Solar control coatings with quadruple metallic layers

Abstract

To provide a coated article with a desired visible light transmittance (LTA) and a desired solar heat gain coefficient (SHGC).SOLUTION: A coated article includes a substrate, a first dielectric layer, a first metallic layer, a first primer layer, a second dielectric layer, a second metallic layer, a second primer layer, a third dielectric layer, a third metallic layer, a third primer layer, a fourth dielectric layer, a fourth metallic layer, a fourth primer layer, a fifth dielectric layer, and an overcoat. At least the first metallic layer and / or the fourth metallic layer are discontinuous layers.SELECTED DRAWING: None

Description

Technical Field

[0001] (Cross - Reference to Related Applications) This application claims priority to U.S. Provisional Patent Application No. 62 / 626,332, filed on February 5, 2018, the entire disclosure of which is incorporated herein by reference. The present invention generally relates to a solar - control coating having four metal layers.

Background Art

[0002] Solar - control coatings are known in the fields of transparent materials for buildings and vehicles. These solar - control coatings block or filter selected ranges of electromagnetic radiation, for example, in the range of solar infrared radiation or solar ultraviolet radiation, in order to reduce the amount of solar energy entering a vehicle or a building. This reduction in solar energy transmittance helps to reduce the load on the cooling unit of the vehicle or building.

Summary of the Invention

[0003] The coating of the present invention includes a coating that covers at least a portion of a substrate. The coating includes at least three continuous metal layers and at least one discontinuous metal layer. The discontinuous metal layer can increase the visible - light absorption of the coating and, in combination with a dielectric layer of appropriate thickness, can provide an asymmetric reflectance to the coated article. The coating of the present invention includes a coating that covers at least a portion of a substrate. The coating includes at least four metal layers alternating with at least five dielectric layers, and at least one of the metal layers includes a discontinuous metal layer having a discontinuous metal region.

[0004] The coated article of the present invention includes a substrate and a coating formed on at least a part of the substrate. The coating includes a first dielectric layer formed on at least a part of the substrate, a first metal layer formed on at least a part of the first dielectric layer, a second dielectric layer formed on at least a part of the first metal layer, a second metal layer formed on at least a part of the second dielectric layer, a third dielectric layer formed on at least a part of the second metal layer, a third metal layer formed on at least a part of the third dielectric layer, a fourth dielectric layer formed on at least a part of the third metal layer, a fourth metal layer formed on at least a part of the fourth dielectric layer, a fifth dielectric layer formed on at least a part of the fourth metal layer, and an optional protective layer formed on at least a part of the third metal layer. At least one of the metal layers is a discontinuous layer. For example, the second metal layer or the third metal layer can be a discontinuous layer.

[0005] The additional coated article includes a substrate and a coating stack covering at least a portion of the substrate. The coating includes a first dielectric layer formed on at least a portion of the substrate. The first dielectric layer includes a first film and a second film covering the first film. A first metal layer is disposed on the first dielectric layer. Any first primer layer is disposed on the first metal layer. A second dielectric layer is disposed on any first primer layer or on the first metal layer. The second dielectric layer includes a first film and a second film covering the first film. Optionally, a third film is disposed on the second film. A second metal layer is disposed on the second dielectric layer. A third dielectric layer is disposed on the second metal layer. The third dielectric layer includes a first film and a second film covering the first film. Optionally, a third film of the third dielectric layer can be disposed on the second film. A third metal layer is disposed on the third dielectric layer. A fourth dielectric layer including a first film and a second film covering the first film is disposed on the third metal layer. Optionally, a third film of the fourth dielectric layer can be disposed on the second film. A fourth metal layer is disposed on the fourth dielectric layer. Any fourth primer layer is disposed on the fourth metal layer. A fifth dielectric layer including a first film and a second film disposed on the first film is disposed on the fourth metal layer. At least one of the metal layers is a discontinuous layer having discontinuous metal regions. For example, the second metal layer or the third metal layer is a discontinuous layer having discontinuous metal regions.

[0006] A method of making a coated article, including providing a substrate. A first dielectric layer is applied over at least a portion of the substrate. A first metal layer is applied over at least a portion of the first dielectric layer. An optional first primer layer is applied over at least a portion of the first metal layer. A second dielectric layer is applied over the optional first primer layer or at least a portion of the first metal layer. A second metal layer is applied over at least a portion of the second dielectric layer. A third dielectric layer is applied over the optional second primer layer or at least a portion of the second metal layer. A third metal layer is applied over at least a portion of the third dielectric layer. A fourth dielectric layer is applied over the optional third primer layer or at least a portion of the third metal layer. A fourth metal layer is applied over at least a portion of the fourth dielectric layer. A fifth dielectric layer is applied over the optional fourth primer layer or at least a portion of the fourth metal layer. At least one of the metal layers is a discontinuous layer having discontinuous metal regions. For example, the second metal layer or the third metal layer is a subcritical metallic layer having discontinuous metal regions. There may be no optional primer immediately above the discontinuous layer.

[0007] Another embodiment of the present invention is a transparent building material. The transparent material has a first ply having a first surface and a second surface, and a second ply having a third surface and a fourth surface. As described herein, the coating is disposed over at least a portion of the second surface or the third surface.

[0008] Another embodiment of the present invention is a method of making a transparent building material. The method includes providing a first ply having a first surface and a second surface, and a second ply having a third surface and a fourth surface. Either the second surface of the first ply or the third surface of the second ply has the coating described herein. The first ply and the second ply are assembled such that the second surface faces the third surface and there is a gap between the second surface and the third surface. The gap is filled with gas.

[0009] The present invention will be described with reference to the following drawings, and like reference numerals identify like parts throughout.

