer 600, and the second ink layer 604 can be disposed on a second substrate 607, which is then attached to the substrate 450.

[0071] In embodiments, the intermediate layer 600 includes an electrically responsive material configured to change between optically transmissive states in response to an electrical signal provided thereto by a controller (not shown). For example, the intermediate layer 600 can be switched between a first transmissive state with high transmissivity when the light source 540 is emitting light and a second transmissive state with low transmissivity when the light source 540 is not emitting light. In such embodiments, the electrically responsive material can constitute an electrochromic layer, and the intermediate layer 600 can include electrodes, an electrolyte, and an ion reservoir. The electrochromic layer can be made of a suitable inorganic or organic (e.g., electrochromic polymer) material. In embodiments, the electrochromic layer can be made of a suitable oxide (e.g., WO3, NiO, WMoO3). The electrolyte can be made of a suitable material configured to transport protons provided by the ion reservoir. Any suitable existing electrochromic cell structure can be used. Any of the electrically responsive materials described in U.S. Provisional Patent Application No. 63 / 406,335, filed September 14, 2022, which is incorporated herein by reference in its entirety, may be used.

[0072] In embodiments, the intermediate layer 600 comprises a multi-layer structure. In embodiments, the intermediate layer 600 includes a layer of transparent material (e.g., a second substrate 607 formed from a suitable glass or polymeric material). Such transparent materials may not have a sufficient refractive index difference with adjacent layers to provide suitable reflectivity in isolation. Therefore, the intermediate layer 600 may further include a reflective layer 609 disposed on the second substrate 607. The reflective layer 609 is configured to reflect light in the wavelength range of 400 nm to 700 nm, within any of the suitable ranges described herein. The reflective layer 609 may be disposed adjacent to the first ink layer 602 or the second ink layer 604, or may be disposed on the second substrate 607 (in embodiments, the intermediate layer 600 consists of the second substrate 607 with the reflective layer 609 disposed thereon). In such an embodiment, one of the first and second ink layers 602 and 604 can be disposed on the reflective layer 609, and the other of the first and second ink layers 602 and 604 can be disposed directly on the second substrate 607. Alternatively, the first ink layer 602 can be disposed on the second major surface 480 (see FIG. 2), the reflective layer 609 can be positioned adjacent to the first ink layer 602 (or with a layer of optically clear adhesive disposed therebetween), and the second ink layer 604 can be disposed on the second substrate 607. The reflective layer 609 can be made from a suitable layer of metallic material. In an embodiment, the reflective layer 609 is at least 10 mm thick to avoid the reflective layer 609 interfering with touch panel function. 5 The reflective layer 609 can be fabricated to exhibit a sheet resistance of Ω / □. Suitable materials for the reflective material may include Ni, Cr, Ni-containing alloys, and Cr-containing alloys. Such a reflective layer may have a thickness of less than 2 nm to provide adequate sheet resistance and avoid interfering with touch panel function. In an embodiment, the reflective layer 609 is fabricated from a multi-layer stack of alternating high and low refractive index materials.

[0073] In embodiments, the intermediate layer 600 is not a monolithic layer of a single material (or a monolithic layer with the reflective layer 609 disposed thereon), but rather comprises a multi-layer stack. The multi-layer stack can include one or more layers of a high refractive index material 603a and one or more layers of a low refractive index material 603b. In embodiments, the stack can include 2 to 20 alternating layers of one or more high refractive index materials 603a and one or more low refractive index materials 603b. The one or more layers of the low refractive index material 603b can have a refractive index of less than 1.6 at 550 nm. Examples of materials suitable for use as the one or more low refractive index materials 603b include glass, polymeric materials, SiO2, Al2O3, GeO2, SiO, AlO x N y , SiO x N y , Si u Al v O x N y , MgO, MgAl2O4, MgF2, BaF2, CaF2, DyF3, YbF3, YF3, CeF3, or Ni, Cr, NiCr, or Ti doped nanocomposites. One or more layers of high refractive index material 603a can have a refractive index greater than 1.6 at 550 nm. Suitable materials for use as one or more high refractive index materials 603a include Ta2O5, Nb2O5, AlN, Si3N4, AlO x N y , SiO x N yExamples of suitable materials include HfO2, TiO2, ZrO2, Y2O3, Al2O3, MoO3, indium tin oxide, and diamond-like carbon. Such alternating stacks can help provide a relatively flat reflection band across the wavelength range of 400 nm to 750 nm, thus minimizing the effect on the perceived color of light transmitted through the dead-front article 400. Selecting such materials also avoids altering touch panel function behind the dead-front. Some embodiments include such alternating stacks in addition to the reflective layer 609 to fine-tune the reflection spectrum and protect the reflective layer 609 from oxidation when the first and second ink layers 602 and 604 are fired at high processing temperatures (e.g., 50°C to 200°C). Such alternating layers may be deposited using any suitable discrete or sequential deposition process (e.g., physical vapor deposition). The inclusion of such a stack would be disadvantageous in that incorporating multiple layers may make the fabrication more expensive than embodiments including less expensive materials (e.g., an air gap and second substrate 607, a monolithic layer of high refractive index material).

[0074] Still referring to FIG. 3A , regardless of the specific structure used for the intermediate layer 600, the pattern in the first ink layer 602 generally provides a desired appearance in reflection by varying the light transmission properties of the substrate 450. Light reflected from the intermediate layer 600 is transmitted through the first ink layer 602 to provide a desired appearance in reflection. More specifically, the specific spectrum of light transmitted through the first ink layer 602 can be varied as a function of position to achieve a particular appearance in reflection. Such transmission variations can alter the appearance of the image rendered by the light source 540 when viewed in transmission through the dead-front article 400 by introducing color distortions into the image. For example, if the first ink layer 602 forms a pattern of two or more colors, different regions of the first ink layer 602 associated with different colors will have different transmission spectra. Such different transmission spectra can alter the perceived color of the light emitted by the light source 540 in a different manner, such that the pattern formed in the first ink layer 602 appears in the image rendered by the light source 540. To illustrate, in an example where the first ink layer 602 forms a wood grain pattern, the wood grain pattern may be visible when the image produced by the light source 540 is transmitted through the dead-front article 400, which may be distracting to the viewer and degrade image quality. In other words, while it is desirable for the pattern formed by the first ink layer 602 to appear in reflection of ambient light when the light source 540 is off, it is generally undesirable for such pattern to appear in light transmitted through the dead-front article 400. The change in the light transmission performance of the substrate 450 caused by the incorporation of the first ink layer 602 causes at least a portion of the substrate 450 (where the first ink layer 602 is disposed) to deviate from the desired appearance in transmission.

[0075] In view of the foregoing, the dead front assembly 460 includes a second ink layer 604 to counter deviations from the desired appearance of transmission associated with the first ink layer 602. The structure of the second ink layer 604 will be further understood in view of FIGS. 3B and 3C. FIG. 3B schematically illustrates a portion of an image 606 imparted by the first ink layer 602. As can be seen, the first ink layer 602 includes a first plurality of regions 608. Each of the first plurality of regions 608 can be a portion of the image 606 configured to exhibit a consistent color from reflected light. In an embodiment, for example, each of the first plurality of regions 608 corresponds to a pixel of an image input to a printing device (e.g., an inkjet printing device). The size of each of the first plurality of regions 608 will depend on the manner in which the first ink layer 602 is printed (e.g., droplet size, printing resolution, etc.). Although the first plurality of regions 608 are shown to be the same size and shape, it should be understood that the first plurality of regions 608 may deviate in size and shape from one another due to the inherent nature of the printing process.

[0076] In embodiments, at least some of the first plurality of regions 608 may deviate from one another in terms of color. For example, region 608a may exhibit a first color (or first transmission spectrum) when light from light source 540 is transmitted through it, while region 608b may exhibit a second color (or second transmission spectrum) when light from light source 540 is transmitted through it. Even when the same light from light source 540 is transmitted through both regions 608a and 608b, portions of an image overlying regions 608a and 608b may appear different in color from one another. This example demonstrates how different absorption spectra associated with inks used to form various regions of first ink layer 602 can introduce undesirable color variations in an image conveyed by light source 540 through dead-front article 400.

[0077] FIG. 4A shows an exemplary first ink layer 630 printed on a transparent film according to examples described herein. The first ink layer 630 is printed to exhibit a wood grain pattern, with different regions of the first ink layer 630 having different transmission spectra such that the wood grain pattern is visible through the first ink layer 630 when the first ink layer 630 is illuminated by ambient light. FIG. 4B shows a plot 634 of a transmission spectrum 636 of a region of the first ink layer 630 within a portion 632 configured to exhibit a brown color. As can be seen, the transmission spectrum of the first ink layer 630 is non-uniform across the wavelength range of 400 nm to 700 nm due to the absorption spectrum of the ink used to form the first ink layer 630 within the depicted region. As a result, any light having a spectrum different from transmission spectrum 636 will be altered by transmission through first ink layer 630, which tends to absorb more light at wavelengths below 550 nm than at wavelengths above 550 nm. Such an effect will alter the color appearance of pixels of an image transmitted through first ink layer 630 and presented by a display.

