Automotive glazing with UV blocking properties

Abstract

A laminated glazing comprising an UV-control coating disposed on at least a portion of a glass layer is provided. Such UV-control coating has a transmittance of less than 10% at any spectral point when measured in a spectral range from 300 to 400 nm and a TTS no greater than 60%. The UV-control coating provides a filter for UV light in the glazing without the need of any further material within the stack. The UV-control coating also provides additional control for IR light. A roof and a sidelite having such glazing are also disclosed.

Description

AUTOMOTIVE GLAZING WITH UV BLOCKING PROPERTIESFIELD OF THE INVENTION

[0001] The present invention falls in the field of automotive glazing and relates to a glazing having ultraviolet control properties.BACKGROUND OF THE INVENTION

[0002] In the automotive industry, different materials are integrated into windows to reduce the effect of heat and radiation from the sun. Usually, a laminated safety glass includes multiple layers of materials that help control the incident radiation; for instance, glazing may require a solar control coating for blocking infrared (IR) radiation and a plastic interlayer to block the sunlight radiation properly. Typically, standard interlayers, such as a PVB with high ultraviolet (UV) control, provide a filter for UV light within the range from 300 to 365 nm having a transmittance of 0% within this range; nevertheless, if additional protection is required beyond 365 nm, special or specific interlayers need to be included in the glazing to achieve that protection. Unfortunately, this kind of configuration provides thicker stacks that may not be properly placed in the car's mounting having a thickness increase of at least 10% in the final product.

[0003] Additional protection from UV is required when sensitive films are included in the glazing. For instance, switchable films like SPD or LC need extra protection to avoid changes in properties after UV exposure. It has been reported that some of these films slowly discolor as they are exposed to UV light and become yellowish. Additionally, degradation of the dyes included in the switchable films is also a problem, causing undesirable color changes in the film, for example turning it into a full red LC film when exposed to UV light Breaking of constituents of an LC film, such as the LC monomer, can result in structural damages by losing short-range crystallinity of the LC or even losing dielectric anisotropy which would prevent the LC film from switching.

[0004] Therefore, it is desirable to integrate sunlight blockers, having extra UV-control properties that allow filtering such radiation not only to protect the passengers but also to protect components of the window that could be sensitive to damage when exposed to extended sunlight radiation, such as switchable films. In addition, there is a need for providing such control properties avoiding thepresence of any extra layer that could increase the thickness of the glazing.SUMMARY OF THE INVENTION

[0005] The present invention provides a solution for the above-mentioned drawbacks providing a glazing, particularly a sidelite and a roof that includes a UV thin-film coating disposed on the glazing to reduce exposure of the vehicle interior from the harmful effects of the ultraviolet component of sunlight.

[0006] In a first inventive aspect, the invention provides a glazing comprising a first glass layer having an outer major surface, surface one, and an inner major surface, surface two, wherein the outer major surface is opposite to the inner major surface; a second glass layer having an inner major surface, surface three, and an outer major surface, surface four, wherein the outer major surface is opposite to the inner major surface; at least one bonding layer arranged between the inner major surface of the first glass layer and the inner major surface of the second glass layer; a switchable film arranged between the inner major surface of the first glass layer and the inner major surface of the second glass layer; and an UV-control coating disposed on at least a portion of a major surface of the first glass layer, having a transmittance of less than 10% at any spectral point when measured in a spectral range from 300 to 400 nm and a total solar transmittance (TTS) no greater than 60%.

[0007] The UV-control coating disposed on the first glass layer provides a filter for UV light in the glazing without the need of using any further thick-film bonding material within the stack. Advantageously, the UV-control coating is designed to also provide additional control for near-IR light. The combination of high-index of refraction (IOR) layers together with low-index of refraction layers within the coating design allows to obtain the desired UV-control.

[0008] In a second inventive aspect, it is disclosed an automotive roof or sidelite window having the glazing with the deposited coating as mentioned previously.DESCRIPTION OF THE DRAWINGS

[0009] These and other features and advantages of the invention will be seen more clearly from the following detailed description of preferred embodiments provided only by way of illustrative and nonlimiting examples in reference to the attached drawings.

[0010] Figure 1 . This figure shows a cross section of a general embodiment of the invention.

[0011] Figure 2. This figure shows a cross section of an embodiment of the invention wherein PVB is used as bonding layer, and an SPD film is included.

