CN110998427A

CN110998427A - Laser ablated surface with indicia

Info

Publication number: CN110998427A
Application number: CN201780093653.0A
Authority: CN
Inventors: K·L·吉林斯; M·R·罗斯; D·J·卡缅加; H·A·鲁特恩
Original assignee: Gentex Corp
Current assignee: Gentex Corp
Priority date: 2017-08-10
Filing date: 2017-08-10
Publication date: 2020-04-10
Also published as: WO2019032112A1; DE212017000342U1

Abstract

A product comprising a substrate that is at least partially transparent to visible light. The substrate includes a first surface, an opposing second surface, and a conductive layer disposed on the opposing second surface. The conductive layer has a first ablated region and a second ablated region disposed entirely within and overlapping a portion of the first ablated region. The second ablated region contains selectively visible indicia.

Description

Laser ablated surface with indicia

Technical Field

The present disclosure relates generally to laser ablation methods and products produced by the methods. More particularly, the present disclosure relates to a method for selectively ablating the surface of a tunable mirror or window structure to create a visible pattern when the mirror or window is in a particular state.

Disclosure of Invention

One embodiment relates to an article. The product comprises a first substrate which is at least partially transparent to visible light. The substrate includes a first surface, an opposing second surface, and a first conductive layer disposed on the opposing second surface. The first conductive layer has a first ablated region and a second ablated region disposed entirely within and overlapping a portion of the first ablated region. The second ablated region defines a selectively visible mark.

Another embodiment relates to an electrochromic device. The electrochromic device includes a first substrate, a second substrate, and an electrochromic medium. The first substrate has a first surface and an opposing second surface. The opposing second surface includes a first conductive layer disposed thereon having a first ablation area and a second ablation area disposed entirely within and overlapping a portion of the first ablation area. The first ablation region is formed by subjecting the first conductive layer to a first laser ablation process. Forming the second ablated region by additionally subjecting the portion of the first ablated region to a second laser ablation process. The second substrate is spaced apart from the first substrate to define an interior chamber therebetween. The second substrate has a third surface and an opposing fourth surface. The third surface includes a second conductive layer disposed thereon. The electrochromic medium is disposed within the internal cavity between the first and second conductive layers. The second ablated region is at least partially invisible when the electrochromic medium is in a transparent state. The second ablated region is visible when the electrochromic medium is in a darkened state.

Yet another embodiment relates to a method. The method comprises the following steps: providing a substrate having a first side and an opposing second side, the opposing second side comprising a conductive layer and a coating disposed on the conductive layer; subjecting the substrate to a first laser ablation pass such that the coating is removed from at least a portion of the conductive layer; and subjecting the portion of the substrate to one or more additional laser ablation passes to alter a property of at least a sub-portion of the conductive layer. The sub-portion is entirely contained within an area of the portion of the substrate subjected to the first laser ablation pass such that the one or more additional laser ablation passes do not remove any coating from the conductive layer.

The invention is capable of other embodiments and of being practiced and carried out in various ways. Alternative exemplary embodiments relate to other features and combinations of features as may be set forth herein.

Drawings

The illustrative embodiments will hereinafter be described in conjunction with the appended drawings, where like designations denote like elements.

Fig. 1 is a cross-sectional view of a second surface laser ablation process performed on a workpiece, according to an example embodiment.

FIG. 2 is a detailed cross-sectional view of the workpiece of FIG. 1 according to an exemplary embodiment.

Fig. 3 is a top view of a second surface laser ablation process performed on the workpiece of fig. 1, according to an example embodiment.

Fig. 4 is a cross-sectional view of a second surface laser ablation process performed on the workpiece of fig. 1 a second time in accordance with an exemplary embodiment.

Fig. 5 is a top view of a second surface laser ablation process performed on the workpiece of fig. 4, according to an example embodiment.

Fig. 6 is a front view of a first electrochromic device in a first state according to an example embodiment.

Fig. 7 is a front view of the first electrochromic device of fig. 6 in a second state, according to an example embodiment.

Fig. 8 is a cross-sectional view of the first electrochromic device of fig. 6 in a first state according to an example embodiment.

Fig. 9 is a front view of a second electrochromic device in a first state according to an example embodiment.

Fig. 10 is a front view of the second electrochromic device of fig. 9 in a second state according to an example embodiment.

Fig. 11 is a cross-sectional view of the second electrochromic device of fig. 9 in a first state according to an example embodiment.

Fig. 12 is a graph depicting thickness data regarding differences in thickness of conductive layers of a test substrate relative to a control substrate, according to an example embodiment.

FIG. 13 is a graph depicting resistance data relating to the difference in resistance of a conductive layer of a test substrate relative to a control substrate according to an example embodiment.

Fig. 14 to 16 are respective graphs depicting color data regarding a color change of a conductive layer of a test substrate relative to a control substrate according to an exemplary embodiment.

Detailed Description

Laser ablation processes generally involve the selective removal of material at the surface of a workpiece by directing a laser beam at the workpiece. The laser beam is configured to deliver a controlled amount of energy at a laser spot defined where the laser beam impinges the desired surface. This controlled amount of energy is selected to liquefy, vaporize, or otherwise rapidly expand the surface material at the laser spot to separate it from the workpiece for removal. Laser ablation may be used, for example, to remove at least a portion of one or more coatings from a coated substrate, or to otherwise reshape a surface of a workpiece.

