Patent Description:
IG window units are known in the art. For example, see <CIT>, <CIT>; <CIT>; <CIT>; <CIT>; <CIT>;<CIT>; <CIT>; and <CIT>. An IG window unit typically includes at least first and second substrates spaced apart from one another by at least one spacer and/or seal. The gap or space between the spaced apart substrates may or may not be filled with a gas (e.g., argon) and/or evacuated to a pressure less than atmospheric pressure in different instances.

Many conventional IG window units include a solar management coating (e.g., multi-layer coating for reflecting at least some infrared radiation) on an interior surface of one of the two substrates. Such IG units enable significant amounts of infrared (IR) radiation to be blocked so that it does not reach the interior of the building (apartment, house, office building, or the like).

Unfortunately, bird collisions with such windows represent a significant problem. For instance, in Chicago certain buildings (e.g., skyscrapers) are located in migratory bird paths. Birds flying along these paths repeatedly run into these buildings because they cannot see the windows of the building. This results in thousands of bird deaths, especially during seasons of bird migration. Birds living in environments such as forests or park areas, with buildings located in such areas, face similar problems associated with flying into the buildings.

Conventional ways of reducing bird collisions with windows include the use of nets, decals, or frit. However, these solutions are considered ineffective because of the aesthetic impact on the architecture and/or because they do not work as they do not make the glass more visible to birds.

<CIT> discloses a window for reducing bird collisions. However, while the window of the `<NUM> patent is effective for preventing/reducing bird collisions, there is room for improvement.

<CIT> discloses an IG window unit for reducing bird collisions, as shown for example in prior art <FIG>. The IG window unit in <FIG> includes first glass substrate <NUM> and second glass substrate <NUM> that are spaced apart from one another at least by one or more peripheral seal(s) or spacer(s) <NUM>. The spacer(s) <NUM>, other spacer(s), and/or peripheral seal space the two substrates <NUM> and <NUM> apart from one another so that the substrates do not contact one another and so that a space or air gap <NUM> is defined therebetween. Air gap <NUM> may or may not be filled with gas such as argon. A solar management coating <NUM> (e.g., low-E coating) and a UV reflecting coating <NUM> are provided on the same glass substrate <NUM>. However, the IG window unit of the '<NUM> patent is made up of two glass substrates spaced apart from each other via an air gap, and there is no lamination film. Thus, the IG window unit of the '<NUM> patent may suffer from a less than desirable contrast ratio between areas with the UV reflecting film and areas without the UV reflecting film. Thus, there is room for improvement. <CIT> and <CIT> discloses IG window units for reducing bird collisions.

In view of the above, it will be appreciated that there exists a need in the art for improved windows which can prevent or reduce bird collisions therewith.

In this invention, a window is designed to prevent or reduce bird collisions therewith. The window comprises an insulating glass (IG) window unit designed to prevent or reduce bird collisions therewith. The IG window unit includes at least first, second and third substrates (e.g., glass substrates) spaced apart from one another, wherein at least one of the substrates supports an ultraviolet (UV) reflecting coating for reflecting UV radiation so that birds are capable of more easily seeing the window, and wherein at least two of the substrates are laminated to one another via a polymer-based laminating film (e.g., of or including PVB, EVA, or SGP). The UV reflecting coating is patterned so that it is not provided across the entirety of the IG window unit. By making the window more visible to birds, bird collisions and bird deaths can be reduced. The provision of the laminated substrates in the IG window unit is particularly advantageous for bird collision windows, because it: (a) increases the contrast ratio of the IG window unit between areas having the UV reflecting coating and areas not having the UV reflecting coating, thereby making the window more visible to birds and reducing the likelihood of bird collisions, (b) increases mechanical durability of the IG window unit and reduces the likelihood of glass cracking due to bird collisions, and (c) in certain embodiments allows two single-coated-side glass substrates to be provided which improves production durability and processing so as to reduce likelihood of coating damage during processing, manufacturing, and/or shipping.

In this invention, there is provided an IG window unit comprising: a first glass substrate; a second glass substrate; a third glass substrate; wherein the first glass substrate is provided at an exterior side of the IG window unit so as to face an exterior of a building in which the IG window unit is to be mounted; wherein the second glass substrate is provided between at least the first and third glass substrates; wherein the third glass substrate is provided at an interior side of the IG window unit so as to face an interior of a building in which the IG window unit is to be mounted; a patterned UV reflecting coating provided on the first glass substrate and on an exterior surface of the IG window unit so as to face an exterior of a building in which the IG window unit is to be mounted; wherein the first and second glass substrates are laminated to each other via a polymer inclusive laminating film; a low-E coating provided on a side of the second glass substrate opposite the polymer inclusive laminating film, so that the second glass substrate is located between the low-E coating and the polymer inclusive laminating film; wherein the first glass substrate is located between the patterned UV reflecting coating and the polymer inclusive laminating film; wherein the UV reflecting coating is not part of a low-E coating and does not contain any IR reflecting layer of silver or gold; and wherein the second glass substrate is spaced apart from the third glass substrate via at least an air gap, so that a laminated structure including the first glass substrate, the second glass substrate, and the polymer inclusive laminating film is located on an outboard side of the air gap and on an outboard side of the low-E coating.

