Polymer coating layers for use with holographic optical elements

Abstract

To provide tie layers and structures that exhibit superior properties and that provide desirable optical properties when incorporated into laminates, such as windshields, windows or other glazings containing holographic optical elements (HOE).SOLUTION: A laminated structure has partitioned low refractive index compound levels within a polymeric volume hologram such that light modification properties of the polymeric volume hologram following lamination and low refractive index compound equilibration with the tie layer are greater than 70% of the magnitude of the original light modification properties of the polymeric hologram prior to assembly, in at least one wavelength range.SELECTED DRAWING: Figure 7

Description

Technical Field

[0001]

[0001] The present invention generally relates to layers such as polymer coatings or bonding layers used to encapsulate and protect holographic optical elements, and to laminates including these intermediate layers. More particularly, the present invention generally relates to a polymer coating or bonding layer, and to a laminate including at least one layer including the polymer coating or bonding layer and a holographic optical element.

Background Art

[0002]

[0002] Generally, a multilayer glass panel includes a laminate composed of an intermediate layer or a multilayer intermediate layer or an intermediate layer sandwiched between two glass plates. In some applications, the laminate may include only one glass plate or other rigid substrate. Laminated multilayer glass panels are generally used for architectural window applications, in transportation vehicles (including automobiles, trucks, trains, boats, airplanes), and in solar power generation solar panels. Multilayer glass panels used in the first two applications are generally called laminated safety glass. Typically, the main functions of the intermediate layer in laminated safety glass are to absorb the energy resulting from an impact or force applied to the glass, to hold the layers of glass together even when a force is applied, and to prevent the glass from shattering into sharp fragments if the glass is broken. In addition to these safety advantages, the intermediate layer can additionally impart a higher sound insulation rating to the laminated glass, reduce UV and IR transmission, and / or improve the aesthetic appearance of the associated window.

[0003]

[0003] Typically, an interlayer for use in laminated glass applications is generally manufactured by mixing a polymer resin such as poly(vinyl acetal) with one or more plasticizers and melt-processing the mixture by any suitable process or method known to those skilled in the art to form the interlayer. After formation, these interlayers, or multilayer interlayers, are typically wound onto rolls for storage prior to later use in a multilayer glass panel. Coating or bonding layers can be manufactured in the same manner, or by using mixing methods and equipment known in the art, to mix the materials together and then coat or form the bonding layer or coating.

[0004]

[0004] The interlayer can be incorporated into the multilayer glass panel using various techniques known in the art. For example, at least one interlayer can be placed between two substrates, and excess interlayer can be trimmed from the edges, thereby creating an assembly. It is not uncommon for multiple interlayers to be placed within or between two substrates, thereby creating a multilayer stack having an outer glass panel and multiple internal polymer interlayers. Once formed, these stacks are typically processed to remove most of the interfacial air by any suitable process or method known to those skilled in the art, such as by means of nip rollers, vacuum bags, vacuum rings, or another suitable degassing mechanism. In addition, the interlayer can be partially crimped to the substrate by any method known to those skilled in the art. In a final step, the interfacial bonds generated during the degassing operation are typically made more durable by a lamination process at elevated temperature and / or pressure, some of which are processes known to those skilled in the art such as autoclave treatment, but are not limited thereto.

[0005]

[0005] In other embodiments, thinner layers such as coating or bonding layers may be used alone or in combination with other layers. The coating or bonding layer may be used as an adhesive to bond a substrate layer, such as a protective layer, to another layer. A variety of different materials can be used as the substrate layer in laminated safety glass, but polyethylene terephthalate (PET) is known for use as a plastic layer in laminated glass. Other materials include polyethylene naphthalate (PEN), polycarbonate, polyamide, polyimide, cellulose ester, polyester, and the like. The substrate layer may have an adhesive applied to one or both of its sides. In order to reduce optical distortions from variations in the thickness of the adhesive and the use of thicker layers such as polymer intermediate layers, it may be desirable to use thinner layers such as coating or bonding layers. Further, the thinner layer of adhesive allows the plastic layer to follow more closely the contour of the curved glass in a particular glass laminate, reducing or eliminating bending or wrinkling of the plastic layer or adhesive layer during the lamination process, as well as reducing or eliminating waviness or the applesauce effect of the plastic sheet, and reducing or eliminating wrinkles. To assist with the problem of air removal in the laminate, the coating or bonding layer may be embossed or surface imprinted thereon to allow air to flow out of the laminate.

[0006]

[0006] Higher performance laminates such as front glass are emerging that require additional functionality such as a head-up display (HUD). The polymer layers must not interfere with the optical properties of the glass laminates in which they are incorporated. Additional materials are thought to provide the required additional functionality.

[0007]

[0007] Recent developments in materials, machine tools, and patterning have enabled holography to transition from novelty products to high-tech applications. One such possible application is the use of holographic elements or holographic optical elements (HOEs) as angular-selective reflective elements that enable automotive HUD technology. Holography is now advancing more and more rapidly in the last decade, with the use of holographic elements proposed for applications such as fixed displays, automotive HUD applications, and user head-mounted glasses / displays. In all of these cases, a reasonable device configuration has been assumed, along with an understanding of the type and pattern of the holographic element structure required to produce the desired optical effect. However, in most cases, these technologies are still in the initial stages of scaling up, and organizations are working to manufacture prototypes that meet the usage compliance criteria.

[0008]

[0008] One such example of early-stage development efforts is the use of holography in automotive head-up display applications. The use of holographic technology using HOEs embedded in the windshield or windscreen that reflect light from a dash-mounted projector has been proposed. The embedded HOE is designed to reflect light from a very narrow set of angles while allowing light from most other angles to pass through; as a result, what is obtained is a windshield system that reflects incident light from an in-dash projector system while not blocking the passage of light from all other angles. This enables the driver to simultaneously see what is happening outside the vehicle and also perceive the information image projected from the dash.

[0009]

[0009] Early adopters in this field have successfully designed and manufactured prototype HOE films that can demonstrate the ability to both reflect angle-targeted incident light while maintaining the ability to transmit light at other angles through the film. However, when incorporating these films into a finished windshield, there are significant challenges in maintaining the desired optical properties. The lamination of HOE films into the final laminated glass construction invariably results in unintended material changes that affect the quality and intensity of light reflected by the HOE. More specifically, many of the combinations of commercially available interlayers and HOE films result in deficiencies in terms of processability and / or functionality.

[0010]

[0010] The majority of the HOE failures mentioned above are caused by the HOE used to make the final part, such as the windshield. This can lead to materials and processes that are difficult to apply. Attempts to laminate the HOE directly to or with traditional interlayer films such as PVB and polyurethane (TPU) interlayers result in significant reductions in the intensity of the reflective response, typically on the order of 50-90%, although other reductions are possible. Isolating or protecting the HOE from the polymer interlayer by capping it with a rigid surface with limited permeability helps preserve the intensity of the response, but has cost implications and can also have the unintended consequence of causing wrinkling and mottling of the HOE film at a level that reduces the quality of the reflective response (changes in reflected magnitude). Lamination quality can also be degraded with the addition of a rigid polymer substrate cap layer, as evidenced by bake tests and / or visible air trapped around the outer edges of the HOE.

[0011]

[0011] Commercially available HOE films are composed of various materials. In most cases, these films include a specially formulated elastic photosensitive polymer film coated on a rigid substrate. In the final reflective film, the HOE is patterned for the desired optical effect by using high-intensity light (such as one or multiple lasers) to drive a chemical reaction that creates carefully designed regions of low and high refractive indices within the elastic photosensitive polymer film. Low refractive index compounds (LRICs) (or multiple LRICs) are also often incorporated into the photosensitive polymer layer to increase the refractive index difference within the patterned structure and enhance the intensity of the HOE response.

[0012]

[0012] LRICs are typically short-chain molecules that are mobile in most polymer films and are typically at least partially miscible. Lamination of a HOE containing such LRICs to a polymer film without LRICs typically creates a concentration gradient that feeds these LRIC moieties into the laminated film, which typically results in an unacceptable reduction in HOE reflection intensity. The final concentration levels in both the initial HOE and the adjacent encapsulation layer depend primarily on (1) the relative solubility of the LRIC in each layer, and (2) the relative thickness of each layer. Temperature, degree of contact, and time may also play a role in determining the final concentration levels.

[0013]

[0013] The miscibility of LRIC in encapsulation films, coatings or layers, such as PVB or TPU, typically used in glass laminates, results in a net movement of these LRIC out of the original HOE film and into adjacent films or layers. This loss reduces the refractive index gradient within the HOE film, resulting in lower reflection intensity. Capping of the HOE film with a rigid crystal or highly aligned surface plate prevents LRIC movement and mitigates this problem, while such capping has often been shown to introduce other problems such as cost, wrinkling of the HOE film and a tendency to form bubbles. There is a clear need for an HOE film encapsulation system that prevents wrinkling, bubble formation, and unacceptable loss of LRIC from the HOE film.

[0014]

[0014] Accordingly, there is a need for a coating or bonding layer for use as an encapsulation film in a laminate that can provide the desired performance expected of conventional glass laminates, while at the same time minimizing cost and not degrading the optical and physical properties of the HOE (or HOE film) incorporated into the laminate.

Summary of the Invention

[0015]

[0015] The present invention generally relates to bonding layers and structures that exhibit excellent properties and provide desirable properties when incorporated into laminates such as front glass, windows or other sheet glass containing a holographic optical element (HOE). The bonding layer, when connected to the HOE film and optionally an additional polymer layer for use in a laminate, maintains the properties of the HOE film and does not impair them.

[0016]

[0016] Embodiments of the present invention are described herein in connection with the following figures.