[0078] Transmission spectrum 636 is a modeled example of an ink layer designed to exhibit a brown color based on the CMY color model placed on a transparent substrate. A spectrally flat 3% Fresnel reflection was assumed on both sides of the substrate. In general, the transmittance is

[0079]

number

[0080] Approximated by removing the low amplitude terms, the transmittance of the substrate with the first ink layer 630 can be calculated as:

[0081]

number

[0082] Assuming the presence of a second ink layer disposed on a second transparent substrate (such as the second ink layer 604 and second substrate 607 shown in FIG. 3A), the transmission spectrum of the second substrate can be approximated as:

[0083]

number

[0084] Using the above approximation, it can be calculated as: If the first and second substrates in this example are placed optically in series, the combined transmission through the two substrates with an air gap between them is approximately equal to the product of T1(λ) and T2(λ).

[0085] Still referring to this example of a first and second ink layer disposed on two transparent substrates, the total reflectance from the composite laminate is

[0086]

number

[0087] is given by

[0088] Assuming a small Fresnel coefficient (e.g., assuming the first and second substrates have refractive indices comparable to the first and second ink layers), and simplifying Equation 4 with a series of approximations (neglecting the back surface contribution of the second substrate), the total reflectance is

[0089]

number

[0090] This indicates that the reflected color will primarily come from the square of the transmission spectrum of the front ink. The eliminated terms in Equations 4 and 5 will affect the contrast of the reflected image, but Applicant believes that these terms are generally spectrally flat by design. Such terms do not affect the perceived color, only the contrast of the image.

[0091] The previous analysis of Equations 1-5 clearly demonstrates that the overall appearance of the laminate in transmission depends on the transmission spectra of both the first and second ink layers, while the appearance in reflection depends primarily on the first ink layer. This indicates that the second ink layer can be used to affect the appearance of the article in transmission, while having relatively little effect on the appearance of the article in reflection. With this in mind, a target transmission spectrum T target (λ) can be provided. Furthermore, the known transmission spectrum T ink1 Considering the transmission spectrum 636 shown in FIG. 4B, the product of T1(λ) and T2(λ) calculated by Equations 2 and 3 is T target (λ) so that the transmission spectrum T of the second ink layer is equal to ink2 (λ) (shown as transmission spectrum 638 in FIG. 4B). A further approximation of the product of T1(λ) and T2(λ) calculated by Equations 2-3 by removing small amplitude terms is T ink2 (λ) is

[0092]

number

[0093] can be approximately calculated as

[0094] T target(λ) is generally selected so that light transmitted through the article has a desired appearance. In the example shown in FIG. 4B, the target transmission spectrum 639 is a neutral gray with a constant transmittance of approximately 40% throughout the wavelength range from 400 nm to 700 nm. A constant value greater than or equal to 20% and less than or equal to 60% is considered suitable to give the article a generally indeterminate appearance in transmission while blocking enough light to promote an effective dead-front effect. Utilizing a constant as the target transmission spectrum 639 beneficially ensures that the combination of the first and second ink layers does not change the perceived color of any light transmitted through the composite laminate. Various target transmission spectra are contemplated and within the scope of the present disclosure. For example, a graded target transmission spectrum (e.g., transmittance increases and decreases with increasing wavelength), a stepped target transmission spectrum, or other suitable targets can be used depending on any visual effect desired to be achieved by the dead-front article.

[0095] Inputting the target transmission spectrum 639 and the transmission spectrum 636 into Equation 6 yields a transmission spectrum 638 for a region of the second ink layer 604. For example, returning to the example shown in FIGS. 3A-3C, FIG. 3C schematically illustrates a portion of an image 610 provided by the second ink layer 604 according to this example. As can be seen, the second ink layer 604 includes a second plurality of regions 612. Each of the second plurality of regions 612 can be part of the image 610 configured to exhibit a consistent color. The second plurality of regions 612 generally overlap with the first plurality of regions 608 of the first ink layer 602 along an alignment axis 620 (see FIG. 3A). In an embodiment, the alignment axis 620 extends in a direction perpendicular to the first and second major surfaces 470 and 480 of the substrate 450. As can be seen, the second ink layer 604 includes a region 612a that overlaps with a region 608a of the first ink layer 602. In one example, the ink used to form the region 612a is selected to provide a transmission spectrum (or a metameric equivalent) calculated using Equation 6 based on the transmission spectrum of the region 608a. Repeating such a process for each region of the image 606 of the first ink layer 602 provides a pattern for the second ink layer 604 such that the second ink layer 604 is selected to provide a desired appearance in transmission without significantly changing the appearance of the dead-front article 400 when viewed in reflected ambient light.

[0096] Such an approach to calculating the inverse color of each of the second plurality of regions 612 of the second ink layer 604 based on the colors of the overlapping regions of the first plurality of regions 608 of the first ink layer 602 is computationally complex. This approach to calculating the inverse color can be approximated by converting the image of the first ink layer 602 to RGB color space and using that RGB color space to calculate the color value of the second ink layer 604. The visible spectrum (400 nm to 700 nm) of each of the first plurality of regions 608 can be converted to tristimulus X, Y, and Z coordinates according to the CIE 1931 color space. The X, Y, and Z values ​​can then be converted to appropriate RGB values ​​based on the illuminant 540 being used, which can be used to calculate the inverse of the first ink layer 602 based on the target color value for each region of the dead-front article 400 (or the overlapping of the first plurality of regions 608 and the second plurality of regions 612).

[0097] In an illustrative example, the X, Y, and Z coordinates of the transmission spectra 636, 638, and 639 shown in FIG. 4B were calculated based on the D65 illuminant using the CIE 1931 2° standard observer found in ISO / CIE 11664-2:2019, "Colorimetry - Part 1: CIE standard colorimetric observers," which is incorporated herein by reference in its entirety. The X, Y, and Z values ​​(integrals evaluated from 380 nm to 780 nm) were then converted to sRGB values ​​according to the IEC 61966-2-1:1999 standard. The results are provided in Table 1 below.

[0098] [Table 1]

[0099] R totalThe values ​​are based on the reflectance spectrum calculated using Equation 4. The values ​​in Table 1 were obtained without gamma scaling of the RGB values. When the XYZ values ​​were normalized to values ​​relative to the CIE 1931 D65 white point value and the sRGB values ​​were scaled from 0 to 255, the results are given in Table 2 below.

[0100] [Table 2]

[0101] As shown in Tables 1 and 2, Applicant has determined that the XYZ values ​​calculated based on the target transmission spectrum 639 and transmission spectra 636 and 638 shown in FIG. 4B have the following approximate relationships:

[0102]

number

[0103]

number

[0104]

number

[0105] We unexpectedly found that the sRGB values ​​(unscaled) also satisfy the following approximate relationship:

[0106]

number

[0107]

number

[0108]

number

[0109] While not intending to be bound by theory, the ratios of Equations 7-12 are believed to be fairly accurate approximations (within 10% of the values ​​actually calculated in Tables 1 and 2) due to the flat regions in the limited spectral ranges of the transmission spectra and CIE color matching spectra of the various CMYK inks. Nevertheless, Applicant believes that the ratios of Equations 7-12 serve as an efficient way to calculate the inverse image of the first ink layer 602 to determine the pattern of the second ink layer 604. The RGB values ​​of the various pixels in the image formed by the first ink layer 602 can be inverted and multiplied by the target values ​​of the dead-front article 400 to determine the RGB values ​​of each pixel of the second ink layer 604. The target RGB values ​​(without gamma correction and scaling) can be greater than or equal to 90 and less than or equal to 110 (e.g., each of the RGB values ​​can be the same so that the dead-front article 400 is configured to exhibit a uniform gray appearance when illuminated with a white light source). Such RGB values ​​can be input into an ICC file associated with the printing device, which will convert them to CMYK values ​​for printing each pixel of the image formed by the second ink layer 604. Target XYZ values ​​for each of the pixels may also be used. In an embodiment, such target XYZ values ​​are greater than or equal to 0.30 and less than or equal to 0.50 (if not normalized to the D65 white point value).

[0110] FIG. 4C shows an example second ink layer 640 calculated and printed using such an approach (e.g., this pattern was calculated using the target RGB values ​​in Table 1 and the RGB values ​​associated with the regions of the first ink layer 630 shown in FIG. 4A , and then the calculated pattern was printed onto a transparency film). As can be seen, the second ink layer 640 is the inverse image of the first ink layer 630 shown in FIG. 4A , with regions of the first ink layer 630 having relatively high light transmittance overlapping regions of the second ink layer 640 having relatively low light transmittance, and vice versa. When the first and second ink layers 630 and 640 shown in FIGS. 4A and 4C are aligned, the transparent first ink layer 630 pattern is largely eliminated, demonstrating the effectiveness of the approach described herein.

[0111] Referring to Figures 4D-4F, a prototype was constructed using the calculations described for the first and second ink layers 630 and 640 shown in Figures 4A and 4C (although using different images of the wood grain pattern). Specifically, to construct the prototype, the first and second ink layers 602 and 604 were aligned with each other and placed on the display with a gap (as intermediate layer 600) between them. The ink layers were printed using a LaserJet® printer. Figure 4D is an image 644 of the prototype on a black display. As can be seen, the wood grain pattern formed by the first ink layer 630 is clearly visible in the reflection from the ambient light. Figure 4E is an image 646 of the prototype with the display emitting ambient light. As can be seen, the wood grain pattern is no longer visible because the light from the display has washed out the reflected light. Figure 4F is an image 648 of the prototype with the display emitting an image. The grain pattern is virtually invisible, and the image appears clear with little color distortion (the combination of the ink layers only slightly reduces the brightness of the image). These results demonstrate the effectiveness of the techniques described herein in providing a dead-front article that exhibits a desired appearance in reflection from ambient light, while also facilitating the transmission of the image therethrough with improved color distortion performance compared to certain existing dead-front techniques. In the construction example, best results were achieved when no gamma correction was performed while calculating the RGB values ​​of the image formed in the first ink layer 602. However, in such a case, the minimum R, G, or B value across all pixels was 255. * T target It was beneficial to use the light-toned image I1, which is limited to T target = 0.4, the smallest value for any of the colors in the image of the first ink layer 602 is greater than 102. If the first ink layer 602 has a pixel with a smaller RGB value, the corresponding color of that pixel in the inverse image will need to be greater than 255. For color technologies with more than 8-bit color, e.g., n-bit color, this threshold is T target * (2 n-1).

