Laminated glass with improved sensor compatibility

Abstract

Disclosed is a multilayer panel comprising a first rigid substrate, a polymer interlayer, and a second rigid substrate, the multilayer panel having sensor areas for at least a first sensor and a second sensor, the first polymer interlayer having a solar absorption capability with a first visible light transmittance, the first sensor area including a second polymer interlayer selected to provide a first optically transparent area in the first sensor area, the first optically transparent area having a second light transmittance selected to allow the first sensor to operate, the second sensor area including a third polymer interlayer selected to provide a second optically transparent area in the second sensor area, the second optically transparent area having a third light transmittance selected to allow the second sensor to operate, and the first polymer interlayer, second polymer interlayer, and third polymer interlayer are different.

Description

[Technical Field]

[0001] The present disclosure relates to the field of polymer interlayers for multiple layer glass panels and multiple layer glass panels having at least one polymer interlayer sheet. Specifically, the present disclosure relates to the field of multiple layer panels having one or more sensors, including a polymer interlayer, where the multiple layer panel has improved sensor compatibility. [Background technology]

[0002] Multilayer panels generally comprise one or more polymer interlayers sandwiched between two substrates (such as, but not limited to, glass, polyester, polyacrylate, or polycarbonate). Laminated multilayer glass panels are commonly used in architectural window applications, as well as in automobile and aircraft windows and photovoltaic panels. The first two applications are commonly referred to as laminated safety glass. The primary function of the interlayer in laminated safety glass is to absorb energy resulting from impact or force applied to the glass, to keep the glass layers together even when force is applied and the glass breaks, and to prevent the glass from breaking into sharp shards. Additionally, the interlayer may impart a much higher sound insulation rating to the glass, reduce UV and / or IR light transmittance, and enhance the aesthetic appeal of the associated window. In photovoltaic applications, the primary function of the interlayer is to encapsulate the photovoltaic panels used to generate and supply electricity in commercial and residential applications.

[0003] It has become common to utilize multilayer or multi-layer interlayers to achieve specific properties and performance characteristics of glass panels. As used herein, the terms "multilayer" and "multilayer" refer to an interlayer having two or more layers, and multilayer and multilayer may be used interchangeably. Multilayer interlayers typically include at least one flexible layer and at least one rigid layer. Interlayers having a soft "core" layer sandwiched between two stiffer or harder "skin" layers are designed with sound-insulating properties for glass panels. Interlayers with the reverse configuration, i.e., having a rigid layer sandwiched between two flexible layers, have been found to improve the impact performance of glass panels and can also be designed for sound insulation. Examples of multilayer interlayers may also include at least one "clear" or non-tinted layer, at least one tinted layer, or at least one conventional layer, such as a non-acoustic-absorbing layer, and at least one acoustic-absorbing layer (i.e., a layer having acoustic properties or the ability to provide sound insulation or reduce sound transmission, as further defined below). Other examples of multi-layer interlayers include interlayers having at least two layers of different colors for aesthetic appeal. Colored layers typically contain pigments or dyes, or some combination of pigments and dyes.

[0004] Interlayer layers are generally manufactured by mixing a polymeric resin, such as poly(vinyl butyral), with one or more plasticizers and melt processing the mixture into a sheet by any applicable process or method known to those skilled in the art, including, but not limited to, extrusion. Multi-layer interlayers can be manufactured by processes such as coextrusion or lamination that combine the layers together to form a unitary structure. Other additional components may optionally be added for various other purposes. After the interlayer sheet is formed, it is typically collected and rolled for transportation and storage, and for subsequent use in multiple layer glazing panels, as described below.

[0005] The following briefly describes how multilayer glass panels are typically manufactured with these interlayers. First, at least one polymer interlayer sheet (single or multi-layer) is placed between two substrates, and excess interlayer is trimmed from the edges to create an assembly. It is not uncommon to place multiple polymer interlayer sheets, or a polymer interlayer sheet with multiple layers (or a combination of both) between two substrates to create a multilayer glass panel with multiple polymer interlayers. Next, air is removed from the assembly by any applicable process or method known to those skilled in the art. For example, by nip rollers, vacuum bags, or another degassing mechanism. The interlayer is then partially pressed onto the substrates by any method known to those skilled in the art. In a final step, this pre-bond is made more permanent by a high-temperature, high-pressure lamination process or any other method known to those skilled in the art, such as, but not limited to, an autoclave, to form the final integrated structure.

[0006] Multi-layer interlayers are commercially available, such as tri-layer interlayers with a soft core layer and two hard surface layers, optionally with additional functionality such as solar absorption, coloring, and other options. The hard surface layers provide handling, processing, and mechanical strength for the interlayer. The soft core layer provides acoustic damping properties.

[0007] As windshield functionality improves, more sensors are required to provide this functionality. Modern vehicles, which have laminated glass (such as a windshield) containing two glass panes and a polymer interlayer, often have multiple sensors, including optical sensors, lane departure cameras, LIDAR, and rain sensors. Rain sensors are one of the most common types of sensors operating in the infrared spectrum. LIDAR, developed primarily for autonomous driving applications, is a relatively new type of sensor operating in the infrared spectrum. Adaptive driver assistance systems (also known as ADAS) present designers with a multitude of lighting management challenges. ADAS may include a variety of passive and active sensors and cameras, all of which must function based on light passing through and / or reflecting off the laminate (such as a windshield). Each ADAS component operates within a unique wavelength or wavelength range within the EMI spectrum. The functional range may be within either the UV, visible, and / or near-infrared (NIR) regions. ADAS can also function in conjunction with a head-up display (HUD) system within the vehicle.

[0008] The sensor area often has a different polymer material. This may be referred to as a "cutout" or "patch." While some windshields may have the same material in the sensor(s) area, in some cases, such as when different levels of visible or infrared light transmittance are required in the sensor area, it is necessary to have different materials. For example, a windshield may have a high solar absorber loading to provide the windshield with a certain level of solar absorption capacity, but the light transmittance level from the high solar absorbing material may be too low for the sensor(s) to function properly. In some cases, when the laminated glass is first manufactured, the transmittance level may be above the minimum required for the sensor to function, allowing the sensor to function properly. However, over time, solar absorbing materials, such as solar absorbing interlayers containing solar absorbers such as cesium tungsten oxide, tend to darken over time (sometimes referred to as photodarkening or photochromic darkening), substantially reducing light transmittance and potentially causing the sensor to function improperly due to low visible light transmittance. Some applications, such as vehicles requiring high levels of heat absorption and / or reflection, require very high solar loads. This is especially important in vehicles with large windows, sunroofs, etc., as well as electric vehicles. Therefore, a different material that does not darken over time may be required to allow the sensor to function.

[0009] Some windshields have two or more sensors. Each sensor may require different characteristics, such as a level of light transmittance. For example, a windshield having a sensor, such as a light detection and ranging (LIDAR) sensor, may require high optical transparency and light transmittance, so a polymer interlayer capable of allowing high levels of light (greater than 90% at a particular wavelength) to pass through the glass may be desirable. Other sensors that may be located in the same general area of ​​the windshield may have different requirements. For example, there may be a rain sensor to determine whether to activate the windshield wipers or an appropriate wiper speed for the level of rain or precipitation. The rain sensor may require a particular optical transparency that is different from the optical transparency of the first sensor (i.e., the LIDAR sensor). Therefore, using the same polymer material used for one patch may not provide the required characteristics, such as light transmittance, for a second (or subsequent) patch area.

[0010] In summary, it is now common to have high performance laminates with one or more sensors that may have different functions. The sensors may also have different requirements, such as the need for different visible transmittances to operate or function properly. There is a need in the art for the development of multilayer glass panels or laminates that have good optical properties desirable in multilayer glass panels and excellent sensor compatibility with one or more sensors. Summary of the Invention

[0011] Because of these and other problems in the art, described herein is a multilayer panel or laminated glass that includes, among other things, a first rigid substrate, a first polymer interlayer, and a second rigid substrate, the multilayer panel having sensor areas for at least a first sensor and a second sensor, the first polymer interlayer having a solar absorption capability with a first visible light transmittance, the first sensor area including a second polymer interlayer selected to provide a first optically transparent area in the first sensor area, the first optically transparent area having a second light transmittance selected to allow the first sensor to operate, the second sensor area including a third polymer interlayer selected to provide a second optically transparent area in the second sensor area, the second optically transparent area having a third light transmittance selected to allow the second sensor to operate, and the first polymer interlayer, second polymer interlayer, and third polymer interlayer being different as further described below.