Fig. 1 is a side cross-sectional view of an example of a first laser ablation process performed on a workpiece 10. The workpiece 10 is a coated substrate that includes a substrate 12 and a coating 14. The illustrated process is a second surface ablation process in which the coating 14 is located on a second side 16 of the workpiece 10 opposite a first or strike side 18 of the workpiece 10. The laser beam 100 is provided by a laser source 102 and propagates towards the workpiece 10. In this example, the laser beam 100 is configured with a focal plane at or near the second surface 20 of the substrate 12 that is substantially parallel to the x-y reference plane to define a laser spot 104 at the second surface 20 having a characteristic dimension such as a diameter or width w. In other examples, the focal plane may be spaced from the second surface 20 by an amount greater than 0mm up to about 50 mm. Substrate 12 is at least partially transparent to laser light of a particular wavelength of laser beam 100 such that laser beam 100 passes through the thickness of substrate 12 to second surface 20 where the material of coating 14 absorbs at least some of the energy of laser beam 100 and is thus separated from substrate 12.

In the example of fig. 1, the removed coating material 22 is shown in the form of solid particles. The workpiece 10 may be oriented as shown such that gravity causes the removed material 22 to fall away from the workpiece 10. Optionally, a vacuum source 106 is provided to help direct the removed material 22 away from the workpiece 10. The material 22 being removed may be in vapor or liquid form when initially separated from the substrate 12. The illustrated arrangement may be used to prevent the removed material 22 from being redeposited onto the workpiece 10, which may be problematic with certain first surface ablation processes. Material may also be removed via a spalling process.

To remove material from an area of the workpiece 10 larger than the laser spot 104, the laser beam 100 and/or the workpiece 10 may be moved relative to each other to remove material at a plurality of adjacent and/or overlapping laser spot locations. For example, after a desired amount of material is removed from a first laser spot location, the workpiece 10 and/or the laser beam 100 may be moved to define a second laser spot location to further remove material. Continued movement to multiple adjacent and/or overlapping laser spot locations and corresponding material removal at each location defines a first ablation region 24 of the workpiece 10 from which material has been removed, as shown in the top view of the process in fig. 3, where the intended ablation region 26 is shown in phantom. As shown in fig. 1 and 3, the laser beam 100 is moving relative to the workpiece 10 in the instantaneous process direction a. One or both of the laser beam 100 or the workpiece 10 may be moved to achieve this relative movement. In one example, laser beam 100 is moved or scanned back and forth in the positive and negative x-directions within intended ablation area 26, and laser beam 100 and/or workpiece 10 are indexed in the y-direction each time laser beam 100 reaches edge 28 of intended ablation area 26 until coating 14 is removed throughout intended ablation area 26 (e.g., a non-staggered laser ablation process, etc.). In another example, the laser beam 100 is moved or scanned back and forth within the intended ablation area 26 in positive and negative x-directions, wherein successive laser spots 104 (e.g., adjacent spots, first laser spot, subsequent laser spots, etc.) in the x-direction are physically spaced apart from one another (e.g., do not overlap, etc.), and the laser beam 100 and/or the workpiece 10 are indexed in the y-direction each time the laser beam 100 reaches the edge 28 of the intended ablation area 26. Consecutive laser spots 104 in the y-direction (e.g., adjacent spots, first laser spot, subsequent laser spots, etc.) may also be physically spaced apart from each other (e.g., not overlapping, etc.). Laser beam 100 may undergo multiple passes over intended ablated region 26, each pass at least partially deviating from the previous pass, such that the entire intended ablated region 26 is scanned after the multiple passes (e.g., all desired portions of coating 14 are removed from intended ablated region 26, interleaving the laser ablation process, etc.).

The coating 14 can be formed of nearly any material (e.g., metal, plastic, and/or ceramic) and can be generally more opaque than the substrate 12. Certain metallic materials, such as chromium or chromium-containing materials, may be multifunctional to provide reflectivity, opacity, conductivity, and potentially decorative aspects. In some embodiments, the coating 14 provided for the ablation process is itself a multilayer coating. For example, the coating 14 may include a reflective layer in direct contact with the substrate and a light absorbing layer over the reflective layer to minimize laser reflection during ablation. In other embodiments, some of which are described in further detail below, the workpiece may include additional layers between the substrate 12 and the coating 14. The additional layer may be any suitable material. In some embodiments, the additional layer may be at least partially transparent, and the transparency may be substantially similar to the transparency of the substrate 12. The additional layers may be conductive, and in some embodiments may be formed of a Transparent Conductive Oxide (TCO). In some embodiments, the additional layer may be a dielectric layer. In some embodiments, the additional layers may include multiple layers as part of a multilayer stack structure. The multilayer stack structure may include one or more layers of TCO material, dielectric material, insulator material, metal material, or semiconductor material. The selection of materials included in the additional layers may be influenced by the refractive index, thickness, or sequencing of the layers to achieve a desired reflectivity, transmittance, and/or color in the ablated region, the non-ablated region, or both. In the description below, the additional layer may be referred to as a conductive layer, but it should be understood that other additional layer materials described herein may be employed in place of the conductive layer. The coating 14 may be selectively ablated from the TCO or dielectric layer. The coating 14 may include one or more reflective layers comprising one or more metallic materials, metal oxides, metal nitrides, or other suitable materials that provide both reflectivity and opacity. In one embodiment, the workpiece 10 includes a glass substrate, an Indium Tin Oxide (ITO) layer on the glass substrate, and a coating including successive and adjacent layers of chromium (Cr), ruthenium (Ru), Cr, and Ru to form a glass/ITO/Cr/Ru/Cr/Ru material stack.

Some devices that may employ at least a portion of a laser ablated workpiece (e.g., electrochromic devices) may require one or more conductive layers, such as an electrode layer. For example, in an electrochromic device, electrodes may be included on opposite sides of the electrochromic medium whenever it is desired to activate the electrochromic medium in the device. Thus, the apparatus may also include an electrically conductive layer along at least a portion of the workpiece 10, the portion corresponding to the first ablated portion 24 of the workpiece 10. The conductive layer may be formed of TCO or other suitable conductive material such as ITO. In one embodiment, the conductive layer covers the entire workpiece 10.