[0112] In the previous examples and Tables 1 and 2, we assumed that a D65 illuminant was used for both reflection and transmission. The D65 illuminant is suitable for simulating outdoor ambient light (and would also be suitable for measuring the perceived color of the dead-front article 400 in reflection). However, in determining the appropriate RGB values ​​in transmission, it may be useful to consider the particular illuminant 540 being used. For example, the spectral power distribution (I(λ)) associated with the particular illuminant 540 being used is input into the CIE 1931 color space XYZ equations (e.g., the illumination spectrum may be associated with an illuminant 540 that emits a white image). However, the ratios in Equations 7 through 12 are still believed to provide relatively accurate results for most commercially available display panels.

[0113] 2, the effect of the second ink layer 604 described herein is that the color appearance of light emitted by the light source 540 is not perceptibly altered (at least not significantly) by passing through the dead-front assembly 460. The overlapping regions of the first and second pluralities of regions 608 and 612 (see FIGS. 3B-3C) are specially constructed to avoid the perceived color of the light emitted by the light source 540 being altered by transmission through the dead-front article 400. In an embodiment, the light emitted by a portion of the light source 540 (e.g., a particular pixel or sub-array of pixels of a display) is chromatic aberration-free, i.e., a target CIE L * a * b * The area of ​​the first and second ink layers 602 and 604 that overlaps with that portion of the light source 540 can have a particular color defined by an L value (measured when light is emitted by the light source 540 and not transmitted through the dead-front article 400). The area of ​​the first and second ink layers 602 and 604 that overlap with that portion of the light source 540 can have a particular color defined by an L value (measured when light is emitted by the light source 540 and not transmitted through the dead-front article 400) that is equal to or less than 5.0 (e.g., 4.5 or less, 4.0 or less, 3.5 or less, 3.0 or less, 2.5 or less, 2.0 or less, 1.5 or less, or even 1.0 or less) of the light source 540 as a reference value. * a * b *The value can be configured to indicate a ΔE value, calculated according to the CIE 1976 formula. In other words, the light emitted by the light source 540 (e.g., from each pixel or sub-array of pixels) is divided into a series of L * a * b * The first and second ink layers 602 and 604 can exhibit a ΔE value and pass through overlapping pairs of regions of the first and second ink layers 602 and 604. The first and second ink layers 602 and 604 can be configured such that the maximum ΔE value across all of the dead-front article 400 (measured between light transmitted through the dead-front article 400 and a value associated with the isolated light source 540) is 5.0 or less (e.g., 4.5 or less, 4.0 or less, 3.5 or less, 3.0 or less, 2.5 or less, 2.0 or less, 1.5 or less, or even 1.0 or less). In this manner, color distortion between the emitted image and the transmitted image can be minimized even when the first ink layer 602 is specifically manufactured to have a color that deviates from the image imparted by the light source 540 (e.g., at least some of the first plurality of regions 608 have a magnitude greater than 5.0, greater than 10.0, greater than 20.0, greater than 30.0, or even greater than 50.0 when illuminated with a D65 light source). * and b * (can be configured to show a value).

[0114] As used herein, L * value, a * value, and b * The value is the following formula:

[0115]

number

[0116]

number

[0117]

number

[0118] can be calculated from the tristimulus XYZ coordinates in the 1931 CIE color coordinate space (measured with a 2° standard observer) using the formula: W , Y W , and Z W Here are the criteria:

[0119]

number

[0120]

number

[0121]

number

[0122] where: TIFF2025534591000022.tif6114

[0123] are the CIE color matching functions. Unless otherwise specified, the illuminant is a D65 illuminant, but in some cases the illuminant can be illuminant 540 acting as its white point. In equations 13-15, for δ=6 / 29, the function f(t) is

[0124]

number

[0125] is given by

[0126] When the light source 540 is set to a white point (to emit a perfect white image through the dead-front article 400), the light transmitted through the dead-front article 400 from the light source 540 has an L of 50 or greater and 80 or less (e.g., 55 or greater and 75 or less, 60 or greater and 70 or less). *a value of -5.0 or greater and 5.0 or less (e.g., -4.5 or greater and 4.5 or less, -4.0 or greater and 4.0 or less, -3.5 or greater and 3.5 or less, -3.0 or greater and 3.0 or less, -2.5 or greater and 2.5 or less, -1.0 or greater and 1.0 or less) * values, and b values ​​between -5.0 and 5.0 (e.g., between -4.5 and 4.5, between -4.0 and 4.0, between -3.5 and 3.5, between -3.0 and 3.0, between -2.5 and 2.5, between -1.0 and 1.0). * values, such that white light emitted by light source 540 is still perceived as white after being transmitted through dead-front article 400. Furthermore, when light source 540 is set to a white point (e.g., associated with a particular display panel), the light transmitted through dead-front article 400 can also exhibit a ΔE value that is within the ranges described herein.

[0127] While the RGB values ​​(or XYZ values) for the regions of the first and second ink layers 602 and 604 can be calculated based on a particular light source and target values, it is believed that white light from other light sources (e.g., other than light source 540) transmitted through the dead-front article 400 will also exhibit a similar appearance. For example, in an embodiment, when light from a D65 light source is transmitted through the dead-front article 400 (first incident on the second ink layer 604 and then normally incident on the substrate 450), the light exhibits an L of 50 or greater and 80 or less (e.g., 55 or greater and 75 or less, 60 or greater and 70 or less). * a value of -5.0 or greater and 5.0 or less (e.g., -4.5 or greater and 4.5 or less, -4.0 or greater and 4.0 or less, -3.5 or greater and 3.5 or less, -3.0 or greater and 3.0 or less, -2.5 or greater and 2.5 or less, -1.0 or greater and 1.0 or less) * values, and b values ​​between -5.0 and 5.0 (e.g., between -4.5 and 4.5, between -4.0 and 4.0, between -3.5 and 3.5, between -3.0 and 3.0, between -2.5 and 2.5, between -1.0 and 1.0). * Indicates the value.

[0128] FIG. 5 is a plot 700 of modeled Fresnel reflections (assuming normal incidence) from two interfaces between the intermediate layer 600 and the first and second ink layers 602 and 604 shown in FIG. 3A (assuming the intermediate layer 600 is monolithic). The first and second ink layers 602 and 604 were assumed to have a refractive index (at 550 nm) of 1.48 in this example. As can be seen, if the refractive index of the intermediate layer 600 is less than 1.3 or greater than 1.7, the total reflectance of the dead front assembly 460 is predicted to be greater than 1.0%, which is believed to be sufficient for certain patterns. If the refractive index of the intermediate layer 600 is greater than or equal to 1.8 or less than or equal to 1.2, the total reflectance of the dead front assembly 460 is predicted to be greater than 2.0%, which helps ensure that patterns formed in the first ink layer 602 are visible in reflection. If the refractive index of the intermediate layer 600 is greater than or equal to 2.0 or less than or equal to 1.1, the total reflectance of the dead front assembly 460 is predicted to be greater than 4.0%. Such greater reflectance values ​​can increase the contrast of the image of the first ink layer 602 when viewed in reflection under ambient light. This analysis indicates a suitable refractive index for the intermediate layer 600 when the reflective layer 609 is not used in the dead front assembly 460.

[0129] FIG. 6 is a flow diagram of a method 800 for manufacturing a dead-front article, according to an example embodiment. The method 800 can be used to manufacture the dead-front article 400 described herein with respect to FIGS. 2-3B and attach a light source 540 thereto. Accordingly, references to the various components shown in FIGS. 2-3B will be helpful in describing the method 800. In block 802, a pattern for the first ink layer 602 is determined. As described herein, the pattern for the first ink layer 602 can be determined based on the context of the dead-front article 400. Depending on the implementation, any suitable pattern (e.g., wood grain, brushed metal, carbon fiber, woven fabric) can be used. The pattern can be determined based on an image of another structural element (e.g., a dashboard, seat, or trim element component) to be used with the dead-front article 400. For example, an image of a wood grain trim element can be taken and used as the target pattern for the first ink layer 602 so that the dead-front article 400 blends in with its surrounding components. The pattern may include a matrix of RGB values ​​to be input to a printing device for conversion to CMYK values ​​via an ICC file to facilitate the deposition of ink in the pattern using a subtractive color model.