[0012] In one aspect, a multilayer panel includes a first rigid substrate, a first polymer interlayer, and a second rigid substrate, the multilayer panel having sensor regions for at least a first sensor and a second sensor, the first polymer interlayer having a solar absorption capability with a first optical transmittance of less than 90% at about 905 nm, the first sensor region including a second polymer interlayer selected to enable a first optically transparent region in the first sensor region, the first optically transparent region having a second optical transmittance of greater than 90% at about 905 nm, the second sensor region including a third polymer interlayer selected to enable a second optically transparent region in the second sensor region, the second optically transparent region having a third optical transmittance of greater than about 16% and less than about 85% at about 850 nm, and the first polymer interlayer, the second polymer interlayer, and the third polymer interlayer are different.

[0013] In another aspect, a multilayer panel includes a first rigid substrate, a first polymer interlayer, and a second rigid substrate, the multilayer panel having sensor areas for at least a first sensor and a second sensor, the first polymer interlayer having a solar absorption capability with a first visible light transmittance of less than 90% at about 905 nm, the first sensor area including a second polymer interlayer selected to enable a first optically transparent area in the first sensor area, the first optically transparent area having a second light transmittance of greater than 90% at about 905 nm, the second sensor area including a coating on at least one of the first rigid substrate, the second rigid substrate, and / or the second polymer interlayer selected to enable a second optically transparent area in the second sensor area, the second optically transparent area having a third light transmittance of greater than about 16% and less than about 85% at about 850 nm, the first polymer interlayer and the second polymer interlayer being different.

[0014] In another aspect, a multilayer panel includes a first rigid substrate, a first polymer interlayer, and a second rigid substrate, the multilayer panel having sensor areas for at least a first sensor and a second sensor, the first polymer interlayer having a solar absorption capability with a first visible light transmittance of less than 90% at about 905 nm, the first sensor area including a second polymer interlayer selected to enable a first optically transparent area in the first sensor area, and the first optically transparent area. The region has a second visible light transmittance greater than 90% at about 905 nm, the second sensor region comprising a pattern on at least one of the first rigid substrate, the second rigid substrate, and / or the second polymer interlayer selected to enable a second optically transparent region in the second sensor region, the second optically transparent region having a third visible light transmittance greater than about 16% and less than about 85% at about 850 nm, and the first polymer interlayer and the second polymer interlayer are different.

[0015] In another aspect, in one aspect, a multilayer panel includes a first rigid substrate, a first polymer interlayer, and a second rigid substrate, the multilayer panel having sensor areas for at least a first sensor and a second sensor, the first polymer interlayer having a solar absorption capability with a first light transmittance of less than 90% at about 905 nm, the first sensor area including a second polymer interlayer selected to enable a first optically transparent area in the first sensor area, the first optically transparent area having a second light transmittance of greater than 90% at about 905 nm, the second sensor area including a third polymer interlayer having a pigment, dye, or other additive selected to enable a second optically transparent area in the second sensor area, the second optically transparent area having a third light transmittance of greater than about 16% and less than about 85% at about 850 nm, and the first polymer interlayer, the second polymer interlayer, and the third polymer interlayer are different.

[0016] A method for making a multi-layer panel is also disclosed.

[0017] In an embodiment, the multi-layer panel or laminated glass is a vehicle windshield. In an embodiment, the laminated glass is used in a head-up display application.

[0018] In certain embodiments, the rigid substrate(s) is glass. In embodiments, the glass is low iron glass or ultra clear glass. [Brief explanation of the drawings]

[0019] [Figure 1] FIG. 1 is a diagram of a windshield showing the area where the sensors are mounted. [Figure 2a] FIG. 1 is an enlarged view of the rain sensor area of ​​a windshield having a coating. [Figure 2b] FIG. 1 is a close-up view of the rain sensor area of ​​the patterned windshield. [Figure 3] FIG. 10 is a diagram of an interlayer blank showing the sensor area where a notch may occur. [Figure 4]FIG. 10 is a diagram of an interlayer blank showing the sensor areas for two sensors where two different cutouts can occur. DETAILED DESCRIPTION OF THE INVENTION

[0020] Described herein, among other things, is a multi-layer panel or laminated glass comprised of first and second rigid substrates and a polymer interlayer. The laminated glass of the present disclosure has improved compatibility with various sensors.

[0021] For laminated glass, such as windshields, particularly for electric vehicles, it is desirable to have good solar absorption capabilities in the laminated glass(es). It is also desirable to have multiple sensors in the laminated glass for different functions. Different sensors have different requirements to function. For example, some sensors, such as LIDAR sensors, must maintain a visible transmittance level (also called visible light transmittance) of at least 90% or greater at about 905 nm. Other sensors require a different range; for example, a rain sensor must maintain a specific visible light transmittance (%T) of greater than 16% and less than 85% at about 850 nm. Still other sensors require different levels of visible transmittance.

[0022] Laminated glass with high solar absorption capacity has too low visible light transmittance for LIDAR sensors to function properly. Patches of solar-absorbing materials or materials such as transparent polymers without solar absorption capacity can be used to provide the required level of visible light transmittance. However, if a second (or third or more) sensor is also used in the same area of ​​the laminated glass, the visible light transmittance of the patch material (i.e., transparent polymer) used for the first sensor or the visible light transmittance of the solar-absorbing polymer may not be appropriate for the sensor. For example, a particular solar-absorbing material may start with an appropriate level of visible light transmittance, but if, for example, a rain sensor is placed on the laminated glass, over time and with exposure to solar or other ultraviolet light, the visible light transmittance level may change (or decrease) due to photodarkening of the polymer, and the sensor may not function. Alternatively, if a transparent patch is used to enable very high visible light transmittance for some sensors, such as LIDAR sensors that require more than 90% visible light transmittance at 905 nm, the visible light transmittance level may be too high for certain sensors, such as rain sensors. The inventors have found a way to solve this problem, as described below.

[0023] In multi-layer panels, such as windshields, it has become common to use material patches or pieces when different functions or properties are desired. Windshields are often constructed by placing a polymer interlayer between two pieces of glass. The polymer interlayer is sometimes called a windshield "blank," and the blank is often cut from a roll of polymer material. In the past, it was sometimes necessary to remove the polymer interlayer (thereby creating a cutout) in one or more sections of the windshield. In some cases, the removed section is replaced with a different piece of polymer material cut to the same size and shape as the cutout section. The patch is placed where the cutout was removed.

[0024] To achieve desired optical transparency and other necessary properties in multiple regions of the laminate, or for multiple sensors such as LIDAR and rain sensors, two or more different polymer interlayers may be used as patches to provide different properties in portions of the laminate. For example, a "patch" or piece of polymer material different from the main polymer (or bulk material of the laminate) and / or another patch may be used in one or more portions to provide different properties. A first polymer interlayer can provide a first visible light transmittance value, and a second polymer interlayer can provide a second visible light transmittance value.

[0025] Depending on the particular type of interlayer and / or interlayer patch used, the interlayer and / or patch may have some instability after prolonged exposure to intense solar radiation. The sunlight or color additives in the interlayer may fade over time and exposure, becoming lighter or darker, which may result in higher or lower transmittance levels than the original state. These changes must be taken into account when considering the particular composition of the interlayer patch.

[0026] FIG. 1 shows a diagram of a windshield 10 showing areas where sensors such as LIDAR sensors and rain sensors may be placed. In FIG. 1, there is a dark or black coating or frit 20 around the outside of the windshield. This frit 20 continues to a sensor area 30. In the illustrated example, the sensor area 30 has cutouts or areas for two different sensors. There is a first, larger sensor area 40 where a sensor such as a LIDAR sensor may be placed, and a second, smaller sensor area 50 where a rain sensor or other sensor may be placed.

[0027] Figures 2a and 2b show close-up views of smaller sensor areas 50. Each of the sensor areas 50 has frit 20 around the sensor area opening. In Figure 2a, the sensor area opening is shown as 70 and is coated glass (coating not shown). In Figure 2b, the sensor area opening is shown as 60 and is a pattern.

[0028] In an alternative embodiment, a coating or pattern (as shown in Figures 2a and 2b) may be used on one or more of the rigid substrates (i.e., glass) to adjust the visible light transmittance value to an appropriate level, thereby enabling the use of only one patch of a single polymer interlayer instead of multiple patches. The coating or pattern is selected to change the light transmittance value in a particular wavelength range to a desired range, such as reducing the visible light transmittance to 16% to 85% at approximately 850 nm for a particular application such as a rain sensor. Different ranges and wavelengths may be selected depending on the sensor(s) and application. The coating and / or pattern may be applied to the rigid substrate, to a film layer (such as a PET layer) included within or with the interlayer, or directly to the interlayer using any method known to those skilled in the art. For example, the coating may be applied to the interlayer using layer-by-layer (LbL) techniques for multi-layer application to achieve the desired color and / or visible transmittance level. Alternatively, the coating may be applied to the rigid substrate by any method known to those skilled in the art. Examples of methods for applying coatings onto rigid substrates, interlayers, or PET films include, but are not limited to, rotogravure printing, flexographic printing, and digital printing. Examples of coatings and pattern printing on glass used in automotive applications typically involve ceramic frit coating. The ceramic frit is baked into the glass using high temperatures.