As shown in fig. 1 and 2, the workpiece 10 in the illustrated process includes a conductive layer, shown as conductive layer 40, located at the second side 16 of the workpiece between the substrate 12 and the coating 14. The conductive layer 40 provides the second surface 20 from which the coating 14 is removed in this example. The illustrated process represents an example of a first laser ablation process in which a laser beam 100 propagates through a conductive layer 40, such as a metal layer, TCO layer, and ITO layer, to remove the coating 14 from the opposite side of the conductive layer 40. In other embodiments, the conductive layer 40 may be disposed on the second side 16 of the workpiece 10 after the ablation process.

As shown in fig. 2, the coating 14 may be a single layer or may be a multi-layer structure. The function of each layer in the multi-layer structure may be selected to perform a different physical, chemical, or optical function. For example, referring to fig. 2, the coating 14 may be subdivided into a plurality of sub-layers. In some embodiments, sub-layer 14A adjacent to conductive layer 40 may be an adhesion promoting layer, such as a layer comprising Cr or Ti. The second sublayer 14B may be a reflective layer. The reflective layer may include silver-gold-alloy chromium, ruthenium, stainless steel, silicon, titanium, nickel, molybdenum, chromium-molybdenum-nickel alloy, nickel-chromium, nickel-base alloy, nickel-indium (Inconel), indium, palladium, osmium, cobalt, cadmium, niobium, brass, bronze, tungsten, rhenium, iridium, aluminum alloy, scandium, yttrium, zirconium, vanadium, manganese, iron, zinc, tin, lead, bismuth, antimony, rhodium, tantalum, copper, gold, platinum, any other platinum group metal, alloys having a composition predominantly of the foregoing materials, and combinations thereof. The third sub-layer 14C may be an opaque layer. The opaque layer may include nickel silicide, chromium, nickel, titanium, Monel (Monel), cobalt, platinum, indium, vanadium, stainless steel, aluminum titanium alloy, niobium, ruthenium, molybdenum tantalum alloy, aluminum silicon alloy, nickel chromium molybdenum alloy, molybdenum rhenium alloy, molybdenum, tungsten, tantalum, rhenium, alloys consisting essentially of the foregoing, and combinations thereof. The opaque layer may comprise a material having a relatively large actual and hypothetical refractive index, such as an oxide, nitride, or the like. The fourth sub-layer 14D may be an electrically stable layer. The electrical stabilization layer may include platinum group metals such as iridium, osmium, palladium, platinum, rhodium, ruthenium, and alloys or mixtures thereof. In addition, the coating 14 may be further subdivided such that any sub-layer may include additional sub-layers within itself to meet the requirements of the stack.

According to the exemplary embodiment shown in fig. 4 and 5, a second laser ablation process is performed on workpiece 10 after coating 14 is removed from conductive layer 40 by the first laser ablation process. As shown in fig. 4 and 5, the laser spot 104 of the laser beam 100 is applied to a desired portion of the first ablated region 24 of the conductive layer 40 during the second laser ablation process, which is shown as second ablated region 32. As shown in fig. 5, the second ablation area 32 overlaps a desired portion of the first ablation area 24 such that the entirety of the second ablation area 32 is disposed within the first ablation area 24 that has been fully ablated (e.g., the second ablation area 32 does not span the first ablation area 24 and previously unablated areas, etc.). Thus, the second ablated region 32 is a sub-portion of the first ablated region 24 that is entirely contained within the first ablated region 24, wherein the workpiece 10 has been subjected to a first laser ablation pass to remove the coating 14 therefrom, thereby forming the first laser ablated region 24, and then the workpiece 10 is subjected to one or more additional laser ablation passes that do not remove any coating 14, but that completely overlap the desired portion of the first ablated region 24, forming the second ablated region 32 within the first ablated region 24 (i.e., the second ablated region 32 is entirely subjected to the first laser ablation pass and the one or more additional laser ablation passes).

This application of the laser spot 104 to the second ablation area 32 after the first ablation process is applied to the second ablation area may modify the surface of the conductive layer 40 that is subjected to the second laser ablation process within the second ablation area 32. For example, modification of the surface of conductive layer 40 may include reducing the thickness, roughening the surface, increasing the resistance, and/or changing the color of conductive layer 40 within second ablation area 32 relative to conductive layer 40 within first ablation area 24. According to one exemplary embodiment, the modifying includes thinning the conductive layer by a process of approximately zero to seven nanometers. In some embodiments, the conductive layer is thinned beyond seven nanometers (e.g., ten, fifteen, twenty nanometers, etc.).

According to an exemplary embodiment, such modification of conductive layer 40 within second ablated region 32 can induce a change in the optical properties of conductive layer 40 (e.g., reflection/absorption versus wavelength, etc.) in second ablated region 32, which results in a selectively visible mark shown as mark 200. The indicia 200 may include symbols, logos, images, patterns, words, phrases, warnings, identification numbers (e.g., product numbers, VIN numbers, serial numbers, bar codes, etc.), and/or the like. For example, the marker 200 may be generally invisible during normal operation, but may become visible during a darkened state, as described in more detail herein. As another example, a greater change in the thickness and/or roughness of the conductive layer 40 in the second ablated region 32 relative to the first ablated region 24 can provide an increasingly visible mark 200 in the darkened state. As yet another example, the modification to the second ablated region 32 can change its color from a first color (e.g., magenta, violet, a combination of red and blue, etc.; the color of the first ablated region 24, etc.) to a second, different color.