In an example embodiment, not part of this invention, there is provided an IG window unit comprising: a first glass substrate; a second glass substrate; a third glass substrate; wherein the first glass substrate is provided at an exterior side of the IG window unit so as to face an exterior of a building in which the IG window unit is to be mounted; wherein the second glass substrate is provided between at least the first and third glass substrates; wherein the third glass substrate is provided at an interior side of the IG window unit so as to face an interior of a building in which the IG window unit is to be mounted; a patterned UV reflecting coating provided on the first glass substrate and on an exterior surface of the IG window unit so as to face an exterior of a building in which the IG window unit is to be mounted; wherein the second and third glass substrates are laminated to each other via a polymer inclusive laminating film; a low-E coating provided on either the second glass substrate or on a side of the first glass substrate opposite the UV reflecting coating, so that the first glass substrate is located between the low-E coating and the UV reflecting coating, and so that the second glass substrate is located between the polymer inclusive laminating film and the low-E coating; wherein the first glass substrate is spaced apart from the second glass substrate via at least an air gap, so that a laminated structure including the second glass substrate, the third glass substrate, and the polymer inclusive laminating film is located on an inboard side of the air gap and on an inboard side of the low-E coating.

Referring now more particularly to the accompanying drawings in which like reference numerals indicate like parts throughout the several views.

The difference between color vision of a bird and human is significant. A bird's visual receptor may be around <NUM> which means that birds can generally see efficiently in the UV range. Using this difference, it is possible to make a coating that efficiently reflects UV (making it visible to birds) while being substantially neutral/invisible to human eyes Thus, the UV coating may be designed to have essentially the same or a similar reflectance characteristic as bare glass, so as to be substantially invisible to humans.

A window is designed to prevent or reduce bird collisions therewith. The window comprises an insulating glass (IG) window unit designed to prevent or reduce bird collisions therewith. The IG window unit includes at least first (<NUM>), second (<NUM>) and third (<NUM>) glass substrates spaced apart from one another, wherein the first substrate <NUM> as shown in <FIG> supports an ultraviolet (UV) reflecting coating <NUM> for reflecting UV radiation so that birds are capable of more easily seeing the window. At least two of the substrates are laminated to one another via a polymer-based laminating film (e.g., of or including PVB, EVA, or SGP) <NUM>. The polymer-based laminating film <NUM> is preferably of a type that has a high absorption of UV, for example a film <NUM> that has a UV absorption from <NUM>-<NUM> of at least <NUM>%, more preferably of at least <NUM>%, and most preferably at least <NUM>%. Note that this is not a typical feature of laminating films such as PVB, because certain PVB films for example do not have a high UV absorption (while others do). For instance, substrates <NUM> and <NUM> are laminated to each other in the <FIG> embodiment, and substrates <NUM> and <NUM> are laminated to each other in the <FIG> embodiment via laminating film <NUM>. The UV reflecting coating <NUM> is patterned so that it is not provided across the entirety of the IG window unit. By making the window more visible to birds, bird collisions and bird deaths can be reduced. Example embodiments of this invention provide a new IGU configuration with laminated glass to further increase the contrast ratio between areas with UV reflecting coating and areas without the UV reflecting coating. For example, PVB used in laminated glass can absorb much of UV wavelengths between <NUM> and <NUM>, thereby increasing contrast ratio between areas with UV reflecting coating <NUM> and areas without the UV reflecting coating <NUM>. The provision of the laminated substrates, via laminating film <NUM>, in the IG window unit is particularly advantageous for bird collision windows, because it: (a) increases the contrast ratio of the IG window unit between areas having the UV reflecting coating and areas not having the UV reflecting coating, thereby making the window more visible to birds and reducing the likelihood of bird collisions, (b) increases mechanical durability of the IG window unit and reduces the likelihood of glass cracking due to bird collisions, and (c) in certain embodiments allows two single-coated-side glass substrates to be provided which improves production durability and processing so as to reduce likelihood of coating damage during processing, manufacturing, and/or shipping.

Referring to <FIG> for example, a pair of spaced apart substrates may be separated from one another by at least one seal and/or spacer <NUM> in certain example embodiment. According to the invention, there is provided a low-E coating <NUM> for blocking at least some infrared (IR) radiation and a UV reflecting blocking coating <NUM> for reflecting UV radiation to make the window more visible to birds in order to reduce collisions. In certain example embodiments, the low-E coating <NUM> may have an emissivity (En) of no greater than <NUM> and/or a sheet resistance (Rs) of no greater than <NUM> ohms/square. In certain example embodiments, the UV reflecting coating <NUM> may block at least <NUM>% (more preferably at least <NUM>%, more preferably at least <NUM>%, even more preferably at least <NUM>%, and possibly at least <NUM>%) of UV radiation in at least a substantial part of the range from <NUM> to <NUM> (or alternatively in a substantial part of the range from <NUM>-<NUM>). This is significant UV blockage/reflection, and represents a significant advantage over coatings described in <CIT> for example and without limitation. This increases the UV reflection of the window unit intended for commercial or residential applications in order to make such windows more visible to birds thereby preventing or reducing bird collisions. The use of such coatings herein enhances the performance of the glass or window by increasing the UV reflectance beyond the normal limits of raw uncoated plate glass in the <NUM>-<NUM> range of the spectrum. According to the invention, the UV reflecting/blocking coating <NUM> is patterned (e.g., in a grid pattern or in a parallel striped pattern) on the window unit which can make it even more visible to birds to further reduce bird collisions. The IG window unit preferably has a visible transmission of at least about <NUM>%, more preferably of at least about <NUM>%, and even more preferably of at least about <NUM>% or at least about <NUM>%. Monolithic coated articles having only the coating <NUM> on a glass substrate <NUM> (e.g., see <FIG>) may have: (a) a visible transmission of at least about <NUM>%, more preferably of at least about <NUM>%, and even more preferably of at least about <NUM>%, (b) the film side UV reflectance of at least <NUM>% (more preferably at least <NUM>%, more preferably at least <NUM>%, even more preferably at least <NUM>%, and possibly at least <NUM>%), and (c) a film side visible reflectance of less than about <NUM>%, more preferably less than about <NUM>%, and most preferably less than about <NUM>%. Thus, the film side UV reflectance may be at least about <NUM> times higher than the film side visible reflectance of the monolithic coated article (more preferably at least about <NUM> times higher, even more preferably at least about <NUM> times higher, and possibly at least <NUM> times higher).