[0029] Figure 3 shows an example of an interlayer blank 80 with cutouts 90 where one or more sensors can be placed. A patch of material is filled into the cutout. Figure 4 is another example of an interlayer blank 180 showing a sensor portion 200 where two sensors can be placed, with a first cutout 190 for a first patch and a second cutout 100 for a second patch of a different material.

[0030] The polymer interlayer (including any patch) may be a single-layer or multilayer polymer interlayer, and the interlayer (or any layer) may be prepared by blending one or more polymer resins, such as poly(vinyl acetal) resins (e.g., PVB), with one or more plasticizers. Multilayer interlayers generally contain two or more layers and two or more resins of different compositions. For example, poly(vinyl acetal) resins, such as PVB resins, with different residual hydroxyl and / or residual acetic acid contents are suitable for the composition of multilayer interlayers. In multilayers containing two layers, at least one of the two layers is a soft layer and the other layer is a hard layer. As used herein, a "soft layer" or "softer layer" is a layer having a glass transition temperature of less than about 20°C. As used herein, a "hard layer" or "harder layer" generally refers to a layer that is harder and stiffer than another layer and generally has a glass transition temperature at least two degrees (2°C) higher than another layer (e.g., a softer layer).

[0031] The multilayer interlayer formed from the composition comprises two or more glass transitions, the lowest glass transition occurring below 20°C, or below 15°C, or below 10°C, or below 5°C, or below 0°C, or below -5°C, or below -10°C.

[0032] Conventional multilayer interlayers, such as triple-layer acoustic interlayers, include a soft core layer made of a single poly(vinyl butyral) (“PVB”) resin with a low residual hydroxyl content and a large amount of conventional plasticizers, and two hard skin layers with significantly higher residual hydroxyl content (see, e.g., U.S. Pat. Nos. 5,340,654, 5,190,826, and 7,510,771). The residual hydroxyl content and amount of plasticizer in the PVB core resin are optimized so that the interlayer provides optimal sound insulation properties under ambient conditions for multiple layer glass panels, such as windshields and windows installed in vehicles and buildings.

[0033] Here, a multilayer acoustical interlayer, such as a three-layer, can be designed and manufactured by (1) selecting a plasticizer or plasticizer blend, (2) selecting resin(s) for the surface layer(s) and core layer(s), (3) maintaining a plasticizer balance between the core layer(s) and the surface layer(s) (such as by selecting resins with specific properties), and (4) combining the core layer(s) and the surface layer(s) to form a multilayer interlayer by an applicable process such as coextrusion or lamination. The resulting multilayer acoustical interlayer provides excellent clarity and sound insulation properties without sacrificing other desirable properties of conventional multilayer interlayers, such as the optical properties and mechanical strength of glass panels made with the multilayer acoustical interlayer.

[0034] Some terminology and common components found in interlayers, both generally and in the interlayers of the present disclosure, and their formation will now be described. As used herein, the terms "polymer interlayer sheet," "interlayer," and "polymer melt sheet" may generally refer to a monolayer sheet or a multilayer interlayer. A "monolayer sheet," as the name suggests, is a single polymer layer extruded as one layer. A multilayer interlayer, on the other hand, may include multiple layers, including separately extruded layers, coextruded layers, or any combination of separately extruded and coextruded layers. Thus, a multilayer interlayer may include, for example, two or more monolayer sheets combined together (a "multilayer sheet"), two or more layers coextruded together (a "coextruded sheet"), two or more coextruded sheets bonded together, a combination of at least one monolayer sheet and at least one coextruded sheet, a combination of a monolayer sheet and a multilayer sheet, and a combination of at least one multilayer sheet and at least one coextruded sheet. In various embodiments of the present disclosure, a multilayer interlayer includes at least two polymer layers (e.g., a single layer, or multiple layers coextruded and / or laminated together) disposed in direct contact with one another, each layer comprising a polymer resin, as described more fully below. As used herein with respect to a multilayer interlayer having at least three layers, "surface layer" generally refers to the outer layer of the interlayer, and "core layer" generally refers to the inner layer(s). Thus, one exemplary embodiment is surface layer / / core layer / / surface layer. In a multilayer interlayer having a surface layer / / core layer / / surface layer configuration, in some embodiments, the surface layer may be harder and the core layer may be softer, while in other embodiments, the surface layer may be softer and the core layer may be harder.

[0035] Poly(vinyl acetal) resins are produced by known acetalization processes, such as reacting polyvinyl alcohol ("PVOH") with one or more aldehydes, such as butyraldehyde, in the presence of an acid catalyst, followed by isolating, stabilizing, and drying the resin. Such acetalization processes are described, for example, in U.S. Pat. Nos. 2,282,057 and 2,282,026, and Wade, B. 2016, "Vinyl Acetal Polymers," Encyclopedia of Polymer Science and Technology, pp. 1-22 (online, copyright 2016 John Wiley & Sons, Inc.), which are incorporated herein by reference in their entireties. Resins are commercially available in various forms, such as Butvar® resins from Solutia Inc., a wholly owned subsidiary of Eastman Chemical Company.

[0036] As used herein, the residual hydroxyl content (calculated as the weight percent of vinyl alcohol or the weight percent of PVOH) in a poly(vinyl acetal) resin refers to the amount of hydroxyl groups remaining on the polymer chain after processing is complete. For example, PVB can be produced by hydrolyzing poly(vinyl acetate) to poly(vinyl alcohol) (PVOH) and then reacting the PVOH with butyraldehyde. In the process of hydrolyzing poly(vinyl acetate), not all of the acetate side groups are typically converted to hydroxyl groups. Furthermore, the reaction with butyraldehyde does not typically convert all of the hydroxyl groups to acetal groups. As a result, in any finished PVB resin, there will typically be residual acetate groups (as vinyl acetate groups) and residual hydroxyl groups (as vinyl hydroxyl groups) present as side groups on the polymer chain. As used herein, the residual acetate content (calculated as the weight percent vinyl acetate content or poly(vinyl acetate) (PVA) content in the poly(vinyl acetal)) refers to the amount of residues remaining on the polymer chain. As used herein, residual hydroxyl content and residual acetic acid content are measured on a weight percent (wt%) basis according to ASTM D1396.

[0037] In embodiments, when the multilayer interlayer of the present invention is three-layered, the core layer is a soft layer and the surface layers are hard layers. In other embodiments, the core layer is hard and the surface layers are softer. Other combinations and numbers of layers are possible.

[0038] In various embodiments, when the intermediate layer is a multi-layer intermediate layer, such as a three-layer, the flexible (or core) layer comprises a poly(vinyl acetal) resin (or first resin) containing from about 7 to about 16 weight percent (wt.%) hydroxyl groups, calculated as % PVOH, such as from about 7 to about 14 wt.%, from about 9 to about 14 wt.%, from about 8.5 to about 12 wt.%, and for certain embodiments, from about 11 to about 13 wt.% hydroxyl groups, calculated as % PVOH, although other amounts are possible. The resin may also contain less than 30 wt.% residual acetate groups, calculated as poly(vinyl acetate), less than 25 wt.%, less than 20 wt.%, less than 15 wt.%, less than 13 wt.%, less than 10 wt.%, less than 7 wt.%, less than 5 wt.%, less than 1 wt.%, or less than 0.5 wt.%, or in the range of 0 to 30 wt.%, 1 to 30 wt.%, 2 to 25 wt.%, 5 to 20 wt.%, or 7 to 15 wt.%, with the remainder being acetals such as butyraldehyde (including isobutyraldehyde acetal groups), and optionally other acetal groups such as 2-ethylhexanal acetal groups, or a mixture of butyraldehyde acetal groups and 2-ethylhexanal acetal groups.

[0039] In various embodiments, when the intermediate layer is a multilayer intermediate layer, such as a three-layer, the hard (or skin) layer(s) comprise a poly(vinyl acetal) resin having residual hydroxyls that are at least 2 wt.%, or at least 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, or 20 wt.% or more greater than the residual hydroxyl content of the resin in the soft (or core) layer, and the resin in the skin layers can comprise from about 15 to about 35 wt.%, from about 15 to about 30 wt.%, or from about 17 to about 22 wt.%, and for certain embodiments, from about 17.25 to about 22.25 wt.% residual hydroxyl groups, calculated as % PVOH, although other amounts are possible depending on the desired properties.