Brief Description of the Drawings

[0017]

Figure 1

Figure 2

[0018] FIG. is a cross-sectional view showing another embodiment of a glass laminate containing a HOE film encapsulated between two intermediate layers and having an adhesive or bonding layer between the HOE film and the intermediate layer.

Figure 3

[0019] FIG. is another cross-sectional view showing another embodiment of a glass laminate containing a HOE film, showing a holographic element and a holographic element substrate encapsulated between two intermediate layers.

Figure 4

[0020] FIG. is a cross-sectional view showing another embodiment of a glass laminate containing a HOE film, showing a holographic element and a holographic element substrate encapsulated between two intermediate layers, with a protective element substrate and a protective element bonding layer adjacent to the HOE film.

Figure 5

[0021] FIG. is a cross-sectional view showing another embodiment of a glass laminate containing a HOE film, showing a holographic element and a holographic element substrate encapsulated between two intermediate layers, with the protective element substrate encapsulated by two protective element bonding layers adjacent to the HOE film.

Figure 6

[0022] FIG. is a cross-sectional view showing another embodiment of a glass laminate containing a HOE film, showing a holographic element and a holographic element substrate encapsulated between one intermediate layer and a protective element substrate encapsulated by two protective element bonding layers adjacent to the HOE film.

Figure 7

[0023] FIG. represents a cross-sectional view of another embodiment of a glass laminate having only one glass or rigid layer and containing a HOE film, showing a holographic element and a holographic element substrate protected by a coating or bonding layer.

Figure 8

[0024] A cross-sectional view of another embodiment of a glass laminate having only one glass or rigid layer and containing an HOE film, showing a holographic element and a holographic element substrate protected by a protective element substrate encapsulated by two protective element bonding layers adjacent to the HOE film.

DETAILED DESCRIPTION OF THE INVENTION

[0018]

[0025] The present invention generally relates to bonding layers and structures that exhibit excellent properties and provide desirable optical properties when incorporated into laminates such as front glass, windows, or other sheet glass containing holographic optical elements (HOEs). The bonding layer, when connected to an HOE film and optionally an additional polymer layer for use in a laminate, maintains the properties of the HOE film and does not impair them. More particularly, the present invention generally relates to the use of a coating or bonding layer containing LRIC and a bonding layer in a laminate comprising at least one HOE film. The present invention also relates to a multilayer intermediate layer or sheet comprising a polymer layer or intermediate layer and an HOE film, wherein the polymer layer and the HOE film are in direct contact and the multilayer intermediate layer can be incorporated into a laminate. As will be described in more detail below, the coatings and bonding layers are formulated and selected to be used with an HOE film and to form a laminate having an HOE film incorporated therein as well. The coatings and bonding layers described herein can provide desirable properties to the laminate while maintaining the desired optical properties required for such a laminate.

[0019]

[0026] The coatings and bonding layers can be successfully formulated with one or more LRICs, so that the HOE film is such that the final distribution level maintains HOE effectiveness (i.e., the effectiveness and strength of the HOE are not significantly reduced), the bonding layer and It has been discovered that it can be combined with an optional intermediate layer. One or more LRICs in the bonding layer may be the same as or different from the LRICs in the HOE. In addition, the chemical and physical properties of these bonding layers can be modified to further improve the characteristics.

[0020]

[0027] As used herein, the term "intermediate layer" refers to a single-layer or multi-layer polymer sheet that may be suitable for use with at least one rigid substrate to form a multi-layer panel. The terms "single sheet" and "integral" intermediate layers refer to intermediate layers formed from a single sheet, while the terms "multi-layer" and "multilayer" intermediate layers refer to intermediate layers having two or more sheets that are co-extruded, assembled, laminated, or otherwise combined with each other. As used herein, "bonding layer" refers to a layer or sheet in an intermediate layer that bonds at least two other layers together. The bonding layer may be a coating, and the terms "coating" and "bonding layer" may be used interchangeably herein. The bonding layer is generally considerably thinner than the polymer layer or intermediate layer.

[0021]

[0028] The term "multi-layer intermediate layer" refers to a polymer intermediate layer that includes at least two polymer layers. As further discussed below, the multi-layers may be any combination of separately extruded layers, co-extruded layers, or separately extruded layers co-extruded with other layers. Thus, the multi-layered intermediate layer may include, for example, two or more single-layer intermediate layers combined together ("multi-layer intermediate layer"); two or more layers co-extruded together ("co-extruded intermediate layer"); two or more co-extruded intermediate layers combined together; a combination of at least one single-layer intermediate layer and at least one co-extruded intermediate layer; and a combination of at least one multi-layer intermediate layer and at least one co-extruded intermediate layer.

[0022]

[0029] As used herein, a holographic optical element (HOE) refers to a holographic configuration that includes at least one substrate referred to as a holographic element substrate and a holographic element or film such as a volume hologram or a polymeric volume hologram. The terms holographic optical element and holographic element may be used interchangeably. A HOE film is a polymeric film that uses holographic technology to change the way light travels through a medium and typically creates a specular surface that is translucent, reflects light at certain set angles, and does not reflect light at other angles.

[0023]

[0030] The bonding layer may be used alone or, together with another film such as a HOE film, as an encapsulation layer that provides functional support such as coating, adhesion, and protection to the HOE film. Depending on the desired application and properties, more than one encapsulation layer and film may be used. For example, two intermediate layers may be used (on both sides) to encapsulate the HOE film. In an embodiment, one bonding layer may include LRIC, while the second bonding layer may be a conventional bonding layer that does not include LRIC. In other embodiments, both (or all) bonding layers may include LRIC.

[0024]

[0031] As described above, the coating or bonding layer can be used with an optional polymer layer to form multilayer intermediate layers and laminates such as windshield glass or other laminated glass panels that are useful for many applications. In various embodiments, these polymer layers can be formed from thermoplastic resins such as ethylene vinyl acetate, thermoplastic polyurethane, ionomer, poly(vinyl acetal), and mixtures thereof. Various arrangements and types of polymer layers are described in detail below.

[0025]

[0032] The use of certain polymer bonding layers in combination with HOE can provide beneficial properties to the glass laminate. When a HOE layer is included, depending on the combination of layers and structures, a plasticizer can be distributed or migrated to or from the HOE layer, which can change the layer thickness and properties of the HOE layer. Therefore, certain specially formulated types of intermediate layers may be preferred. The plasticizer distribution can also change the properties of the polymer layer. The plasticizer distribution can also change the properties of the polymer layer.

[0026]

[0033] Generally, the bonding layer (and optional polymer layer) can contain at least 1, at least 2, at least 3, at least 4, at least 5, at least 10, at least 15, at least 20, at least 25, at least 30, at least 35, at least 40, at least 45, at least 50, at least 55, at least 60, at least 65, at least 70, at least 75, at least 80, at least 85, at least 90, at least 95, or at least 99 weight percent of one or more thermoplastic resins, based on the total weight of the layer. Additionally or alternatively, the layer can contain 99 or less, 95 or less, 90 or less, 80 or less, 70 or less, 60 or less, or 50 weight percent or less of one or more thermoplastic resins, based on the total weight of the layer, although other amounts can be used if desired. The types of layers and thermoplastic resins that can be used to manufacture such layers are further described below.

[0027]

[0034] In various embodiments, the bonding layer and the HOE layer may be in direct contact with each other or may be disposed adjacent to each other indirectly through another layer. In one or more embodiments, at least one polymer layer and at least one HOE layer are in direct contact with each other when forming an intermediate layer or laminate. In such embodiments, the bonding layer and the HOE layer desirably bond directly to each other, although an adhesive may be utilized to strengthen this bond. Generally, this bond can be a bond formed when the layers are stacked on top of each other and the multilayer intermediate layer is heated above the glass transition temperature of all the layers. This can occur, for example, by stacking the layers on top of each other, using heat and / or pressure, or by coextruding the layers, or a combination of both.

[0028]

[0035] In various embodiments, the optional polymer layers described herein may include at least two polymer layers (e.g., single layers or coextruded multilayers) disposed in direct contact with each other. When more than three layers are utilized in the multilayer intermediate layer, some of the layers may be referred to as skin layers and one or more of the layers may be referred to as core layers. As used herein, a "skin layer" generally refers to the outer layer of the intermediate layer, and "one or more core layers" generally refers to one or more inner layers disposed between the skin layers. At least one surface of the core layer may be in direct contact with at least one surface of the skin layer or may be in indirect contact with the skin layer through a bonding layer, coating or adhesive.

[0029]

[0036] Exemplary layer configurations in embodiments of the multilayer intermediate layer include: skin / core / skin, skin / core, skin / core / core / skin, and skin / core / core / core / skin, and as will be known to those skilled in the art, other embodiments are possible as well.

[0030]

[0037] FIG. 1 depicts an exemplary laminate 10 that includes a HOE film layer 12 and two polymer layers 14 that form a multilayer intermediate layer 16. As shown in FIG. 1, the complete intermediate layer structure 16 is interposed between two rigid substrates 18 such as glass.

[0031]

[0038] FIG. 2 depicts an exemplary laminate 10 including a HOE layer 12, two polymer layers 14, and two bonding layers 20 that form a multilayer intermediate layer 16. As shown in FIG. 2, the intermediate layer 16 is interposed between two rigid substrates 18 such as glass.

[0032]

[0039] The multilayer intermediate layers described herein may also have more than three layers (e.g., at least 4, at least 5, at least 6, or up to 10 or more individual layers). In various embodiments, the multilayer intermediate layer structure can contain two, three, four, or more polymer layers, two or more of which can be in direct contact with each other, with the HOE layer and / or other types of layers. The layers can have various thicknesses, which is mainly determined by the type of intermediate layer or laminate in which the layer is used and can be any desired thickness.