According to the exemplary embodiments shown in fig. 6-11, the device (shown as electrochromic device 300) comprises either a first electrochromic device (shown as window electrochromic device 302) or a second electrochromic device (shown as mirror electrochromic device 304). According to an exemplary embodiment, window electrochromic device 302 is configured as an aircraft window. In other embodiments, window electrochromic device 302 is configured as another type of window (e.g., an automobile window, a building window, etc.). According to an exemplary embodiment, the mirror electrochromic device 304 is configured as an automotive mirror (e.g., a rear view mirror, a side view mirror, etc.). In other embodiments, the mirror electrochromic device 304 is configured as another type of mirror (e.g., a bathroom mirror, etc.).

As shown in fig. 8 and 11, electrochromic device 300 includes a first substrate (e.g., similar to workpiece 10, etc., shown as first substrate 310), a second substrate (shown as second substrate 320), a sealing member (shown as seal 330), and a medium (shown as electrochromic medium 334). According to an exemplary embodiment, the first substrate 310 is at least partially transparent (e.g., substantially transparent, etc.). As shown in fig. 8 and 11, the first substrate 310 has a first surface (shown as an outer surface 312) and an opposing second surface (shown as an inner surface 314).

In some embodiments, the first substrate 310 is fabricated from any of a number of materials that are transparent or substantially transparent in the visible region of the electromagnetic spectrum. For example, the first substrate 310 may be or include: borosilicate glass; boroaluminosilicate glass; soda-lime glass; natural and synthetic polymer resins; plastic; and/or a composite material comprising: polyesters (e.g., PET), Polyimides (PI), polycarbonates, polysulfones, polyethylene naphthalatesEsters (PEN), ethylene-vinyl acetate copolymers (EVA), acrylate polymers, polyamides such as those available from Evonik Industries

CX 7323, cycloolefin polymers (COP) and cycloolefin copolymers (COC) such as

In some embodiments, the first substrate 310 is made of a glass sheet having a thickness in a range of about 0.10 millimeters (mm) to about 12.7mm, about 0.50mm to about 1.50mm, or about 0.65mm to about 1.00 mm. Of course, the thickness of the first substrate 310 may depend primarily on the particular application of the electrochromic device 300 (e.g., automotive application, aircraft application, etc.). Although a particular substrate material is disclosed for illustrative purposes only, many other substrate materials may be used, provided that they are substantially transparent and exhibit suitable physical properties (such as strength) so as to be capable of effective operation under the conditions of the intended use. Indeed, during normal operation, the electrochromic device 300 may be exposed to extreme temperature changes and large amounts of UV radiation primarily emitted by the sun. It will be further appreciated that the first substrate 310 may include a UV absorbing layer and/or contain UV absorbing materials to help protect the substrate and/or electrochromic medium 334 from UV damage.

As shown in fig. 8 and 11, the inner surface 314 of the first substrate 310 includes a first conductive layer disposed thereon, shown as a transparent conductive layer 316. According to an exemplary embodiment, the transparent conductive layer 316 serves as a first electrode of the electrochromic device 300. The transparent conductive layer 316 may include one or more layers of conductive material. One or more layers of the transparent conductive layer 316 may include materials such as: (i) substantially transparent in the visible region of the electromagnetic spectrum; (ii) bonds reasonably well to the first substrate 310; (iii) the bond is maintained when associated with the seal 330; (iv) generally resistant to corrosion from the electrochromic device 300 or materials contained within the atmosphere; and/or (v) exhibit minimal diffuse or specular reflection and sufficient electrical conductance. The conductive material of the transparent conductive layer 316 may be or include: fluorine doped tin oxide (FTO), such as TEC glass; indium/tin oxide (ITO); doping zinc oxide; indium zinc oxide; metal oxide/metal oxide (wherein the metal oxide may be replaced with metal carbide, metal nitride, metal sulfide, etc.); or other materials known to those of ordinary skill in the art. Alternatively, one or more metals or alloys may be deposited in a pattern that produces a grid or nanostructured electrode on the first substrate 310.

According to an exemplary embodiment, second substrate 320 of window electrochromic device 302 is at least partially transparent (e.g., substantially transparent, etc.). According to another exemplary embodiment, the second substrate 320 of the mirror electrochromic device 304 is opaque. As shown in fig. 8 and 11, the second substrate 320 has a third surface (shown as inner surface 322) and an opposing fourth surface (shown as outer surface 324). In some embodiments, the second substrate 320 is made of a similar material as the first substrate 310. In other embodiments, the second substrate 320 is made of a different material than the first substrate 310. In some embodiments, the second substrate 320 is made of a glass or plastic sheet having a thickness in the range of about 0.10mm to about 12.7mm, about 0.50mm to about 1.50mm, or about 0.65mm to about 1.00 mm. If the first substrate 310 and the second substrate 320 are made of glass sheets, the glass may optionally be tempered, heat strengthened, chemically strengthened, and/or laminated before or after being coated with a layer of conductive material.

As shown in fig. 8, the inner surface 322 of the second substrate 320 of the window electrochromic device 302 includes a second conductive layer disposed thereon, shown as a transparent conductive layer 326. According to an exemplary embodiment, transparent conductive layer 326 serves as a second electrode of window electrochromic device 302. Transparent conductive layer 326 may include one or more layers of conductive material. One or more layers of transparent conductive layer 326 may include materials such as: (i) substantially transparent in the visible region of the electromagnetic spectrum; (ii) bonds reasonably well to the second substrate 320; (iii) the bond is maintained when associated with the seal 330; (iv) generally resistant to corrosion from the window electrochromic device 302 or materials contained within the atmosphere; and/or (v) exhibit minimal diffuse or specular reflection and sufficient electrical conductance. The conductive material of the transparent conductive layer 326 may be or include: FTO, e.g., TEC glass; ITO; doping zinc oxide; indium zinc oxide; metal oxide/metal oxide (wherein the metal oxide may be replaced with metal carbide, metal nitride, metal sulfide, etc.); or other materials known to those of ordinary skill in the art. Alternatively, one or more metals or alloys may be deposited in a pattern that produces a grid or nanostructured electrode on the second substrate 320.