[0012] Figure 3. This figure shows a cross section of an embodiment of the invention wherein LOCA is used as bonding layer, and an LC film is included.

[0013] Figure 4. This figure shows a cross section of an embodiment of the invention wherein LOCA is used as bonding layer, and edge seal and an LC film is included.

[0014] Figure 5. This figure illustrates the generic coating stack design according to an embodiment of the present invention.

[0015] Figure s. This figure illustrates the generic coating stack design according to another embodiment of the present invention.REFERENCE NUMBERS2.1 First glass layer2.2 Second glass layer201 Surface one, or outer major surface of the first glass layer202 Surface two, or inner major surface of the first glass layer203 Surface three, or outer major surface of the second glass layer204 Surface four, outer major surface of the second glass layer3 UV-control coating4, 4.1 , 4.2 Bonding layer6 Obscuration8 Additional coating22 Switchable film40 Edge sealDETAILED DESCRIPTION OF THE INVENTION

[0016] The present disclosure can be understood by reference to the detailed descriptions, drawings, examples, and claims, of this disclosure. It should be noted, however, that this disclosure is not limited to the specific compositions, articles, devices, and methods disclosed unless otherwise specified, as such can, of course, vary. It is also to be understood that the terminology used herein is for the purpose of describing aspects only and is not intended to be limiting the scope of the disclosure.

[0017] The following terminology is used along the whole document to describe features of the invention.

[0018] The term “layer”, as used in this context, shall include the common definition of the word, i.e.: a sheet, quantity, or thickness, of material, typically of some homogeneous substance.

[0019] Laminates, in general, are articles comprised of multiple layers of thin, relative to their length and width, material, with each thin layer having two oppositely disposed major faces, typically of uniform thickness, which are permanently bonded to one and other across at least one major face of each layer. The layers of a laminate may alternately be described as sheets or plies. Safety glass is glass that conforms to all applicable industry and government regulatory safety requirements for the application.

[0020] Typically, laminated automotive safety glass is made by bonding two glass layers, a first glass layer 2.1 and a second glass layer 2.2 together using a bonding layer 4 comprised of a sheet of transparent thermoplastic 4. The first glass layer 2.1 has an outer major surface 201 , surface one, and an inner major surface 202, surface two, wherein the outer major surface 201 is opposite to the inner major surface 202. The second glass layer 2.2 has an inner major surface 203, surface three, and an outer major surface 204, surface four, wherein the outer major surface 204 is opposite to the inner major surface 203. At least one bonding layer 4 is arranged between the inner major surface 202 of the first glass layer 2.1 and the inner major surface 203 of the second glass layer 2.2. An obscuration 6 may be also applied to the glass.

[0021] Figure 1 shows a cross section of an embodiment of a glazing 200 of the invention, wherein the glazing 200 comprises two glass layers 2.1 , 2.2, at least one bonding layer 4, a switchable film 22, a UV-control coating 3, an additional coating 8, and an obscuration 6.

[0022] In an embodiment of the invention, the types of glass that may be used include but are not limited to soda lime, aluminosilicate, lithium aluminosilicate, borosilicate and glass ceramics. In a preferred embodiment, the first and second glass layers 2.1 , 2.2 are soda lime glass layers.

[0023] In an embodiment, the thickness of the first 2.1 and second 2.2 glass layers may vary widely and thus be ideally adapted to the requirements of the individual cases. In another embodiment, the thickness of each glass layer of the glazing of the disclosure ranges from 0.3 mm to 5 mm, preferably such as between 0.5 mm and 4.0 mm or between 1 .5 mm and 3.8 mm, e.g. about 1.5 mm, 1.6 mm, 1.7 mm, 1.8 mm, 1.9 mm, 2.0 mm, 2.1 mm, 2,2 mm, 2.3 mm, 2.4 mm, 2.5 mm, 2.6 mm, 2.7 mm, 2.8 mm, 2.9 mm, 3.0 mm, 3.1 mm, 3.2 mm, 3.3 mm, 3.4 mm, 3.5 mm, 3.6 mm, 3.7 mm or 3.8 mm. Particular thickness for the first and second glass layers is 2.1 mm.

[0024] The bonding layer 4 has the primary function of bonding the major faces of adjacent layers to each other. The material selected is typically a thermoset plastic, but other plastics can be used. For automotive use, the most used bonding layer 4 is polyvinyl butyral (PVB). In addition to polyvinyl butyral, ethylene vinyl acetate (EVA), thermoplastic polyurethane (TPU), polyolefin elastomers (PoE), optical adhesive resins (OCR), optically clear adhesive (OCA), liquid optically clear adhesives (LOCA) or any combination thereof may be used.