[0033]

[0040] In various embodiments, the thickness or gauge of any layer or intermediate layer can be at least about 0.5 mil, at least about 1, 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 15, at least about 20, at least about 25, at least about 30, at least about 35, at least about 40, at least about 45, at least about 50, at least about 55, at least about 60 mils or more, depending on the desired properties and applications. In millimeters, the thickness of the polymer layer or intermediate layer can be at least about 0.025, at least about 0.05, at least about 0.075, at least about 0.10, at least about 0.125, at least about 0.150, at least about 0.175, at least about 0.20, at least about 0.225, at least about 0.25, at least about 0.38, at least about 0.51, at least about 0.64, at least about 0.76, at least about 0.89, at least about 1.02, at least about 1.15, at least about 1.28, at least about 1.52 mm or more.

[0034]

[0041] The bonding layer and optional polymer layer described herein may further comprise at least one plasticizer. Depending on the specific composition of the thermoplastic resin forming the polymer layer, the plasticizer may be present in an amount of at least 0.45 kg (1 pound), at least 0.91 kg (2 pounds), at least 1.36 kg (3 pounds), at least 1.81 kg (4 pounds), at least 2.27 kg (5 pounds), at least 4.54 kg (10 pounds), at least 6.80 kg (15 pounds), at least 9.07 kg (20 pounds), at least 11.3 kg (25 pounds), at least 13.6 kg (30 pounds), at least 15.9 kg (35 pounds), at least 18.1 kg (40 pounds), at least 20.4 kg (45 pounds), at least 22.7 kg (50 pounds), at least 24.9 kg (55 pounds), at least 27.2 kg (60 pounds) or more per 45.3 kg (100 pounds) of resin. In embodiments, the amount of plasticizer may be 120 or less, 110 or less, 105 or less, 100 or less, 95 or less, 90 or less, 85 or less, 80 or less, 75 or less, 70 or less, 65 or less, 60 or less, 55 or less, 50 or less, 45 or less, or 40 phr or less, although other amounts may be used depending on the specific materials and desired properties.

[0035]

[0042] In various embodiments, the bonding layer and optional intermediate layer can contain at least one plasticizer in an amount of at least 2, at least 5, at least 8, at least 10, at least 13, at least 15, at least 18, or at least 20 weight percent or more based on the weight of the layer. Additionally or alternatively, the polymer can contain at least one plasticizer in an amount of up to 100, up to 80, up to 70, up to 60, up to 50, up to 40, up to 30, up to 25, or up to 20 weight percent based on the weight of the polymer layer.

[0036]

[0043] Low refractive index compounds or plasticizers useful for the bonding layer and the polymer layer include plasticizers that have a low refractive index and are compatible with other materials such as materials in the HOE film layer. Low refractive index compounds are often referred to as plasticizers in this specification, but other compounds with a low refractive index that assist in adjusting the refractive index and cannot be called "plasticizers" may also be used. Examples include, but are not limited to, LRICs such as fluorourethanes (or fluorinated urethanes) and fluorinated esters. Fluorourethanes can be obtained, for example, by reacting isocyanates with fluorinated alcohols. An example of a useful LRIC can be the fluorourethane disclosed in U.S. Patent No. 8,999,608 B2, the disclosure of which is incorporated herein by reference. In embodiments, the LRIC has a refractive index of less than about 1.45, or less than about 1.40, or less than about 1.35, or less than about 1.30, or less than about 1.25. In embodiments, an LRIC having the lowest possible refractive index is desired.

[0037]

[0044] In some embodiments, the polymer intermediate layer and the polymer volume hologram have similar physical properties such that the plasticizer distribution between the layers is similar and the amount of plasticizer in the coating or bonding layer is an amount within the range of -25 to +25 weight percent of the concentration of plasticizer in the polymer volume hologram. In embodiments, the polymer intermediate layer includes a concentration of plasticizer within the range of -15 to +15 weight percent, or -10 to +10 weight percent, -5 to +5 weight percent of the concentration of plasticizer in the original polymer volume hologram.

[0038]

[0045] In other embodiments where the coating or bonding layer and the polymer volume hologram have different physical properties such that the plasticizer distribution between the layers is different, the amount of plasticizer in the polymer intermediate layer may be less than or greater than the total amount of plasticizer in the original polymer volume hologram and should be determined through an understanding of the relative plasticizer distribution between the layers. In some embodiments, the amount of plasticizer in the polymer intermediate layer is at least 1%, 5%, 10%, 20%, 30%, 40%, 50%, 60%, 70%, 80% or at least 90 weight percent of the concentration of plasticizer in the polymer volume hologram. In other embodiments, the plasticizer in the polymer intermediate layer is at least 101%, 110%, 120%, 130%, 140%, 150%, 200%, 300%, 400% or at least 500 weight percent or more of the concentration of plasticizer in the polymer volume hologram.

[0039]

[0046] In most embodiments, the coating or bonding layer is formulated to minimize the uptake of plasticizer such that the plasticizer level in the fully encapsulated polymer volume hologram is at least 70%, or at least 80%, or at least 90% of the starting level of plasticizer present in the original unlaminated or unencapsulated polymer volume hologram.

[0040]

[0047] In embodiments, the coating or bonding layer comprises a plasticizer or plasticizer blend selected such that the plasticizer or plasticizer blend has a refractive index within the range of -0.1 to +0.1 of the refractive index of the plasticizer or plasticizer blend in the original polymer volume hologram. In embodiments, the plasticizer or plasticizer blend is selected to have a refractive index within the range of -0.05 to +0.05, or within the range of -0.02 to +0.02 of the refractive index of the plasticizer or plasticizer blend in the original polymer volume hologram.

[0041]

[0048] As long as the use of the plasticizer does not adversely affect the desired properties of the final part, or cause the final properties of the laminate or other device incorporating the polymer layer and the HOE to fall outside the desired performance range, additional plasticizers may be used, specifically not adjacent to or in contact with the HOE in the coating or bonding layer, and may be used in the coating or bonding layer. The plasticizer can be any one known in the art. The plasticizer can be either a monomer or a polymer structure. In various embodiments, the plasticizer can be a compound having a hydrocarbon segment of 30 or fewer, 25 or fewer, 20 or fewer, 15 or fewer, 12 or fewer, or 10 or fewer carbon atoms and at least 6 carbon atoms. Suitable conventional plasticizers for use in these intermediate layers include, for example, esters of polybasic acids or polyhydric alcohols, among others. Suitable plasticizers include, for example, triethylene glycol di-(2-ethylhexanoate) ("3GEH"), triethylene glycol di-(2-ethylbutyrate), triethylene glycol diheptanoate, tetraethylene glycol diheptanoate, dihexyl adipate, dioctyl adipate, hexyl cyclohexyl adipate, diisononyl adipate, heptyl nonyl adipate, dibutyl sebacate, butyl ricinoleate, castor oil, dibutoxyethyl phthalate, diethyl phthalate, dibutyl phthalate, trioctyl phosphate, triethylene glycol ester of coconut fatty acid, phenyl ether of polyethylene oxide rodine derivative, oil-modified alkyd resin of sebacic acid, tricresyl phosphate, and mixtures thereof. In a particular embodiment the plasticizer is 3GEH.

[0042]

[0049] In addition, other plasticizers such as high refractive index plasticizers may also be used either alone or in combination with another plasticizer, particularly in layers that are not adjacent to or in contact with the HOE. As used herein, the term "high refractive index plasticizer" refers to a plasticizer having a refractive index of at least 1.460. The high refractive index plasticizer can increase or decrease the refractive index of one or more layers and can improve the optical properties of the intermediate layer, including unevenness, haze, and / or transparency. In embodiments, suitable high RI plasticizers for use may have a refractive index of at least 1.460, at least 1.470, at least 1.480, at least 1.490, at least 1.500, at least 1.510, at least 1.520 and / or 1.600 or less, 1.575 or less, or 1.550 or less as measured as described above.

[0043]

[0050] If the coating or bonding layer contains a high RI plasticizer, the plasticizer can exist alone in the layer or can be blended with one or more additional plasticizers. Examples of types or classes of high refractive index plasticizers can include, but are not limited to, polyadipates (RI of 1.460 - 1.485); epoxides such as epoxidized soybean oil (RI of 1.460 - 1.480); phthalates and terephthalates (RI of 1.480 - 1.540); benzoates and toluates (RI of 1.480 - 1.550); and other special plasticizers (RI of 1.490 - 1.520). Specific examples of suitable RI plasticizers can include, but are not limited to, dipropylene glycol dibenzoate, tripropylene glycol dibenzoate, polypropylene glycol dibenzoate, isodecyl benzoate, 2-ethylhexyl benzoate, diethylene glycol benzoate, butoxyethyl benzoate, butoxyethoxyethyl benzoate, butoxyethoxyethoxyethyl 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, diethylene glycol di-o-toluate, triethylene glycol di-o-toluate, dipropylene glycol di-o-toluate, 1,2-octyl dibenzoate, tri-2-ethylhexyl trimellitate, di-2-ethylhexyl terephthalate, bis-phenol A bis(2-ethylhexaoate), di-(butoxyethyl) terephthalate, di-(butoxyethoxyethyl) terephthalate, and mixtures thereof. In embodiments, the high RI plasticizer can be selected from dipropylene glycol dibenzoate and tripropylene glycol dibenzoate, and / or 2,2,4-trimethyl-1,3-pentanediol dibenzoate. In various embodiments, the plasticizer can be selected from at least one of the following: benzoate, phthalate, phosphate, arylene-bis(diaryl phosphate), and isophthalate.