[0040] This difference between poly(vinyl acetal) resins is calculated by subtracting the residual hydroxyl content of the resin with the lower residual hydroxyl content from the residual hydroxyl content of the resin with the higher residual hydroxyl content. As used herein, the terms "different by weight percent" or "difference is at least ... weight percent" refer to the difference between two given weight percents calculated by subtracting one number from the other. For example, a poly(vinyl acetal) resin with a residual hydroxyl content of 12 weight percent has a residual hydroxyl content that is 2 weight percent less than a poly(vinyl acetal) resin with a residual hydroxyl content of 14 weight percent (14 weight percent - 12 weight percent = 2 weight percent). As used herein, the term "different" can refer to a value that is higher or lower than another value. One or more other poly(vinyl acetal) layers may also be present in the intermediate layer and may have residual hydroxyls within the above ranges. Additionally, the residual hydroxyl content of the one or more other poly(vinyl acetal) resins may be the same as or different from the residual hydroxyl content of the first and / or second poly(vinyl acetal) resin.

[0041] In various embodiments, the poly(vinyl acetal) resin for the soft layer or the poly(vinyl acetal) resin for the hard layer(s) may also contain less than 30 wt.% residual acetate groups, calculated as poly(vinyl acetate), less than 25 wt.%, less than 20 wt.%, less than 15 wt.%, less than 13 wt.%, less than 10 wt.%, less than 7 wt.%, less than 5 wt.%, or less than 1 wt.% residual acetate groups, with the remainder being acetals such as butyraldehyde (including isobutyraldehyde acetal groups), as described above, but optionally other acetal groups such as 2-ethylhexanal acetal groups or a mixture of butyraldehyde acetal groups and 2-ethylhexanal acetal groups.

[0042] In some embodiments, the first and second poly(vinyl acetal) resins can have different residual acetic acid contents. For example, in some embodiments, the difference in residual acetic acid content between the first poly(vinyl acetal) resin and the second poly(vinyl acetal) resin can be at least about 2, at least about 3, at least about 4, at least about 5, at least about 6, at least about 7, at least about 8, at least about 9, at least about 10, at least about 12, at least about 14, at least about 16, at least about 18, at least about 20, at least about 24, or at least 29 weight percent. One of the poly(vinyl acetal) resins can have a residual acetic acid content of about 4 or less, about 3 or less, about 2 or less, or about 1 or less, measured as described above. In some embodiments, one of the first and second poly(vinyl acetal) resins may have a residual acetic acid content of at least 4, at least about 5, at least about 6, at least about 7, about 8, at least about 10, at least about 12, at least about 14, at least about 16, at least about 18, at least about 20, at least about 25, or at least about 30 weight percent. In other embodiments, the first and second poly(vinyl acetate) resins may both have a residual acetic acid content of at least 4, at least about 5, at least about 6, at least about 7, about 8, at least about 10, at least about 12, at least about 14, at least about 16, at least about 18, or at least about 20 weight percent. The difference in residual acetic acid content between the first and second poly(vinyl acetal) resins may be within the above ranges, or the difference may be less than about 3, not more than about 2, not more than about 1, or not more than about 0.5 weight percent. The additional poly(vinyl acetal) layer present in the intermediate layer can have a residual acetic acid content that is the same as or different from the residual acetic acid content of the first and / or second poly(vinyl acetal) resins.

[0043] Poly(vinyl acetal) resins, such as the poly(vinyl butyral) (PVB) resin(s) of the present disclosure, typically have a molecular weight of greater than 50,000 daltons, or less than 500,000 daltons, or from about 50,000 to about 500,000 daltons, or from about 70,000 to about 500,000 daltons, or from about 100,000 to about 425,000 daltons, as measured by size exclusion chromatography using a low-angle laser light scattering detector, a differential refractometer, or a UV detector. As used herein, the term "molecular weight" refers to weight average molecular weight.

[0044] Various adhesion control agents ("ACAs") can be used in the interlayers of the present disclosure to control adhesion of the interlayer sheet to glass. In various embodiments of the interlayer of the present disclosure, the interlayer can include from about 0.003 to about 0.15 parts ACA per 100 parts resin, from about 0.01 to about 0.10 parts ACA per 100 parts resin, or from about 0.01 to about 0.04 parts ACA per 100 parts resin. Such ACAs include, but are not limited to, the ACAs disclosed in U.S. Pat. No. 5,728,472 (the entire disclosure of which is incorporated herein by reference), sodium acetate, potassium acetate, magnesium bis(2-ethylbutyrate), and / or magnesium bis(2-ethylhexanoate).

[0045] Other additives can be incorporated into the interlayer to enhance its performance in the final product or to impart specific additional properties to the interlayer. Such additives include, but are not limited to, dyes, pigments, stabilizers (e.g., UV stabilizers), antioxidants, antiblocking agents, flame retardants, IR absorbers or blockers (e.g., indium tin oxide, antimony tin oxide, lanthanum hexaboride (LaB6), and cesium tungsten oxide), processing aids, flow promoters, lubricants, impact modifiers, nucleating agents, heat stabilizers, UV absorbers, dispersants, surfactants, chelating agents, coupling agents, adhesives, primers, reinforcing additives, and fillers, among other additives known to those skilled in the art.

[0046] In various embodiments, the plasticizer may be selected from a high refractive index plasticizer, a mixture of two or more high refractive index plasticizers, or a mixture of a conventional plasticizer and one or more high refractive index plasticizer(s).

[0047] As used herein, plasticizers having a refractive index of about 1.450 or less are referred to as "conventional plasticizers." Conventional plasticizers include, but are not limited to, triethylene glycol di(2-ethylhexanoate) ("3GEH"), triethylene glycol di(2-ethylbutyrate), triethylene glycol diheptanoate, tetraethylene glycol diheptanoate, tetraethylene glycol di(2-ethylhexanoate), dihexyl adipate, dioctyl adipate, hexylcyclohexyl adipate, diisononyl adipate, heptylnonyl adipate, di(butoxyethyl) adipate, and bis(2-(2-butoxyethoxy)ethyl) adipate, dibutyl sebacate, dioctyl sebacate, and mixtures thereof. These plasticizers have a refractive index of about 1.442 to about 1.449. By comparison, PVB resin has a refractive index of approximately 1.485 to 1.495. In interlayers manufactured for a variety of properties and applications, 3GEH (refractive index = 1.442) is one of the most common plasticizers present.

[0048] In various embodiments, one or more high refractive index plasticizer(s) may be used. In embodiments, the high refractive index plasticizer(s) are selected so that the refractive index of the plasticizer is at least about 1.460, or greater than about 1.460, or greater than about 1.470, or greater than about 1.480, or greater than about 1.490, or greater than about 1.500, or greater than about 1.510, or greater than about 1.520, in both the core layer and / or the surface layer. As used herein, a "high refractive index plasticizer" is a plasticizer having a refractive index of at least about 1.460. In some embodiments, the high refractive index plasticizer(s) are used in conjunction with a conventional plasticizer; in some embodiments, the conventional plasticizer, if included, is triethylene glycol di-(2-ethylhexanoate) ("3GEH"), and the refractive index of the plasticizer mixture is at least 1.460. As used herein, the refractive index of the plasticizers or resins used throughout this disclosure is measured at a wavelength of 589 nm and 25° C. according to ASTM D542, or as reported in the literature according to ASTM D542.

[0049] Examples of plasticizers with high refractive index that can be used include, but are not limited to, polyadipates (RI of about 1.460 to about 1.485), epoxides (RI of about 1.460 to about 1.480), phthalates and terephthalates (RI of about 1.480 to about 1.540), benzoates (RI of about 1.480 to about 1.550), and other specialty plasticizers (RI of about 1.490 to about 1.520). Specific examples of suitable high refractive index plasticizers include dipropylene glycol dibenzoate, tripropylene glycol dibenzoate, polypropylene glycol dibenzoate, isodecyl benzoate, 2-ethylhexyl benzoate, diethylene glycol benzoate, propylene glycol dibenzoate, 2,2,4-trimethyl-1,3-pentanediol dibenzoate, 2,2,4-trimethyl-1,3-pentanediol benzoate isobutyrate, 1,3-butanediol dibenzoate, and diethylene glycol di-o-toluate. esters of benzoic acid esters of dipropylene glycol and diethylene glycol, and mixtures thereof.