Brief Description of the Drawings

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Figure 7

Modes for Carrying Out the Invention

[0017] As used herein, spatial or directional terms such as "left", "right", "inner", "outer", "upper", "lower", etc. are related to the present invention as shown in the drawings. However, it should be understood that the present invention can assume various alternative orientations, and thus such terms should not be considered limiting. Further, as used herein, all numbers representing dimensions, physical properties, processing parameters, amounts of components, reaction conditions, etc. used in the specification and claims are to be understood as being modified in all cases by the term "about". Accordingly, unless indicated to the contrary, the numerical values set forth in the following specification and claims can vary depending on the desired properties sought to be obtained by the present invention. At a minimum, and not as an attempt to limit the application of the doctrine of equivalents to the claims, each numerical value should be construed at least by applying ordinary rounding techniques in light of the number of significant figures reported. Further, all ranges disclosed herein are to be understood to include the starting and ending values of the range, as well as every sub-range subsumed therein. For example, a recited range of "1 to 10" includes every sub-range between (and including) the minimum value of 1 and the maximum value of 10, i.e., every sub-range that begins with a minimum value of 1 or more and ends with a maximum value of 10 or less, such as, for example, 1 to 3.3, 4.7 to 7.5, 5.5 to 10, etc. Further, as used herein, the terms "formed on", "deposited on", or "provided on" mean formed, deposited, or provided on the surface, but not necessarily in contact with the surface. For example, a coating layer "formed on" a substrate does not exclude the presence of one or more other coating layers or films of the same or different composition located between the formed coating layer and the substrate. The term "visible region" or "visible light" refers to electromagnetic radiation having wavelengths in the range of 380 nm to 800 nm. The term "infrared region" or "infrared radiation" refers to electromagnetic radiation having wavelengths in the range of greater than 800 nm to 100,000 nm. The term "ultraviolet region" or "ultraviolet radiation" means electromagnetic energy having wavelengths in the range of 300 nm to less than 380 nm.Furthermore, without limitation, all documents referred to in this specification, such as issued patents and patent applications, should be considered to be "incorporated by reference" in their entirety. As used herein, the term "film" refers to the coated area of a desired or selected coating composition. A "layer" can include one or more "films", and a "coating" or "coating stack" can include one or more "layers". The term "asymmetric reflectance" means that the visible light reflectance of the coating from one side is different from the visible light reflectance of the coating from the opposite side. The term "critical thickness" means the thickness above which the coating material forms a continuous, unbroken layer and below which the coating material forms a discontinuous region or islands of the coating material rather than a continuous layer. The term "subcritical thickness" means a thickness less than the critical thickness such that the coating material forms isolated, non-connected regions of the coating material. The term "island-like" means that the coating material does not form a continuous layer, but rather the material is deposited to form isolated regions or islands.

[0018] For the purposes of the following description, the invention is described with respect to, without limitation, use with architectural transparent materials such as insulating glass units (IGUs). As used herein, the term "architectural transparent material" refers to, without limitation, any transparent material disposed in a building, such as windows and skylights. However, it should be understood that the invention is not limited to use with such architectural transparent materials and can be practiced with transparent materials in any desired field, such as, without limitation, laminated or non-laminated residential and / or commercial windows, insulating glass units, and / or transparent materials for land, air, space, water, and underwater vehicles. Thus, it should be understood that the specifically disclosed exemplary embodiments are presented merely to illustrate the general concepts of the invention and that the invention is not limited to these particular exemplary embodiments. Further, a typical "transparent material" can have a sufficient visible light transmittance such that materials can be seen through the transparent material, but in the practice of the invention, a "transparent material" need not be transparent to visible light and can be translucent or opaque.

[0019] A non-limiting transparent material 10 incorporating the features of the present invention is shown in FIG. 1. The transparent material 10 can have any desired transmittance and / or reflectance of visible light, infrared radiation, or ultraviolet radiation. For example, the transparent material 10 can have any desired amount of visible light transmittance, for example, greater than 0% and up to 100%.

[0020] The exemplary transparent material 10 of FIG. 1 is in the form of a conventional insulating glass unit and includes a first ply 12 having a first major surface 14 (surface 1) and an opposing second major surface 16 (surface 2). In the illustrated non-limiting embodiment, the first major surface 14 faces the exterior of the building, i.e., the outer major surface, and the second major surface 16 faces the interior of the building. The transparent material 10 also has an outer (first) major surface 20 (surface 3) and an inner (second) major surface 22 (surface 4) and includes a second ply 18 spaced from the first ply 12. This numbering of the ply surfaces is consistent with convention in fenestration technology. The first and second plies 12, 18 can be connected to each other in any suitable manner, such as by being adhesively bonded to a conventional spacer frame 24. A gap or chamber 26 is formed between the two plies 12, 18. The chamber 26 can be filled with a selected atmosphere such as air, or a non-reactive gas such as argon or krypton gas. A solar control coating 30 (or any of the other coatings described below) is formed on at least a portion of one of the plies 12, 18, for example, but not limited to, at least a portion of the second surface 16 or at least a portion of the third surface 20. Alternatively, if desired, the first surface or the fourth surface can also be coated. Examples of insulating glass units can be found, for example, in U.S. Patent Nos. 4,193,236, 4,464,874, 5,088,258, and 5,106,663.

[0021] In a broad implementation of the present invention, the plies 12, 18 of the transparent material 10 can be of the same or different materials. The plies 12, 18 can include any desired material having any desired properties. For example, one or more of the plies 12, 18 can be transparent or translucent to visible light. "Transparent" means having a visible light transmittance greater than 0% and up to 100%. Alternatively, one or more of the plies 12, 18 can be translucent. "Translucent" means allowing electromagnetic energy (e.g., visible light) to pass through, but diffusing this energy so that an object on the opposite side of the observer cannot be clearly seen. Examples of suitable materials include, but are not limited to, plastic substrates (e.g., acrylic polymers such as polyacrylate; polyalkyl methacrylates such as polymethyl methacrylate, polyethyl methacrylate, polypropyl methacrylate; polyurethane; polycarbonate; polyalkyl terephthalates such as polyethylene terephthalate (PET), polypropylene terephthalate, polybutylene terephthalate; polysiloxane-containing polymers; or copolymers of any monomers for preparing these, or any mixtures thereof), ceramic substrates, glass substrates, or any mixtures or combinations of the above. For example, one or more of the plies 12, 18 can include conventional soda-lime silicate glass, borosilicate glass, or leaded glass. The glass can be clear glass. "Clear glass" means glass that is not tinted or non-colored. Alternatively, the glass can be tinted or otherwise colored glass. The glass can be annealed glass or heat-treated glass. As used herein, the term "heat treatment" means annealing or at least partial annealing. The glass can be of any type, such as conventional float glass, and can have any composition with any optical properties, e.g., any value of visible transmittance, ultraviolet transmittance, infrared transmittance, and / or total solar energy transmittance."Float glass" means glass formed by a conventional float process in which molten glass is deposited on a molten metal bath and controllably cooled to form a float glass ribbon. Examples of the float glass process are disclosed in U.S. Patent No. 4,466,562 and U.S. Patent No. 4,671,155.