[0130] In block 804, a pattern of the second ink layer 604 is determined such that the second ink layer 604 is designed to counteract any deviations of the first ink layer from the desired light transmission characteristics. In an embodiment, the desired light transmission characteristics are target color coordinates (e.g., XYZ or RGB values) measured from light transmitted through the dead front assembly 460 and the substrate 450. The light may have an illumination spectrum associated with the light source 540. At least some of the first plurality of regions 608 of the pattern of the first ink layer 602 may exhibit color coordinates that deviate from the desired values ​​when illuminated with light from the light source 540 (having a particular illumination spectrum). The pattern of the second ink layer 604 may be determined by calculating inverse colors for regions of the second plurality of regions 612 based on the transmission characteristics exhibited by overlapping regions of the first plurality of regions 608 and the target values. In an embodiment, the target values ​​are a transmission spectrum T over a wavelength range of 400 nm to 700 nm. target (λ). The reverse transmission spectrum is T target The inverse transmission spectrum can be calculated for each of the second plurality of regions 612 as the ratio of T(λ) / T(λ), where T(λ) is the transmission spectrum associated with the overlapping area of ​​the first plurality of regions 608. The inverse transmission spectrum can then be used to calculate the appropriate ink combination for each of the second plurality of regions 612. In embodiments, the XYZ or RGB values ​​associated with the first plurality of regions 608 can be inverted and multiplied by the target values ​​for those coordinates to calculate the inverse values ​​for the overlapping area of ​​the second plurality of regions 612 in the second ink layer 604.

[0131] In block 806, once the patterns of the first and second ink layers 602 and 604 have been determined, the first and second ink layers 602 and 604 are disposed on the substrate 450 such that the intermediate layer 600 is disposed between the first and second ink layers 602 and 604. In block 808, the light source 540 is attached to the substrate 450. The deposition of the first and second ink layers 602 and 604 and the attachment of the light source 540 can take a variety of forms, depending on the implementation. For example, in embodiments, the intermediate layer 600 includes a second substrate 607. The intermediate layer 600 can, in some embodiments, consist of, or consist essentially of, the second substrate 607 (such that the second substrate 607 is a monolith formed from the same material, which may be of a homogeneous composition or a composite). In such embodiments, one or more of the first and second ink layers 602 and 604 are deposited on the second substrate 607 before attachment to the substrate 450. The first and second ink layers 602 and 604 can, for example, be inkjet printed on both sides of the second substrate 607, which can then be laminated to the light source 540 and then attached to the substrate 450. In embodiments, the first ink layer 602 is printed directly on the substrate 450 and the second ink layer is printed directly on a surface of the second substrate 607 (e.g., a surface of the second substrate 607 further from the substrate 450). The second substrate can be laminated to the light source 540 and then attached to the light source 540.

[0132] In embodiments, the intermediate layer 600 further includes a reflective layer 609 disposed on the second substrate 607. The reflective layer 609 can be a metal layer or a stack of alternating high or low refractive index materials, as described herein. Thus, in such embodiments, the method 800 can include depositing the reflective layer 609 on the second substrate 607 before depositing the first and second ink layers 602 and 604 thereon. In embodiments, the second ink layer 604 can be deposited on a third substrate (not shown) below the reflective layer 609, and the third substrate can be laminated to the light source 540 and then attached to the second substrate 607 and substrate 450.

[0133] In embodiments, the intermediate layer 600 includes an ink layer (e.g., a diffuse white or gray ink or a metallic ink) disposed between the first and second ink layers 602 and 604. In such embodiments, the first and second ink layers 602 and 604 and the intermediate layer 600 can be disposed on the same substrate. For example, the first and second ink layers 602 and 604 and the intermediate layer 600 can be disposed on the substrate 450 in direct contact with each other. In embodiments, at least one of the first ink layer 602 and the intermediate layer 600 is printed on the substrate 450, while the second ink layer 604 is printed on the second substrate 607. In embodiments, the intermediate layer 600 includes an air gap disposed between the first ink layer 602 and the second ink layer 604. In such an embodiment, attaching the light source 540 to the substrate 450 may include laminating a second substrate 607 (including a second ink layer 604 printed thereon) to the light source 540, and attaching the light source 540 and the second substrate 607 to the substrate 450 having the support structure 605 such that the second ink layer 604 is held in a spaced apart relationship relative to the substrate 450 to form an air gap.

[0134] Glass Materials 7 , in embodiments, the substrate 450 has a thickness t that is substantially constant across the width and length of the substrate 450 and is defined as the distance between the first major surface 470 and the second major surface 480. In various embodiments, t may refer to the average thickness or maximum thickness of the substrate 450. Additionally, the substrate 450 has a width W, defined as a first largest dimension of one of the first or second major surfaces 470, 480 perpendicular to the thickness t, and a length L, defined as a second largest dimension of one of the first or second major surfaces 470, 480 perpendicular to both the thickness and width. In other embodiments, W and L may be the average width and average length, respectively, of the substrate 450, and in other embodiments, W and L may be the maximum width and maximum length, respectively, of the substrate 450 (e.g., for glass substrates having variable widths or lengths).

[0135] In various embodiments, the thickness t is 2 mm or less. Specifically, the thickness t is 0.30 mm to 2.0 mm. For example, the thickness t may be 0.30 mm to about 2.0 mm, about 0.40 mm to about 2.0 mm, about 0.50 mm to about 2.0 mm, about 0.60 mm to about 2.0 mm, about 0.70 mm to about 2.0 mm, about 0.80 mm to about 2.0 mm, about 0.90 mm to about 2.0 mm, about 1.0 mm to about 2.0 mm, about 1.1 mm to about 2.0 mm, about 1.2 mm to about 2.0 mm, about 1.3 mm to about 2.0 mm, about 1.4 mm to about 2.0 mm, about 1.5 mm to about 2.0 mm, about 0.30 mm to about 1.9 mm, about 0.30 mm to about 1.8 mm, In other embodiments, t may be in the range of about 0.30 mm to about 1.7 mm, about 0.30 mm to about 1.6 mm, about 0.30 mm to about 1.5 mm, about 0.30 mm to about 1.4 mm, about 0.30 mm to about 1.4 mm, about 0.30 mm to about 1.3 mm, about 0.30 mm to about 1.2 mm, about 0.30 mm to about 1.1 mm, about 0.30 mm to about 1.0 mm, about 0.30 mm to about 0.90 mm, about 0.30 mm to about 0.80 mm, about 0.30 mm to about 0.70 mm, about 0.30 mm to about 0.60 mm, or about 0.30 mm to about 0.40 mm. In other embodiments, t falls within any one of the exact numerical ranges recited in this paragraph.

[0136] In various embodiments, the width W is from 5 cm to 250 cm, from about 10 cm to about 250 cm, from about 15 cm to about 250 cm, from about 20 cm to about 250 cm, from about 25 cm to about 250 cm, from about 30 cm to about 250 cm, from about 35 cm to about 250 cm, from about 40 cm to about 250 cm, from about 45 cm to about 250 cm, from about 50 cm to about 250 cm, from about 55 cm to about 250 cm, from about 60 cm to about 250 cm, from about 65 cm to about 250 cm, from about 70 cm to about 250 cm, from about 75 cm to about 250 cm, from about 80 cm to about 250 cm, from about 85 cm to about 250 cm, from about 90 cm to about 250 cm, from about 95 cm to about 250 cm, from about 100 cm to about 250 cm, from about 110 cm to about 250 cm, The length may range from 120 cm to about 250 cm, from about 130 cm to about 250 cm, from about 140 cm to about 250 cm, from about 150 cm to about 250 cm, from about 5 cm to about 240 cm, from about 5 cm to about 230 cm, from about 5 cm to about 220 cm, from about 5 cm to about 210 cm, from about 5 cm to about 200 cm, from about 5 cm to about 190 cm, from about 5 cm to about 180 cm, from about 5 cm to about 170 cm, from about 5 cm to about 160 cm, from about 5 cm to about 150 cm, from about 5 cm to about 140 cm, from about 5 cm to about 130 cm, from about 5 cm to about 120 cm, from about 5 cm to about 110 cm, from about 5 cm to about 110 cm, from about 5 cm to about 100 cm, from about 5 cm to about 90 cm, from about 5 cm to about 80 cm, or from about 5 cm to about 75 cm. In other embodiments, W falls within any one of the exact numerical ranges recited in this paragraph.

[0137] In various embodiments, the length L is from about 5 cm to about 2500 cm, from about 5 cm to about 2000 cm, from about 4 cm to about 1500 cm, from about 50 cm to about 1500 cm, from about 100 cm to about 1500 cm, from about 150 cm to about 1500 cm, from about 200 cm to about 1500 cm, from about 250 cm to about 1500 cm, from about 300 cm to about 1500 cm, from about 350 cm to about 1500 cm, from about 400 cm to about 1500 cm, from about 450 cm to about 1500 cm, from about 500 cm to about 1500 cm, from about 550 cm to about 1500 cm, from about 600 cm to about 1500 cm, from about 650 cm to about 1500 cm, from about 650 cm to about 1500 cm, cm, about 700 cm to about 1500 cm, about 750 cm to about 1500 cm, about 800 cm to about 1500 cm, about 850 cm to about 1500 cm, about 900 cm to about 1500 cm, about 950 cm to about 1500 cm, about 1000 cm to about 1500 cm, about 1050 cm to about 1500 cm, about 1100 cm to about 1500 cm, about 1150 cm to about 1500 cm, about 1200 cm to about 1500 cm, about 1250 cm to about 1500 cm, about 1300 cm to about 1500 cm, about 1350 cm to about 1500 cm, about 1400 cm to about 1500 cm, or about 1450 cm to about 1500 cm. In other embodiments, L falls within any one of the exact numerical ranges recited in this paragraph.

[0138] In embodiments, the various glass layers of the decorative glasses described herein, such as substrate 450, may be formed from any suitable glass composition, including soda-lime glass, aluminosilicate glass, borosilicate glass, aluminoborosilicate glass, alkali-containing aluminosilicate glass, alkali-containing borosilicate glass, and alkali-containing aluminoborosilicate glass.

[0139] Unless otherwise specified, the glass compositions disclosed herein are listed in mole percent (mol%) as analyzed on an oxide basis.