[0044]

[0051] Other useful plasticizers include triphenyl phosphate, tricresyl phosphate, cresyl diphenyl phosphate, octyl diphenyl phosphate, diphenyl biphenyl phosphate, trioctyl phosphate, tributyl phosphate, diethyl phthalate, dimethoxyethyl phthalate, dimethyl phthalate, dioctyl phthalate, dibutyl phthalate, di-2-ethylhexyl phthalate, butyl benzyl phthalate, dibenzyl phthalate, butyl phthalyl butyl glycolate, ethyl phthalyl ethyl glycolate, methyl phthalyl ethyl glycolate, triethyl citrate, tri-n-butyl citrate, acetyl triethyl citrate, acetyl-tri-n-butyl citrate, and acetyl-tri-n-(2-ethylhexyl) citrate.

[0045]

[0052] Mixtures of plasticizers may also be used. For example, mixtures of one or more LRICs and one or more conventional plasticizers may be used. Alternatively, two or more LRICs may be used alone or in combination with plasticizers that are not other conventional ones.

[0046]

[0053] The types of thermoplastic resins that can be used to form the coating or bonding layer, as well as additional polymer layers, are described in more detail below. EVA layer

[0054] In various embodiments, one or more of the coatings or bonding layers described herein may comprise, consist essentially of, or consist of ethylene vinyl acetate ("EVA") resin. In such embodiments, the layer may also be referred to as an "EVA layer". These materials are commercially available, for example, as EVALAYER EV070C clear EVA film (from Interlayer Solutions) and as VISTASOLAR® 520.68 film (from TPI All Seasons Co., LTD) and from other suppliers as well.

[0047]

[0055] In embodiments where at least one layer comprises EVA, the layer may comprise at least one LRIC. The EVA layer may also optionally contain other plasticizers depending on its properties and, if present, other layers. The amount of plasticizer may include any LRIC and may be in the same ranges as those previously disclosed.

[0048]

[0056] EVAs having various levels of vinyl acetate comonomer can be used depending on the desired properties. In certain embodiments, the EVA comprises a vinyl acetate content of at least 70, at least 80, or at least 90 and / or 99 or less, 98 or less, or 95 weight percent or less. In other embodiments, the vinyl acetate content may be various amounts depending on the desired use and properties, but may be less than 70 weight percent, such as at least about 10, or at least about 15, or at least about 20, or at least about 25 or more and / or about 45 or less, about 40 or less, about 35 or less, or about 20 to about 40 or about 25 to about 35 weight percent.

[0049]

[0057] In various embodiments, the EVA may include a compounded EVA that may contain a silane additive, a peroxide additive, a co - activator, a UV blocker, and / or an antioxidant. Alternatively, the EVA may include an "uncompounded" EVA lacking one or more of the components listed above that are contained in the compounded EVA, such as a peroxide additive (in which case the EVA is no longer thermally reactive). In various embodiments, the EVA may be maleated.

[0050]

[0058] The EVA layer can be used alone or in connection with other polymer layers, coatings or bonding layers described herein to produce various types of multilayer intermediate layers that may include other types of layers, such as poly(vinyl acetal) layers like a polyvinyl butyral ("PVB") layer. Exemplary embodiments of multilayer intermediate layers include, but are not limited to: EVA / HOE / EVA, PVB / EVA / HOE / EVA / PVB, PVB / HOE / EVA, and PVB / HOE / EVA / PVB.

[0051]

[0059] Although not desiring to be bound by theory, the EVA layer can also function as a bonding layer between the poly(vinyl acetal) layer and the HOE layer or film, and it is believed that it can strengthen the bond between these two layers. In such embodiments, the EVA layer can at least partially intervene between the poly(vinyl acetal) layer and the HOE layer. In other embodiments, the EVA can be a separate layer rather than a bonding layer.

[0052]

[0060] The multilayer intermediate layer containing the EVA layer and one or more other polymer layers can be manufactured using any method known in the art. For example, each layer can be separately formed using techniques known in the art and then laminated together. Alternatively, the multilayer intermediate layer containing the EVA layer and another polymer layer can be manufactured via coextrusion.

[0053]

[0061] Due to the cross-linking properties of EVA, it is generally desirable to avoid fully cross-linking the EVA when forming the EVA layer. Typically, the partially cross-linked EVA can be further coextruded with other polymer layers to form a multilayer intermediate layer. Thus, it may be desirable to utilize an extrusion temperature that does not fully cross-link the EVA. Thermoplastic polyurethane layer

[0062] In various embodiments, the coating or bonding layer described herein can comprise, consist essentially of, or consist of a thermoplastic polyurethane ("TPU") resin. In such embodiments, the polymer layer may also be referred to as a "TPU layer". One example is Product A4700NAT (commercially available from Covestro LLC - specialty film (formerly Deerfield Urethane)). In various embodiments, the TPU can include aliphatic isocyanate - polyether or polyester urethane. Additionally, in certain embodiments, the TPU can also include UV stabilizers, antioxidants, as well as other additives to provide additional stability to the TPU when exposed to heat and UV light.

[0054]

[0063] In embodiments where the coating or tie layer comprises TPU, the layer may comprise at least one LRIC. The TPU layer may also optionally contain other plasticizers, depending on its properties and other layers present if any. The amount of plasticizer may include any LRIC and may be in the same ranges as those disclosed heretofore.

[0055]

[0064] The TPU layer is used in conjunction with the HOE layer and other polymer layers described herein and can be used to fabricate various types of multilayer intermediate layers that may also include a poly(vinyl acetal) or PVB layer. Exemplary embodiments of multilayer intermediate layers include, but are not limited to: TPU / HOE / TPU, PVB / TPU / HOE / TPU / PVB, PVB / HOE / TPU and PVB / HOE / TPU / PVB.

[0056]

[0065] Without wishing to be bound by theory, the TPU layer may also function as a tie layer between the poly(vinyl acetal) layer and other layers of various materials such as HOE and the film, and it is believed that it can strengthen the bond between these two layers. In such embodiments, the TPU layer can be at least partially interposed between the poly(vinyl acetal) and the HOE layer or the film. In other embodiments, the TPU can be an individual layer rather than a tie layer.

[0057]

[0066] Multilayer intermediate layers containing a TPU layer and another polymer layer can be manufactured using any method known in the art. For example, each layer can be formed separately using techniques known in the art and then laminated together. Alternatively, multilayer intermediate layers containing a TPU layer and another polymer layer may be manufactured via coextrusion. Ionomer layer

[0067] In various embodiments, the coating or bonding layer described herein may comprise, consist essentially of, or consist of an ionomer resin. In such embodiments, the coating or bonding layer may also sometimes be referred to as an "ionomer layer."

[0058]

[0068] Generally, an ionomer resin may comprise a partially neutralized acid-ethylene copolymer. Further, the ionomer resin may have acid functional groups in the range of, for example, 0.1 to 30 weight percent, 1 to 25 weight percent, or 5 to 20 weight percent based on the total weight of the polymer. In one or more embodiments, the ionomer resin may have acid functional groups from at least 0.1, at least 1, at least 5, at least 10, at least 15 weight percent and / or up to 30 weight percent, up to 25, or up to 20 weight percent of one or more acrylic acids. Such acrylic acids may include, for example, acrylic acid, maleic acid, maleic anhydride, methacrylic acid, itaconic acid, fumaric acid, monomethyl maleic acid, and mixtures thereof.

[0059]

[0069] Further, in various embodiments, the ethylene copolymer may be selected from the group consisting of acrylates, methacrylates, and combinations thereof. In such embodiments, the methacrylate may include methyl acrylate, methyl methacrylate, butyl acrylate, butyl methacrylate, glycidyl methacrylate, vinyl acetate, and mixtures thereof. The ionomer resin is further described in U.S. Patent Nos. 8,399,097 and 8,399,098, the disclosures of which are incorporated herein by reference in their entirety.

[0060]

[0070] In embodiments where the coating or bonding layer comprises an ionomer, the layer may comprise at least one LRIC. The ionomer layer may also optionally contain other plasticizers depending on its properties and the other layers present, if any. The amount of plasticizer may include any LRIC and may be in the same ranges as those disclosed heretofore.

[0061]

[0071] The ionomer layer is used in connection with other coatings or bonding layers described herein, as well as other polymer layers and HOE layers, and various types of multilayer intermediate layers can be manufactured that may also include a poly(vinyl acetal) layer. Exemplary embodiments of the multilayer intermediate layer include, but are not limited to: ionomer / HOE / ionomer, PVB / ionomer / HOE / ionomer / PVB, PVB / HOE / ionomer, and PVB / HOE / ionomer / PVB.

[0062]

[0072] Multilayer intermediate layers containing an ionomer layer and another coating or bonding layer can be manufactured using any method known in the art. For example, each layer can be formed separately using techniques known in the art and then laminated together. Alternatively, multilayer intermediate layers containing an ionomer layer and another polymer layer can be manufactured via coextrusion. Poly(vinyl acetal) layer

[0073] In various embodiments, the coatings or bonding layers described herein can include, consist essentially of, or consist of a poly(vinyl acetal) resin such as polyvinyl butyral. The poly(vinyl acetal) layer is used in connection with other coatings, bonding layers, or polymer layers described herein, and various types of multilayer intermediate layers can be manufactured. Exemplary embodiments of the multilayer intermediate layer include, but are not limited to: PVB / adhesive coating (or bonding layer) / HOE / adhesive coating (or bonding layer) / PVB, PVB / other polymer / HOE / other polymer / PVB, PVB / HOE / other polymer, PVB / HOE / PVB, and PVB / HOE / other polymer / PVB.

[0063]

[0074] Poly(vinyl acetal) resins can be produced and formed, for example, by acetalization of poly(vinyl alcohol) with one or more aldehydes in the presence of a catalyst, based on known methods such as those described in U.S. Patent Nos. 2,282,057 and 2,282,026, as well as Wade, B. 2016, Vinyl Acetal Polymers, Encyclopedia of Polymer Science and Technology. pp. 1-22 (online, copyright 2016 John Wiley & Sons, Inc.).