[0050] The total content of plasticizer in the intermediate layer may be 0 to 120 phr, or greater than 0 phr, or greater than 5 phr, or greater than 10 phr, or greater than 15 phr, or greater than 20 phr, or greater than 25 phr, or greater than 30 phr, and / or 120 phr or less, or 115 phr or less, or 110 phr or less, or 105 phr or less, or 100 phr or less, or 95 phr or less, or 90 phr or less, or 85 phr or less, or 80 phr or less, or 75 phr or less, or 70 phr or less, or in the range of 10 to 100 phr, or in the range of 20 to 80 phr, or in the range of 30 to 70 phr. In various embodiments of the interlayer of the present disclosure, the interlayer comprises a total amount of plasticizer greater than 5 phr, from about 5 to about 120 phr, from about 10 to about 90 phr, from about 20 to about 70 phr, from about 30 to about 60 phr, or less than 120 phr, or less than 90 phr, or less than 60 phr, or less than 40 phr, or less than 30 phr. While the total plasticizer content is indicated above, the plasticizer content in the surface layer(s) or core layer(s) may differ from the total plasticizer content. Furthermore, as disclosed in U.S. Pat. No. 7,510,771 (the entire disclosure of which is incorporated herein by reference), the surface layer(s) and core layer(s) may have different plasticizer types and plasticizer contents within the ranges indicated above, since the plasticizer content of each layer at equilibrium is determined by the respective residual hydroxyl content of that layer. For example, at equilibrium, an intermediate layer may include two surface layers each having 30 phr of plasticizer and a core layer having 65 phr of plasticizer, with the total surface layer thickness equal to the core layer thickness, resulting in a total intermediate layer plasticizer content of approximately 45.4 phr. For thicker or thinner surface layers, the total intermediate layer plasticizer content may vary accordingly. As used herein, when the plasticizer content of an intermediate layer is given, the plasticizer content is determined with reference to the phr of plasticizer in the mixture or melt used to produce the intermediate layer.

[0051] The amount of plasticizer in the interlayer is determined by the glass transition temperature (T g ) and final acoustic performance.g ) is the temperature that characterizes the transition from the glassy state to the rubbery state of the interlayer. Generally, the higher the amount of plasticizer, the higher the T g Conventional and previously utilized interlayers generally have a T range of approximately -10 to 25°C for acoustic (noise-reducing) interlayers. g and a T range of up to about 45°C for hurricane and aircraft (harder or structural) interlayer applications. g The glass transition temperature (T g ) can be determined by dynamic mechanical thermal analysis (DMTA) in shear mode. DMTA measures the storage (elastic) modulus in Pascals (G'), loss (viscous) modulus in Pascals (G"), and tan delta (= G' / G') of a specimen as a function of temperature at a given frequency and temperature sweep rate. Here, a frequency of 1 Hz and a temperature sweep rate of 3°C / min were used. T g is determined by the location of the tan delta peak on the °C temperature scale, and the peak value of tan delta is referred to as tan delta or peak tan delta. As used herein, "tan delta," "peak tan delta," "tan δ," and "peak tan δ" may be used interchangeably.

[0052] The glass transition temperature (T g ) also correlates with the hardness of the interlayer; generally, the higher the glass transition temperature, the harder the interlayer. Generally, interlayers having a glass transition temperature of 30°C or higher improve the mechanical strength and torsional rigidity of the windshield. Meanwhile, softer layers or interlayers (generally characterized by layers or interlayers having a glass transition temperature below 20°C) contribute to the acoustic attenuation effect (i.e., acoustic properties). Interlayers of the present disclosure may have glass transition temperatures of about 26°C or higher, or about 35°C or higher for the harder layer(s), and about 20°C or lower, or 15°C or lower, or 10°C or lower, or 5°C or lower, or 0°C or lower, or about -5°C or lower, or about -10°C or lower for the softer layer(s), although other glass transition temperatures are possible depending on the desired performance and properties.

[0053] In some embodiments, the multilayered interlayer of the present disclosure combines these two advantageous properties (i.e., strength and acoustics) by utilizing harder or stiffer surface layers (e.g., hard / soft / hard) laminated with a softer core layer. In various embodiments, the multilayered interlayer generally includes a harder layer(s) comprising poly(vinyl acetal) resin(s) having a glass transition temperature of about 26°C to about 60°C, about 26°C to 40°C, about 26°C or higher, about 30°C or higher, or about 35°C or higher, and a softer layer(s) at about 20°C or lower, about 10°C or lower, about 5°C or lower, about 0°C or lower, about -5°C or lower, or about -10°C or lower.

[0054] The final intermediate layer, whether formed by extrusion or coextrusion, or lamination of multiple layers, will generally have a randomly roughened surface topography because it is formed through melt fracture of the polymer melt as it exits the extrusion die, and may further be embossed onto the randomly roughened surface on one or both sides (e.g., the surface layer) by any embossing method known to those skilled in the art.

[0055] While all methods for producing polymer interlayer sheets known to those skilled in the art are contemplated as possible methods for producing the polymer interlayer sheets described herein, this application focuses on polymer interlayer sheets produced by extrusion and coextrusion processes. The final multiple layer glass panel laminate of the present invention is formed using lamination processes known in the art.

[0056] Typically, the thickness, or gauge, of the polymer interlayer sheet ranges from about 15 mils to about 100 mils (about 0.38 mm to about 2.54 mm), about 15 mils to about 60 mils (about 0.38 mm to about 1.52 mm), about 20 mils to about 50 mils (about 0.51 mm to about 1.27 mm), and about 15 mils to about 35 mils (about 0.38 mm to about 0.89 mm). In various embodiments, each of the layers, such as the surface and core layers of the multilayer interlayer, can have a thickness of about 1 mil to about 99 mils (about 0.025 mm to about 2.51 mm), about 1 mil to about 59 mils (about 0.025 mm to about 1.50 mm), 1 mil to about 29 mils (about 0.025 mm to about 0.74 mm), or about 2 mils to about 28 mils (about 0.05 mm to about 0.71 mm), although other thicknesses may be selected depending on the desired performance and properties.

[0057] In many of the embodiments described below, the polymer resin is referred to as PVB, however, it will be understood by those skilled in the art that the polymer may be any polymer suitable for use in multiple layer panels. Typical polymers include, but are not limited to, polyvinyl acetal (PVA) (such as poly(vinyl butyral) (PVB) or poly(vinyl isobutyral), an isomer of poly(vinyl butyral), also known as PVisoB, aliphatic polyurethanes (PU), poly(ethylene-co-vinyl acetate) (EVA), polyvinyl chloride (PVC), poly(vinyl chloride-co-methacrylate), polyethylene, polyolefins, ethylene acrylate ester copolymers, poly(ethylene-co-butyl acrylate), silicone elastomers, epoxy resins, and acid copolymers such as ethylene / carboxylic acid copolymers and ionomers thereof derived from any of the aforementioned possible thermoplastic resins, combinations of the foregoing, and the like. PVB and its isomer polyvinyl isobutyral, polyvinyl chloride, ionomers, and polyurethanes are generally suitable polymers for the interlayer, with PVB (including its isomer PVisoB) being particularly preferred.

[0058] Examples of illustrative multilayer interlayer structures include, but are not limited to, PVB / PVisoB / PVB (where the PVisoB layers contain two or more resins with different residual hydroxyl and / or acetic acid contents or different polymer compositions), and PVC / PVB / PVC, PU / PVB / PU, ionomer / PVB / ionomer, ionomer / PU / ionomer, ionomer / EVA / ionomer (where the core layer PVB (including PVisoB), PU, ​​or EVA may contain a single resin with one glass transition or two or more resins with different glass transitions). Alternatively, the surface and core layers may all be PVBs with the same or different residual hydroxyl and / or acetic acid contents, and the same or different plasticizers, using the same or different starting resins. Other combinations of resins and polymers will be apparent to those skilled in the art.

[0059] Poly(vinyl acetal) resins, commonly referred to as poly(vinyl acetal) or poly(vinyl butyral), may contain residues of any suitable aldehyde, such as isobutyraldehyde, as described above. In some embodiments, one or more poly(vinyl acetal) resins contain at least one C1-C 10The aldehyde may comprise a residue of an aldehyde or at least one C4-C8 aldehyde. Examples of suitable C4-C8 aldehydes may include, but are not limited to, n-butyraldehyde, isobutyraldehyde, 2-methylvaleraldehyde, n-hexylaldehyde, 2-ethylhexylaldehyde, n-octylaldehyde, and combinations thereof. At least one of the first and second poly(vinyl acetal) resins may contain at least about 20, at least about 30, at least about 40, at least about 50, at least about 60, or at least about 70 weight percent of residues of at least one C4-C8 aldehyde, and / or may contain up to about 90 weight percent, up to about 85 weight percent, up to about 80 weight percent, up to about 75 weight percent, up to about 70 weight percent, or up to about 65 weight percent of at least one C4-C8 aldehyde, based on the total weight of aldehyde residues of the resin. The C4-C8 aldehyde may be selected from the group described above or may be selected from the group consisting of n-butyraldehyde, isobutyraldehyde, 2-ethylhexylaldehyde, and combinations thereof.