[0025] LOCA is the acronym for Liquid Optically Clear Adhesive and refers to an adhesive material suitable for bonding substrates in contact with it. LOCAs have high optical performance measured in terms of light transmission and low haze. Before bonding, LOCA is initially in a liquid state which allows it to flow and adapt to different shapes having variable thicknesses. Then, to become rigid LOCAs usually undergo a chemical / physical process (curing reaction) that polymerizes the liquid into a rubber-like texture. When needed, LOCAs properties can be modified by using additives and / or stabilizers. In the context of this invention, when a LOCA is mentioned, it refers to its rigid configuration as a rubber and / or thermoset material unless mentioned otherwise.

[0026] In an embodiment, the curing mechanism for the LOCA is selected from the group comprising thermal curing e.g., heat, light exposure e.g., UV light, humidity, chemical reaction and a combination thereof. In yet another embodiment, the LOCA is selected from the group comprising polyurethane (PU), silicones, acrylics, epoxides and a combination thereof.

[0027] In an embodiment, an edge seal 40 is arranged between the inner major surface 202 of the first glass layer 2.1 and the inner major surface 203 of the second glass layer 2.2. The edge seal is selected from the group comprising polyisobutylene (RIB), silicones, acrylics, and PU based adhesives.

[0028] In different embodiments, the glass laminate of the present invention may include additional interlayers, such as interlayers designed to dampen sound and with tinted colors. In the context of this invention, additional interlayers are arranged between the first and second glass layers of the laminate, but do not necessarily act as a bonding interlayer. In an embodiment, when dampen sound interlayers are included, they are comprised whole or in part of a layer of plastic that is softer and more flexible than that normally used. Additional embodiments of the present invention include a plastic interlayer with tinted colors, such as grey or brown plastic interlayers, such as PVB, to manage the color of the full product. Additional embodiments could have both functions, sound control and tinted.

[0029] In one embodiment, the thickness of the bonding layer 4 ranges from 0.3 mm to 2.0 mm, particularly from 0.5 mm to 1.5 mm. In another embodiment, the bonding layer 4 has a thickness of, of about of at most or at most about 0.5 mm, 0.6 mm, 0.7 mm, 0.8 mm, 0.9 mm, 1.0 mm, 1.1 mm, 1.2 mm, 1.3 mm 1.4 mm and 1.5 mm. Particular thicknesses for the bonding layer 4 are for instance 0.38 mm, 0.631 mm, 0.76 mm and 0.81 mm. In another embodiment, when a dampen sound bonding layer is included, the bonding layer thickness ranges from 0.51 mm to 0.85 mm, particular thicknesses are for instance 0,51 mm, 0.76 mm and 0.81 mm.

[0030] The glazing includes a switchable film 22 arranged between the inner major surface 202 of the first glass layer 2.1 and the inner major surface 203 of the second glass layer 2.2. In the context of this disclosure a switchable film should be understood as a film that responds to external stimuliby changing optical, electrical and / or mechanical properties, thus providing dynamic control over light transmission.

[0031] The glazing of the disclosure includes a UV-control coating 3 disposed on at least a portion of surface two 202 of the first glass layer 2.1 . The UV-control thin-film coating provides a filter for UV light in the glazing without the need of using any further UV-control material. In an embodiment, the coating provides an additional function being an IR reflector. In an embodiment, the coating provides blocking properties for UV light within 300 to 400 nm, preferably the coating has a light transmittance of less than 10% between the 400 nm to 410 nm.

[0032] In an embodiment of the invention, the UV-control coating 3 has a multilayer configuration. Preferably, the UV-control coating has a light transmittance of less than 10% when measured in a spectral range from 300 to 400 nm and a TTS of no greater than 60%. In a preferred embodiment, the UV-control coating 3 has a transmittance of less than 7%, preferably less than 4% when measured in a spectral range from 300 to 400 nm and a TTS of no greater than 55%

[0033] The glass layers may have additional coatings applied on them by Magnetron Sputtered Vacuum Deposition (MSVD) as well as other methods known in the art, such as pyrolytic, spray, chemical vapor deposition (CVD), dip, sol-gel, etc. One or more coatings can be used on the second glass layer 2.2, particularly on the exterior surface 204. These additional coating or coatings 8 include but are not limited to low emissivity (low-E), anti-reflective, anti-fingerprint, or any combination thereof.