[0064]

[0075] Poly(vinyl acetal) resins typically have a residual hydroxyl content, ester content, and acetal content. As used herein, the residual hydroxyl content (calculated as PVOH) refers to the weight percentage of the portion having hydroxyl groups remaining on the polymer chain. For example, poly(vinyl acetal) can be produced by hydrolyzing poly(vinyl acetate) to PVOH and then reacting PVOH with an aldehyde such as butyraldehyde, propionaldehyde, preferably butyraldehyde, to produce a polymer having repeating vinyl butyral units. In the process of hydrolyzing poly(vinyl acetate), typically not all of the acetate side chain groups are converted to hydroxyl groups. For example, the reaction with butyraldehyde typically does not result in the conversion of all hydroxyl groups on PVOH to acetal groups. Thus, any finished polyvinyl butyral will typically have residual ester groups such as acetate groups (as vinyl acetate groups) and residual hydroxyl groups (as vinyl hydroxyl groups) as side chain groups on the polymer chain, as well as acetal (e.g., butyral) groups (as vinyl acetal groups). As used herein, the residual hydroxyl content is measured on a weight percentage basis in accordance with ASTM 1396.

[0065]

[0076] In various embodiments, the poly(vinyl acetal) resin includes polyvinyl butyral resin, which is also interchangeably referred to herein as "PVB". Examples of polyvinyl butyral structures are used to further illustrate how the weight percentages are based on the partial units that bind to the relevant pendant groups:

[0066]

Chemical formula

[0067]

[0077] Considering the polyvinyl butyral of the above structure, the butyral or acetal content is based on the weight percentage of unit A in the polymer, the OH content is based on the weight percentage of unit B (polyvinyl OH moiety or PVOH) in the polymer, and the acetate or ester content is based on the weight percentage of unit C in the polymer.

[0068]

[0078] The hydroxyl group content of the poly(vinyl acetal) resin is not particularly limited, but suitable amounts are at least 6, at least 8, at least 10, at least 11, at least 12, at least 13, at least 14, at least 15, at least 16, or at least 17, and in each case up to 35 weight percent of PVOH. In some embodiments, the poly(vinyl acetal) can have a residual hydroxyl content of less than 15 weight percent, or less than 14, less than 13, less than 12, less than 11, less than 10, less than 9, or less than 8 weight percent. Generally, poly(vinyl acetal) resins with lower hydroxyl weight percentages absorb more plasticizer and have the ability to absorb plasticizer more efficiently.

[0069]

[0079] The poly(vinyl acetal) resin may also contain residual ester groups, calculated as a polyvinyl ester such as acetate, of 20 wt% or less, 17 wt% or less, 15 wt% or less, 13 wt% or less, 11 wt% or less, 9 wt% or less, 7 wt% or less, 5 wt% or less, or 4 wt% or less, with the remainder being acetals such as butyraldehyde acetal, optionally also containing small amounts of other acetal groups such as, for example, 2-ethylhexanal groups (see U.S. Patent No. 5,137,954). Similar to the measurement of residual hydroxyl groups, the weight percent of residual ester groups (i.e., residual acetate content) is based on the portion of the polymer backbone that is bonded to acetate groups and contains pendant acetate groups.

[0070]

[0080] The poly(vinyl acetal) resin used in the present invention may also have an acetal content of at least 50, at least 5, at least 60, at least 65, at least 70, at least 75, at least 80, at least 85, or at least 90 wt% or more. Additionally or alternatively, the acetal content may be up to 94, up to 93, up to 92, up to 91, up to 90, up to 89, up to 88, up to 86, up to 85, up to 84, up to 83, up to 82, up to 80, up to 78, up to 77, up to 75, up to 70, or up to 65 wt%.

[0071]

[0081] The acetal groups in the poly(vinyl acetal) resin may include vinyl propynyl groups or vinyl butyral groups. In one or more embodiments, the acetal group includes a vinyl propynyl group. In some embodiments, the poly(vinyl acetal) resin may include a residue of any aldehyde, and in some embodiments, may include a residue of at least one C4-C8 aldehyde. Examples of suitable C4-C8 aldehydes can include, for example, n-butyl aldehyde, i-butyl aldehyde, 2-methyl valeraldehyde, n-hexyl aldehyde, 2-ethylhexyl aldehyde, n-octyl aldehyde, and combinations thereof. One or more poly(vinyl acetal) resins utilized in the layers and intermediate layers described herein may include at least 20, at least 30, at least 40, at least 50, at least 60, or at least 70 weight percent or more of a residue of at least one C4-C8 aldehyde, based on the total weight of the aldehyde residue of the resin. Alternatively, or additionally, the poly(vinyl acetal) resin may include 99 or less, 90 or less, 85 or less, 80 or less, 75 or less, 70 or less, or 65 weight percent or less of at least one C4-C8 aldehyde. The C4-C8 aldehyde may be selected from the group listed above, or may be selected from the group consisting of n-butyl aldehyde, i-butyl aldehyde, 2-ethylhexyl aldehyde, and combinations thereof.

[0072]

[0082] The weight average molecular weight of the poly(vinyl acetal) resin is not particularly limited. The poly(vinyl acetal) resin may have a weight average molecular weight (M w ) of at least 20,000, at least 30,000, at least 40,000, at least 50,000, at least 60,000, or at least 70,000, and is preferably up to substantially 300,000 Daltons, although in some cases higher molecular weights may be used, and there is no particular upper limit. In each case, as is known to those skilled in the art, it is measured by size exclusion chromatography using the low angle laser light scattering (SEC / LALLS) method of Cott and Ouano in tetrahydrofuran.

[0073]

[0083] A multilayer intermediate layer containing a poly(vinyl acetal) layer and one or more other polymer layers can be manufactured using any method known in the art. For example, each layer can be formed separately using techniques known in the art and then laminated together. Alternatively, a multilayer intermediate layer containing a poly(vinyl acetal) layer and one or more other polymer layers can be manufactured via coextrusion.

[0074]

[0084] In various embodiments, the HOE layer can be used with other polymer layers such as an acoustic regulation intermediate layer. Polymers exhibiting a set of desirable properties such as acoustic regulation performance often lack other desirable properties such as impact resistance or strength. Thus, to achieve a desirable combination of properties, a multilayer intermediate layer can be manufactured containing a poly(vinyl acetal) layer exhibiting desirable acoustic regulation performance and one or more other polymer layers providing impact strength and resistance. In one or more embodiments, the acoustic regulation intermediate layer can contain a poly(vinyl acetal) layer having a Tg of at least -30, at least -25, at least -20, at least -15, at least -10, at least -5, or at least 0 °C and / or less than 40, less than 30, less than 25, less than 20, less than 15, less than 10, or less than 5 °C.

[0075]

[0085] Furthermore, in various embodiments, this poly(vinyl acetal) resin or poly(vinyl acetal) layer can exhibit an improvement in acoustic regulation properties such as an improved loss tangent compared to, for example, an equivalent poly(vinyl n-butyrate) resin layer. The loss tangent is the ratio of the loss modulus (G”) in Pascals of the test object to the storage modulus (G’) in Pascals, measured by dynamic mechanical thermal analysis (DMTA). DMTA is performed using a vibration frequency of 1 Hz and a temperature sweep rate of 3 °C / min under shear mode. The peak value of the G” / G’ curve at the glass transition temperature is the loss tangent value. A higher loss tangent value can be interpreted as indicating higher damping, better sound absorption characteristics, or better acoustic regulation performance.

[0076]

[0086] Moreover, in various embodiments, the poly(vinyl acetal) resin or poly(vinyl acetal) layer may exhibit an attenuation loss coefficient, or loss coefficient, of at least 0.10, at least 0.15, at least 0.17, at least 0.20, at least 0.25, at least 0.27, at least 0.30, at least 0.33, or at least 0.35. The loss rate is measured by the mechanical impedance measurement method described in ISO standard 16940. To measure the loss coefficient, the polymer sample is laminated between two transparent glasses each having a thickness of 2.3 mm and fabricated to have a width of 25 mm and a length of 300 mm. Next, a shaker commercially available from Bruel and Kjar (Narum, Netherlands) is used to excite the laminated sample at the central point, and an impedance head is used to measure the force and vibration velocity required to excite and vibrate the bar. The obtained transfer function is recorded in a National Instrument data acquisition and analysis system, and the loss coefficient in the first vibration mode is calculated using the half-width method.

[0077]

[0087] Based on some embodiments, the poly(vinyl acetal) resin or poly(vinyl acetal) layer may exhibit desirable acoustic adjustment properties, as represented, for example, by the reduction of acoustic transmission (i.e., acoustic transmission loss) when passing through the intermediate layer. In some embodiments, the acoustic adjustment intermediate layer may exhibit an acoustic transmission loss at the coincidence frequency of at least 34, at least 34.5, at least 35, at least 35.5, at least 36, at least 36.5, or at least 37 dB, measured in accordance with ASTM E90 at 20°C. During such an acoustic transmission test, the intermediate layer is laminated between two 2.3 mm transparent glasses, and the test is performed at a reference frequency of 3,150 Hz.

[0078]

[0088] In various embodiments, in addition to the coatings or tie layers described herein, one or more of the polymers described herein can be tie layers. The tie layer can comprise, consist essentially of, or consist of a thermoplastic resin selected from the group consisting of EVA, TPU, ionomer, polyvinyl acetate, ethylene vinyl alcohol, and combinations thereof.