[0140] In one or more embodiments, the glass composition may include SiO in an amount in the range from about 66 mol% to about 80 mol%, about 67 mol% to about 80 mol%, about 68 mol% to about 80 mol%, about 69 mol% to about 80 mol%, about 70 mol% to about 80 mol%, about 72 mol% to about 80 mol%, about 65 mol% to about 78 mol%, about 65 mol% to about 76 mol%, about 65 mol% to about 75 mol%, about 65 mol% to about 74 mol%, about 65 mol% to about 72 mol%, or about 65 mol% to about 70 mol%, and all ranges and sub-ranges therebetween.

[0141] In one or more embodiments, the glass composition includes Al2O3 in an amount greater than about 4 mol%, or greater than about 5 mol%. In one or more embodiments, the glass composition includes Al2O3 in a range from greater than about 7 mol% to about 15 mol%, from greater than about 7 mol% to about 14 mol%, from about 7 mol% to about 13 mol%, from about 4 mol% to about 12 mol%, from about 7 mol% to about 11 mol%, from about 8 mol% to about 15 mol%, from 9 mol% to about 15 mol%, from about 9 mol% to about 15 mol%, from about 10 mol% to about 15 mol%, from about 11 mol% to about 15 mol%, or from about 12 mol% to about 15 mol%, and all ranges and sub-ranges therebetween. In one or more embodiments, the upper limit of Al2O3 can be about 14 mol%, 14.2 mol%, 14.4 mol%, 14.6 mol%, or 14.8 mol%.

[0142] In one or more embodiments, the glass layer herein is described as being made as an aluminosilicate glass article or from an aluminosilicate glass composition. In such embodiments, the glass composition or article formed therefrom comprises SiO and AlO and is not a soda-lime silicate glass. In that regard, the glass composition or article formed therefrom comprises AlO in an amount of about 2 mol% or more, 2.25 mol% or more, 2.5 mol% or more, about 2.75 mol% or more, or about 3 mol% or more.

[0143] In one or more embodiments, the glass composition includes B2O3 (e.g., about 0.01 mol% or more). In one or more embodiments, the glass composition includes B2O3 in an amount ranging from about 0 mol% to about 5 mol%, from about 0 mol% to about 4 mol%, from about 0 mol% to about 3 mol%, from about 0 mol% to about 2 mol%, from about 0 mol% to about 1 mol%, from about 0 mol% to about 0.5 mol%, from about 0.1 mol% to about 5 mol%, from about 0.1 mol% to about 4 mol%, from about 0.1 mol% to about 3 mol%, from about 0.1 mol% to about 2 mol%, from about 0.1 mol% to about 1 mol%, from about 0.1 mol% to about 0.5 mol%, and all ranges and sub-ranges therebetween. In one or more embodiments, the glass composition is substantially free of B2O3.

[0144] As used herein, the phrase "substantially free" with respect to a component of a composition means that the component is not actively or intentionally added to the composition during initial batch formulation, but may be present as an impurity in an amount less than about 0.001 mole percent.

[0145] In one or more embodiments, the glass composition optionally includes P2O5 (e.g., about 0.01 mol% or more). In one or more embodiments, the glass composition includes P2O5 in a non-zero amount of up to 2 mol%, up to 1.5 mol%, up to 1 mol%, or up to 0.5 mol%. In one or more embodiments, the glass composition is substantially free of P2O5.

[0146] In one or more embodiments, the glass composition may include R2O (the sum of alkali metal oxides, such as Li2O, Na2O, KO, Rb2O, and Cs2O) in a total amount of about 8 mol% or greater, about 10 mol% or greater, or about 12 mol% or greater. In some embodiments, the glass composition includes R2O in a total amount ranging from about 8 mol% to about 20 mol%, from about 8 mol% to about 18 mol%, from about 8 mol% to about 16 mol%, from about 8 mol% to about 14 mol%, from about 8 mol% to about 12 mol%, from about 9 mol% to about 20 mol%, from about 10 mol% to about 20 mol%, from about 11 mol% to about 20 mol%, from about 12 mol% to about 20 mol%, from about 13 mol% to about 20 mol%, from about 10 mol% to about 14 mol%, or from 11 mol% to about 13 mol%, and all ranges and sub-ranges therebetween. In one or more embodiments, the glass composition may be substantially free of RbO, CsO, or both RbO and CsO. In one or more embodiments, RO may include only the total amount of LiO, NaO, and KO. In one or more embodiments, the glass composition may include at least one alkali metal oxide selected from LiO, NaO, and KO, where the alkali metal oxide is present in an amount of about 8 mol% or greater.

[0147] In one or more embodiments, the glass composition includes NaO in an amount of about 8 mol% or greater, about 10 mol% or greater, or about 12 mol% or greater, hi one or more embodiments, the glass composition includes NaO in an amount of about 8 mol% to about 20 mol%, about 8 mol% to about 18 mol%, about 8 mol% to about 16 mol%, about 8 mol% to about 14 mol%, about 8 mol% to about 12 mol%, about 9 mol% to about 20 mol%, about 10 mol% to about 20 mol%, about 11 mol% to about 20 mol%, about 12 mol% to about 20 mol%, about 13 mol% to about 20 mol%, about 10 mol% to about 14 mol%, or 11 mol% to about 13 mol%, and all ranges and sub-ranges therebetween.

[0148] In one or more embodiments, the glass composition includes less than about 4 mol% K2O, less than about 3 mol% K2O, or less than about 1 mol% K2O. In some cases, the glass composition may include KO in an amount in the range from about 0 mol% to about 4 mol%, from about 0 mol% to about 3.5 mol%, from about 0 mol% to about 3 mol%, from about 0 mol% to about 2.5 mol%, from about 0 mol% to about 2 mol%, from about 0 mol% to about 1.5 mol%, from about 0 mol% to about 1 mol%, from about 0 mol% to about 0.5 mol%, from about 0 mol% to about 0.2 mol%, from about 0 mol% to about 0.1 mol%, from about 0.5 mol% to about 4 mol%, from about 0.5 mol% to about 3.5 mol%, from about 0.5 mol% to about 3 mol%, from about 0.5 mol% to about 2.5 mol%, from about 0.5 mol% to about 2 mol%, from about 0.5 mol% to about 1.5 mol%, or from about 0.5 mol% to about 1 mol%, and all ranges and sub-ranges therebetween. In one or more embodiments, the glass composition is substantially free of K2O.

[0149] In one or more embodiments, the glass composition is substantially free of Li2O.

[0150] In one or more embodiments, the amount of Na2O in the composition may be greater than the amount of Li2O. In some cases, the amount of Na2O may be greater than the combined amount of Li2O and K2O. In one or more alternative embodiments, the amount of Li2O in the composition may be greater than the amount of Na2O or the combined amount of Na2O and K2O.

[0151] In one or more embodiments, the glass composition may include RO (which is the sum of alkaline earth metal oxides, such as CaO, MgO, BaO, ZnO, and SrO) in a total amount ranging from about 0 mol% to about 2 mol%. In some embodiments, the glass composition includes RO in a non-zero amount up to about 2 mol%. In one or more embodiments, the glass composition includes RO in an amount from about 0 mol% to about 1.8 mol%, from about 0 mol% to about 1.6 mol%, from about 0 mol% to about 1.5 mol%, from about 0 mol% to about 1.4 mol%, from about 0 mol% to about 1.2 mol%, from about 0 mol% to about 1 mol%, from about 0 mol% to about 0.8 mol%, from about 0 mol% to about 0.5 mol%, and all ranges and sub-ranges therebetween.

[0152] In one or more embodiments, the glass composition includes CaO in an amount less than about 1 mol%, less than about 0.8 mol%, or less than about 0.5 mol%. In one or more embodiments, the glass composition is substantially free of CaO. In some embodiments, the glass composition includes MgO in an amount from about 0 mol% to about 7 mol%, from about 0 mol% to about 6 mol%, from about 0 mol% to about 5 mol%, from about 0 mol% to about 4 mol%, from about 0.1 mol% to about 7 mol%, from about 0.1 mol% to about 6 mol%, from about 0.1 mol% to about 5 mol%, from about 0.1 mol% to about 4 mol%, from about 1 mol% to about 7 mol%, from about 2 mol% to about 6 mol%, or from about 3 mol% to about 6 mol%, and all ranges and sub-ranges therebetween.

[0153] In one or more embodiments, the glass composition includes ZrO in an amount of about 0.2 mol% or less, about 0.18 mol% or less, about 0.16 mol% or less, about 0.15 mol% or less, about 0.14 mol% or less, or about 0.12 mol% or less. In one or more embodiments, the glass composition includes ZrO in an amount of about 0.01 mol% to about 0.2 mol%, about 0.01 mol% to about 0.18 mol%, about 0.01 mol% to about 0.16 mol%, about 0.01 mol% to about 0.15 mol%, about 0.01 mol% to about 0.14 mol%, about 0.01 mol% to about 0.12 mol%, or about 0.01 mol% to about 0.10 mol%, and all ranges and sub-ranges therebetween.

[0154] In one or more embodiments, the glass composition includes SnO in an amount of about 0.2 mol% or less, about 0.18 mol% or less, about 0.16 mol% or less, about 0.15 mol% or less, about 0.14 mol% or less, or about 0.12 mol% or less. In one or more embodiments, the glass composition includes SnO in an amount of about 0.01 mol% to about 0.2 mol%, about 0.01 mol% to about 0.18 mol%, about 0.01 mol% to about 0.16 mol%, about 0.01 mol% to about 0.15 mol%, about 0.01 mol% to about 0.14 mol%, about 0.01 mol% to about 0.12 mol%, or about 0.01 mol% to about 0.10 mol%, and all ranges and sub-ranges therebetween.