<FIG> are cross sectional views of a portion of an IG window unit. The IG window unit includes glass substrate <NUM>, glass substrate <NUM>, and glass substrate <NUM>. In the <FIG> embodiment, not part of the invention, glass substrate <NUM> and glass substrate <NUM> are spaced apart from one another at least by one or more peripheral seal(s) or spacer(s) <NUM>, so as to define an air gap <NUM> therebetween. The UV reflecting coating <NUM> is provided on the outboard side of glass substrate <NUM>, and the low-E coating <NUM> is provided on the inboard side of substrate <NUM>. The air gap may or may not be filled with a gas such as argon gas. Optionally, an array of spacers (not shown) may be provided between the substrates <NUM> and <NUM> in <FIG> in a viewing area of the window for spacing the substrates from one another as in the context of a vacuum IG window unit. The spacer(s) <NUM>, other spacer(s), and/or peripheral seal space the two substrates <NUM> and <NUM> in <FIG> apart from one another so that the substrates do not contact one another and so that a space or gap <NUM> is defined therebetween. The space <NUM> between the substrates <NUM>, <NUM> may be evacuated to a pressure lower than atmospheric in certain example embodiments, and/or may be filled with a gas (e.g., Ar) in certain example embodiments. In certain example embodiments, it is possible to suspend foil or other radiation reflective sheet(s) (not shown) in space <NUM>. Glass substrates <NUM> and <NUM> are laminated to each other via laminating film <NUM>, on the inboard side (side to be closest to the building interior) of the air gap <NUM> in the <FIG> embodiment. The polymer based laminating film <NUM> preferably absorbs UV, and may be of or include PVB (polyvinyl butyral), EVA, SGP (Sentry Glass Plus), or the like in different example embodiments of this invention. When substrate(s) <NUM>, <NUM> and <NUM> are of glass, each glass substrate may be of the soda-lime-silica type of glass, or any other suitable type of glass, and may be for example from about <NUM> to <NUM> thick in certain example embodiments of this invention.

Similarly, in the <FIG> embodiment, according to this invention, glass substrate <NUM> and glass substrate <NUM> are spaced apart from one another at least by one or more peripheral seal(s) or spacer(s) <NUM>, so as to define an air gap <NUM> therebetween. The UV reflecting coating <NUM> is provided on the outboard side of glass substrate <NUM> closest to the building exterior, and the low-E coating <NUM> is provided on the inboard side of substrate <NUM>. The air gap <NUM> may or may not be filled with a gas such as argon gas. Optionally, an array of spacers (not shown) may be provided between the substrates <NUM> and <NUM> in <FIG> in a viewing area of the window for spacing the substrates from one another as in the context of a vacuum IG window unit. The spacer(s) <NUM>, other spacer(s), and/or peripheral seal space the two substrates <NUM> and <NUM> in <FIG> apart from one another so that the substrates do not contact one another and so that a space or gap <NUM> is defined therebetween. The space <NUM> between the substrates <NUM>, <NUM> may be evacuated to a pressure lower than atmospheric in certain example embodiments, and/or may be filled with a gas (e.g., Ar) in certain example embodiments. In certain example embodiments, it is possible to suspend foil or other radiation reflective sheet(s) (not shown) in space <NUM>. In the <FIG> embodiment, glass substrates <NUM> and <NUM> are laminated to each other via polymer based laminating film <NUM>, on the outboard side (side to be closest to the building exterior) of the air gap <NUM>. The polymer based laminating film <NUM> preferably absorbs UV, and may be of or include PVB, EVA, SGP, or the like. Thus, <FIG> and <FIG> differ from each other mainly in that (i) the laminated structure is provided on the inboard side of the air gap17 and on the inboard side of the low-E coating <NUM> in <FIG>, but is provided on the outboard side of the air gap <NUM> and low-E coating <NUM> in <FIG>, and (ii) <FIG> provides for a structure allowing two single-coated-side glass substrates <NUM> and <NUM> to be provided which improves production durability and processing so as to reduce likelihood of coating damage during processing, manufacturing, and/or shipping. With respect to point (ii), in <FIG> glass substrate <NUM> is only coated on one side with UV coating <NUM>, and glass substrate <NUM> is only coated on one side with low-E coating <NUM>, in the manufacturing process (laminating film <NUM> is an interlayer for laminating/adhering purposes and is not a film that is sputter-deposited or otherwise deposited onto a surface of a substrate). In contrast, the <FIG> embodiment requires that both sides of glass substrate <NUM> be coated, one side with the UV coating <NUM> and the other side with the low-E coating, which can increase risk of damage during processing, shipping, and/or handling.