[0034] Low-E coating adds thermal insulation properties to a glazing by reducing its emissivity (the heat energy in mid-infrared range), especially when is used in conjunction with a solar-control coating, which blocks a significant portion of direct solar energy in the near-IR spectral region. This combination has proved especially useful in panoramic glass roofs.

[0035] Anti-reflective coatings have seen increased use in automotive glazing applications considering that the interior reflection may be distracting with all of the light-emitting gizmos mounted in the instrument panel and other parts of the cabin.

[0036] An anti-fingerprint coating is desirable since fingerprints on the glass are more noticeablewith the decoupled light backlighting them. In preferred embodiments, coatings that combine two or more of the mentioned functionalities are included in the invention.

[0037] Obscurations 6 are commonly used on glazing, to hide the mounting adhesive and other features, and may be a black enamel frit printed or an insert made of a painted or an opaque plastic material. When included the obscuration is printed on surface two 202 of the first glass layer 2.1 , and / or surface three 203 of the second glass layer 2.2 and / or surface four 204 of the second glass layer 2.2. Obscurations can be printed on top of other coatings, such as the UV-control coating. The obscuration needs to be opaque in the sense of difficulty to see through rather than blocking all light. The typical light transmission is less than 5%, preferably less than 3% and more preferably equal to 0%.

[0038] In the context of this invention, a switchable film 22 should be understood as a film that responds to external stimuli by changing optical, electrical and / or mechanical properties, thus providing dynamic control over light transmission, having at least two states, a darker state and a lighter state.

[0039] The switchable films 22 that can be employed in the context of this disclosure include but are not limited to, Suspended Particle Devices (SPD), Polymer Dispersed Liquid Crystal (PDLC), Polymer Network Liquid Crystal (PNLC), electrochromic (EC) films and Liquid Crystal (LC) films.

[0040] SPD goes from dark in the off state to less dark in the on state. In an SPD film, microscopic droplets of liquid containing needle like particles, light valves, are suspended in a matrix. In the off state the particles are in a random state of alignment and block the transmission of light. The degree of alignment and resulting tint can be varied in response to the applied AC voltage. The light transmittance in the on and off states can also be shifted through changes to the thickness and composition of the active material. In the off state, it is still possible to see clearly through SPD.

[0041] PDLC is a switchable light scattering technology which goes from opaque in the off state to clear in the on state. In a PDLC film, microscopic droplets of liquid crystal are suspended in a polymer matrix. In the off state the liquid crystals are in a random state of alignment and scatter the light providing privacy. In the off state, the film is substantially opaque. When an electric field is applied,the crystals align and allow light to pass. The degree of scattering can be varied by varying the amplitude of the applied voltage.

[0042] PNLC is very similar to PDLC except that the internal polymeric structure is an interconnected network instead of droplet suspension.

[0043] LC is a glass or plastic cell containing liquid crystal and dyes that changes transmission when an electrical field is applied to the system. LC switchable films comprise two plastic or glass substrates containing at least a liquid crystal material, a set of spacers to guarantee a constant distance between the two substrates, and a perimetral seal between the two substrates that contain the liquid crystal material inside of the film. The liquid crystal changes its molecules orientation when an electrical field is applied. The liquid crystal orientation together with either a dichroic dye or a set of polarizers will generate a change of light transmission under the influence of an electric field versus no electric field.

[0044] Electrochromic switchable films comprise layers of a material that change from dark to clear when a low direct current volage is applied to the electrodes. Reversing the electrical field polarity changes the system from clear back to dark.

[0045] In a preferred embodiment of the invention as depicted in Fig. 2 the glazing comprises the first glass layer 2.1 , the UV-control coating 3 disposed on the inner major surface 202 of the first glass layer 2.1 , an SPD switchable film 22 sandwiched between two PVB bonding layers 4.1 , 4.2, and the second glass layer 2.2.

[0046] In another preferred embodiment as depicted in Fig. 3 the glazing comprises the first glass layer 2.1 , the UV-control coating 3 disposed on the inner major surface 202 of the first glass layer 2.1 , an LC switchable film 22 embedded into a LOCA layer 4, between the first 2.1 and the second glass layer 2.2.