[0060] In various embodiments, the one or more poly(vinyl acetal) resins can be poly(vinyl butyral) (PVB) resins. In other embodiments, the one or more poly(vinyl acetal) resins can be poly(vinyl butyral) resins, which comprise primarily residues of n-butyraldehyde and can contain, for example, about 50 weight percent or less, about 40 weight percent or less, about 30 weight percent or less, about 20 weight percent or less, about 10 weight percent or less, about 5 weight percent or less, or about 2 weight percent or less of residues of aldehydes other than butyraldehyde, based on the total weight of all aldehyde residues of the resin.

[0061] As used herein, a multilayer panel may comprise a single substrate, such as glass, acrylic, or polycarbonate (or other rigid substrate), onto which a polymer interlayer sheet is disposed, most commonly a polymer film disposed on top of the polymer interlayer. The combination of a polymer interlayer sheet and a polymer film is commonly referred to in the art as a bilayer. A typical multilayer panel having a bilayer structure is (glass) / / (polymer interlayer sheet) / / (polymer film), where the polymer interlayer sheet may include multiple interlayers as described above. The polymer film provides a smooth, thin, rigid substrate that provides superior optical properties to those typically achieved with the polymer interlayer sheet alone, and functions as a performance-enhancing layer. The polymer film differs from the polymer interlayer sheet used herein in that the polymer film does not by itself provide the necessary puncture resistance and glass retention properties, but rather improves performance such as infrared absorption properties. Poly(ethylene terephthalate) (“PET”) is the most commonly used polymer film. Generally, as used herein, a polymer film is thinner than a polymer sheet, for example, about 0.001 to 0.2 mm thick, although other thicknesses may also be used.

[0062] Multilayer panels, such as windshields described herein, generally include two substrates, such as a pair of glass sheets (or other rigid materials known in the art, such as polycarbonate or acrylic), with an interlayer(s) disposed between the two substrates. An example of such a construction is (glass) / / (polymer interlayer sheet) / / (glass), where the polymer interlayer sheet, as described above, may include a multi-layer interlayer and may have one or more patches or portions made of different polymer materials. These examples of multilayer panels are not intended to be limiting in any way, and one of skill in the art will readily recognize that numerous structures other than those described above can be made using the interlayers of the present disclosure.

[0063] A typical glass lamination process includes the steps of (1) assembling two substrates (e.g., glass) and an interlayer, (2) briefly heating the assembly by IR radiation or convection, (3) passing the assembly through pressure nip rolls to perform a first degassing step, (4) heating the assembly again to about 60°C to about 120°C to provide sufficient temporary adhesion to the assembly and seal the edges of the interlayer, (5) passing the assembly through a second pressure nip roll to further seal the edges of the interlayer and allow for further handling, and (6) autoclaving the assembly at a temperature of about 135°C to 150°C and a pressure of about 180 psig to 200 psig for about 30 to 90 minutes. The actual steps, as well as times and temperatures, can be varied as needed, as known to those skilled in the art.

[0064] A cutout and patch process can be applied to modify specific regions of an interlayer to provide different or specific performance attributes. These attributes can include, but are not limited to, alterations in the UV, visible, and NIR regions of the EMI spectrum. The cutouts can be any shape and size and can be applied to any region or regions within the entire interlayer. A single cutout or multiple cutouts can be used to affect different regions of the interlayer. A patch should typically consist of an interlayer with a similar thickness and thickness profile; the patch may have similar or significantly different attributes from the interlayer to which it is patched. A cutout is a region of the interlayer that is removed from the interlayer by some form of cutting tool, such as a punch device (if multiple cutouts are used in an iterative process). A patch is constructed from an interlayer of approximately the same size, shape, and thickness as the interlayer to which it is applied, but generally has some differences, such as a different composition, additives, and / or functionality. The patch is then inserted into the original interlayer in the location of the cutout. Lamination is then carried out according to the same standard lamination practices as previously described and known by those skilled in the art.

[0065] Other means known in the art and commercially practiced for use in degassing the interlayer / glass interface (steps 2-5) include vacuum bag and vacuum ring processes that utilize a vacuum to remove air.

[0066] The present invention also includes the following aspects described below.

[0067] In one aspect, a multilayer panel includes a first rigid substrate, a first polymer interlayer, and a second rigid substrate, the multilayer panel having sensor areas for at least a first sensor and a second sensor, the first polymer interlayer having a solar absorption capability with a first visible light transmittance, the first sensor area including a second polymer interlayer selected to provide a first optically transparent area in the first sensor area, the first optically transparent area having a second light transmittance selected to allow the first sensor to operate, the second sensor area including a third polymer interlayer selected to provide a second optically transparent area in the second sensor area, the second optically transparent area having a third light transmittance selected to allow the second sensor to operate, and the first polymer interlayer, second polymer interlayer, and third polymer interlayer are different.

[0068] In another aspect, a multilayer panel includes a first rigid substrate, a first polymer interlayer, and a second rigid substrate, the multilayer panel having sensor areas for at least a first sensor and a second sensor, the first polymer interlayer having a solar absorption capability with a first light transmittance of less than 90% at about 905 nm, the first sensor area including a second polymer interlayer selected to enable a first optically transparent area in the first sensor area, the first optically transparent area having a second light transmittance of greater than 90% at about 905 nm, the second sensor area including a third polymer interlayer selected to enable a second optically transparent area in the second sensor area, the second optically transparent area having a third light transmittance of greater than about 16% and less than about 85% at about 850 nm, and the first polymer interlayer, second polymer interlayer, and third polymer interlayer are different.

[0069] In another aspect, the second polymer interlayer of any of the multilayer panels is a clear polymer interlayer. In any of the aspects, the third polymer interlayer is a colored polymer interlayer, and the colored polymer interlayer can have a color combination of green, blue, gray, bronze, or green, blue, gray, and bronze.

[0070] In another aspect, a multilayer panel includes a first rigid substrate, a first polymer interlayer, and a second rigid substrate, the multilayer panel having sensor areas for at least a first sensor and a second sensor, the first polymer interlayer having a solar absorption capability with a first visible light transmittance of less than 90% at about 905 nm, the first sensor area including a second polymer interlayer selected to enable a first optically transparent area in the first sensor area, the first optically transparent area having a second light transmittance of greater than 90% at about 905 nm, the second sensor area including a coating on at least one of the first rigid substrate, the second rigid substrate, and / or the second polymer interlayer selected to enable a second optically transparent area in the second sensor area, the second optically transparent area having a third light transmittance of greater than about 16% and less than about 85% at about 850 nm, the first polymer interlayer and the second polymer interlayer being different.

[0071] In another aspect, a multilayer panel includes a first rigid substrate, a first polymer interlayer, and a second rigid substrate, the multilayer panel having sensor areas for at least a first sensor and a second sensor, the first polymer interlayer having a solar absorption capability with a first visible light transmittance of less than 90% at about 905 nm, the first sensor area including a second polymer interlayer selected to enable a first optically transparent area in the first sensor area, and the first optically transparent area. The optically transparent region has a second visible light transmittance greater than 90% at about 905 nm, the second sensor region comprises a pattern on at least one of the first rigid substrate, the second rigid substrate, and / or the second polymer interlayer selected to enable a second optically transparent region in the second sensor region, the second optically transparent region having a third visible light transmittance greater than about 16% and less than about 85% at about 850 nm, and the first polymer interlayer and the second polymer interlayer are different.

[0072] The multi-layer panel of any embodiment may have first and second rigid substrates that are low iron or extra clear glass. The multi-layer panel of any embodiment may be a windshield.

[0073] In another aspect, a method of making a multi-layer panel includes providing a first rigid substrate; providing a first polymer interlayer and disposing the first polymer interlayer on the first rigid substrate; and providing a second rigid substrate, the first polymer interlayer having a sensor region having a first sensor region and a second sensor region, the first polymer region having a solar absorption capability with a first visible light transmittance of less than 90% at about 905 nm, the first sensor region having a first visible light transmittance of less than 90% at the first sensor region. The first optically transparent region includes a second polymer interlayer selected to enable an optically transparent region, the first optically transparent region having a second visible light transmittance of greater than 90% at about 905 nm; the second sensor region includes a third polymer interlayer selected to enable a second optically transparent region in the second sensor region, the second optically transparent region having a third visible light transmittance of greater than about 16% and less than about 85% at about 850 nm; and the first polymer interlayer, second polymer interlayer, and third polymer interlayer are different.