[0079]

[0089] The multilayer intermediate layer containing the tie layer and the HOE layer can be manufactured using any method known in the art. For example, each layer can be formed separately using techniques known in the art and then laminated together. Alternatively, the multilayer intermediate layer containing the tie layer and the HOE layer can also be manufactured based on any suitable method including, for example, extrusion coating, dip coating, solution coating, blade, paddle, air-knife, printing, powder coating, spray coating, and combinations thereof.

[0080]

[0090] An additional adhesive coating or adhesion promoter can be used in connection with the HOE layer described herein and, if desired, can strengthen the bond between the HOE layer and various other layers in the multilayer intermediate layer. In such embodiments, the adhesive coating can be at least partially interposed and / or positioned between the intermediate layer and the HOE layer. In an embodiment, the adhesion promoter can be a silane adhesion promoter. Method for manufacturing the intermediate layer

[0091] Based on various embodiments of the present invention, the intermediate layer can be made by any suitable process known to those skilled in the art of manufacturing the intermediate layer, without being limited to its manufacturing method. For example, it is contemplated that the bonding layer, polymer layer or intermediate layer can be formed by extrusion or coextrusion. In the extrusion process, one or more of the thermoplastic resins, plasticizers, and optionally one or more additives already described can be premixed and fed into an extrusion apparatus. The extrusion apparatus is configured to impart a specific shape to the thermoplastic composition to create an extruded sheet. The extruded sheet at elevated temperature can then be cooled to form a polymer sheet. Once the sheet is cooled and fixed, it may be cut and rolled for subsequent storage, transportation, and / or use as an intermediate layer.

[0081]

[0092] Coextrusion is a process in which multiple layers of polymer materials are extruded simultaneously. Generally, this type of extrusion utilizes two or more extruders to melt and deliver various thermoplastic melts of different viscosities or other properties with a stable volumetric throughput through a coextrusion die to achieve the desired final form. The thickness of the multiple polymer layers exiting the extrusion die in the coextrusion process can generally be controlled by adjusting the relative speed of the melts passing through the extrusion die and by the size of the individual extruders handling each of the melted thermoplastic resin materials.

[0082]

[0093] The extrusion process can occur at temperatures known to those skilled in the art depending on the materials and applications. The bonding layer, polymer layer and intermediate layer described herein can be manufactured based on any suitable method. The resulting resin composition can be formed into a sheet or layer based on any suitable method including, but not limited to, solution casting, compression molding, injection molding, melt extrusion, melt blowing, and combinations thereof. If the layer or intermediate layer is a multilayer intermediate layer comprising two or more layers or sheets, such multilayer intermediate layers can also be manufactured based on any suitable method including, for example, coextrusion, blown film, melt blowing, dip coating, solution coating, blade, paddle, air-knife, printing, powder coating, spray coating, and combinations thereof.

[0083]

[0094] Alternatively, each bonding layer and / or polymer layer of the intermediate layer can be formed or extruded separately onto a sheet, and the sheets can be stacked to form a laminate structure in a desired order and then compressed under heat and pressure to form a multilayer intermediate layer. In various embodiments of the present invention, the bonding layer, polymer layer or intermediate layer can be formed by extrusion or coextrusion. In the extrusion process, one or more thermoplastic polymers, plasticizers, and optionally at least one additive can be premixed and fed into an extrusion apparatus, and the layer or intermediate layer can be melted and extruded from a die, thereby providing an extruded sheet. Alternatively, one or more layers can be purchased or manufactured separately using processes known in the art.

[0084]

[0095] Other additives may be incorporated into any one of the above layers used to form the laminate or intermediate layer to improve the performance of the final product and impart certain additional properties to the intermediate layer. Such additives include, among other additives known to those skilled in the art, adhesion modifiers, antiblocking agents, dyes, pigments, stabilizers (e.g., ultraviolet stabilizers), antioxidants, flame retardants, IR absorbers or blockers (e.g., indium tin oxide, antimony tin oxide, lanthanum hexaboride (LaB6) and tungsten sesquioxide), processing aids, flow improvers, lubricants, impact resistance modifiers, nucleating agents, heat stabilizers, UV absorbers, dispersants, surfactants, chelating agents, coupling agents, adhesives, primers, reinforcing additives, and fillers but are not limited thereto.

[0085]

[0096] Additives in the form of liquids, powders, or pellets are often used and can be mixed with the thermoplastic resin or plasticizer either before arriving at the extruder apparatus or in combination with the thermoplastic resin within the extruder apparatus. These additives are incorporated into the composition and further into the resulting intermediate layer, improving the specific properties and performance of the intermediate layer in the multilayer glass panel product. Laminate including HOE layer

[0097] The bonding layers and intermediate layers described heretofore can have improved properties and are useful with certain films such as HOE films. A bonding layer including at least one LRIC can be combined with an HOE film through a process known in the art such as encapsulation. In embodiments, the HOE film can have a bonding layer (and optional intermediate layer) including at least one LRIC on one side (such as the HOE side of the HOE film) or on both sides. In other embodiments, the HOE film can have a bonding layer including at least one LRIC on the HOE side of the HOE film and another bonding layer on the substrate side of the HOE film.

[0086]

[0098] Other combinations of layers are possible and may be used, such as additional intermediate layers, multilayer intermediate layers, and / or intermediate layers having the functional properties described heretofore. Properties and end uses

[0099] The formed structure can be used in many applications such as laminates or panels including one or more rigid substrates. Panels made of the HOE films, bonding layers and intermediate layers described herein, such as glass panels including an intermediate layer laminated between two glass substrates, can have good optical transparency. The transparency of the bonding layer and the intermediate layer laminated between the glass substrates can be determined by measuring the haze value, which is the quantification of the amount of light not transmitted through a sheet glass panel containing a multilayer intermediate layer. The percent haze can be measured according to the following technique. An instrument for measuring the amount of haze, a haze meter, Model D25, is available from Hunter Associates (Reston, Va.) and can be used with a light source C at two observation angles in accordance with ASTM D1003-61 (reapproved in 1977) - Procedure A. In various embodiments such as front glass, the intermediate layer described herein can exhibit a haze of less than 10, less than 9, less than 8, less than 7, less than 6, less than 5, less than 4, less than 3, less than 2, less than 1.5, less than 1, less than 0.75, or less than 0.5 percent when measured in accordance with ASTM D1003-61. In other embodiments, the optical properties may not be as important, or a lower transparency may be desired, in which case a higher haze level may be desirable or acceptable.

[0087]

[0100] Another parameter used to determine optical performance is transparency, or percent visual transmittance (%T vis) and is measured using a spectrophotometer such as a HunterLab UltraScan XE, in accordance with ASTM D1003, Procedure B, using a light source C at an observation angle of 2°. The values provided herein were obtained by analyzing a polymer sample laminated between two sheets of clear glass (commercially available from Pittsburgh Glass Works, Pittsburgh, PA), each having a thickness of 2.3 mm. In some embodiments where high haze transmittance is desired, the resin compositions, layers, and intermediate layers of the present invention can have a percent haze transmittance of at least 50, at least 70, at least 80, at least 81, at least 82, at least 83, at least 84, at least 85, at least 85.5, at least 86, at least 86.5, at least 87, at least 87.5, at least 88, or at least 90 percent or more. For applications where a lower haze transmittance is desired, the percent haze transmittance can be less than 50 percent.

[0088]

[0101] The yellowness index ("YI") is another criterion for optical quality. The yellow chromaticity index is measured from the spectrophotometric light transmittance in the visible spectrum using a HunterLab UltraScan XE, in accordance with ASTM method E313 (formerly D-1925) (light source C, 2° observation angle), by laminating (and autoclaving) a 30 gauge (30 mil or 0.76 mm) sheet sample between two 2.3 mm clear glass sheets. In various embodiments, the intermediate layer can exhibit a yellowness index of less than 20, less than 18, less than 16, less than 14, less than 12, less than 10, less than 8, less than 6, less than 5, less than 4, less than 3, less than 2, 1.5, less than 1.0, less than 0.75, less than 0.5, less than 0.4, or less than 0.3, in accordance with ASTM E313.

[0089]

[0102] Based on embodiments of the present invention, the HOE film, bonding layer, and optional intermediate layer The structure containing can be used in a multilayer panel or laminate including at least one substrate such as a rigid substrate. As used herein, "rigid" is generally relative to other layers. Any suitable rigid substrate may be used, and in some embodiments, it may be selected from the group consisting of glass, polycarbonate, biaxially oriented PET, copolyester, acrylic, polyamide, cellulose triacetate, and combinations thereof. When the rigid substrate contains a polymeric material, the polymeric material may or may not include a hard coating surface layer. In some embodiments, the multilayer panel or laminate includes a pair of rigid substrates with a resin intermediate layer disposed therebetween. In other embodiments, the multilayer panel includes a rigid substrate and an intermediate layer including an HOE layer therebetween, and optionally including a bonding layer, an adhesive coating, and / or an adhesion promoter if necessary.

[0090]

[0103] In various embodiments, the structure containing the bonding layer and intermediate layer of the present invention is typically most commonly used in a multilayer panel including two substrates, such as a pair of glass substrates with an HOE film, a bonding layer, and an intermediate layer disposed between the two substrates. These examples of multilayer panels are not intended to be limiting in any way, as those skilled in the art will readily recognize that numerous configurations other than those described above can be made using the intermediate layer of the present invention.