The IG window units of <FIG> include low-E coating <NUM> that is supported on an inboard side of glass substrate <NUM> (<FIG>) or on an inboard side of glass substrate <NUM> (<FIG>). Low-E coating <NUM> includes one or more layers, although in many embodiments it is a multi-layer coating. Low-E coating <NUM> includes at least one IR reflecting layer (e.g., based on silver or gold) sandwiched between at least first and second dielectric layers. Since one example function of low-E coating <NUM> is to block (i.e., reflect and/or absorb) certain amounts of IR radiation and prevent the same from reaching the building interior, the solar management coating <NUM> includes at least one IR blocking (i.e., IR reflecting and/or absorbing) layer. Example IR blocking layer(s) which may be present in coating <NUM> are of or include silver (Ag), nickel-chrome (NiCr), gold (Au), and/or any other suitable material that blocks significant amounts of IR radiation. It will be appreciated by those skilled in the art that IR blocking layer(s) of low-E coating <NUM> need not block all IR radiation, but only need to block significant amounts thereof. In certain embodiments, each IR blocking layer of coating <NUM> is provided between at least a pair of dielectric layers. Example dielectric layers include silicon nitride, titanium oxide, silicon oxynitride, tin oxide, and/or other types of metal-oxides and/or metal-nitrides. In certain embodiments, in addition to being between a pair of dielectric layers, each IR blocking layer may also be provided between a pair of contact layers of or including a material such as an oxide and/or nitride of nickel-chrome or any other suitable material. Example low-E coatings <NUM> are described in <CIT>,<CIT>, <CIT>, <CIT>, <CIT>, <CIT>, <CIT>, <CIT>,<CIT>, <CIT>, <CIT>, <CIT>, <CIT>, <CIT>, <CIT>, <CIT>.

In certain example embodiments, before and/or after optional heat treatment (e.g., thermal tempering and/or heat bending), the low-E coating <NUM> may have a sheet resistance (Rs) of no greater than <NUM> ohms/square, more preferably no greater than <NUM> ohms/square, and most preferably no greater than <NUM> ohms/square. In certain embodiments, the low-E coating <NUM> may have an emissivity (En) after heat treatment of no greater than <NUM>, more preferably no greater than <NUM>, and even more preferably no greater than <NUM> (before and/or after optional heat treatment). Of course, solar management coatings <NUM> herein are not limited to these particular coatings, and any other suitable solar management coatings capable of blocking amounts of IR radiation may instead be used. Solar management coatings <NUM> herein may be deposited on substrate(s) <NUM> and/or <NUM> in any suitable manner, including but not limited to sputtering, vapor deposition, and/or any other suitable technique.

Still referring to <FIG>, the IG window units further include UV reflecting coating <NUM> for reflecting significant amounts of UV radiation thereby making the window more visible to birds. Coatings <NUM> may be sputter-deposited in example embodiments of this invention. UV reflecting coating <NUM> may be, for purposes of example and without limitation, any of the UV reflecting coatings illustrated in <FIG>. This increases the UV reflection of the window unit in order to make such windows more visible to birds thereby preventing or reducing bird collisions. The use of such coatings <NUM> herein enhances the performance of the glass or window by increasing the UV reflectance beyond the normal limits of raw uncoated plate glass in the <NUM>-<NUM> range of the spectrum. The UV reflecting coating <NUM> is in direct contact with the glass substrate <NUM> on the exterior surface thereof, and is not part of a low-E coating <NUM>. In particular, there are no IR reflecting layers (e.g., silver based, gold based, NiCr, or IR reflecting TCO-based layers) in coating <NUM>, and there are no IR reflecting layers on the side of the substrate <NUM> on which the coating <NUM> is provided. Instead, the low-E coating is provided on the other side of substrate <NUM> from coating <NUM> (not part of this invention) or alternatively on substrate <NUM> (according to this invention). In certain example embodiments, the UV reflecting coating <NUM> may block at least <NUM>% (more preferably at least <NUM>%, more preferably at least <NUM>%, even more preferably at least <NUM>%, and possibly at least <NUM>%) of UV radiation in at least a substantial part of the range from <NUM> to <NUM> (or alternatively in a substantial part of the range from <NUM>-<NUM>).

The UV reflecting coating <NUM> is patterned (e.g., in the shape of a grid or in substantially parallel or non-parallel stripes) on the surface of substrate <NUM> as shown in <FIG>. The patterned shape of coating <NUM> may be formed as follows, for purposes of example. A pattern (not shown) is provided on the surface of substrate <NUM> prior to the coating <NUM> being formed, with the pattern being located in areas which are ultimately to be free of coating <NUM>. After the pattern is formed, a coating <NUM> is continuously formed across the entire or substantially the entire surface of substrate <NUM> over the pattern. The pattern can then be removed (along with the portions of coating <NUM> located directly over it) in order to create a patterned coating <NUM>, so that the coating <NUM> remains on only the portions of the substrate where the original pattern was not deposited. Thus, a patterned coating <NUM> can be formed in such a manner in example embodiments of this invention. The remaining patterned coating <NUM> is substantially invisible to human eyes, but is visible to bird eyes as explained above.