[0047] In another preferred embodiment as depicted in Fig. 4 the glazing comprises the first glass layer 2.1 , the UV-control coating 3 disposed on the inner major surface 202 of the first glass layer 2.1 , an LC switchable film 22 embedded into a LOCA layer 4, between the first 2.1 and the second glass layer 2.2, and an edge seal 40 in the edge of the glazing (perimeter).

[0048] In a preferred embodiment, the TTS of the laminated glazing of the disclosure in the lighter state is more than 30%, preferably more than 40%. In another embodiment, the TTS of the laminated glazing of the disclosure in the darker state is less than 40%, preferably less than 30%.

[0049] The generic design for Ag-inclusive solar-control stack for blocking IR waves typically includes at least a bottom layer deposited on the glass which includes sodium blocking properties, to prevent Na atoms from diffusing in the stack of glass. A wetting layer under the Ag layer controls the crystalline properties of the silver, a blocking layer on top of the Ag layer prevents damage during deposition, and a capping layer provides good durability and oxygen barrier properties to ensure good encapsulation during post-deposition heat treatment before the glass with coating goes though lamination. It should be noted that solar-control coatings may comprise more than one Ag-inclusive functional layer.

[0050] In the present invention, the design of the coating stack 3 has been carefully optimized to provide UV-control properties along with a low total solar transmittance. The combination of highland low-IOR layers within the coating design allows to obtain the desired UV-control. In an embodiment, the UV-control coating also provides IR control. In an embodiment, the glazing of the disclosure does not include any additional interlayer and / or bonding layer having a transmittance of less than 10%, more preferably of less than 5%, between 400 nm and 410 nm, such as a PVB with low transmittance.

[0051] In an embodiment of the invention, the UV-control coating 3, having additional IR control, has a multilayer configuration, the layers are listed in the order that they are deposited on the glass as depicted in Fig 5:• a sodium diffusion barrier layer 301 disposed on the inner major surface 202 of the first glass layer 2.1 ;• a foundation layer 302 disposed on top of the sodium diffusion barrier layer 301 ;• a silver-inclusive functional multilayer 303 disposed on top of the foundation layer 302;• a color-tuning layer 304 disposed on top of the silver- inclusive functional multilayer 303; a first high-index layer 305 disposed on top of the color tuning layer 304;a first low-index layer disposed 306 on top of first high-index layer 305;• a second high-index layer 307 disposed on top of the first low-index layer 306;• a second low-index layer 308 disposed on top of the second high-index layer 307; and• a third high-index layer 309 disposed on top of the second low-index layer 308.

[0052] In another embodiment of the invention, an optional fourth high-index layer 310 is disposed between the silver- inclusive functional multilayer 303 and the color tuning layer 304.

[0053] In another embodiment of the invention, an additional silver-inclusive functional multilayer is included in the stack between the color-tuning layer 304 and the first high-index layer 305 having the following layer configuration as depicted in Fig. 6:• a sodium diffusion barrier layer 301 disposed on the inner major surface 202 of the first glass layer 2.1 ;• a foundation layer 302 disposed on top of the sodium diffusion barrier layer 301 ;• a first silver- inclusive functional multilayer 303.1 disposed on top of the foundation layer 302;• a color-tuning layer 304 disposed on top of the silver- inclusive functional multilayer 303;• a second silver- inclusive functional multilayer 303.2 disposed on top of the color-tuning layer 304;• a first high-index layer 305 disposed on top of the second silver- inclusive functional multilayer 303.2;• a first low-index layer disposed (306) on top of first high-index layer 305;• a second high-index layer 307 disposed on top of the first low-index layer 306;• a second low-index layer 308 disposed on top of the second high-index layer 307; and• a third high-index layer 309 disposed on top of the second low-index layer 308.

[0054] Each silver-inclusive functional multilayer 303 comprises a wetting layer 331 , a silver layer 332, a blocker layer 333 and a capping layer 334 as depicted in Fig. 4.

[0055] The sodium diffusion barrier layer 301 is selected from the group comprising SiOx, SiOxNy and SiNx and has a thickness ranging from 10 to 80 nm, more preferably from 10 to 50 nm.

[0056] The foundation layer 302 and the first, second, third and fourth high index layers 305, 307, 309 and 310 respectively have an IOR higher than 2.2 and are selected from the group comprising TiOx, NbOx, ZrOx and TiSrOx. The foundation layer 302 has a thickness ranging from 5 to 40 nm, more preferably from 20 to 50 nm. The first, second, third and fourth high index layers 305, 307, 309 and 310 respectively have a thickness ranging from 10 to 120 nm, and more preferably from 20 to 110 nm.