[0074] In any embodiment of the method for making a multi-layer panel, the second polymer interlayer can be a clear polymer interlayer, and the third polymer interlayer can be a colored polymer interlayer, which can have a color combination of green, blue, gray, bronze, or green, blue, gray, and bronze.

[0075] In another aspect, a method of making a multi-layer panel includes providing a first rigid substrate, providing a first polymer interlayer and disposing the first polymer interlayer on the first rigid substrate, and providing a second rigid substrate, the first polymer interlayer having a sensor region having a first sensor region and a second sensor region, the first polymer region having a solar absorption capability with a first visible light transmittance of less than 90% at about 905 nm, the first sensor region enabling a first optically transparent region in the first sensor region. the first optically transparent region has a second visible light transmittance greater than 90% at about 905 nm; the second sensor region comprises a pattern on at least one of the first rigid substrate, the second rigid substrate, and / or the second polymer interlayer selected to enable the second optically transparent region in the second sensor region; the second optically transparent region has a third visible light transmittance greater than about 16% and less than about 85% at about 850 nm; and the first polymer interlayer and the second polymer interlayer are different.

[0076] In another aspect, a method of making a multiple layer glass panel includes providing a first rigid substrate; providing a first polymer interlayer and disposing the first polymer interlayer on the first rigid substrate; and providing a second rigid substrate, the first polymer interlayer having a sensor region having a first sensor region and a second sensor region, the first polymer region having a solar absorption capability with a first visible light transmittance of less than 90% at about 905 nm, the first sensor region enabling a first optically transparent region in the first sensor region. the first optically transparent region has a second visible light transmittance greater than 90% at about 905 nm; the second sensor region comprises a coating on at least one of the first rigid substrate, the second rigid substrate, and / or the second polymer interlayer selected to enable a second optically transparent region in the second sensor region; the second optically transparent region has a third visible light transmittance greater than about 16% and less than about 85% at about 850 nm; and the first polymer interlayer and the second polymer interlayer are different.

[0077] In any aspect, the multilayer panel made by the methods described herein can have first and second rigid substrates that are low iron or extra clear glass. The multilayer panel of any of the methods described herein can be a windshield.

[0078] One aspect includes a multi-layer panel or laminated glass that is a windshield for an automobile or other vehicle, where the laminated glass or windshield may be used in a heads-up display application for the vehicle.

[0079] Other combinations of features are included and contemplated, as would be known to one of ordinary skill in the art.

[0080] Example Examples of different multi-layer panel configurations and patch combinations, as well as patterns or coatings, are provided below to illustrate the invention.

[0081] Example 1 Multilayer glass panels can be manufactured that include two glass substrates and a polymer interlayer. The glass panel can also optionally have multiple polymer interlayers (or multilayer interlayers), or one or more interlayers and one or more films, such as a PET film, for additional functionality. The glass substrate can include 2.3 mm thick ultra-clear glass with a very low iron content (such as commercially available Starphire® glass sold by Vitro). Low-iron, or ultra-clear, glass contains extremely low concentrations of iron. Low-iron glass is nearly colorless and exhibits very high light transmittance in the UV, visible, and NIR spectrum. The light transmittance of glass substrates less than 6 mm thick is typically greater than about 90%.

[0082] The polymer interlayer used in the glass panel has solar capabilities (commercially available as Eastman Chemical Company's Saflex® QXH1 0000S5 interlayer, which is a solar-absorbing interlayer that, when laminated, provides solar functionality of approximately 74.9% visible transmittance, 17.1% transmittance at 850 nm, and 13.6% transmittance at 905 nm). Prior to lamination, two areas of the polymer interlayer are cut out and different patches are inserted. The first patch is a clear polymer interlayer with no solar functionality (Saflex® Clear PVB interlayer, available from Eastman Chemical Company), and the second patch is a gray polymer interlayer (Saflex® RB47 654400 PVB interlayer, available from Eastman Chemical Company). The visible light transmittance is then measured in each patch area. The results are as follows: The first patch area, which includes a clear interlayer, exhibits 91% visible transmittance, 88% transmittance at 850 nm, and 90% transmittance at 905 nm. The second patch area, which includes a gray interlayer, has about 46% visible transmittance, about 64% transmittance at 850 nm, and about 65% transmittance at 905 nm.

[0083] The LIDAR sensor area works with any patch interlayer that provides a transmittance level of at least 90% at 905 nm. Therefore, using a transparent interlayer provides the required visible light transmittance level. A different sensor, such as a rain sensor, works with any patch interlayer that provides a range of transmittance from at least 16% to approximately 85% at 850-880 nm. Therefore, using a pigmented or colored interlayer, such as a gray interlayer, effectively provides the required visible light transmittance. A transparent interlayer patch cannot be used for both sensor areas because the visible light transmittance of the transparent interlayer is too high for the rain sensor to function.

[0084] Example 2 A second panel can be constructed in the same manner as the panel in Example 1, using 2.3 mm ultra-clear glass, a solar-absorbing interlayer, and a clear patch and a second, different-colored patch in the two sensor areas. The first patch area, including the clear interlayer, exhibits approximately 91% visible transmittance, 88% transmittance at 850 nm, and 90% transmittance at 905 nm. The second patch area, including a blue-green patch (Saflex® RB47 377300 PVB interlayer, commercially available from Eastman Chemical Company), has approximately 74% visible transmittance, 78% transmittance at 850 nm, and 77% transmittance at 905 nm.

[0085] As noted above, the LIDAR sensor area works with any patch interlayer that provides a transmittance level of at least 90% at 905 nm. Therefore, using a transparent interlayer provides the required visible light transmittance level. A different sensor, such as a rain sensor, works with any patch interlayer that provides a range of transmittance from at least 16% to approximately 85% at 850-880 nm. Therefore, using a pigmented or colored interlayer, such as a blue-green interlayer, effectively provides the required visible light transmittance. A transparent interlayer patch cannot be used for both sensor areas because the visible light transmittance of the transparent interlayer is too high for the rain sensor to function.

[0086] Example 3 A multilayer glass panel can be fabricated that includes two glass substrates and a polymer interlayer. The glass substrates can include 2.3 mm thick, ultra-clear glass with very low iron content (such as commercially available Starphire® glass sold by Vitro). The polymer interlayer used in the glass panel has solar radiation functionality (commercially available from Eastman Chemical Company as Saflex® QXH1 0000S5 interlayer), which, when laminated, provides solar radiation functionality of approximately 74.9% visible transmittance, 17.1% transmittance at 850 nm, and 13.6% transmittance at 905 nm. Prior to lamination, an area of ​​the polymer interlayer is cut out, and a patch is inserted in the area where multiple sensors can be placed. The patch is a transparent polymer interlayer without solar radiation functionality (commercially available from Eastman Chemical Company as Saflex® Clear PVB interlayer). Instead of a second patch, a coating can be applied to one of the glass layers to reduce the transmittance level to approximately 80% at 850 nm. The coating can be applied to any of the four interfaces, although the outermost surface (the surface farthest from the sensor) may be deemed the least effective. Visible light transmittance is then measured in each area (i.e., where the patch was applied and where the coating was applied). The results are as follows: The patch area containing the transparent interlayer exhibits approximately 91% visible transmittance, 88% transmittance at 850 nm, and 90% transmittance at 905 nm. The patch area containing the transparent interlayer, combined with the coated glass area (where a second sensor, such as a rain sensor, may be located), has approximately 75% visible transmittance, 75% transmittance at 850 nm, and 80% transmittance at 905 nm.

[0087] As noted above, the LIDAR sensor area will function with any patch interlayer that provides a transmittance level of at least 90% at 905 nm. Therefore, using a transparent interlayer provides the required visible light transmittance level. As long as the optically transparent area has a visible light transmittance in the appropriate range (at least 16% to approximately 85% at 850-880 nm), a different sensor, such as a rain sensor, will function. By providing a coating on one or more layers of the panel (such as on one of the glass substrates, or directly on the interlayer), the visible light transmittance can be reduced to the appropriate and required level. A transparent interlayer patch cannot be used for both sensor areas without modifying the rain sensor (or other sensor) area, because the rain sensor will not function if the transparent interlayer's visible light transmittance is too high.