[0155] In one or more embodiments, the glass composition may include oxides that impart color or tint to the glass article. In some embodiments, the glass composition includes oxides that prevent discoloration of the glass article when exposed to ultraviolet light. Examples of such oxides include, without limitation, oxides of Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Ce, W, and Mo.

[0156] In one or more embodiments, the glass composition includes Fe, expressed as Fe2O3, where Fe is present in an amount up to and including about 1 mol%. In some embodiments, the glass composition is substantially free of Fe. In one or more embodiments, the glass composition includes Fe2O3 in an amount of about 0.2 mol% or less, about 0.18 mol% or less, about 0.16 mol% or less, about 0.15 mol% or less, about 0.14 mol% or less, or about 0.12 mol% or less. In one or more embodiments, the glass composition includes Fe2O3 in the range from about 0.01 mol% to about 0.2 mol%, from about 0.01 mol% to about 0.18 mol%, from about 0.01 mol% to about 0.16 mol%, from about 0.01 mol% to about 0.15 mol%, from about 0.01 mol% to about 0.14 mol%, from about 0.01 mol% to about 0.12 mol%, or from about 0.01 mol% to about 0.10 mol%, and all ranges and sub-ranges therebetween.

[0157] When the glass composition includes TiO2, TiO2 may be present in an amount of about 5 mol% or less, about 2.5 mol% or less, about 2 mol% or less, or about 1 mol% or less. In one or more embodiments, the glass composition may be substantially free of TiO2.

[0158] Exemplary glass compositions include SiO in an amount ranging from about 65 mol% to about 75 mol%, AlO in an amount ranging from about 8 mol% to about 14 mol%, NaO in an amount ranging from about 12 mol% to about 17 mol%, KO in an amount ranging from about 0 mol% to about 0.2 mol%, and MgO in an amount ranging from about 1.5 mol% to about 6 mol%. Optionally, SnO may be included in amounts as otherwise disclosed herein.

[0159] Properties of tempered glass In one or more embodiments, the substrate 450 described herein may be formed from a tempered glass sheet or article. In one or more embodiments, the glass articles used to form the layers of the decorative glass structures described herein may be tempered to have compressive stresses extending from the surface to a depth of compression (DOC). The compressive stress areas are balanced by a central portion that exhibits tensile stress. At the DOC, the stress crosses from positive (compressive) to negative (tensile).

[0160] In one or more embodiments, the glass articles used to form the layers of the decorative glass structures described herein may be mechanically strengthened by exploiting the mismatch in thermal expansion coefficients between portions of the glass to create regions of compressive stress and a central region exhibiting tensile stress. In some embodiments, the glass article may be thermally strengthened by heating the glass above its glass transition temperature and then quenching.

[0161] In one or more embodiments, the glass articles used to form the layers of the decorative glass structures described herein may be chemically strengthened by ion exchange. In the ion exchange process, ions at or near the surface of the glass article are replaced—i.e., exchanged—with larger ions having the same valence or oxidation state. In embodiments where the glass article is made from an alkali aluminosilicate glass, the ions in the surface layer of the article and the larger ions are Li + , Na + , K. + , Rb + , and Cs + Alternatively, the monovalent cations in the surface layer are Ag + In such embodiments, stress is induced in the glass article by the monovalent ions (or cations) that are exchanged.

[0162] The ion exchange process is typically carried out by immersing the glass article in a molten salt bath (or two or more molten salt baths) containing the larger ions to be exchanged for the smaller ions in the glass article. It should be noted that aqueous salt baths may also be utilized. Additionally, the bath composition may contain multiple types of larger ions (e.g., Na + and K. + ) or one larger ion. Those skilled in the art will recognize that the parameters of the ion exchange process, including but not limited to the bath composition and temperature, immersion time, number of immersions of the glass article in the salt bath, use of multiple salt baths, and additional steps such as annealing, washing, etc., will generally depend on the composition of the glass layer of the decorative glass structure (including the structure of the article and any crystalline phases present), and the desired DOC and CS of the glass layer of the decorative glass structure resulting from tempering.

[0163] Exemplary molten bath compositions may include nitrates, sulfates, and chlorides of larger alkali metal ions. Typical nitrates include KNO, NaNO, LiNO, NaSO, and combinations thereof. Molten salt bath temperatures generally range from about 380°C to about 450°C, while immersion times range from about 15 minutes to about 100 hours, depending on the glass thickness, bath temperature, and diffusivity of the glass (or monovalent ions). However, temperatures and immersion times different from those described above may also be used.

[0164] According to one or more embodiments, a glass article used to form a layer of decorative glass may be immersed in a molten salt bath of 100% NaNO, 100% KNO, or a combination of NaNO and KNO, having a temperature of about 370° C. to about 480° C. In some embodiments, the glass layer of the decorative glass may be immersed in a molten mixed salt bath containing about 5% to about 90% KNO and about 10% to about 95% NaNO. In some embodiments, the glass article may be immersed in a first bath followed by a second bath. The first and second baths may have different compositions and / or temperatures. The immersion times in the first and second baths may vary. For example, the immersion in the first bath may be longer than the immersion in the second bath.

[0165] According to one or more embodiments, the glass article used to form the layers of the decorative glass structure may be immersed in a molten mixed salt bath comprising NaNO and KNO (e.g., 49% / 51%, 50% / 50%, 51% / 49%) having a temperature of less than about 420°C (e.g., about 400°C or about 380°C) for less than about 5 hours, or even about 4 hours or less.

[0166] The ion exchange conditions can be tailored to increase the gradient, or "spike," of the stress profile at or near the surface of the resulting glass layer of the decorative glass structure. The spike will result in a larger surface CS value. This spike can be achieved by a single bath or multiple baths, with a single composition or a mixture of compositions due to the unique properties of the glass compositions used in the glass layers of the decorative glass structures described herein.

[0167] In one or more embodiments in which multiple monovalent ions are exchanged into a glass article used to form a layer of a decorative glass structure, different monovalent ions may be exchanged to different depths within the glass layer (producing different magnitudes of stress within the glass article at different depths), and the resulting relative depths of the stress-producing ions can be determined, thereby producing different characteristics of the stress profile.

[0168] CS is measured using means known in the art, such as by a surface stress meter (FSM) using commercially available equipment, such as the FSM-6000 manufactured by Orihara Seisakusho Co., Ltd. (Japan). Surface stress measurements rely on precise measurement of the stress optical coefficient (SOC), which is related to the birefringence of the glass. SOC is then measured by methods known in the art, such as the fiber method and the four-point bending method, both of which are described in ASTM Standard C770-98 (2013), entitled "Standard Test Method for Measurement of Glass Stress-Optical Coefficient," and the bulk cylinder method, the contents of which are incorporated herein by reference in their entirety. As used herein, CS may be the "maximum compressive stress," which is the highest compressive stress value measured within the compressive stress layer. In some embodiments, the maximum compressive stress is located at the surface of the glass article. In other embodiments, the maximum compressive stress may occur at a depth below the surface, giving the compressive profile the appearance of a "buried peak."

[0169] The DOC can be measured by FSM or by a scattered light polarimeter (SCALP) (such as the SCALP-04 scattered light polarimeter available from GlassStress Ltd., Tallinn, Estonia). If the glass article is chemically strengthened by an ion exchange process, either the FSM or the SCALP can be used, depending on which ions are exchanged into the glass article. If the stress in the glass article is induced by exchanging potassium ions into the glass article, the FSM is used to measure the DOC. If the stress in the glass article is induced by exchanging sodium ions into the glass article, the SCALP is used to measure the DOC. If the stress in the glass article is induced by exchanging both potassium and sodium ions into the glass article, the DOC is measured by SCALP. Because the exchange depth of the sodium ions is considered to represent the DOC, and the exchange depth of the potassium ions is considered to represent the change in the magnitude of compressive stress (not the change from compressive to tensile stress), the exchange depth of the potassium ions in such glass articles is measured by FSM. The central tension or CT is the maximum tensile stress and is measured by SCALP.

[0170] In one or more embodiments, the glass articles used to form the layers of the decorative glass structure may be strengthened to exhibit a DOC, expressed as a percentage of the thickness t (as described herein) of the glass article. For example, in one or more embodiments, the DOC may be about 0.05t or greater, about 0.1t or greater, about 0.11t or greater, about 0.12t or greater, about 0.13t or greater, about 0.14t or greater, about 0.15t or greater, about 0.16t or greater, about 0.17t or greater, about 0.18t or greater, about 0.19t or greater, about 0.2t or greater, or about 0.21t or greater. In some embodiments, the DOC may be in the range of about 0.08t to 0.25t, about 0.09t to 0.25t, about 0.18t to 0.25t, about 0.11t to 0.25t, about 0.12t to 0.25t, about 0.13t to 0.25t, about 0.14t to 0.25t, about 0.15t to 0.25t, about 0.08t to 0.24t, about 0.08t to 0.23t, about 0.08t to 0.22t, about 0.08t to 0.21t, about 0.08t to 0.2t, about 0.08t to 0.19t, about 0.08t to 0.18t, about 0.08t to 0.17t, about 0.08t to 0.16t, or about 0.08t to 0.15t. In some cases, the DOC may be about 20 μm or less. In one or more embodiments, the DOC may be about 40 μm or more (e.g., about 40 μm to about 300 μm, about 50 μm to about 300 μm, about 60 μm to about 300 μm, about 70 μm to about 300 μm, about 80 μm to about 300 μm, about 90 μm to about 300 μm, about 100 μm to about 300 μm, about 110 μm to about 300 μm, about 120 μm to about 300 μm, about 140 μm to about 300 μm, about 150 μm to about 300 μm, about 40 μm to about 290 μm, about 40 μm to about 280 μm, about 40 μm to about 260 μm, about 40 μm to about 250 μm, about 40 μm to about 240 μm, about 40 μm to about 230 μm, about 40 μm to about 220 μm, about 40 μm to about 210 μm, about 40 μm to about 200 μm, about 40 μm to about 180 μm, about 40 μm to about 160 μm, about 40 μm to about 150 μm, about 40 μm to about 140 μm, about 40 μm to about 130 μm, about 40 μm to about 120 μm, about 40 μm to about 110 μm, or about 40 μm to about 100 μm).