[0057] The wetting layer 331 , the capping layer 334 and the color-tuning layer 304 are selected from the group comprising ZnSnOx, ZnAIOx, ZnBOx, SiOxNy, SiNx, CrOxSi, AITiOx, and ZrSiOx, and the wetting layer 331 has a thickness ranging from 5 to 30 nm, more preferably from 15 to 25 nm; and the capping layer 334 has a thickness ranging from 5 to 45 nm, more preferably from 10 to 40 nm; and the color-tuning layer 304 has a thickness ranging from 20 to 80 nm, and more preferably from 35 to 75 nm.

[0058] The low-index layers 306 and 308 have an IOR lower than 1.8 and are selected from the group comprising SiOx, SiOxNy, AIOx, TiAIOx, and have a thickness ranging from 10 to 120 nm, and more preferably from 10 to 70 nm.

[0059] The silver layer 332 is selected from the group comprising Ag and an Ag alloy and has a thickness ranging from 6 to 20 nm; and more preferably from 10 to 12 nm.

[0060] The blocker layer 333 is selected from the group comprising metals or metal-based compounds such as NiCr, NiCrOx, Ti, and has a thickness ranging from 1 to 5 nm, and more preferably from 1 to 2 nm.

[0061] Examples.

[0062] Example 1.

[0063] Example one relates to a sidelite laminate for a vehicle including the following configuration: the sidelite laminate has a a length of 550 mm and a width of 450 mm. The first glass layer 2.1 and second glass layer 2.2 are comprised of a clear soda-lime glass composition with a thickness of 2.1 mm. The UV- and IR-control coating 3 is deposited on the inner surface 202 of the first glass layer2.1 . A black obscuration 6 is printed on the inner surface 202 of the first glass layer 2.1 prior to theapplication of the UV- and-IR-control coating 3. A black obscuration 6 is also printed on the outer surface 204 of the second glass layer 2.2. A silicon based LOCA is used as a bonding layer 4 having a thickness of 1.5 mm. Additionally, a LC switchable film 22 is embedded within the LOCA layer having a thickness of 0.38 mm.

[0064] The layer sequence of the UV- and IR-control coating 3 deposited on the inner surface 202 of the first glass layer 2.1 is as follows:Sodalime glass 2.1 2.1 mmSiOx 10.3 nmTiOx 29.5 nmZnAIOx 21.4 nmAg 10.1 nmNiCr 1.1 nmZnAIOx 14.1 nmTiOx 42.1 nmZnSnOx 33.2 nmTiOx 33.8. nmSiOx 45.5 nmTiOx 39.8 nmSiOx 41.0 nmTiOx 20.6 nm

[0065] The transmittance of the monolithic outer glass with UV-control coating is 4.3% measured at 400 nm and the transmittance of the glazing at 400 nm could be the same or lower. Additionally, the TTS from the glazing is 42% for the lighter state and 32% for the darker state.

[0066] Example 2.

[0067] Example two is similar to example one but the layer sequence of the UV and IR-control coating (3) deposited on the inner surface 202 of the first glass layer 2.1 includes an additional silver functional multilayer as follows:Sodalime glass 2.1 2.1 mmSiOx 49.0 nmTiOx 14.5 nmZnAIOx 15.0 nmAg 10.0 nmNiCr 1.1 nmZnAIOx 38.7 nmZnSnOx 39.4 nmZnAIOx 5.7 nmAg 11.1 nmNiCr 1.2 nmZnAIOx 6.4 nmTiOx 96.0 nmSiOx 10.6 nmTiOx 30.0 nmSiOx 29.7 nmTiOx 108.0 nm

[0068] The transmittance of the monolithic outer glass with UV-control coating is 8.2% measured at 400 nm and the transmittance of the glazing at 400nm could be the same or lower. Additionally, the TTS from the glazing is 32% for the lighter state and 25% for the darker state.

[0069] Example 3

[0070] Example three is similar to example one further including an acoustic PVB layer having a thickness of 0.51 mm placed between the first glass layer 2.1 and the LOCA bonding layer 4.