[0091]

[0104] The bonding layer or coating and optional polymeric intermediate layer described herein The construct containing can be laminated between glasses using techniques known in the art. A typical glass lamination process includes the following: (1) steps of assembling one or two substrates (e.g., glass), an intermediate layer, a bonding layer, and an HOE film; (2) steps of heating the assembly for a short time via IR radiation or convective means; (3) steps of passing the assembly through a pressure nip roll for the first degassing; (4) steps of heating the assembly a second time at an appropriate temperature, such as about 50 °C to about 120 °C, to perform sufficient temporary bonding to seal the ends of the intermediate layer in the assembly; (5) steps of passing the assembly through a second pressure nip roll to further seal the ends of the intermediate layer to enable further operations; (6) steps of autoclaving the assembly for about 30 to 90 minutes at appropriate temperatures and pressures, such as temperatures between 80 and 150 °C and pressures between 15 psig and 200 psig. Other commercially implemented means known in the art for use in the degassing (steps 2 to 5) of the intermediate layer - glass interface include the processes of vacuum bags and vacuum rings where vacuum is utilized to remove air. Alternative lamination processes include the use of a vacuum laminator that first degasses the assembly and then completes the lamination at a sufficiently high temperature and reduced pressure.

[0092]

[0105] The preferred forms of the present invention described above should be used only by way of illustration and should not be used in a limiting sense for interpreting the scope of the present invention. Modifications to the exemplary embodiments explicitly described above can be readily made by those skilled in the art without departing from the spirit of the present invention. The present invention can be further illustrated by the following examples of those embodiments, but it is understood that these examples are included for illustrative purposes only and are not intended to limit the scope of the present invention, particularly unless otherwise stated.

Examples

[0093]

[0106] Various laminates having the configurations described below (having various thicknesses and different Separate films and bonding layers of different materials such as PVB, TPU, EVA, ionomers, and others, with the type and amount of plasticizer involved, can be produced by making them into layers via a manual lamination method together with the HOE film or layer. The coating or bonding layer can be applied using any known industrial process such as dissolving an adhesive material (e.g., PVB resin) in a solution containing an organic solvent or forming an aqueous solution of the adhesive material, subjecting the solution to a roll-to-roll slot die process, and subsequently evaporating the organic solvent or water in a furnace. Alternatively, the material may be applied either alone, as a suspension, or dissolved in another material known to those skilled in the art by other coating or welding techniques. The HOE film uses holographic technology to change the way light travels through the medium and is composed of a series of connected continuous optical elements that create a mirror-like surface by reflecting light at a specific set of angles (while not reflecting light at other angles), and is a single-element polymer film. The structure formed by the coating or bonding layer, the protective substrate, the HOE film, and the optional polymer layer is then laminated between two annealed glass sheets such as glass sheets each having a thickness of 2.3 mm. The lamination process utilizes a vacuum laminator to laminate all samples, which includes: (1) the step of assembling the substrate, the intermediate layer, and the HOE film in a predetermined order and placing them in a vacuum bag; (2) the step of reducing the pressure at room temperature for 20 minutes and then at 105°C for an additional 60 minutes; and (3) the step of removing the sample from the vacuum bag and autoclaving it under fixed conditions of 125°C and 13 bar for 40 minutes. As further described below, multiple samples can be produced using this lamination technique.

[0094]

[0107] The control laminate having a glass / PVB / HOE / PVB / glass configuration has been conventional It can be manufactured using a two-layer polymer intermediate layer such as PVB compounded with a plasticizer (such as 3GEH plasticizer), and a HOE film encapsulated between two PVB layers. Next, the laminate stack is laminated in a vacuum bag degassing process, followed by a standard autoclave lamination process known in the art. The completed configuration includes an operative volume hologram having a peak reflection close to the initially programmed wavelength. The signal intensity of the hologram is reduced due to a decrease in the concentration of the LRIC plasticizer in the HOE layer after redistribution over the total thickness of the volume hologram layer and the PVB layer encapsulating the holographic element or volume hologram.

[0095]

[0108] A laminate example having the configuration described below may also have a coating or bonding layer, using a HOE film and an optional polymer layer, and can be manufactured in the same manner by laminating this structure between one or two rigid substrates shown below.

[0096] Comparative example

[0109] Figure 3 shows a holographic element and a holographic element substrate encapsulated between two intermediate layers without a bonding layer or coating and a protective substrate, representing a control embodiment of a glass laminate containing a HOE film. As shown in Figure 3, the intermediate layers 2 and 8 encapsulate a HOE film (consisting of a holographic element 6 and a holographic element substrate 7) to form a multilayer structure, and the entire multilayer structure is interposed between two rigid substrates 1 and 9 such as glass.

[0097] Example 1

[0110] Figure 4 shows a holographic element and a holographic element substrate encapsulated between two intermediate layers, representing a cross-sectional view of an embodiment of a glass laminate containing a HOE film, where a protective element substrate and a protective element bonding layer are adjacent to the HOE film. In Figure 4 ​​As shown, the protective bonding layer 5 is located adjacent to the holographic element 6, and the protective substrate 4 is adjacent to the bonding layer 5 and the intermediate layer 2. The intermediate layers 2 and 8 encapsulate the HOE film (consisting of the holographic element 6 and the holographic element substrate 7), the bonding layer 5, and the protective substrate 4 to form a multilayer structure, and the entire multilayer structure is interposed between two rigid substrates 1 and 9 such as glass.

[0098]

[0111] In the embodiment shown in FIG. 4, the intermediate layer can be any polymer film such as PVB, TPU, EVA, ionomer - or any of the above-mentioned polymers. The protective bonding layer 5 is adjacent to and in direct contact with the holographic element 6 on one side and the protective substrate 4 on the other side. The bonding layer can be any material that provides the necessary adhesiveness between the HOE film (or the holographic element 6) and the protective substrate 4 such as PVB, TPU, EVA, ionomer or other polymers known in the art. The bonding layer 5 contains LRIC such as (bis(2,2,3,3,4,4,5,5,6,6,7,7-dodecafluoroheptyl)(2,2,4-trimethylhexane-1,6-diyl)biscarbamate (fluorinated LRIC plasticizer) plasticizer. An adhesion promoter may also be used to improve the interlayer adhesiveness if desired. The protective substrate 4 provides a barrier or protective layer that prevents the plasticizer (or other materials) from moving from the intermediate layer to the holographic element and prevents the LRIC and other materials in the holographic element 6 from moving out of the holographic element and thus reducing the effectiveness of the HOE film. The protective substrate 4 can be any of the materials described above such as PET, PEN, polycarbonate, polyamide, polyimide, cellulose ester, polyester. The protective substrate may be the same material as the holographic element substrate 7 or different.

[0099] Example 2

[0112] FIG. 5 shows a holographic element encapsulated between two intermediate layers and a ho Shows a holographic element substrate and represents a cross-sectional view of another embodiment of a glass laminate containing a HOE film, where the protective element substrate is encapsulated by two protective element bonding layers adjacent to the HOE film. As shown in FIG. 5, the protective bonding layer 5 is located adjacent to the holographic element 6, and the protective substrate 4 is adjacent to the bonding layer 5. The second bonding layer 3 is adjacent between the protective substrate 4 and the intermediate layer 2. The intermediate layers 2 and 8 encapsulate the HOE film (consisting of the holographic element 6 and the holographic element substrate 7), the bonding layers 3 and 5, and the protective substrate 4 to form a multilayer structure, and the entire multilayer structure is interposed between two rigid substrates 1 and 9 such as glass.

[0100]

[0113] In the embodiment shown in FIG. 5, the polymer intermediate layers 2 and 8 can be any polymer film such as PVB, TPU , EVA, ionomer, or any of the polymers described above. The protective bonding layer 5 is adjacent to and in direct contact with the holographic element 6 on one side and the protective substrate 4 on the other side. The bonding layer 5 can be any material that provides the necessary adhesiveness between the HOE film (or holographic element 6) and the protective substrate 4 such as PVB, TPU, EVA, ionomer, or other polymers known in the art. The bonding layer contains LRIC such as a fluorinated LRIC plasticizer. An adhesion promoter may also be used to improve the interlayer adhesiveness if desired. The protective substrate 4 provides a barrier or protective layer that prevents the plasticizer (or other material) from moving from the intermediate layer to the holographic element and prevents the LRIC and other materials in the holographic element 6 from moving out of the holographic element and thus reducing the effectiveness of the HOE film. The protective bonding layer 3 may be the same as or different from the protective bonding layer 5. In addition, the protective bonding layer 3 may be adjacent to the protective substrate 4 and may contain a different or additional plasticizer to prevent unwanted plasticizer movement to the holographic element 6. The protective substrate 4 can be any of the materials described above such as PET, PEN, polycarbonate, polyamide, polyimide, cellulose ester, polyester. The protective substrate is of the same material as the holographic element substrate 7 It may be present or may be different.

[0101] Example 3

[0114] FIG. 6 shows a holographic element and a holographic element substrate encapsulated between one intermediate layer and a protective element substrate encapsulated by two protective element bonding layers adjacent to the HOE film. FIG. 6 represents a cross-sectional view of another embodiment of a glass laminate containing an HOE film. As shown in FIG. 6, the protective bonding layer 5 is located adjacent to the holographic element 6, and the protective substrate 4 is adjacent to the bonding layer 5. The second bonding layer 3 is adjacent to the protective substrate 4. The intermediate layer 8 is adjacent to the holographic element substrate 7. The bonding layer 3 and the intermediate layer 8 encapsulate the HOE film (consisting of the holographic element 6 and the holographic element substrate 7), the bonding layer 5 and the protective substrate 4 to form a multilayer structure, and the entire multilayer structure is interposed between two rigid substrates 1 and 9 such as glass.