As shown in fig. 11, the inner surface 322 of the second substrate 320 of the mirror electrochromic device 304 includes a third conductive layer disposed thereon, shown as a reflective conductive layer 328. According to an exemplary embodiment, the reflective conductive layer 328 serves as the second electrode of the mirror electrochromic device 304. The reflective conductive layer 328 may include one or more layers of conductive material. One or more layers of the reflective conductive layer 328 may be of a material that: (i) substantially reflecting visible light; (ii) bonds reasonably well to the second substrate 320; (iii) the bond is maintained when associated with the seal 330; (iv) generally resistant to corrosion from the mirror electrochromic device 304 or materials contained within the atmosphere; and/or (v) exhibit sufficient conductance. The conductive material of the reflective conductive layer 328 may be or may include a reflective metal coating.

As shown in fig. 8 and 11, the second substrate 320 is spaced apart from the first substrate 310 such that an interior chamber, shown as chamber 332, is defined therebetween. As shown in fig. 8, electrochromic medium 334 is disposed within chamber 332 between transparent conductive layer 316 disposed on inner surface 314 of first substrate 310 and transparent conductive layer 326 disposed on inner surface 322 of second substrate 320 of window electrochromic device 302. As shown in fig. 11, the electrochromic medium 334 is disposed within the chamber 332 between the transparent conductive layer 316 disposed on the inner surface 314 of the first substrate 310 and the reflective conductive layer 328 disposed on the inner surface 322 of the second substrate 320 of the mirror electrochromic device 304.

According to an exemplary embodiment, the seal 330 is positioned to effectively seal the chamber 332 such that the electrochromic medium 334 does not leak therefrom. The seal 330 may extend between and around the entire perimeter of the interior surface 314 of the first substrate 310 and the interior surface 322 of the second substrate 320. The seal 330 may be or may comprise any material that is capable of adhesively bonding to conductive materials coated on the first substrate 310 (e.g., transparent conductive layer 316, etc.) and the second substrate 320 (e.g., transparent conductive layer 326, reflective conductive layer 328, etc.) to seal the electrochromic medium 334 within the chamber 332. For example, the seal 330 may (i) have good adhesion to glass, metals, metal oxides, and/or other substrate materials, (ii) have low permeability to oxygen, moisture vapor, and/or other adverse vapors and gases, and (iii) not interact with or poison the electrochromic medium 334 that the seal 330 is intended to contain and protect. In some embodiments, a portion of the conductive layer (e.g., transparent conductive layer 316, transparent conductive layer 326, reflective conductive layer 328, etc.) may be partially removed with the seal 330 positioned therein. In such embodiments, the seal 330 may be configured to bond and adhere to glass, plastic, or other substrates that are not electrically conductive.

According to an exemplary embodiment, the composition of electrochromic medium 334 disposed within chamber 332 may include at least one anodic electroactive material, at least one cathodic electroactive material, and at least one solvent. At least one of the anodic electroactive material and the cathodic electroactive material may be electrochromic. Typically, both the anode material and the cathode material are electroactive materials, and at least one of them is an electrochromic material. It is to be understood that, regardless of its ordinary meaning, the term "electroactive" will be defined herein as a material that changes its oxidation state when exposed to a particular potential difference. Further, it is to be understood that, regardless of its ordinary meaning, the term "electrochromic" will be defined herein as a material that changes its extinction coefficient at one or more wavelengths when exposed to a particular potential difference.

Electrochromic medium 334 may comprise a single layer of material that may include small non-uniform regions and include a solution phase arrangement in which the material may be contained in a solution of an ion conducting electrolyte in which it remains when electrochemically oxidized or reduced. The solution phase electroactive material may be included in a continuous solution phase of the gel composition. More than one anode and cathode material may be combined to achieve a preselected color. The anode material and the cathode material may also be combined or linked by a bridging unit. Additionally, a single layer, single phase composition can comprise a composition wherein the anode material and the cathode material are incorporated into a polymer matrix. Electrochromic medium 334 may be composed of layers and/or may include materials directly attached to or confined in close proximity to a conductive electrode (e.g., transparent conductive layer 316, transparent conductive layer 326, reflective conductive layer 328, etc.) that, when electrochemically oxidized or reduced, remain attached or confined. In the electrochromic medium 334, one or more materials may undergo a phase change during operation of the electrochromic device 300. For example, when electrochemically oxidized or reduced, materials contained in solution in an ion conducting electrolyte form a layer on a conductive electrode.