[0088] Comparative Example 1 A comparative example of a multilayer glass panel can be fabricated in the same manner as described above. The glass substrate includes a 2.3 mm thick, ultra-clear glass with a very low iron content (such as commercially available Starphire® glass sold by Vitro). The polymer interlayer used in the glass panel has solar radiation capabilities (commercially available from Eastman Chemical Company as Saflex® QXH1 0000S5 interlayer), which, when laminated, provides solar radiation capabilities of approximately 74.9% visible transmittance, 17.1% transmittance at 850 nm, and 13.6% transmittance at 905 nm. Only one patch is used in one sensor area (e.g., the area where a LIDAR sensor or other sensor requiring high visible light transmittance will be located). The solar interlayer material is not cut out in the second sensor area. Prior to lamination, one area of ​​the polymer interlayer is cut out, and a patch is inserted where the sensor will be located, but no patch is inserted where the second sensor (i.e., a rain sensor) will be located. The patch is a transparent polymer interlayer (Saflex® Clear PVB interlayer, available from Eastman Chemical Company) with no solar radiation functionality. In the area of ​​the second sensor where the solar-absorbing interlayer is located, the original visible light transmittance level is 17% at 850 nm, which is just appropriate for use with certain sensors, such as rain sensors. Rain sensors require a visible light transmittance of greater than 16% at 850 nm to operate. The laminate is then exposed to light, and the transmittance of the solar-absorbing interlayer at 850 nm decreases from 17% to 12% after 3,000 hours of accelerated xenon arc exposure testing (this is a similar level of solar radiation to that received by a windshield exposed to sunlight for two years). The original 17% visible light transmittance at 850 nm before exposure is just adequate to enable rain sensor function, but a visible light transmittance of 12% at 850 nm after exposure to sunlight (or UV light) renders the rain sensor inoperable.

[0089] In conclusion, laminated glass, such as an automobile windshield, that includes either multiple patches of different materials, or one or more patches and a pattern or coating on the glass in the sensor area, has enhanced sensor compatibility. Other advantages will be readily apparent to those skilled in the art.

[0090] While the present invention has been disclosed in conjunction with descriptions of specific embodiments, including what are currently considered to be preferred embodiments, the detailed description is intended to be illustrative and should not be construed as limiting the scope of the disclosure. Those skilled in the art will appreciate that the present invention encompasses embodiments other than those specifically described herein. Modifications and variations of the described embodiments can be made without departing from the spirit and scope of the present invention.

[0091] Furthermore, it will be understood that any range, value, or property recited for any single component of this disclosure may be used interchangeably, where compatible, with any range, value, or property recited for any other component of this disclosure to form embodiments having the defined values ​​for each of the components as provided throughout this specification. For example, an intermediate layer may be formed that includes poly(vinyl butyral) having any of the given ranges of residual hydroxyl content in addition to including a plasticizer in any of the given ranges to form many variations that are within the scope of this disclosure, but which would be cumbersome to list. Furthermore, ranges provided for a genus or category, such as phthalate or benzoate, may also apply to species within that genus or category, such as dioctyl terephthalate, unless otherwise noted.

Claims

1. 1. A multi-layer panel comprising: a first rigid substrate; a first polymer interlayer; and a second rigid substrate; the multi-layer panel having sensor areas for at least a first sensor and a second sensor; the first polymer interlayer has a solar absorption capability with a first visible light transmittance; the first sensor region includes a second polymer interlayer selected to provide a first optically transparent region in the first sensor region; the first optically transparent region has a second light transmittance selected to allow operation of a first sensor; the second sensor region includes a third polymer interlayer selected to provide a second optically transparent region in the second sensor region, the second optically transparent region having a third light transmittance selected to allow a second sensor to operate; the first polymer interlayer, the second polymer interlayer, and the third polymer interlayer are different; The multi-layer panel.

2. the first polymer interlayer having a solar absorption capability with a first light transmittance of less than 90% at about 905 nm; the first sensor region includes a second polymer interlayer selected to enable a first optically transparent region in the first sensor region; the first optically transparent region has a second light transmittance of greater than 90% at about 905 nm; the second sensor region includes a third polymer interlayer selected to enable a second optically transparent region in the second sensor region, the second optically transparent region having a third optical transmittance greater than about 16% and less than about 85% at about 850 nm; The multi-layer panel of claim 1 .

3. 3. The multi-layer panel of claim 1 or claim 2, wherein the second polymer interlayer is a transparent polymer interlayer.

4. The multilayer panel of any one of claims 1 to 3, wherein the third polymer interlayer is a pigmented polymer interlayer.

5. 5. The multi-layer panel of claim 4, wherein the third polymer interlayer is a colored polymer interlayer having a color that is green, blue, gray, bronze, or a combination of green, blue, gray, and bronze.

6. the first polymer interlayer has a solar absorption capability with a first visible light transmittance of less than 90% at about 905 nm; the first optically transparent region has a second light transmittance of greater than 90% at about 905 nm; the second sensor region includes a coating on at least one of the first rigid substrate, the second rigid substrate, and / or the second polymer interlayer selected to enable a second optically transparent region in the second sensor region, the second optically transparent region having a third optical transmittance greater than about 16% and less than about 85% at about 850 nm; The multilayer panel of claim 1 .

7. the multi-layer panel having a sensor area for at least a first sensor and a second sensor; the first polymer interlayer has a solar absorption capability with a first visible light transmittance of less than 90% at about 905 nm; the first sensor region includes a second polymer interlayer selected to enable a first optically transparent region in the first sensor region; the first optically transparent region has a second visible light transmittance of greater than 90% at about 905 nm; the second sensor region includes a pattern on at least one of the first rigid substrate, the second rigid substrate, and / or the second polymer interlayer selected to enable a second optically transparent region in the second sensor region, the second optically transparent region having a third visible light transmittance greater than about 16% and less than about 85% at about 850 nm; The multilayer panel of claim 1 .

8. 8. The multi-layer panel of claim 1, wherein the first and second rigid substrates are low iron or extra clear glass.

9. The multilayer panel according to any one of claims 1 to 8, wherein the multilayer panel is a windshield.

10. 1. A method of making a multi-layer panel, comprising: providing a first rigid substrate; providing a first polymer interlayer and disposing the first polymer interlayer on the first rigid substrate; providing a second rigid substrate; the first polymer interlayer has a sensor region having a first sensor region and a second sensor region, the first polymer region having a solar absorption capability with a first visible light transmittance of less than 90% at about 905 nm, the first sensor region including a second polymer interlayer selected to enable a first optically transparent region in the first sensor region, the first optically transparent region having a second visible light transmittance of greater than 90% at about 905 nm, the second sensor region including a third polymer interlayer selected to enable a second optically transparent region in the second sensor region, the second optically transparent region having a third visible light transmittance of greater than about 16% and less than about 85% at about 850 nm; the first polymer interlayer, the second polymer interlayer, and the third polymer interlayer are different; The method.

11. The method of claim 10 , wherein the second polymer interlayer is a transparent polymer interlayer.

12. 12. The method of claim 10 or claim 11, wherein the third polymer interlayer is a pigmented polymer interlayer.

13. 13. The method of claim 12, wherein the third polymer interlayer is a colored polymer interlayer having a color that is green, blue, gray, bronze, or a combination of green, blue, gray, and bronze.

14. 1. A method of making a multi-layer panel, comprising: providing a first rigid substrate; providing a first polymer interlayer and disposing the first polymer interlayer on the first rigid substrate; providing a second rigid substrate; the first polymer interlayer has a sensor region having a first sensor region and a second sensor region, the first polymer region having a solar absorption capability with a first visible light transmittance of less than 90% at about 905 nm, the first sensor region including a second polymer interlayer selected to enable a first optically transparent region in the first sensor region, the first optically transparent region having a second visible light transmittance of greater than 90% at about 905 nm, the second sensor region comprising a pattern on at least one of the first rigid substrate, the second rigid substrate, and / or the second polymer interlayer selected to enable a second optically transparent region in the second sensor region, the second optically transparent region having a third visible light transmittance of greater than about 16% and less than about 85% at about 850 nm, and the first polymer interlayer and the second polymer interlayer are different; The method.

15. 1. A method of making a multi-layer panel, comprising: providing a first rigid substrate; providing a first polymer interlayer and disposing the first polymer interlayer on the first rigid substrate; providing a second rigid substrate; the first polymer interlayer has a sensor region having a first sensor region and a second sensor region, the first polymer region having a solar absorption capability with a first visible light transmittance of less than 90% at about 905 nm, the first sensor region including a second polymer interlayer selected to enable a first optically transparent region in the first sensor region, the first optically transparent region having a second visible light transmittance of greater than 90% at about 905 nm, the second sensor region comprising a coating on at least one of the first rigid substrate, the second rigid substrate, and / or the second polymer interlayer selected to enable a second optically transparent region in the second sensor region, the second optically transparent region having a third visible light transmittance of greater than about 16% and less than about 85% at about 850 nm, and the first polymer interlayer and the second polymer interlayer are different; The method.

16. The method of any of claims 10 to 15, wherein the first and second rigid substrates are low iron or extra clear glass.

17. The method of any one of claims 10 to 16, wherein the multi-layer panel is a windshield.

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