[0022] The first and second plies 12, 18 can each be, for example, clear float glass, tinted, or colored glass, or one of the plies 12, 18 can be clear glass and the other ply 12, 18 can be colored glass. Without limiting the invention, examples of glass suitable for the first ply 12 and / or the second ply 18 are described in U.S. Patent No. 4,746,347, U.S. Patent No. 4,792,536, U.S. Patent No. 5,030,593, U.S. Patent No. 5,030,594, U.S. Patent No. 5,240,886, U.S. Patent No. 5,385,872, and U.S. Patent No. 5,393,593. The first and second plies 12, 18 can have any desired dimensions, such as length, width, shape, or thickness. In one exemplary automotive transparent material, the first and second plies can each have a thickness of from 1 mm to 10 mm, such as from 1 mm to 8 mm, such as from 2 mm to 8 mm, such as from 3 mm to 7 mm, such as from 5 mm to 7 mm, such as 6 mm.

[0023] The solar control coating 30 of the present invention is deposited on at least a part of at least one major surface of one of the glass plies 12, 18. In the example shown in FIG. 1, the coating 30 is formed on at least a part of the inner surface 16 of the outer glass ply 12. As used herein, the term "solar control coating" refers to a coating composed of one or more layers or films that affect the solar characteristics of the coated article, such as, but not limited to, the amount of solar radiation, e.g., visible light radiation, infrared radiation or ultraviolet radiation, reflected from, absorbed by, or transmitted through the coated article; shading coefficient; emissivity, etc. The solar control coating 30 can block, absorb or filter a selected portion of the solar spectrum, such as, but not limited to, the IR, UV and / or visible spectra.

[0024] The solar control coating 30 can be deposited by any conventional method, such as, but not limited to, conventional chemical vapor deposition (CVD) methods and / or physical vapor deposition (PVD) methods. Examples of CVD processes include spray pyrolysis. Examples of PVD processes include electron beam evaporation and vacuum sputtering (such as magnetron sputter vapor deposition (MSVD)). Other coating methods, such as, but not limited to, sol-gel deposition, can also be used. In one non-limiting embodiment, the coating 30 can be deposited by MSVD. Examples of MSVD coating apparatuses and methods are well understood by those skilled in the art and are described, for example, in U.S. Patent Nos. 4,379,040, 4,861,669, 4,898,789, 4,898,790, 4,900,633, 4,920,006, 4,938,857, 5,328,768 and 5,492,750.

[0025] An exemplary non-limiting sunlight control coating 30 of the present invention is shown in FIG. 4. This exemplary coating 30 includes a base layer or a first dielectric layer 440 deposited on at least a portion of the major surface of a substrate (e.g., the second surface 416 of the first ply 12). The first dielectric layer 440 can be a single layer or, without limitation, can include a plurality of films of anti-reflective materials and / or dielectric materials such as metal oxides, metal alloy oxides, nitrides, oxynitrides, or mixtures thereof. The first dielectric layer 440 can be transparent to visible light. Examples of suitable metal oxides or metal nitrides for the first dielectric layer 440 or any film therein include oxides, nitrides, or oxynitrides of titanium, hafnium, zirconium, niobium, zinc, bismuth, lead, indium, tin, aluminum, silicon, and mixtures thereof. The metal oxide can have small amounts of other materials, such as manganese in bismuth oxide, tin in indium oxide, etc. Further, oxides of metal alloys or metal mixtures, such as oxides containing zinc and tin (e.g., zinc stannate as defined below), indium-tin alloys, silicon nitride, silicon aluminum nitride, or oxides of aluminum nitride can be used. Further, doped metal oxides, such as tin oxide doped with antimony or indium, or silicon oxide doped with nickel or boron can be used. The first dielectric layer 440 can be a substantially single-phase film, such as zinc stannate, a mixture of phases composed of zinc oxide and tin oxide, or can be composed of a plurality of films.

[0026] As shown in FIG. 5, the first dielectric layer 440 can include a multilayer structure having a first film 442 deposited on at least a part of the substrate (such as the inner main surface 16 of the first ply 12), for example, a metal alloy oxide film, and a second film 444 deposited on the first film 442, for example, a metal oxide or mixed oxide film. In one non-limiting embodiment, the first film 442 can be a zinc / tin alloy oxide. The term "zinc / tin alloy oxide" means both a true alloy and a mixture of oxides. The zinc / tin alloy oxide can be obtained from magnetron sputtering vacuum deposition from zinc and tin cathodes. One non-limiting cathode can include zinc and tin in a ratio of 5 wt% to 95 wt% zinc and 95 wt% to 5 wt% tin, for example, 10 wt% to 90 wt% zinc and 90 wt% to 10 wt% tin. However, other ratios of zinc and tin can also be used. One suitable metal alloy oxide that can be present in the first film 442 is zinc stannate. "Zinc stannate" means Zn X Sn 1-X O 2-X (the composition of formula (1), where "x" varies in the range greater than 0 and less than 1. For example, "x" can be greater than 0 and can be any fraction or decimal greater than 0 and less than 1. For example, when x = 2 / 3, formula 1 is Zn 2 / 3 0Sn 1 / 3 O 4 / 3 which is more generally described as "Zn 2 SnO 4 ". The zinc stannate-containing film has one or more of the forms of formula (1) in a major amount in the film.

[0027] The second film 444 can be a metal oxide film such as zinc oxide. Zinc oxide can be deposited from a zinc cathode containing other materials to improve the sputtering characteristics of the cathode. For example, the zinc cathode can contain a small amount (e.g., up to 20 wt%, up to 15 wt%, up to 10 wt% or up to 5 wt%) of tin to improve sputtering. In that case, the resulting zinc oxide film contains a small proportion of tin oxide, e.g., up to 10 wt% of tin oxide, e.g., up to 5 wt% of tin oxide. A coating layer deposited from a zinc cathode having up to 10 wt% tin (added to increase the conductivity of the cathode) is referred to herein as a "zinc oxide film" even if a small amount of tin may be present. A small amount of tin (e.g., up to 10 wt% such as up to 5 wt% or less) in the cathode is thought to mainly form tin oxide in the second film 44 of zinc oxide.