In addition, electrochromic medium 334 may include other materials such as UV absorbers, UV stabilizers, heat stabilizers, antioxidants, thickeners, viscosity modifiers, colorants, redox buffers, and mixtures thereof. Suitable UV stabilizers may include, but are not limited to, 2-ethyl-2-cyano-3, 3-diphenyl acrylate; acrylic acid (2-ethylhexyl) -2-cyano-3, 3-diphenyl ester; 2- (2 '-hydroxy-4' -methylphenyl) benzotriazole, sold under the trademark Tinuvin P by Ciba-Geigy Corp; pentyl 3- [3- (2H-benzotriazol-2-yl) -5- (1, 1-dimethylethyl) -4-hydroxyphenyl ] propionate, prepared by Tinuvin 213, sold by Ciba-Geigy, Inc., by conventional hydrolysis followed by conventional esterification (hereinafter referred to as "Tinuvin PE"); 2, 4-dihydroxybenzophenone; 2-hydroxy-4-methoxybenzophenone; and 2-ethyl-2' -ethoxyalaninamide. In some embodiments, the electrochromic composition further comprises an anodic and/or cathodic color stabilizing redox buffer. In some embodiments, electrochromic medium 334 may additionally comprise a cross-linked polymer matrix, a stand-alone gel, and/or a substantially non-exuding gel.

The anode material may comprise any of a number of materials including: ferrocene, substituted ferrocenium salts, phenazines, substituted phenazines, phenothiazines, substituted phenothiazines (including substituted triphenodithiazines), thienes, and substituted thienes. Examples of the anode material may include di-tert-butyl-diethylferrocene; 5, 10-dimethyl-5, 10-Dihydrophenazine (DMP); 3,7, 10-trimethylphenothiazine; 2,3,7, 8-tetramethoxy-kadethiene; 10-methylphenothiazine; tetramethylphenazine (TMP); and bis (butyltriethylammonium) -p-methoxytriphenodithiazine (TPDT). The anode material may also include thin films of polymers such as polyaniline, polythiophene, polymeric metallocenes, or solid transition metal oxides including, but not limited to, oxides of vanadium, nickel, and iridium, as well as a number of heterocyclic compounds.

In another embodiment, at least one of the anode electroactive materials comprises a phenazine compound, which compound may be substituted or unsubstituted, illustrative phenazine compounds include, but are not limited to, 2, 7-dialkyl-5, 10-dihydrophenazine, in some such embodiments, at least one alkyl group of a 5, 10-dialkyl group in the phenazine has at least 4 carbon atoms and does not contain any β -hydrogen atoms, and at least one alkyl group of a 2, 7-dialkyl group in the phenazine has at least 4 carbon atoms.

The cathode material may include, for example, viologens such as methyl viologen tetrafluoroborate, octyl viologen tetrafluoroborate (octyl viologen), or benzyl viologen tetrafluoroborate; and/or ferrocenium salts, such as (6- (tri-t-butylferrocenium) hexyl) triethylammonium di-tetrafluoroborate (TTBFc).⁺). Although specific cathode materials are provided for illustrative purposes only, many other conventional cathode materials may be used. The cathode material may include a thin film of a polymer (e.g., various polythiophenes or polymers)Viologen), inorganic thin films, or solid transition metal oxides, including but not limited to tungsten oxide in one embodiment, the at least one cathodic electroactive material includes viologen in another embodiment, the at least one cathodic electroactive material includes a 1,1 '-dialkyl-4, 4' -bipyridine compound in another embodiment, the at least one alkyl group attached to the bipyridine compound includes at least 4 carbon atoms, and less than two β -hydrogen atoms in another embodiment, the at least one alkyl group of the bipyridinium compound includes a (2-ethylhexyl) group₄ ^-、PF₆ ^-、SbF₆ ^-P-toluenesulfonate, trifluoromethanesulfonate or bis-trifluoromethanesulfonylimide.

As shown in fig. 8 and 11, the transparent conductive layer 316 of the first substrate 310 includes the mark 200. For example, the transparent conductive layer 316 of the first substrate 310 may undergo (i) a first laser ablation process (see fig. 1-3) such that the transparent conductive layer 316 has a first ablation area 24; and (ii) a second laser ablation process (see fig. 4-5) such that the transparent conductive layer 316 has a second ablated region 32 that overlaps a portion of the first ablated region 24, thereby defining the mark 200 in and/or on the transparent conductive layer 316.

As shown in fig. 6, 8, 9, and 11, the electrochromic device 300 is configured to be in a first state (e.g., a transparent state, a clear state, an uncolored state, a non-darkened state, etc.) that is displayed as the transparent state 306 such that its indicia 200 is at least partially invisible (e.g., sufficiently invisible, obscured, transparent, unobtrusive, etc.). As shown in fig. 7 and 10, the electrochromic device 300 is configured to be in a second state (e.g., a colored state, a darkened state, a dimmed state, etc.) that is displayed as a darkened state 308 such that its indicia 200 is visible (e.g., sufficiently visible, noticeable, perceptible, etc.). According to an exemplary embodiment, the electrochromic medium 334 disposed within the chamber 332, the transparent conductive layer 316 of the first substrate 310, and (i) the transparent conductive layer 326 or (ii) the reflective conductive layer 328 of the second substrate 320 facilitate selective display of the indicia 200. For example, a user of the electrochromic device 300 may selectively activate the dimmed state 308 of the electrochromic device 300 such that the electrochromic device 300 transitions from the transparent state 306 to the dimmed state 308 (e.g., by pressing a dim button, a color button, etc. associated with the electrochromic device 300). The indicia 200 of the window electrochromic device 302 and the mirror electrochromic device 304 produced by the first laser ablation process and the second laser ablation process may therefore be invisible when the electrochromic medium 334 is in the transparent state 306 and visible when the electrochromic medium 334 is in the darkened state 308.

Results of the experiment

Various experiments were conducted to modify different sample substrates (e.g., substrates such as workpiece 10, first substrate 310, second substrate 320, etc.) using laser ablation processes with varying laser ablation settings and/or parameters. As described in more detail herein, experiments demonstrate that various properties of the conductive layers (e.g., conductive layer 40, transparent conductive layer 316, transparent conductive layer 326, reflective conductive layer 328, etc.) can be changed using a laser ablation method that includes the first and second laser ablation processes described above. More specifically, the thickness, color, resistance, and/or still other characteristics of the conductive layer may be selectively modified using this laser ablation method.