In certain example embodiments of this invention, the window unit (e.g., insulating glass (IG) window unit and/or laminated window unit) is designed to prevent or reduce bird collisions therewith. The IG window unit includes three substrates (e.g., glass substrates) spaced apart from one another, and at least one of the substrates supports an ultraviolet (UV) reflecting coating for reflecting UV radiation. The UV reflecting coating is a coating designed without any IR reflecting layer(s) of silver or gold. The UV reflecting coating <NUM> may be patterned by a laser (e.g., femto laser) which is used to either entirely or partially remove (e.g., via laser ablation) a portion of the coating in a pattern, so that after patterning by the laser the patterned coating is either not provided across the entirety of the window unit and/or is non-uniform in UV reflection across the window unit so that the UV reflection differs across different areas of the window thereby making the window unit more visible to birds which can see UV radiation and detect that pattern. Thus, in certain example embodiments, the as-deposited UV reflecting coating entirely remains on the substrate in areas not patterned by the laser, and partially remains in areas patterned by the laser. Femto lasers have been found to be advantageous in that they can efficiently pattern such UV reflecting coatings <NUM> without damaging the underlying glass substrate, and can more easily be used to remove only part of such a coating in patterned areas so as to maintain substantially the same surface energy in both patterned and non-patterned areas of the UV reflective coating. Surprisingly and unexpectedly, it has also been found that the user of the Femto lasers result in a final product with less haze that if a non-Femto laser has been used. In preferred example embodiments of this invention, the final coated article, including both patterned and nonpatterned areas, has a haze value of no greater than <NUM>, more preferably no greater than <NUM>, and most preferably no greater than <NUM>. Less haze is more aesthetically pleasing to humans, and by making the window more visible to birds, bird collisions and bird deaths can be reduced. Surprisingly, and unexpectedly, it has also been found that during patterning a laser fluence of from <NUM> to <NUM> J/cm<NUM>, and most preferably <NUM> to <NUM> J/cm<NUM>, advantageous results in a smoother ablation of the patterned areas and allows the ablation to occur with partial coating removal but without any significant damage to the glass substrate and without significant haze in the patterned areas. The patterned UV reflecting coating <NUM> is preferably substantially neutral in the visible range, so that the patterning of the UV coating is not reasonably seen by humans via the naked eye. Another advantage of laser is that we can do random patterning on the fly. In an example embodiment, not part of this invention, there is provided a method of making a window for reducing bird collisions, the window comprising a first glass substrate and a ultraviolet (UV) reflective coating supported by at least the first glass substrate, the method comprising: having the first glass substrate and the ultraviolet (UV) reflective coating supported by at least the first glass substrate; emitting a laser beam from at least one laser source, the laser beam comprising optical pulses with (i) a duration below <NUM> Femtoseconds and/or (ii) a fluence from <NUM> to <NUM> J/cm<NUM>; wherein the laser beam comprising optical pulses is incident upon the UV reflective coating and patterns the UV reflective coating into patterned and non-patterned areas which have different respective UV reflectances, the laser beam having been incident upon the patterned areas but not the non-patterned areas. The laser beam may comprise optical pulses with a duration below <NUM> Femtoseconds, and possibly a duration below <NUM> Femtoseconds. All layers of the UV reflective coating may be dielectric layers, or alternatively the UV reflective coating may be a low-E coating having at least one IR reflective layer sandwiched between at least first and second dielectric layers.

<FIG> demonstrate surprising technical advantages associated with the IG window units of <FIG> compared to that of <FIG>, and also demonstrate surprising technical advantages of the <FIG> embodiment (outboard laminated structure), according to this invention, compared to the <FIG> embodiment (inboard laminated structure), not part of this invention. <FIG> is a wavelength (nm) versus Transmission (T) % and Reflection (R) %, showing transmission and reflection as a function of wavelength (nm) for an example IG window unit of the <FIG> embodiment of this invention where the laminated glass substrates are on the outboard side (closest to the exterior of the building on which the window is to be provided) of the air gap, where broken lines are spectral curves in an area without the UV reflecting coating and solid lines are spectral curves in an area with the UV reflecting coating, and assuming for purposes of example <NUM> thick glass substrates, a <NUM> thick air gap, and about <NUM> thick PVB laminating film. In a similar manner, <FIG> is a wavelength (nm) versus Transmission (T) % and Reflection (R) %, showing transmission and reflection as a function of wavelength (nm) for an example IG window unit of the <FIG> embodiment where the laminated glass substrates are on the inboard side (closest to the interior of the building on which the window is to be provided) of the air gap, where broken lines are spectral curves in an area without the UV reflecting coating and solid lines are spectral curves in an area with the UV reflecting coating, and assuming for purposes of example <NUM> thick glass substrates, a <NUM> thick air gap, and about <NUM> thick PVB laminating film. For purposes of comparison, <FIG> is a wavelength (nm) versus Transmission (T) % and Reflection (R) %, showing transmission and reflection as a function of wavelength (nm) for an example IG window unit of prior art <FIG> having no laminated glass substrates, where broken lines are spectral curves in an area without the UV reflecting coating and solid lines are spectral curves in an area with the UV reflecting coating, and assuming for purposes of example <NUM> thick glass substrates, and a <NUM> thick air gap. The same low-E coating is assumed in each of <FIG>, and the same UV reflecting coating is assumed in each of <FIG>. Thus, <FIG> corresponds to an example of the <FIG> embodiment, <FIG> corresponds to an example of the <FIG> embodiment, and <FIG> corresponds to prior art <FIG>.