[0028] The first metal layer 446 can be deposited on the first dielectric layer 440. The first metal layer 446 can include a reflective metal such as, but not limited to, metallic gold, copper, palladium, aluminum, silver, or mixtures, alloys or combinations thereof. In one embodiment, the reflective metal is silver or copper. In another embodiment, the first metal layer 446 contains silver and copper. The first metal layer 446 can be a continuous layer. Alternatively, the first metal layer 446 can be a discontinuous layer. The first metal layer 446 can have a thickness of less than 250 Å, preferably less than 200 Å, more preferably less than 125 Å, most preferably less than 100 Å and / or greater than 50 Å, preferably greater than 60 Å, more preferably greater than 65 Å, most preferably greater than 70 Å. In one embodiment, the first metal layer 446 has a thickness of 78 Å to 121 Å. In another embodiment, the first metal layer 446 has a thickness of 70 Å to 99 Å.

[0029] Any first primer layer 448 can be disposed on the first metal layer 446. Any first primer layer 448 can be a single film or a plurality of film layers. Any first primer layer 448 can include an oxygen scavenging material that can be sacrificed during a deposition process to prevent degradation or oxidation of the first metal layer 446 during a sputtering process or a subsequent heating process. Any first primer layer 448 can also absorb at least a portion of electromagnetic radiation, such as visible light, passing through the coating 30. Examples of materials useful for any first primer layer 448 include titanium, silicon, silicon dioxide, silicon nitride, silicon oxynitride, nickel-chromium alloys (such as Inconel), zirconium, aluminum, alloys of silicon and aluminum, alloys containing cobalt and chromium (e.g., Stellite (registered trademark)), and mixtures thereof. For example, any first primer layer 448 can be titanium, or an alloy or mixture of titanium and aluminum.

[0030] The second dielectric layer 450 is disposed on the first metal layer 446 or on any first primer layer 448. The second dielectric layer 450 can include one or more metal oxide-containing films or metal alloy oxide-containing films such as those described above with respect to the first dielectric layer 440. For example, referring to FIG. 5, the second dielectric layer 450 includes a first film 452, e.g., a zinc oxide film deposited on the first metal layer 446 or any first primer film 448, and a second film 454, e.g., a zinc stannate (Zn 2 SnO 4 ) film deposited on the first film 452. Any third film 456, e.g., a second zinc oxide film, can be deposited on the second film.

[0031] The second metal layer 458 is disposed on the second dielectric layer 450 (e.g., on the second zinc oxide film 456 if present, or on the zinc stannate film 454 if not present). The metal material can be metallic gold, copper, palladium, aluminum, silver, or a mixture, alloy, or combination thereof. The metal material can be applied as a continuous layer or as a discontinuous layer such that isolated regions or islands of material, rather than a continuous layer of material, are formed. The second metal layer 458 can have a thickness greater than that of the first metal layer 446. The second metal layer 458 can have a thickness of at least 70 Å, preferably at least 100 Å, more preferably at least 125 Å, most preferably at least 128 Å and / or a maximum of 250 Å, preferably a maximum of 225 Å, more preferably a maximum of 200 Å, most preferably a maximum of 191 Å.

[0032] Any second primer layer 460 can be deposited on the second metal layer 458. Any second primer layer 460 can be as described above with respect to any first primer layer 448. In one example, any second primer layer 460 can be titanium. Any of the primer layers can be sputtered in a non-reactive atmosphere such as a low oxygen or oxygen-free atmosphere. The coated article can then be subjected to additional processing such as the deposition of an additional oxide layer in an oxygen-containing atmosphere. During this additional deposition, the primer oxidizes.

[0033] The third dielectric layer 462 can be deposited on the second metal layer 458 (e.g., on any second primer film 460). The third dielectric layer 462 can also include one or more metal oxide-containing layers or metal alloy oxide-containing layers as described above with respect to the first and second dielectric layers 440, 450. The third dielectric layer 462 can include a first film 464, e.g., a zinc oxide film, and a second film 466, e.g., a zinc stannate film deposited on the first film 464. Any third film 468, e.g., a second zinc oxide layer, can be deposited on the second film.

[0034] The third metal layer 470 is deposited on the third dielectric layer 462. The third metal layer 470 can be any of the materials described above with respect to the first metal layer 446. In a non-limiting example, the third metal layer 470 includes silver, copper, or both silver and copper. The third metal layer 470 is a continuous layer. Alternatively, the third metal layer 470 can be a discontinuous layer. The third metal layer 470 can be thinner than the second metal layer 458. The third metal layer can have a thickness of less than at least 250 Å, preferably less than 200 Å, more preferably less than 125 Å, most preferably less than 100 Å and / or greater than 50 Å, preferably greater than 60 Å, more preferably greater than 65 Å, most preferably greater than 70 Å. In one embodiment, the first metal layer 446 has a thickness of 97 Å to 105 Å. In another embodiment, the first metal layer 446 has a thickness of 70 Å to 125 Å.

[0035] Any third primer layer 472 is disposed on the third metal layer 470. Any third primer layer 472 can be as described above with respect to any first or second primer layer 448 or 460.

[0036] The fourth dielectric layer 474 is disposed on the third metal layer 470 (e.g., on any third primer layer 472). The fourth dielectric layer 474 can be composed of one or more metal oxide-containing layers or metal alloy oxide-containing layers such as those described above with respect to the first, second, or third dielectric layers 440, 450, 462. In a non-limiting example, the fourth dielectric layer 474 is a multilayer film having a first film 476 deposited on the third metal layer 470 or the third primer layer 472 and a second film 478 deposited on the first film 476. Any third film 479 can be deposited on the second film.

[0037] The fourth metal layer 492 is disposed on the fourth dielectric layer 474. The fourth metal layer 492 can include a reflective metal such as, but not limited to, metallic gold, copper, palladium, aluminum, silver, or mixtures, alloys, or combinations thereof. In one embodiment, the reflective metal is silver, copper, or a combination of silver and copper. In one embodiment, the fourth metal layer 492 contains silver and copper. The fourth metal layer 492 can be a continuous layer or a discontinuous layer. The fourth metal layer 492 can be thicker than the first metal layer 446. The fourth metal layer 492 can also be thicker than the third metal layer 470. The fourth metal layer can have a thickness of at least 100 Å, preferably at least 150 Å, more preferably at least 175 Å, most preferably at least 181 Å and / or a maximum of 300 Å, preferably a maximum of 275 Å, more preferably 250 Å, most preferably a maximum of 240 Å.

[0038] Any fourth primer layer 540 can be deposited on the fourth metal layer 492. The fourth primer layer 540 can be as described above with respect to any of the first primer layer 448, the second primer layer 460, or the third primer layer 472. In one example, any fourth primer layer 540 can be titanium.