[0171] In one or more embodiments, the glass article used to form the layers of the decorative glass structure may have a CS (which may be found on the surface or deep within the glass article) of about 200 MPa or greater, 300 MPa or greater, 400 MPa or greater, about 500 MPa or greater, about 600 MPa or greater, about 700 MPa or greater, about 800 MPa or greater, about 900 MPa or greater, about 930 MPa or greater, about 1000 MPa or greater, or about 1050 MPa or greater.

[0172] In one or more embodiments, the glass articles used to form the layers of the decorative glass structure may have a maximum tensile stress or central tension (CT) of about 20 MPa or greater, about 30 MPa or greater, about 40 MPa or greater, about 45 MPa or greater, about 50 MPa or greater, about 60 MPa or greater, about 70 MPa or greater, about 75 MPa or greater, about 80 MPa or greater, or about 85 MPa or greater. In some embodiments, the maximum tensile stress or central tension (CT) may be in the range of about 40 MPa to about 100 MPa.

[0173] Unless otherwise expressly stated, it is in no way intended that any method set forth herein be construed as requiring that its steps be performed in a particular order. Thus, unless a method claim actually recites the order in which its steps should be followed, or unless the claim or description specifically states otherwise that the steps are to be limited to a particular order, no particular order is intended to be implied. Additionally, as used herein, nouns are intended to include one or more components or elements and are not intended to be construed to mean just one.

[0174] It will be apparent to those skilled in the art that various modifications and variations can be made without departing from the spirit or scope of the disclosed embodiments. Since modifications, combinations, sub-combinations, and variations of the disclosed embodiments that incorporate the spirit and substance of the embodiments will occur to those skilled in the art, the disclosed embodiments should be construed as including all within the scope of the appended claims and equivalents thereof.

[0175] Preferred embodiments of the present invention will be described below in detail.

[0176] Embodiment 1 In dead-front items, a substrate having a first major surface and a second major surface opposite the first major surface; a dead front assembly disposed on the second major surface, a first ink layer disposed adjacent to the second major surface; an intermediate layer positioned such that the first ink layer is disposed between the intermediate layer and the second major surface; a second ink layer positioned such that the intermediate layer is disposed between the second ink layer and the first ink layer; Including, the intermediate layer exhibits an average reflectance of 1.0% or greater over a wavelength range of 400 nm to 700 nm for light initially incident on the surface of the intermediate layer closest to the substrate; the first ink layer includes a first plurality of regions; the second ink layer includes a second plurality of regions; a dead-front assembly, wherein each region of the second plurality of regions is configured to inhibit deviation of an appearance of an overlapping region of the first plurality of regions from a target optical appearance in transmission; Dead front items with.

[0177] Embodiment 2 2. The deadfront article of claim 1, wherein each region of the second plurality of regions has tristimulus X, Y, and Z values ​​according to CIE 1931 color space calculated as a ratio of a target value to the tristimulus X, Y, and Z values ​​of an overlapping region of the first plurality of regions, each of the target values ​​being greater than or equal to 0.30 and less than or equal to 0.50.

[0178] Embodiment 3 When light from a D65 light source is transmitted through the dead front article, the light has a maximum L of 50 or more and 80 or less. * 2. The dead-front article of embodiment 1, exhibiting a value.

[0179] Embodiment 4 When light from a D65 light source is transmitted through the dead front article, the light has a maximum a * value and the maximum b between -5 and 5 * 4. The dead-front article of embodiment 3, exhibiting a value.

[0180] Embodiment 5 A dead front article as described in embodiment 3 or 4, wherein when light from a D65 light source is transmitted through the dead front article, the light exhibits a maximum ΔE value calculated using the CIE76 formula between two different positions on the dead front article that is 5.0 or less.

[0181] Embodiment 6 6. The deadfront article of embodiment 5, wherein the maximum ΔE value is 2.0 or less.

[0182] Embodiment 7 7. A dead-front article as described in any one of claims 1 to 6, wherein each overlapping pair of regions comprising one of the first plurality of regions and one of the second plurality of regions exhibits a tristimulus Y value of 0.3 or greater and 0.5 or less when light from a light source is transmitted through the dead-front assembly.

[0183] Embodiment 8 8. The deadfront article of any one of the preceding claims, wherein the intermediate layer has a refractive index of 1.8 or greater or 1.2 or less.

[0184] Embodiment 9 9. The deadfront article of any one of the preceding claims, wherein the intermediate layer comprises at least one of a clear ink, a white ink, or a gray ink.

[0185] Embodiment 10 9. The deadfront article of any one of the preceding claims, wherein the intermediate layer comprises a metal layer.

[0186] Embodiment 11 the intermediate layer includes a gap between the first ink layer and the second ink layer, the second ink layer being disposed on a surface of a second substrate held in fixed relationship to the substrate; 9. The deadfront article of any one of embodiments 1 to 8.

[0187] Embodiment 12 the intermediate layer has a refractive index of 1.8 or more and includes at least one of Nb2O5, Ta2O5, ZrO2, HfO2, Si3N4, SiON, Y2O3, TiO2, and a transparent conductive oxide; the first ink layer is disposed adjacent to a first surface of the intermediate layer adjacent to the substrate; the second ink layer is disposed directly on the second surface of the intermediate layer; 9. The deadfront article of any one of embodiments 1 to 8.

[0188] Embodiment 13 the intermediate layer comprises a multilayer stack comprising alternating layers of one or more high refractive index materials and one or more low refractive index materials; said multi-layer stack comprising 2 to 20 of said alternating layers; the one or more low refractive index materials have a refractive index of less than 1.6 at 550 nm; the one or more high refractive index materials have a refractive index greater than 1.6 at 550 nm; 9. The deadfront article of any one of embodiments 1 to 8.

[0189] Embodiment 14 9. A dead-front article as described in any one of claims 1 to 8, wherein the intermediate layer comprises an electrochromic layer configured to change between a first light transmission state and a second light transmission state, and the average transmittance of the intermediate layer over the wavelength range is lower in the first light transmission state.

[0190] Embodiment 15 the intermediate layer includes a second substrate and a reflective layer disposed on a surface of the second substrate adjacent to one of the first ink layer and the second ink layer; the first ink layer is disposed on a first surface of the second substrate adjacent to the substrate; the second ink layer is disposed on a second surface of the second substrate; 8. The deadfront article of any one of embodiments 1 to 7.

[0191] Embodiment 16 In the display assembly, a substrate having a first major surface and a second major surface opposite the first major surface; a dead front assembly disposed on the second major surface, a first ink layer disposed adjacent to the second major surface; an intermediate layer positioned such that the first ink layer is disposed between the intermediate layer and the second major surface; a second ink layer positioned such that the intermediate layer is disposed between the second ink layer and the first ink layer; a dead front assembly, including a light source coupled to the substrate such that the dead-front assembly is disposed between the light source and the substrate; Equipped with the light source is configured to emit light having an illumination spectrum spanning a wavelength range of 400 nm to 700 nm that is initially incident on the second ink layer before transmitting through the intermediate layer, the first ink layer, and the substrate; the intermediate layer exhibits an average reflectance of 1.0% or greater over a range of wavelengths for light initially incident on a surface of the intermediate layer closest to the substrate; the first ink layer includes a first plurality of regions; the second ink layer includes a second plurality of regions; Each region of the second plurality of regions has an L in transmission of 50 or greater and 80 or less when the light source emits light at the white point of the light source. * a value, greater than or equal to -5.0 and less than or equal to 5.0 * value, and b between -5.0 and 5.0 * and constraining deviation of an appearance of an overlapping region of the first plurality of regions from a target optical appearance so as to indicate a value.

[0192] Embodiment 17 17. The display assembly of embodiment 16, wherein the light source comprises a display laminated to the substrate, the display comprising one of a liquid crystal display, an organic light emitting diode display, a μLED display, a quantum dot display, and a laser display.

[0193] Embodiment 18 18. A display assembly as described in embodiment 16 or 17, wherein when the light source emits light at the white point of the light source, the dead-front article exhibits a first maximum ΔE value, calculated using the CIE 76 formula, between two different positions of the dead-front article that is 5.0 or less.

[0194] Embodiment 19 19. The display assembly of embodiment 18, wherein the first maximum ΔE value is 2.0 or less.

[0195] Embodiment 20 The light source is transmitted through the dead-front article, and the target L * Value, target a * Values, and goals * When the dead front article emits light having a target L value of 5.0 or less, * , a * , and b * value and the measured L * , a * , and b * 17. The display assembly of embodiment 16, wherein the display assembly exhibits a second maximum ΔE value, calculated using the CIE 76 formula, between 0.25 and 0.35.