Various samples of the substrate were subjected to the laser ablation method described above, as shown in tables 1-4 below. Specifically, various test substrates were subjected to a first laser ablation process and a second laser ablation process, while various control substrates were subjected to only the first laser ablation process. In addition, the number of passes is selectively varied during the second laser ablation process.

Referring to fig. 12, a graph 500 is shown including different thickness data points 502 according to the number of laser ablation passes, according to an exemplary embodiment. The different thickness data points 502 correspond to differences in the thickness data in table 1, and depict differences between the relevant control substrate thickness data and the test substrate thickness data. The control substrate thickness data indicates a thickness (in nanometers) of a conductive layer on the control substrate after undergoing a first laser ablation process (e.g., to remove a coating, etc.). The test substrate thickness data indicates the thickness (in nanometers) of the conductive layer on the test substrate after undergoing the first and second laser ablation processes (e.g., to remove the coating, then modify the conductive layer, etc.). As shown in table 1 and fig. 12, the thickness of the conductive layer decreased as the corresponding substrate was exposed to additional laser passes. For example, the thickness of the conductive layer on the test substrate after a single laser pass (e.g., a first laser ablation process, etc.) is the same relative to the control substrate, while the thickness of the conductive layer on the test substrate is reduced after subjecting the conductive layer to an additional laser pass (e.g., a second laser ablation process, etc.). Specifically, as shown in table 1 and fig. 12, each subsequent laser pass reduces the thickness of the conductive layer of the test substrate from having the same thickness after a single pass to seven nanometers less after ten or more laser pulses according to a non-linear trend (e.g., similar to a function) relative to the conductive layer of the control substrate. In some embodiments, the thickness of the conductive layer decreases according to another type of trend (e.g., based on selected parameters of the laser ablation process, etc.). In some embodiments, the thickness of the conductive layer of the test substrate is reduced by more than seven nanometers (e.g., ten, fifteen, twenty nanometers, etc.) during the second laser ablation process.

Table 1: thickness data

Referring to fig. 13, a graph 600 including resistance data points 602 according to the number of laser ablation passes is shown, according to an example embodiment. The resistance data points 602 correspond to the difference in resistance data in table 2 and depict the change in resistance (in ohms/square) of the conductive layer on the test substrate after undergoing the first laser ablation process and the second laser ablation process relative to the resistance of the conductive layer on the control substrate after undergoing only the first laser ablation process. As shown in table 1 and fig. 13, the resistance of the conductive layer increases after each subsequent laser pass according to a substantially linear trend (e.g., similar to a function, etc.). In some embodiments, the resistance of the conductive layer increases according to another type of trend (e.g., a non-linear trend, based on selected parameters of the laser ablation process, etc.).

Table 2: resistance data

Referring now to fig. 14, graph 700 includes a data points 702 and b data points 704 according to the number of laser ablation passes. a data points 702 and b data points 704 correspond to the data in table 3 and depict color changes in a space and b space seen and measured from the uncoated surface of the test substrate (e.g., first side 18, outer surface 312, outer surface 324, etc.) after undergoing the first and second laser ablation processes relative to seen and measured from the uncoated surface of the control substrate after undergoing only the first laser ablation process. Referring now to fig. 15, graph 800 includes a data points 802 and b data points 804 according to the number of laser ablation passes. a data points 802 and b data points 804 correspond to the data in table 4 and depict the color change in a space and b space seen and measured from the coated surface of the test substrate (e.g., second side 16, inner surface 314, inner surface 322, etc.) after undergoing the first and second laser ablation processes relative to the color change seen and measured from the coated surface of the control substrate after undergoing only the first laser ablation process.

Table 3: uncoated surface data

Table 4: coating surface data

According to an exemplary embodiment, colors may be mapped onto a three-dimensional integer space referred to as a laboratory color space. The laboratory color space is defined by a, b and L spaces. L space represents brightness, a space represents the red/green opponent color, and b space represents the yellow/blue opponent color. For example, L in L space indicates the luminance between the darkest black and the whitest white, negative a indicates green, positive a indicates red, negative b indicates blue, and positive b indicates yellow. As shown in fig. 14 and 15, subjecting the test substrate to additional laser passes causes the color of the coating to increase (e.g., more positive, etc.) in b-space (e.g., more yellow, etc.) and decrease (e.g., more negative, etc.) in a-space (e.g., more green, etc.).

By measuring the color of the conductive layer in the laboratory space of both the test substrate and the control substrate, the color difference therebetween can be quantified as shown in equation (1):

wherein, Delta E^*Is the color difference, Δ a^*Is the difference between a-values of the test and control substrates, Δ b^*Is the difference between b values of the test substrate and the control substrate, and Δ L^*Is the difference between the L values of the test and control substrates.

Referring now to fig. 16, graph 900 includes a first or uncoated side color variation curve 902 and a second or coated side color variation curve 904. As shown in tables 3 and 4 and fig. 16, the greater the color change of the test substrate as the coating of the test substrate was subjected to additional laser passes during the second laser ablation process. Specifically, the color variation may range from 0 to 3.5 or higher. As one example, it may be desirable to have a faint mark 200 or "just a significant difference" ("JND") such that the number of laser passes of the second laser ablation process is selected such that the color variation is in a range between 0 and 1.0 (e.g., 0.13, 0.4, 0.6, etc.). As another example, it may be desirable to make the mark 200 more visible and noticeable such that the number of laser passes of the second laser ablation process is selected such that the color change is greater than 1.0 (e.g., 1.5, 2.3, 2.8, 3.1, 3.3, etc.).