[0039] The fifth dielectric layer 550 is disposed on the fourth metal layer 492 (e.g., on any fourth primer layer 540). The fifth dielectric layer 550 can be composed of one or more metal oxide-containing layers or metal alloy oxide-containing layers such as those described above with respect to the first, second, third, or fourth dielectric layers 440, 450, 462, 474. In a non-limiting example, the fifth dielectric layer 550 is a multilayer film having a first film 502 deposited on the fourth primer layer 540 or the fourth metal layer 492 and a second film 504 deposited on the first film 502.

[0040] In another non-limiting example, the fifth dielectric layer 550 has a first film 502 and a second film 504. The first film contains zinc oxide. The second film contains silicon nitride.

[0041] In another non-limiting example, the fifth dielectric layer 550 has a first film 502, a second film 504, and a third film (not shown). The first film 502 contains zinc oxide or zinc stannate. The second film 504 contains zinc stannate, silicon oxide, or silicon oxynitride. The third film contains silicon nitride. Silicon oxide, silicon oxynitride, and silicon nitride can contain aluminum such as aluminum oxide or aluminum nitride in an amount of up to 5 weight percent, up to 10 weight percent, up to 15 weight percent, or up to 20 weight percent. In one embodiment, the second film 504 and the third film are a gradient layer from silicon oxide or silicon oxynitride to silicon nitride.

[0042] An optional overcoat 480 can be disposed on the fifth dielectric layer 550. The overcoat 480 can serve to protect the underlying coating layer from mechanical and chemical attacks. The optional overcoat 480 can be, for example, a metal oxide layer or a metal nitride layer. For example, the optional overcoat 480 can be titania, or a mixture of titania and alumina. Other materials useful for the overcoat include other oxides such as silica, alumina, or a mixture of silica and alumina.

[0043] In a non-limiting embodiment, the transparent material has a visible light transmittance of greater than 20%, for example greater than 30%, for example greater than 34%. The transparent material has a solar heat gain coefficient (SHGC) of less than 0.3, for example less than 0.27, for example less than 0.25, for example less than or equal to 0.22, for example less than 0.20, for example less than 0.19 and / or at least 0.10, at least 0.12, at least 0.15, or at least 0.17. The transparent material has a ratio of light transmittance to solar heat gain coefficient (light to solar gain ratio) (LSG) of at least 1.7, at least 1.75, at least 1.8, or at least 1.85 and / or at most 2.25, at most 2.15, at most 2.10, or at most 2.06.

[0044] Any one of the first metal layer 446, the second metal layer 458, the third metal layer 470, and the fourth metal layer 492 can be a discontinuous layer. In one embodiment, only the second metal layer or only the third metal layer is a discontinuous layer. In another embodiment, only the third metal layer is a discontinuous layer. In another embodiment, only the second metal layer is a discontinuous layer.

[0045] The coated article can have a total thickness of all the metal layers (e.g., the total thickness is the sum of the thicknesses of the first, second, third, and fourth metal layers). This total thickness can range from 200 Å to 750 Å, preferably from 225 Å to 650 Å, more preferably from 250 Å to 600 Å, and most preferably from 252 Å to 582 Å. The coated article can have a total thickness of the all continuous metal layers (i.e., excluding the thickness of the discontinuous layer). The total thickness of all the continuous layers can range from 150 Å to 750 Å, preferably from 200 Å to 650 Å, more preferably from 225 Å to 575 Å, and most preferably from 237 Å to 563 Å.

[0046] The coated article can have a single discontinuous metal layer where all the other metal layers are continuous metal layers.

[0047] A primer, such as any of the above primers, can be disposed in direct contact on any of the metal layers. The primer can be a mixture of titanium and aluminum.

[0048] The present invention further relates to a method of making a coated article. The method includes providing a substrate. A first dielectric layer is applied over at least a portion of the substrate. A first metal layer is applied over at least a portion of the first dielectric layer. A second dielectric layer is applied over at least a portion of the first metal layer. A second metal layer is applied over at least a portion of the second dielectric layer. A third dielectric layer is applied over at least a portion of the second metal layer. A third metal layer is applied over at least a portion of the third dielectric layer. A fourth dielectric layer is applied over at least a portion of the fourth metal layer. A fifth dielectric layer is applied over at least a portion of the fourth metal layer. The first metal layer, the second metal layer, the third metal layer or the fourth metal layer is a discontinuous layer. An optional protective overcoat may be applied over the fifth dielectric layer. Optionally, a primer may be applied over the first metal layer, the second metal layer, the third metal layer and / or the fourth metal layer. In another embodiment, either the second or the third metal layer is a discontinuous layer.

[0049] Another embodiment of the present invention is a method of making a building transparent material. The method includes providing a first ply having a first surface and a second surface, and providing a second ply having a third surface and a fourth surface. Either the second surface of the first ply or the third surface of the second ply has a coating as described herein. The first ply and the second ply are assembled such that the second surface faces the third surface and there is a gap between the second surface and the third surface. The gap is filled with a gas. The gas can be air or argon.

[0050] In one embodiment, the discontinuous metal layer is the third metal layer. In such an embodiment, the coating can have a thickness for each layer as described in Table 1 or for each film as described in Table 2. In this embodiment, the third dielectric layer is thicker than the first dielectric layer, the second dielectric layer, the fourth dielectric layer and / or the fifth dielectric layer. The third dielectric layer also includes a third film.

[0051]

Table 1

[0052]

Table 2

[0053] In another embodiment, the discontinuous metal layer is the second metal layer. In such an embodiment, the coating can have a thickness for each layer as described in Table 3 or for each film as described in Table 4. In this embodiment, the fourth dielectric layer is thicker than the first dielectric layer, the second dielectric layer, the third dielectric layer, and / or the fifth dielectric layer. The fourth dielectric layer also includes the third film.

[0054]

Table 3

[0055]

Table 4

[0056] The following examples illustrate various embodiments of the present invention. However, it should be understood that the present invention is not limited to these specific embodiments.

Examples

[0057] Examples 1 to 4 were prepared by coating glass with the coating stack described in Table 5.

[0058]

Table 5

[0059] In Example 1, the LTA was 34.0, the SHGC was 0.183, and the LSG was 1.86. In Example 2, the LTA was 34.3, the SHGC was 0.178, and the LSG was 1.93. In Example 3, the LTA was 37.3, the SHGC was 0.182, and the LSG was 2.05. In Example 4, the LTA was 40.1, the SHGC was 0.22, and the LSG was 1.82.