[0196] Embodiment 21 21. The display assembly of embodiment 20, wherein the second maximum ΔE value is 2.0 or less.

[0197] Embodiment 22 22. The display assembly of any one of embodiments 16 to 21, wherein the intermediate layer has a refractive index greater than or equal to 1.8 or less than or equal to 1.2.

[0198] Embodiment 23 23. The display assembly of any one of embodiments 16 to 22, wherein the intermediate layer comprises at least one of a clear ink, a white ink, or a gray ink.

[0199] Embodiment 24 23. The display assembly of any one of embodiments 16 to 22, wherein the intermediate layer comprises a metal layer.

[0200] Embodiment 25 the intermediate layer includes a gap between the first ink layer and the second ink layer, the second ink layer being disposed on a surface of a second substrate held in fixed relationship to the substrate; 23. A display assembly according to any one of embodiments 16 to 22.

[0201] Embodiment 26 the intermediate layer has a refractive index of 1.8 or more and includes at least one of Nb2O5, Ta2O5, ZrO2, HfO2, Si3N4, SiON, Y2O3, TiO2, and a transparent conductive oxide; the first ink layer is disposed adjacent to a first surface of the intermediate layer adjacent to the substrate; the second ink layer is disposed directly on the second surface of the intermediate layer; 23. A display assembly according to any one of embodiments 16 to 22.

[0202] Embodiment 27 the intermediate layer comprises a multilayer stack comprising alternating layers of one or more high refractive index materials and one or more low refractive index materials; said multi-layer stack comprising 2 to 20 of said alternating layers; the one or more low refractive index materials have a refractive index of less than 1.6 at 550 nm; the one or more high refractive index materials have a refractive index greater than 1.6 at 550 nm; 23. A display assembly according to any one of embodiments 16 to 22.

[0203] Embodiment 28 23. A display assembly as described in any one of embodiments 16 to 22, wherein the intermediate layer includes an electrochromic layer configured to change between a first light transmission state and a second light transmission state, and the average transmittance of the intermediate layer over the wavelength range is lower in the first light transmission state.

[0204] Embodiment 29 the intermediate layer includes a second substrate and a reflective layer disposed on a surface of the second substrate adjacent to one of the first ink layer and the second ink layer; the first ink layer is disposed on a first surface of the second substrate adjacent to the substrate; the second ink layer is disposed on a second surface of the second substrate; 22. A display assembly according to any one of embodiments 16 to 21.

[0205] Embodiment 30 1. A method of manufacturing a display assembly, comprising: determining a first pattern in a first plurality of regions on the first ink layer; determining a second pattern with a second plurality of regions for the second ink layer, the second plurality of regions configured to suppress deviation of the appearance of the first plurality of regions from a target appearance in transmission; and disposing the second ink layer and the first ink layer on the substrate such that an intermediate layer is disposed between the first ink layer and the second ink layer, the intermediate layer exhibiting an average reflectance of 1.0% or greater over a wavelength range of 400 nm to 700 nm for light initially incident on a surface of the intermediate layer closest to the substrate; A method comprising:

[0206] Embodiment 31 determining the second pattern determining XYZ color coordinate values ​​exhibited by each of the first plurality of regions when a light source emits light through the first ink layer at the white point of the light source; and calculating a ratio of a target XYZ color coordinate value to the XYZ color coordinate value to determine an XYZ color coordinate value for each of the second plurality of regions, the XYZ color coordinate value being equal to or greater than 0.3 and equal to or less than 0.5; 31. The method of embodiment 30, comprising:

[0207] Embodiment 32 31. The method of claim 30, further comprising attaching the substrate, the first ink layer, the intermediate layer, and the second ink layer to a light source such that the light source is configured to emit light having an illumination spectrum transmitted through the second ink layer, the intermediate layer, the first ink layer, and the substrate.

[0208] Embodiment 33 the intermediate layer includes an ink layer printed directly on the first ink layer; the second ink layer is printed directly onto the intermediate layer; attaching the substrate, the first ink layer, the intermediate layer, and the second ink layer to the light source includes laminating the light source to the substrate; 33. The method of embodiment 32.

[0209] Embodiment 34 the intermediate layer includes a gap disposed between the first ink layer and the second ink layer; the second ink layer is printed onto a second substrate held in fixed relationship to the substrate; attaching the substrate, the first ink layer, the intermediate layer, and the second ink layer to a light source; laminating the second substrate to the light source; and attaching the light source and the second substrate to a substrate such that the second ink layer is held in spaced apart relationship relative to the substrate to form the gap; 33. The method of embodiment 32.

[0210] Embodiment 35 the intermediate layer comprises a second substrate; the second ink layer is disposed on a surface of the second substrate; the step of attaching the substrate, the first ink layer, the intermediate layer, and the second ink layer to the light source includes the steps of laminating the second substrate to the light source, and laminating the light source to the substrate such that the second substrate is disposed between the substrate and the light source; 33. The method of embodiment 32.

[0211] Embodiment 36 36. The method of claim 35, wherein the second substrate has a refractive index of 1.8 or greater or 1.2 or less, and the first and second ink layers are disposed directly on a surface of the second substrate.

[0212] Embodiment 37 36. The method of embodiment 35, wherein the second substrate has a refractive index greater than 1.2 and less than 1.8, and the intermediate layer further comprises a reflective layer disposed on a surface of the second substrate.

[0213] Embodiment 38 determining the second pattern determining a first set of RGB values ​​for the first plurality of regions based on light emitted by the light source; calculating a second set of RGB values ​​for the second plurality of regions based on a target RGB value and the first set of RGB values; and converting the second set of RGB values ​​for each of the second plurality of regions to ink combinations for each of the second plurality of regions using a subtractive color model; 38. The method of any one of embodiments 32 to 37, comprising: [Explanation of symbols]

[0214] 100, 200, 300 cabin systems 110 Center console base 120, 220, 320 curved surface 130, 230, 330, 540 displays 210 Dashboard Base 215 Instrument Panel 310 Dashboard handle base 400 Deadfront Items 450 board 460 Dead Front Assembly 470 First principal surface 480 Second main surface 490 Functional surface layer 500 opaque layer 520 Image Area 530 Surrounding Area 540 light source 600 Middle Class 602 First ink layer 603a High refractive index material 603b Low refractive index material 604 Second ink layer 605 Support structure 607 Second board 609 Reflective layer

Claims

1. In dead-front items, a substrate having a first major surface and a second major surface opposite the first major surface; a dead front assembly disposed on the second major surface, a first ink layer disposed adjacent the second major surface; an intermediate layer positioned such that the first ink layer is disposed between the intermediate layer and the second major surface; a second ink layer positioned such that the intermediate layer is disposed between the second ink layer and the first ink layer; Including, the intermediate layer exhibits an average reflectance of 1.0% or greater over a wavelength range of 400 nm to 700 nm for light initially incident on a surface of the intermediate layer closest to the substrate; the first ink layer includes a first plurality of regions; the second ink layer includes a second plurality of regions; a dead-front assembly, each region of the second plurality of regions configured to inhibit deviation of an appearance of an overlapping region of the first plurality of regions from a target optical appearance in transmission; Dead front items with.

2. 2. The deadfront article of claim 1, wherein each region of the second plurality of regions has tristimulus X, Y, and Z values ​​according to CIE 1931 color space calculated as a ratio of a target value to the tristimulus X, Y, and Z values ​​of an overlapping region of the first plurality of regions, each of the target values ​​being greater than or equal to 0.30 and less than or equal to 0.

50.

3. When light from a D65 light source is transmitted through the dead front article, the light has a maximum L of 50 or more and 80 or less. ＊ 10. The deadfront article of claim 1, exhibiting a value.

4. When light from a D65 light source is transmitted through the dead front article, the light has a maximum a ＊ value and a maximum b between -5 and 5 ＊ 4. The deadfront article of claim 3, exhibiting a value.

5. 5. The dead front article of claim 3 or 4, wherein when light from a D65 light source is transmitted through the dead front article, the light exhibits a maximum ΔE value calculated using the CIE 76 formula between two different positions on the dead front article of 5.0 or less.

6. 6. The deadfront article of claim 5, wherein the maximum ΔE value is 2.0 or less.

7. 5. The deadfront article of claim 1, wherein each overlapping pair of regions, each pair including one of the first plurality of regions and one of the second plurality of regions, exhibits a tristimulus Y value of 0.3 or greater and 0.5 or less when light from a light source is transmitted through the deadfront assembly.

8. the intermediate layer includes a gap between the first ink layer and the second ink layer, the second ink layer being disposed on a surface of a second substrate held in fixed relationship to the substrate; A deadfront article according to any one of claims 1 to 4.

9. The intermediate layer has a refractive index of 1.8 or more, and ２ O ５ , Ta ２ O ５ , ZrO ２ , HfO ２ , Si ３ N ４ , SiON, Y ２ O ３ , TiO ２ and a transparent conductive oxide, the first ink layer is disposed adjacent to a first surface of the intermediate layer adjacent to the substrate; the second ink layer is disposed directly on the second surface of the intermediate layer; A deadfront article according to any one of claims 1 to 4.

10. the intermediate layer comprises a multilayer stack comprising alternating layers of one or more high refractive index materials and one or more low refractive index materials; said multi-layer stack comprising 2 to 20 of said alternating layers; the one or more low refractive index materials have a refractive index of less than 1.6 at 550 nm; the one or more high refractive index materials have a refractive index greater than 1.6 at 550 nm; A deadfront article according to any one of claims 1 to 4.

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