It can be seen that in <FIG> the solid transmission curve (Ta) remains flat in the UV region for much longer than in <FIG>. In particular, in <FIG> the transmission curve begins increasing around <NUM>, whereas in <FIG> the transmission curve does not begin increasing until after <NUM>, thereby demonstrating that the laminated structures in <FIG> suppress transmission in the UV region from <NUM>-<NUM> much better than does the prior art <FIG> structure that has no laminated structure. It is possible that this may be due to the presence of the laminating film <NUM> that absorbs UV radiation.

Thus, as shown in <FIG>, in the transmission mode, lamination (when laminating film <NUM> is present laminating together a pair of substrates) reduces UV transmission for both areas with and without UV reflecting coating, thereby enhancing the transmissive contrast ratio CR(TR), which is defined as the ratio of transmittance without UV coating to that with UV coating.

The contrast ratio has been found to be higher for the laminated IGUs of <FIG> around <NUM>-<NUM> (compared to <FIG>). The transmission curves for inboard laminated structure and outboard laminated structures are nearly identical, so the improvement is essentially the same in the transmission mode for the <FIG> and <FIG> embodiments.

On the other hand, the <FIG> IG unit with the outboard laminated structure has been found to realize improved performance features compared to both the <FIG> and <FIG> IG units. This is because <FIG> has a laminated structure (compared to <FIG>) and because <FIG> has the laminated structure on the outboard side of the air gap and low-E coating (compared to <FIG>). <FIG> illustrate that the IG units of <FIG> have very different reflection curves in UV spectra. In the case of outboard laminated structure of <FIG>, UV light from the sun is mostly absorbed by PVB <NUM> before it reaches the low-E coating <NUM>. But in the case of inboard laminated structure of <FIG>, a certain portion of UV light reaches and is reflected by the low-E coating <NUM>; this amount of extra UV reflection reduces the reflective contrast ratio CR(RF) which is defined as the ratio of reflectance in areas with UV coating <NUM> to areas without UV coating <NUM>.

Thus, due to providing the laminated structure on the outboard side of the air gap <NUM> and on the outboard side of the low-E coating <NUM>, the reflective contrast ratio of the IG unit has surprisingly been found to be significantly higher for the <FIG> embodiment of this invention, compared to the <FIG> embodiment, and thus the <FIG> IG window unit will be more visible to birds and thus realize less bird collisions than both <FIG> and the <FIG> embodiment.

<FIG> are cross sectional views of various UV reflecting coatings <NUM> that may be used on substrate <NUM> in the IG window unit of <FIG> or <FIG> in example embodiments of this invention. Glass substrate <NUM> may be soda-lime-silica based glass or any other suitable type of glass, and may be from about <NUM>-<NUM> thick, more preferably from about <NUM>-<NUM> thick, in example embodiments of this invention.

In the <FIG> embodiment, UV reflecting coating <NUM> includes high index transparent dielectric layers <NUM>, <NUM> and <NUM> of or including niobium oxide (e.g., Nb<NUM>O<NUM>, NbO<NUM> and/or NbO) and low index transparent dielectric layers <NUM> and <NUM> of or including silicon oxide (e.g., SiO<NUM> which may or may not be doped with aluminum and/or nitrogen). Note that layer <NUM> in <FIG> is optional and can be removed to improve UV reflectance in certain instances, or can instead be of or including zirconium oxide. In certain example embodiments, one or both of the silicon oxide layers <NUM> and/or <NUM> may be doped with other material such as from about <NUM>-<NUM>% aluminum and/or from about <NUM>-<NUM>% nitrogen. One or more of layers <NUM>, <NUM> and <NUM> may also be doped with other material in certain example instances. In the <FIG> embodiment, layer <NUM> is the outermost layer of the coating <NUM> and may be exposed to air. Each of layers <NUM>-<NUM> is considered "transparent" to visible light because each of these layers, standing alone, is substantially transparent to visible light (e.g., at least about <NUM>% transparent, more preferably at least about <NUM>% or <NUM>% transparent to visible light). High index transparent dielectric layers <NUM>, <NUM> and <NUM> of or including niobium oxide may have a refractive index (n) of from about <NUM> to <NUM>, more preferably from about <NUM> to <NUM>, and most preferably from about <NUM> to <NUM> (at <NUM>). In certain alternative embodiments, the niobium oxide may be replaced with titanium oxide (e.g., TiO<NUM>), zirconium oxide, hafnium oxide (e.g., HfO<NUM>), cerium oxide (e.g., CeO<NUM>), zinc sulfide, or bismuth oxide (e.g., Bi<NUM>O<NUM>) in one or more of high index layers <NUM>, <NUM> and/or <NUM>. Thus, in one such example, layer <NUM> may be of or including titanium oxide, while layers <NUM> and <NUM> are of or including niobium oxide, and layers <NUM> and <NUM> are of or including silicon oxide. Low index transparent dielectric layers <NUM> and <NUM> of or including silicon oxide may have a refractive index (n) of from about <NUM> to <NUM>, more preferably from about <NUM> to <NUM>, and most preferably from about <NUM> to <NUM> (all refractive index n values herein are measured at <NUM>). Transparent dielectric layers <NUM>-<NUM> are preferably deposited by sputtering in example embodiments of this invention. For example, transparent dielectric layers <NUM>, <NUM> and <NUM> of or including niobium oxide may be sputter deposited via at least one sputtering target of or including Nb, via sputtering in an atmosphere including a mixture of argon and reactive oxygen gases. And for example, transparent dielectric layers <NUM> and <NUM> of or including silicon oxide may be sputter deposited via at least one sputtering target of or including Si or SiAl, via sputtering in an atmosphere including a mixture of argon and reactive oxygen gases. Rotation C-Mag sputtering targets, or other types of targets, may be used. In sputtering operations, sufficient reactive oxygen gas may be used to achieve the refractive index values discussed herein. Ceramic targets may alternatively be used to sputter deposit one or more of these layers. While layers <NUM>-<NUM> are preferably deposited via sputtering, it is possible that they may be deposited via other techniques in alternative embodiments of this invention. While coating <NUM> consists of five layers in the <FIG> embodiment, it is possible that additional layers may be provided in alternative embodiments. For example, a protective layer of or including zirconium oxide (not shown) may be provided in the coating <NUM> as the uppermost layer over and directly contacting layer <NUM>. Coating <NUM> in the <FIG> embodiment and in other example embodiments contains no metallic reflective layer.