[0060] Examples 5 to 7 were prepared by coating the glass with the coating stack described in Table 6.

[0061]

Table 6

[0062] Example 8 was prepared by coating the glass with the coating stack described in Table 7.

[0063]

Table 7

[0064] The present invention is further described in the following numbered clauses.

[0065] Clause 1: A coated article comprising a substrate; a first dielectric layer covering at least a part of the substrate; a first metal layer covering at least a part of the first dielectric layer; an optional first primer covering at least a part of the first metal layer; a second dielectric layer covering at least a part of the first primer layer; a second metal layer covering at least a part of the second dielectric layer; an optional second primer covering at least a part of the second metal layer; a third dielectric layer covering at least a part of the second primer layer; a third metal layer covering at least a part of the third dielectric layer; an optional third primer covering at least a part of the third metal layer; a fourth dielectric layer covering at least a part of the third primer layer; a fourth metal layer covering at least a part of the fourth dielectric layer; and an optional fourth primer covering at least a part of the fourth metal layer; a fifth dielectric layer covering at least a part of the fourth metal layer, wherein the first metal layer, the second metal layer, the third metal layer or the fourth metal layer is a discontinuous layer.

[0066] Clause 2: The article of Clause 1, wherein the optional first primer, the second primer, the optional third primer or the optional fourth primer is selected from titanium, a silicon-aluminum alloy, a nickel alloy, an alloy containing nickel and chromium, a cobalt alloy, an alloy containing cobalt and chromium, copper, aluminum, silicon, a nickel-chromium alloy, zirconium, mixtures thereof and alloys thereof.

[0067] Clause 3: The article of Clause 1 or 2, wherein the optional first primer, the optional second primer, the optional third primer or the fourth primer is deposited as a metal and then oxidized.

[0068] Clause 4: The article of any one of Clauses 1 to 3, wherein the discontinuous layer contains silver or copper.

[0069] Clause 5: The article of any one of Clauses 1 to 4, wherein the discontinuous layer contains silver and copper.

[0070] Clause 6: An article according to any one of Clauses 1 to 5, wherein the second dielectric layer or the third dielectric layer includes a zinc oxide layer and a zinc stannate layer covering the zinc oxide layer.

[0071] Clause 7: An article according to any one of Clauses 1 to 6, further including a protective coating covering the fifth dielectric layer.

[0072] Clause 8: An article according to any one of Clauses 1 to 7, wherein the first dielectric layer includes an oxide, nitride, or oxynitride of titanium, hafnium, zirconium, niobium, zinc, bismuth, lead, indium, tin, aluminum, silicon, or a mixture thereof.

[0073] Clause 9: An article according to any one of Clauses 1 to 8, wherein the second dielectric layer includes an oxide, nitride, or oxynitride of titanium, hafnium, zirconium, niobium, zinc, bismuth, lead, indium, tin, aluminum, silicon, or a mixture thereof.

[0074] Clause 10: An article according to any one of Clauses 1 to 9, wherein the third dielectric layer includes an oxide, nitride, or oxynitride of titanium, hafnium, zirconium, niobium, zinc, bismuth, lead, indium, tin, aluminum, silicon, or a mixture thereof.

[0075] Clause 11: An article according to any one of Clauses 1 to 10, wherein the fourth dielectric layer includes an oxide, nitride, or oxynitride of titanium, hafnium, zirconium, niobium, zinc, bismuth, lead, indium, tin, aluminum, silicon, or a mixture thereof.

[0076] Clause 12: An article according to any one of Clauses 1 to 11, wherein the fifth dielectric layer includes an oxide, nitride, or oxynitride of titanium, hafnium, zirconium, niobium, zinc, bismuth, lead, indium, tin, silicon, aluminum, or a mixture thereof.

[0077] Clause 13: An article according to any one of Clauses 1 to 12, wherein the first dielectric layer, the second dielectric layer, the third dielectric layer, and / or the fourth dielectric layer includes zinc oxide.

[0078] Clause 14: An article according to any one of Clauses 1 to 13, wherein the first dielectric layer, the second dielectric layer, the third dielectric layer and / or the fourth dielectric layer contains zinc stannate.

[0079] Clause 15: An article according to any one of Clauses 1 to 14, wherein the fifth dielectric layer contains zinc oxide or zinc stannate.

[0080] Clause 16: An article according to any one of Clauses 1 to 15, wherein the fifth dielectric layer contains silicon oxide, silicon nitride, silicon oxynitride or a mixture thereof.

[0081] Clause 17: An article according to any one of Clauses 1 to 16, wherein the first dielectric layer includes a first film containing zinc stannate covering a substrate and a second film containing zinc oxide covering the first film.

[0082] Clause 18: An article according to any one of Clauses 1 to 17, wherein the second dielectric layer includes a first film containing zinc oxide and a second film containing zinc stannate.

[0083] Clause 19: An article according to any one of Clauses 1 to 18, wherein the third dielectric layer includes a first film containing zinc oxide, a second film containing zinc stannate, and an optional third film containing zinc oxide.

[0084] Clause 20: An article according to any one of Clauses 1 to 19, wherein the fourth dielectric layer includes a first film of zinc stannate and a second film of zinc oxide.

[0085] Clause 21: An article according to any one of Clauses 1 to 20, wherein the fifth dielectric layer includes a first film containing zinc oxide or zinc stannate.

[0086] Clause 22: An article according to any one of Clauses 1 to 21, wherein the fifth dielectric layer further includes a second film containing silicon oxide, silicon oxynitride, silicon nitride or a mixture thereof.

[0087] Clause 23: The article according to Clause 22, wherein the second film is a gradient layer from silicon oxide to silicon nitride.

[0088] Clause 24: The article of Clause 22, wherein the second film is a gradient layer from silicon oxynitride to silicon nitride.

[0089] Clause 25: The article of any one of Clauses 1 to 24, wherein the first metal film comprises metallic gold, copper, palladium, aluminum, silver, or a mixture, alloy, or combination thereof.

[0090] Clause 26: The article of any one of Clauses 1 to 25, wherein the second metal film comprises metallic gold, copper, palladium, aluminum, silver, or a mixture, alloy, or combination thereof.

[0091] Clause 27: The article of any one of Clauses 1 to 26, wherein the third metal film comprises metallic gold, copper, palladium, aluminum, silver, or a mixture, alloy, or combination thereof.

[0092] Clause 28: The article of any one of Clauses 1 to 27, wherein the fourth metal film comprises metallic gold, copper, palladium, aluminum, silver, or a mixture, alloy, or combination thereof.