[0071] The transmittance of the monolithic outer glass with UV-control coating is 4.3% measured at 400 nm and the transmittance of the glazing at 400 nm could be the same or lower. Additionally, the TTS from the glazing is 42% for the lighter state and 32% for the darker state.

[0072] Example 4

[0073] Example four is similar to example two further including an acoustic PVB layer having a thickness of 0.51 mm placed between the first glass layer 2.1 and the LOCA bonding layer 4.

[0074] The transmittance of the monolithic outer glass with UV-control coating is 8.2% measured at 400 nm and the transmittance of the glazing at 400 nm could be the same or lower. Additionally, the TTS from the glazing is 32% for the lighter state and 25% for the darker state.

[0075] Example 5

[0076] Example five is similar to example one except for the bonding layer and switchable film. Instead of LOCA, an acoustic PVB having a thickness of 0.76 mm and a grey PVB having a thickness of 0.38 mm are used as bonding layers 4.1 , and 4.2. Alternatively, an SPD instead of a LC switchable film 22 is embedded within the bonding layers 4.1 and 4.2, the film 22 having a thickness of 0.38 mm.

[0077] The transmittance of the monolithic outer glass with UV-control coating is 4.3% measured at 400 nm and the transmittance of the glazing at 400 nm could be the same or lower. Additionally, the TTS from the glazing is 47% for the lighter state and 31% for the darker state.

[0078] Example 6

[0079] Example six is similar to example two, except for the bonding layer and switchable film. Instead of a LOCA, an acoustic PVB having a thickness of 0.51 mm and a grey PVB having a thickness of 0.38 mm are used as a bonding layer 4.1 , 4.2. Alternatively, an SPD, instead of a LC switchable film 22 is embedded within the bonding layers 4.1 and 4.2, the film having a thickness of 0.4 mm.

[0080] The transmittance of the monolithic outer glass with UV-control coating is 8.2% measured at 400 nm and the transmittance of the glazing at 400 nm could be the same or lower. Additionally, the TTS from the glazing is 33% for the lighter state and 23% for the darker state.

[0081] Example 7

[0082] Example seven is similar to example one, but instead of sidelite laminate, the glazing is a large panoramic roof laminate having a length of 1400 mm and a width of 1100 mm.

[0083] Example 8

[0084] Example eight is similar to example one, but the glazing additional includes an edge seal 40 in the glass edge of the glazing.

Claims

CLAIMSWhat is claimed is:1 . A glazing (1), comprising: a first glass layer (2.1) having an outer major surface (201), surface one, and an inner major surface (202), surface two, wherein the outer major surface (201) is opposite to the inner major surface (202); a second glass layer (2.2) having an inner major surface (203), surface three, and an outer major surface (204), surface four, wherein the outer major surface (204) is opposite to the inner major surface (203); at least one bonding layer (4) arranged between the inner major surface (202) of the first glass layer (2.1) and the inner major surface (203) of the second glass layer (2.2); a switchable film (22) arranged between the inner major surface (202) of the first glass layer (2.1) and the inner major surface (203) of the second glass layer (2.2); and an UV-control coating (3) disposed on at least a portion of a major surface (201 , 202) of the first glass layer (2.1), having a transmittance of less than 10% at any spectral point when measured in a spectral range from 300 to 400 nm and a TTS no greater than 60%.

2. The glazing according to claim 1 , wherein the UV-control coating (3) has a transmittance of less than 7%, preferably less than 4% when measured in a spectral range from 300 to 400 nm and a TTS no greater than 55%.

3. The glazing according to claim 1 to 2, wherein the at least one bonding layer is selected from the group comprising polyvinyl butyral (PVB), ethylene vinyl acetate (EVA), thermoplastic polyurethane (TPU), polyolefin elastomers (PoE), optical adhesive resins (OCR), liquid optical clear adhesive resins (LOCA) and a combination thereof.

4. The glazing according to claim 1 to 3, wherein the first glass layer (2.1) and the second glass layer (2.2) are selected from the group comprising aluminosilicate, soda lime, and borosilicate glass.

5. The glazing according to claim 1 to 4, further comprising an additional coating (8) selected from the group comprising an anti-reflective coating, a Low-E, an anti-fingerprint, a color control coating and combinations thereof and is disposed in the outer major surface (204) of the second glass layer (2.2).

6. The glazing according to claim 1 to 5, wherein the switchable film (22) is selected from the group comprising suspended particle device (SPD), polymer dispensed liquid crystal (PDLC), polymer Network Liquid Crystal (PNLC), liquid crystal (LC) and electrochromic (EC).