<FIG> is a cross sectional view of another UV reflecting coating <NUM> that may be used on substrate <NUM> in the <FIG> or <FIG> IG window unit. The <FIG> embodiment is the same as the <FIG> embodiment, except that transparent dielectric barrier layer <NUM> is provided between the glass substrate <NUM> and high index layer <NUM>. Note that layer <NUM> in <FIG> is optional and can be removed to improve UV reflectance in certain instances, or can instead be of or including zirconium oxide. The barrier layer <NUM> is of or including silicon nitride (e.g., Si<NUM>N<NUM>) in certain example embodiments of this invention. Barrier layer <NUM> may optionally be used in the coatings of any of <FIG>, but is only shown in <FIG> for purposes of simplicity. In certain example embodiments, silicon nitride based barrier layer <NUM> may be doped with other material such as from about <NUM>-<NUM>% aluminum and/or from about <NUM>-<NUM>% oxygen. The <FIG> embodiment is particular useful in heat treated (e.g., thermally tempered) embodiments, where the barrier layer <NUM> helps prevent or reduce migration of elements (e.g., Na) from the glass substrate into the coating during the high temperature heat treatment. Such heat treatment (e.g., thermal tempering) may include, for example heating the coated article in an oven or the like at temperature(s) of at least about <NUM> degrees C, more preferably of at least about <NUM> degrees C. The coating of the <FIG> embodiment may or may not be heat treated (e.g., thermally tempered) in example embodiments of this invention.

<FIG> is a cross sectional view of another UV reflecting coating <NUM> that may be used on substrate <NUM> in the <FIG> or <FIG> IG window unit. The <FIG> embodiment is the same as the <FIG> embodiment, except that layer <NUM> is removed. The coated article shown in <FIG> may have, for example, a film side UV reflectance of from about <NUM>-<NUM>%, with an example being about <NUM>% (reflecting at least this much UV radiation in at least a substantial part of the range from <NUM>-<NUM>). In an example of the <FIG> embodiment, layer <NUM> is the outermost layer of UV reflecting coating <NUM>, and layer <NUM> is of or including titanium oxide (e.g., TiO<NUM>), layer <NUM> is of or including silicon oxide (e.g., SiO<NUM> which may or may not be doped with aluminum and/or nitrogen), layer <NUM> is of or including niobium oxide (e.g., Nb<NUM>O<NUM>, NbO<NUM> and/or NbO), and layer <NUM> is of or including silicon oxide (e.g., SiO<NUM> which may or may not be doped with aluminum and/or nitrogen). Optionally, the coating of the <FIG> embodiment may also include an overcoat of or including zirconium oxide (e.g., ZrO<NUM>). In certain example embodiments of the <FIG> embodiment of this invention: (i) transparent dielectric layer <NUM> of or including titanium oxide may be from about <NUM>-<NUM> thick, more preferably from about <NUM>-<NUM> thick, even more preferably from about <NUM>-<NUM> thick, with an example thickness being from about <NUM>-<NUM>; (ii) transparent dielectric layer <NUM> of or including silicon oxide may be from about <NUM>-<NUM> thick, more preferably from about <NUM>-<NUM> thick, even more preferably from about <NUM>-<NUM> thick, with an example thickness being about <NUM>; (iii) transparent dielectric layer <NUM> of or including niobium oxide may be from about <NUM>-<NUM> thick, more preferably from about <NUM>-<NUM> thick, even more preferably from about <NUM>-<NUM> thick, with an example thickness being about <NUM> or about <NUM>; (iv) transparent dielectric layer <NUM> of or including silicon oxide may be from about <NUM>-<NUM> thick, more preferably from about <NUM>-<NUM> thick, even more preferably from about <NUM>-<NUM> thick, with example thickness being about <NUM> or about <NUM>; and (v) optional transparent overcoat protective dielectric layer <NUM> of or including zirconium oxide may be from about <NUM>-<NUM> thick, more preferably from about <NUM>-<NUM> thick, even more preferably from about <NUM>-<NUM> thick, with an example thickness being about <NUM>. To realize the desired UV reflectance and visible transmission values herein, niobium oxide based layer <NUM> is preferably substantially thicker than titanium oxide based layer <NUM>. For example, in certain example embodiments, niobium oxide based layer <NUM> is at least about <NUM> thicker (more preferably at least about <NUM> thicker, and most preferably at least about <NUM> thicker) than titanium oxide based layer <NUM>. Moreover, niobium oxide based layer <NUM> is also preferably thicker than each of layers <NUM> and <NUM>, for example layer <NUM> being at least about <NUM> thicker and most preferably at least about <NUM> thicker than each of silicon oxide based layers <NUM> and <NUM>. Silicon oxide based layer <NUM> is at least about <NUM> or <NUM> thicker than is silicon oxide based layer <NUM> in certain embodiments of the <FIG>, <FIG>, <FIG> embodiment of this invention. Optionally, a protective layer (not shown) of or including zirconium oxide may be provided as the outermost layer over layer <NUM> in the <FIG> coating (similar to the protective outer layer in <FIG>).