[0093] Clause 29: The article of any one of Clauses 1 to 28, wherein the first metal film comprises copper, silver, or a mixture thereof.

[0094] Clause 30: The article of any one of Clauses 1 to 29, wherein the second metal film comprises copper, silver, or a mixture thereof.

[0095] Clause 31: The article of any one of Clauses 1 to 30, wherein the third metal film comprises copper, silver, or a mixture thereof.

[0096] Clause 32: The article of any one of Clauses 1 to 31, wherein the fourth metal film comprises copper, silver, or a mixture thereof.

[0097] Clause 33: The article of any one of Clauses 1 to 34, wherein the first primer, the second primer, the third primer, and / or the fourth primer comprises titanium, aluminum, or a mixture thereof, the primer is deposited as a metal, and is at least partially oxidized by depositing the next layer on the primer.

[0098] Clause 34: An article according to any one of Clauses 1 to 33, wherein the second metal layer or the third metal layer is a discontinuous layer.

[0099] Clause 35: An article according to Clause 34, wherein the discontinuous layer has a thickness of at most 36 Å, preferably at most 26 Å, more preferably at most 20 Å, most preferably at most 19 Å, and at least 5 Å, preferably at least 7 Å, more preferably at least 10 Å, most preferably at least 15 Å.

[0100] Clause 36: An article according to Clause 34 or 35, wherein the second metal layer is a discontinuous layer.

[0101] Clause 37: An article according to Clause 34 or 35, wherein the third metal layer is a discontinuous layer.

[0102] Clause 38: An article according to Clause 34, 35, 36 or 37, wherein at least two of the metal layers are continuous metal layers.

[0103] Clause 39: An article according to Clause 34, 35 or 36, wherein the first metal layer and the fourth metal layer are continuous metal layers, the first metal layer has a thickness of less than 250 Å, preferably less than 200 Å, more preferably less than 125 Å, most preferably less than 100 Å and / or more than 50 Å, preferably more than 60 Å, more preferably more than 65 Å, most preferably more than 70 Å, and the fourth metal layer has a thickness of at least 100 Å, preferably at least 150 Å, more preferably at least 175 Å, most preferably at least 181 Å and / or at most 300 Å, preferably at most 275 Å, more preferably 250 Å, most preferably at most 240 Å.

[0104] Clause 40: An article according to Clause 34, 35 or 36, wherein three of the metal layers are continuous metal layers.

[0105] Clause 41: The continuous metal layers are the first metal layer, the second metal layer, and the fourth metal layer. The first metal layer has a thickness of less than 250 Å, preferably less than 200 Å, more preferably less than 125 Å, most preferably less than 100 Å and / or greater than 50 Å, preferably greater than 60 Å, more preferably greater than 65 Å, most preferably greater than 70 Å. The fourth metal layer has a thickness of at least 100 Å, preferably at least 150 Å, more preferably at least 175 Å, most preferably at least 181 Å and / or at most 300 Å, preferably at most 275 Å, more preferably 250 Å, most preferably at most 240 Å. The second metal layer has a thickness of at least 70 Å, preferably at least 100 Å, more preferably at least 125 Å, most preferably at least 128 Å and / or at most 250 Å, preferably at most 225 Å, more preferably at most 200 Å, most preferably at most 191 Å, the article of Clause 40.

[0106] Clause 42: The continuous metal layers are the first metal layer, the third metal layer, and the fourth metal layer. The first metal layer has a thickness of less than 250 Å, preferably less than 200 Å, more preferably less than 125 Å, most preferably less than 100 Å and / or greater than 50 Å, preferably greater than 60 Å, more preferably greater than 65 Å, most preferably greater than 70 Å. The fourth metal layer has a thickness of at least 100 Å, preferably at least 150 Å, more preferably at least 175 Å, most preferably at least 181 Å and / or at most 300 Å, preferably at most 275 Å, more preferably 250 Å, most preferably at most 240 Å, the article of Clause 40.

[0107] Clause 43: The continuous metal layers have a thickness in the range of 50 Å to 300 Å, preferably 60 Å to 250 Å, more preferably 65 Å to 225 Å, most preferably 71 Å to 205 Å, of any of the articles of Clauses 34 to 42.

[0108] Clause 44: The article has an LTA of 30 to 45, preferably 32 to 43, more preferably 33 to 43, most preferably 34 to 41, of any of the articles of Clauses 1 to 43.

[0109] Clause 45: An article according to any one of Clauses 1 to 44, wherein the article has a SHGC of 0.170 to 0.200, preferably 0.174 to 0.250, more preferably 0.175 to 0.230, and most preferably 0.178 to 0.220.

[0110] Clause 46: An article according to any one of Clauses 1 to 45, wherein the article has an LSG of 1.50 to 2.50, preferably 1.70 to 2.25, more preferably 1.75 to 2.15, and most preferably 1.82 to 2.05.

[0111] Clause 47: A coated article having a substrate, a first dielectric film, a second dielectric film covering the first dielectric film, a first metal film covering the second dielectric film and containing silver, a third dielectric film covering the first metal film, a fourth dielectric film covering the third dielectric film, a second metal layer covering the fourth dielectric film and containing silver, a fifth dielectric film covering the second metal film, a sixth dielectric film covering the fifth dielectric film, a third metal layer covering the sixth dielectric film and containing silver, a seventh dielectric film covering the third metal film, an eighth dielectric film covering the seventh dielectric film, a fourth metal film covering the eighth dielectric film and containing silver, and a ninth dielectric film covering the fourth metal film, wherein the first metal film, the second metal film, the third metal film or the fourth metal film is a discontinuous film.

[0112] Clause 48: A coated article according to Clause 47, wherein the first dielectric film contains zinc stannate.

[0113] Clause 49: A coated article according to any one of Clauses 47 to 48, wherein a plurality of primers are disposed in direct contact on each metal film.

[0114] Clause 51: A coated article according to any one of Clauses 47 to 50, wherein the second metal film is a discontinuous layer.

[0115] Clause 52: A coated article according to any one of Clauses 47 to 50, wherein the third metal film is a discontinuous layer.

[0116] Clause 53: A coated article of any of Clauses 47 to 52, wherein at least two of the metal films are continuous layers.

[0117] Clause 54: A coated article of any of Clauses 47 to 52, wherein at least three of the metal films are continuous layers.

[0118] Clause 55: A coated article of any of Clauses 47 to 54, further comprising a protective layer covering the ninth dielectric film.