As represented in fig. 12, 13, and 16, the thickness, resistance, and/or color of the conductive layer of the substrate may thus be selectively altered or modified as desired by controlling the number of laser passes (and laser characteristics, such as speed, pitch, intensity, diameter, etc.) that the substrate undergoes during the second laser ablation process.

It is to be understood that the foregoing description is of one or more preferred exemplary embodiments of the invention. The present invention is not limited to the specific embodiments disclosed herein, but is defined only by the appended claims. Furthermore, statements contained in the foregoing description relate to particular embodiments and are not to be construed as limitations on the scope of the invention or on the definition of terms used in the claims, except where a term or phrase is expressly defined above. Various other embodiments and various changes and modifications to the disclosed embodiments will become apparent to those skilled in the art. All such other embodiments, variations and modifications are intended to fall within the scope of the appended claims.

As used in this specification and claims, the terms "for example/for instance" and "like" and the verbs "comprising," "having," "including," and their other verb forms, when used in conjunction with a listing of one or more components or other items, are each to be construed as open-ended, meaning that the listing is not to be considered as excluding other, additional components or items. Other terms are to be understood using their broadest reasonable meaning unless they are used in a context that requires a different interpretation.

Claims

1. A product, comprising:

a first substrate at least partially transparent to visible light, the first substrate comprising:

a first surface;

an opposing second surface; and

a first conductive layer disposed on the opposing second surface, the first conductive layer having a first ablated area and a second ablated area disposed entirely within and overlapping a portion of the first ablated area, wherein the second ablated area defines a selectively visible indicia.

2. The product of claim 1, wherein the first ablated region is formed by subjecting the first conductive layer to a first laser ablation process, and wherein the second ablated region is formed by subjecting the first conductive layer to the first and second laser ablation processes.

3. The product of claim 1, further comprising a second substrate spaced apart from the first substrate, wherein the second substrate has a third surface and an opposing fourth surface, the third surface including a second conductive layer disposed thereon.

4. The product of claim 3, wherein the second conductive layer is a reflective conductive layer.

5. The product of claim 3, wherein the second conductive layer is a transparent conductive layer.

6. The product of claim 1, wherein the first ablated region of the first conductive layer has a first thickness and the second ablated region of the first conductive layer has a second thickness, wherein the second thickness is less than the first thickness.

7. The product of claim 1, wherein the first ablated region of the first conductive layer has a first resistance and the second ablated region of the first conductive layer has a second resistance, wherein the second resistance is greater than the first resistance.

8. The product of claim 1, wherein the first ablated regions of the first conductive layer have a first color and the second ablated regions of the first conductive layer have a second color, wherein the second color is different from the first color.

9. An electrochromic device, comprising:

a first substrate having a first surface and an opposing second surface, the opposing second surface including a first conductive layer disposed thereon, the first conductive layer having a first ablation area and a second ablation area disposed entirely within and overlapping a portion of the first ablation area, wherein the first ablation area is formed by subjecting the first conductive layer to a first laser ablation process, and wherein the second ablation area is formed by additionally subjecting the portion of the first ablation area to a second laser ablation process;

a second substrate spaced apart from the first substrate to define an interior chamber therebetween, the second substrate having a third surface and an opposing fourth surface, the third surface including a second conductive layer disposed thereon; and

an electrochromic medium disposed within the internal chamber between the first and second electrically conductive layers, wherein the second ablated region is at least partially invisible when the electrochromic medium is in a transparent state, and wherein the second ablated region is visible when the electrochromic medium is in a darkened state.

10. The electrochromic device of claim 9, wherein the first conductive layer is a transparent conductive layer.

11. The electrochromic device of claim 9, wherein the second conductive layer is a transparent conductive layer or a reflective conductive layer.

12. The electrochromic device of claim 9, wherein the second ablated region comprises selectively visible indicia.

13. The electrochromic device of claim 9, wherein the first ablated region of the first conductive layer has a first thickness and the second ablated region of the first conductive layer has a second thickness, wherein the second thickness is less than the first thickness.

14. The electrochromic device of claim 9, wherein the first ablated region of the first conductive layer has a first resistance and the second ablated region of the first conductive layer has a second resistance, wherein the second resistance is greater than the first resistance.

15. The electrochromic device of claim 9, wherein the first ablated region of the first conductive layer has a first color and the second ablated region of the first conductive layer has a second color, wherein the second color is different from the first color.

16. A method, comprising:

providing a substrate having a first side and an opposing second side, the opposing second side comprising a conductive layer and a coating disposed on the conductive layer;

subjecting the substrate to a first laser ablation pass such that the coating is removed from at least a portion of the conductive layer; and

subjecting the portion of the substrate to one or more additional laser ablation passes to alter a property of at least a sub-portion of the conductive layer, wherein a sub-portion is entirely contained within an area of the portion of the substrate that is subjected to the first laser ablation pass such that the one or more additional laser ablation passes do not remove any coating from the conductive layer.

17. The method of claim 16, wherein modifying properties of the sub-portions of the conductive layer induces a change in an optical characteristic of the conductive layer that produces a selectively visible mark within the substrate.

18. The method of claim 16, wherein the property of the conductive layer comprises a thickness, wherein the thickness of the sub-portion of the conductive layer is less than a remaining portion of the conductive layer.

19. The method of claim 16, wherein the property of the conductive layer comprises a resistance, wherein the sub-portion of the conductive layer has a greater resistance than a remaining portion of the conductive layer.

20. The method of claim 16, wherein the property of the conductive layer comprises a color, wherein the color of the sub-portion of the conductive layer is different from a remaining portion of the conductive layer.