<FIG> is a cross sectional view of another UV reflecting coating <NUM> that may be used on substrate <NUM> in the <FIG> or <FIG> IG window unit. The coated article shown in <FIG> may have, for example, a film side UV reflectance of from about <NUM>-<NUM>%, with an example being about <NUM>% (reflecting at least this much UV radiation in at least a substantial part of the range from <NUM>-<NUM>). In an example of the <FIG> embodiment, layer <NUM> is of or including titanium oxide (e.g., TiO<NUM>), layers <NUM> and <NUM> are of or including silicon oxynitride (e.g., which may or may not be doped with aluminum), layer <NUM> is of or including titanium oxide (e.g., TiOz), and outermost protective layer <NUM> is of or including zirconium oxide (e.g., ZrO<NUM>). In certain example embodiments of the <FIG> embodiment of this invention: (i) transparent dielectric layer <NUM> of or including titanium oxide may be from about <NUM>-<NUM> thick, more preferably from about <NUM>-<NUM> thick, even more preferably from about <NUM>-<NUM> thick, with an example thickness being about <NUM>; (ii) transparent dielectric layer <NUM> of or including silicon oxynitride may be from about <NUM>-<NUM> thick, more preferably from about <NUM>-<NUM> thick, even more preferably from about <NUM>-<NUM> thick, with an example thickness being about <NUM>; (iii) transparent dielectric layer <NUM> of or including titanium oxide may be from about <NUM>-<NUM> thick, more preferably from about <NUM>-<NUM> thick, even more preferably from about <NUM>-<NUM> thick, with an example thickness being about <NUM>; (iv) transparent dielectric layer <NUM> of or including silicon oxynitride may be from about <NUM>-<NUM> thick, more preferably from about <NUM>-<NUM> thick, even more preferably from about <NUM>-<NUM> thick, with an example thickness being about <NUM>; and (v) transparent dielectric protective layer <NUM> of or including zirconium oxide may be from about <NUM>-<NUM> thick, more preferably from about <NUM>-<NUM> thick, with an example thickness being about <NUM> To realize the desired UV reflectance and visible transmission values herein, layer <NUM> is preferably substantially thicker than titanium oxide based layer <NUM>. For example, in certain example embodiments, titanium oxide based layer <NUM> is at least about <NUM> thicker (more preferably at least about <NUM> thicker, and most preferably at least about <NUM> thicker) than titanium oxide based layer <NUM>. And silicon oxynitride based layer <NUM> is at least about <NUM>, <NUM> or <NUM> thicker than is silicon oxynitride based layer <NUM> in certain embodiments of the <FIG>, <FIG>, <FIG> embodiment of this invention.

Claim 1:
An IG window unit comprising:
a first glass substrate (<NUM>);
a second glass substrate (<NUM>);
a third glass substrate (<NUM>);
wherein the first glass substrate (<NUM>) is provided at an exterior side of the IG window unit so as to face an exterior of a building in which the IG window unit is to be mounted;
wherein the second glass substrate (<NUM>) is provided between at least the first (<NUM>) and third (<NUM>) glass substrates;
wherein the third glass substrate (<NUM>) is provided at an interior side of the IG window unit so as to face an interior of a building in which the IG window unit is to be mounted;
a patterned UV reflecting coating (<NUM>) provided on the first glass substrate (<NUM>) and on an exterior surface of the IG window unit so as to face an exterior of a building in which the IG window unit is to be mounted;
wherein the first (<NUM>) and second (<NUM>) glass substrates are laminated to each other via a polymer inclusive laminating film (<NUM>);
a low-E coating (<NUM>) provided on a side of the second glass substrate (<NUM>) opposite the polymer inclusive laminating film (<NUM>), so that the second glass substrate (<NUM>) is located between the low-E coating (<NUM>) and the polymer inclusive laminating film (<NUM>);
wherein the first glass substrate (<NUM>) is located between the patterned UV reflecting coating (<NUM>) and the polymer inclusive laminating film (<NUM>);
wherein the UV reflecting coating (<NUM>) is not part of a low-E coating (<NUM>) and does not contain any IR reflecting layer of silver or gold; and
wherein the second glass substrate (<NUM>) is spaced apart from the third glass substrate (<NUM>) via at least an air gap, so that a laminated structure including the first glass substrate (<NUM>), the second glass substrate (<NUM>), and the polymer inclusive laminating film (<NUM>) is located on an outboard side of the air gap and on an outboard side of the low-E coating (<NUM>).