[0119] Clause 56: An article of any of Clauses 47 to 55, wherein the article has an LTA of 30 to 45, preferably 32 to 43, more preferably 33 to 43, and most preferably 34 to 41.

[0120] Clause 57: An article of any of Clauses 47 to 56, wherein the article has an SHGC of 0.170 to 0.200, preferably 0.174 to 0.250, more preferably 0.175 to 0.230, and most preferably 0.178 to 0.220.

[0121] Clause 58: An article of any of Clauses 47 to 57, wherein the article has an LSG of 1.50 to 2.50, preferably 1.70 to 2.25, more preferably 1.75 to 2.15, and most preferably 1.82 to 2.05.

[0122] Clause 59: A method of making a coated article comprising providing a substrate, applying a first dielectric layer over at least a portion of the substrate, applying a first metal layer over at least a portion of the first dielectric layer, applying a second dielectric layer over at least a portion of the first metal layer, applying a second metal layer over at least a portion of the second dielectric layer, applying a third dielectric layer over at least a portion of the second metal layer, applying a third metal layer over at least a portion of the third dielectric layer, applying a fourth dielectric layer over at least a portion of the fourth metal layer, applying a fifth dielectric layer over at least a portion of the fourth metal layer, wherein the first metal layer, the second metal layer, the third metal layer or the fourth metal layer is a discontinuous layer.

[0123] Clause 60: The method of clause 59, further comprising applying a protective overcoat over at least a portion of the fifth dielectric layer.

[0124] Clause 61: The method of clause 59 or 60, further comprising applying a primer layer over at least a portion of the first metal layer, the second metal layer, the third metal layer and / or the fourth metal layer, wherein the primer layer is applied as a metal and is oxidized upon application of the next layer.

[0125] Clause 62: The method according to any one of clauses 59 to 61, wherein at least the first metal layer is a continuous metal layer.

[0126] Clause 63: The method according to any one of clauses 59 to 62, wherein at least the fourth metal layer is a continuous metal layer.

[0127] Clause 64: The method according to any one of clauses 59 to 63, wherein the third metal layer is a discontinuous metal layer.

[0128] Clause 65: The method according to any one of clauses 59 to 63, wherein the second metal layer is a discontinuous metal layer.

[0129] Article 66: An architectural transparent material including a first ply having a first surface and a second surface, a second ply having a third surface and a fourth surface, and a coating disposed on at least a part of the second surface or the third surface, wherein the coating includes the coating provided in any one of Articles 1 to 58.

[0130] Article 67: The architectural transparent material according to Article 66, further including a space between the second surface and the third surface, and the space is filled with a gas.

[0131] Article 68: The architectural transparent material according to Article 67, wherein the gas is argon.

[0132] Article 69: The architectural transparent material according to any one of Articles 66 to 68, wherein the first surface is configured to face the outside of the structure where the architectural transparent material is installed.

[0133] Article 70: The architectural transparent material according to any one of Articles 66 to 69, wherein the fourth surface is configured to face the inside of the structure where the architectural transparent material is installed.

[0134] Article 71: A method of manufacturing an architectural transparent material, including providing a first ply having a first surface and a second surface, providing a second ply having a third surface and a fourth surface, wherein either the second surface of the first ply or the third surface of the second ply includes a coating provided in any one of Articles 1 to 58, assembling the first ply and the second ply such that the second surface faces the third surface and there is a space between the second surface and the third surface, and the space is filled with a gas.

[0135] Article 72: The method according to Article 71, wherein the gas is argon.

[0136] Those skilled in the art will readily understand that modifications can be made to the present invention without departing from the concepts disclosed in the foregoing description. Accordingly, the specific embodiments described in detail herein are merely illustrative and do not limit the scope of the present invention, which is intended to cover the full scope of the appended claims and all equivalents thereof.

Claims

1. A substrate; a first dielectric layer having a thickness in the range of 300 Å to 525 Å covering at least a portion of the substrate; a first metal layer having a thickness in the range of 60 Å to 150 Å covering at least a portion of the first dielectric layer; a first primer layer having a thickness in the range of 15 Å to 45 Å covering at least a portion of the first metal layer; a second dielectric layer having a thickness in the range of 400 Å to 1000 Å covering at least a portion of the first primer layer; a second metal layer having a thickness in the range of 70 Å to 250 Å covering at least a portion of the second dielectric layer; a second primer layer having a thickness in the range of 15 Å to 45 Å covering at least a portion of the second metal layer; a third dielectric layer having a thickness in the range of 100 Å to 600 Å covering at least a portion of the second primer layer; a third metal layer having a thickness in the range of 10 Å to 25 Å covering at least a portion of the third dielectric layer; a third primer layer having a thickness in the range of 15 Å to 45 Å covering at least a portion of the third metal layer; a fourth dielectric layer having a thickness in the range of 250 Å to 700 Å covering at least a portion of the third primer layer; a fourth metal layer having a thickness in the range of 60 Å to 275 Å covering at least a portion of the fourth dielectric layer; a fourth primer layer having a thickness in the range of 15 Å to 45 Å covering at least a portion of the fourth metal layer; a fifth dielectric layer having a thickness in the range of 175 Å to 450 Å covering at least a portion of the fourth primer layer; an overcoat having a thickness in the range of 30 Å to 60 Å covering at least a portion of the fifth dielectric layer; A coated article having a tinted appearance in reflection and / or transmission, comprising: the third metal layer being a discontinuous layer; the coated article having an SHGC of 0.170 to 0.200; The coated article.

2. 2. The article of claim 1, wherein the first primer layer, the second primer layer, the third primer layer, and / or the fourth primer layer are selected from titanium, silicon-aluminum alloys, nickel alloys, alloys containing nickel and chromium, cobalt alloys, alloys containing cobalt and chromium, copper, aluminum, silicon, nickel-chromium alloys, zirconium, mixtures thereof, and alloys thereof.

3. The article of claim 1 or 2, wherein the discontinuous layer comprises silver or copper.

4. 4. The article of claim 1, wherein the second dielectric layer or the third dielectric layer comprises a zinc oxide layer and a zinc stannate layer overlying the zinc oxide layer.

5. 5. The article of claim 1, wherein the third metal layer has a thickness of less than 20 Å.

6. 6. The article of claim 1, wherein the article comprises only one discontinuous layer.

7. 10. The article of claim 1 having an LTA of 30 to 45 and an LSG of 1.50 to 2.50.

Images