7. The glazing according to claim 6, wherein the glazing comprises the following structure: the first glass layer (2.1); the UV-control coating (3) disposed on the inner major surface (202) of the first glass layer (2.1); an SPD switchable film (22) sandwiched between at least two PVB bonding layers (4.1 , 4.2); and the second glass layer (2.2).

8. The glazing according to claim 6, wherein the glazing comprises the following structure: the first glass layer (2.1); the UV-control coating (3) disposed on the inner major surface (202) of the first glass layer (2.1); an LC switchable film (22) sandwiched between at least two LOCA bonding layers (4.1 , 4.2); and the second glass layer (2.2).

9. The glazing according to any of the preceding claims, wherein the UV-control coating (3) also provides IR control.

10. The glazing according to claim 9, wherein the UV and IR-control coating (3) has a multilayer structure comprising:a sodium diffusion barrier layer (301) disposed on the inner major surface (202) of the first glass layer (2.1); a foundation layer (302) disposed on top of the sodium diffusion barrier layer (302); a silver- inclusive functional multilayer (303) disposed on top of the foundation layer (302); a color tuning layer (304) disposed on top of the silver- inclusive functional multilayer (303); a first high-index layer (305) disposed on top of the color tuning layer (304); a first low-index layer disposed (306) on top of first high-index layer (305); a second high-index layer (307) disposed on top of the first low-index layer (306); a second low-index layer (308) disposed on top of the second high-index layer (307); a third high-index layer (309) disposed on top of the second low-index layer (308); and an optional fourth high-index layer (310) disposed between the silver- inclusive functional multilayer (303) and the color tuning layer (304).

11. The glazing according to claim 10, wherein the silver- inclusive functional multilayer (303) comprises a wetting layer (331), a silver layer (332), a blocker layer (333) and a capping layer (334).

12. The glazing according to claim 10 to 11 , wherein the sodium diffusion barrier layer (301) is selected from the group comprising SiOx, SiOxNy and SiNxand has a thickness ranging from 10 to 80 nm, more preferably from 10 to 50 nm.

13. The glazing according to claim 10 to 12, wherein the foundation layer (302) and the first, second, third and fourth high index layers ( 305, 307, 309, 310) having an IOR higher than 2.2 areselected from the group comprising TiOx, NbOx, ZrOx and TiSrOx, and the foundation layer (302) has a thickness ranging from 5 to 40 nm, more preferably from 20 to 50 nm and the first, second and third high index layers ( 305, 307, 309) have a thickness ranging from 10 to 120 nm, more preferably from 20 to 110 nm.

14. The glazing according to claim 10 to 13, wherein the wetting layer (331) and the capping layer (334) and the color tuning layer (304) are selected from the group comprising ZnSnOx, ZnAIOx, ZnBOx, SiOxNy, SiNx, CrOxSi, AITiOx, and ZrSiOx, and the wetting layer 331 has a thickness ranging from 5 to 30 nm, more preferably from 15 to 25 nm; and the capping layer 334 has a thickness ranging from 5 to 45 nm, more preferably from 10 to 40 nm; and the color-tuning layer 304 has a thickness ranging from 20 to 80 nm, and more preferably from 35 to 75 nm.

15. The glazing according to claim 10 to 14, wherein the low index layers (306, 308) having an IOR lower than 1 .8 are selected from the group comprising SiOx, SiOxNy, AIOx, TiAIOx, and have a thickness ranging from 10 to 120 nm, more preferably from 10 to 70 nm.

16. The glazing according to claim 10 to 15, wherein the silver layer (332) is selected from the group comprising Ag and an Ag alloy and has a thickness ranging from 6 to 20 nm; more preferably from 10 to 12 nm.

17. The glazing according to claim 10 to 16, wherein the blocker layer (33) is selected from the group comprising metals or metal-based compounds such as NiCr, NiCrOx, Ti, and has a thickness ranging from 1 to 5 nm, more preferably from 1 to 2 nm.

18. The glazing according to claim 10 to 17, further comprising an additional silver- inclusive functional multilayer.

19. The glazing according to claim 18, wherein the glazing does not include an additional interlayer and / or bonding layer having a light transmittance of less than 10% between 400 nm and 410 nm.

20. An automotive roof or sidelite window comprising a glazing according to any of the preceding claims.

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