[0102]

[0115] In the embodiment shown in FIG. 6, the intermediate layer 8 is made of PVB, TPU, EVA, iono It can be any polymer film such as a MAR or any of the aforementioned polymers. The protective bonding layer 5 is adjacent to and in direct contact with the holographic element 6 on one side and the protective substrate 4 on the other side. The bonding layer 5 can be any material that provides the necessary adhesiveness between the HOE film (or holographic element 6) and the protective substrate 4 such as PVB, TPU, EVA, ionomer or other polymers known in the art. The bonding layer contains LRIC such as a fluorinated LRIC plasticizer. An adhesion promoter may also be used to improve the interlayer adhesiveness if desired. The protective substrate 4 provides a barrier or protective layer that prevents the plasticizer (or other materials) from moving from the intermediate layer to the holographic element and prevents the LRIC and other materials in the holographic element 6 from migrating out of the holographic element, thus preventing reduction of the effectiveness of the HOE film. The protective bonding layer 3 may be the same as or different from the protective bonding layer 5. Additionally, the protective bonding layer 3 may contain different or additional plasticizers to prevent unwanted plasticizer migration to the holographic element 6 adjacent to the protective substrate 4. The protective substrate 4 can be any of the materials described above such as PET, PEN, polycarbonate, polyamide, polyimide, cellulose ester, polyester. The protective substrate may be the same as or different from the holographic element substrate 7.

[0103] Example 4

[0116] Figure 7 shows a cross-sectional view of another embodiment of a glass laminate having only one glass or rigid layer and containing an HOE film, showing a holographic element and a holographic element substrate protected by a coating or bonding layer. As shown in Figure 7, the protective bonding layer 5 is positioned adjacent to the HOE film (including the holographic element 6 and the holographic element substrate 7). The bonding layer 5 and the HOE film form a multilayer structure that bonds to a rigid substrate 1 such as glass. The multilayer structure of Figure 7 can then be bonded to a second rigid substrate or, if desired, to another device for use in another application.

[0104]

[0117] In the embodiment shown in FIG. 7, one side of the protective bonding layer 5 is adjacent to and in direct contact with the holographic element 6, and the other side is adjacent to and in direct contact with the rigid substrate 1. The bonding layer 5 can be any material that provides the necessary adhesiveness between the HOE film (or holographic element 6) and the rigid substrate 1 such as PVB, TPU, EVA, ionomer, or other polymers known in the art. The bonding layer 5 contains LRIC such as a fluorinated LRIC plasticizer. An adhesion promoter may also be used to improve the adhesion between layers if desired.

[0105] Example 5

[0118] FIG. 8 shows a cross-sectional view of another embodiment of a glass laminate having only one glass or rigid layer and containing an HOE film, the holographic element and the holographic element substrate protected by a protected element substrate encapsulated by two protective element bonding layers adjacent to the HOE film. As shown in FIG. 8, the protective bonding layer 5 is positioned adjacent to the holographic element 6, and the protective substrate 4 is adjacent to the bonding layer 5. The second bonding layer 3 is adjacent to the protective substrate 4. The bonding layers 3 and 5, the protective substrate 4, and the HOE film form a multilayer structure that is bonded to a rigid substrate such as glass. The multilayer structure of FIG. 8 can then be bonded to a second rigid substrate or, if desired, to another device and used for another application.

[0106]

[0119] In the embodiment shown in FIG. 8, one side of the protective bonding layer 5 is adjacent to the holographic element ​Adjacent to and in direct contact with 6, the protective substrate 4 is adjacent to the bonding layer 5. The second bonding layer 3 is adjacent to the protective substrate 4. The bonding layer 5 can be any material that provides the necessary adhesiveness between the HOE film (or holographic element 6) and the rigid substrate 1 such as PVB, TPU, EVA, ionomer or other polymers known in the art. The bonding layer 5 contains LRIC such as a fluorinated LRIC plasticizer. The protective bonding layer 3 may be the same as or different from the protective bonding layer 5. Additionally, the protective bonding layer 3 may be adjacent to the protective substrate 4 and may contain different or additional plasticizers to prevent unwanted plasticizer migration to the holographic element 6. The protective substrate 4 can be any of the materials described above such as PET, PEN, polycarbonate, polyamide, polyimide, cellulose ester, polyester. The protective substrate may be the same as or different from the holographic element substrate 7. An adhesion promoter may also be used to improve the adhesion between layers if desired.

[0107]

[0120] Incorporating the LRIC plasticizer into the bonding layer described above provides a laminate having a HOE film in which the signal strength can be maintained. When using a blend of LRIC and a conventional plasticizer, the signal strength is slightly reduced but is better than a laminate in which only a conventional plasticizer such as 3GEH is used in the bonding layer.

[0108]

[0121] A structure manufactured with a bonding layer that does not contain fluorinated LRIC effectively has a reflection signal It exhibits a significantly low holographic efficiency, observed through a significant reduction in signal strength. Incorporation of LRIC, such as fluorinated LRIC, into the coating or bonding layer (and optionally into the polymer layer) generally makes it possible to maintain the signal strength. This effect is achieved by incorporating sufficient fluorinated LRIC into the bonding layer to prevent a concentration gradient, which, if not incorporated, results in the migration of fluorinated LRIC out of the original HOE film and into the bonding layer or coating. This effect also occurs with LRICs of different chemical compositions; as long as the concentration level in the bonding layer is designed in such a way as to prevent the diffusion of LRIC from the HOE film into the bonding layer, it can be an LRIC with a refractive index gradient maintained in the HOE.

[0109]

[0122] Changing the formulation can also lead to an improvement in the results after HOE lamination. Low Manufacturing a construct with a low level of 3GEH plasticizer can result in a reduction in HOE strength loss compared to a construct having a bonding layer or coating containing only a conventional plasticizer such as 3GEH. Changes to the chemical properties of PVB can also result in a similar improvement. However, in many polymer layers, while formulation changes can assist in improving distribution, it is doubtful that they can completely prevent LRIC loss from the HOE to a bonding layer that does not contain LRIC. However, it has been found that improvements to the chemical intermediate layer formulation are particularly effective when combined with the addition of LRIC.

[0110]

[0123] As long as the LRICs present in the bonding layer and the HOE film are chemically similar and reasonably compatible in refractive index, it is also expected that a similar improvement can be achieved by formulating the bonding layer with an LRIC different from the LRIC present in the HOE. Different LRICs with different chemical structures can be used to achieve the same effect, but careful selection is required to achieve the distribution ratio that maintains the desired lattice spacing and refractive index within the HOE film.

[0111]

[0124] Some HOE films are produced without the use of LRIC and instead use polymer Depending on the refractive index of the grating, the holographic effect is reached. In such cases, it is possible to provide such HOE films with a refractive index modifier using a bonding layer with LRIC to increase the refractive index difference between the grating phases. Such an approach increases the effectiveness of the hologram in general.

[0112]

[0125] These LRICs are incorporated into the tie layer during lamination (i.e., the LRICs are It is also possible to simplify the HOE film fabrication process by designing a holographic photopolymer film without an LRIC, with the understanding that the LRIC transfers from the tie layer to the HOE film. In this way, the tie layer effectively becomes the LRIC delivery system. In such a case, it is expected that the HOE patterning system would have to be modified to produce stripes with initial dimensions that are designed to change to the desired levels following post-lamination LRIC equilibration. definition

[0126] It is understood that the following is not intended to be an exclusive list of defined terms. Other definitions may be given in the above description, for example, with use of the defined terms in context.

[0113]

[0127] As used herein, the terms "a," "an," and "the" refer to one means one or more.

[0128] As used herein, the term "and / or" refers to a sequence of two or more items. When used in a list, it means that any one of the listed items may be utilized alone, or any combination of two or more of the listed items may be utilized. For example, if a composition is described as containing components A, B, and / or C, the composition may contain A only; B only; C only; a combination of A and B; a combination of A and C, a combination of B and C; or a combination of A, B, and C.

[0114]

[0129] As used herein, the terms "comprising," "comprises," and "comprise" are non-limiting transitional terms used to shift from the subject recited before the term to one or more elements recited after the term, and the elements or plurality of elements recited after the transitional term are not necessarily limited to a single element that constitutes the subject. As used herein, the terms "having," "has," and "have" have the same non-limiting meaning as "comprising," "comprises," and "comprise" recited above. As used herein, the terms "including," "include," and "included" have the same non-limiting meaning as "comprising," "comprises," and "comprise" recited above.

[0115]

[0130] As used herein, the term "about" refers to a value within 10 percent of the recited value. This description uses numerical ranges to quantify specific parameters related to the present invention. It should be understood that when a numerical range is provided, such a range should be interpreted as providing literal support for a claim limitation that recites only the lower limit value of the range as well as for a claim limitation that recites only the upper limit value of the range, similar to claim limitations that recite only the lower limit value of the range. For example, the disclosed numerical range of 10 to 100 provides literal support for claims that recite "greater than 10" (without an upper limit) and for claims that recite "less than 100" (without a lower limit).

[0116]

[0131] In certain embodiments, the multiple polymer layers or substrate layers produce a laminate structure. It can be used in a manufacturing method. In such a case, the polymer or substrate layer may be described as the first or second polymer or substrate layer. As used herein, the terms "first", "second", etc. are used to describe various elements, but such elements should not necessarily be limited by these terms. These terms are only used to distinguish one element from another and do not necessarily imply a specific order or even a specific element. For example, an element may be considered the "first" element in this description and may be considered the "second" element without contradiction in the claims. Consistency is maintained within the description and for each independent claim, but such a terminology system is not necessarily intended to be consistent between them.

[0117]

[0132] Examples of various bonding layers and and optional polymer intermediate layers and laminates containing these bonding layers include, but are not limited to, the following. Those skilled in the art will understand that various combinations and properties can be changed as desired.

[0118]

[0133] The bonding layer can be used to encapsulate the polymer volume hologram, and the bonding layer contains a total amount of plasticizer within the range of -25 to 25 weight percent of the concentration of plasticizer in the original polymer volume hologram. In embodiments, the bonding layer contains a total amount of plasticizer within the range of -15 to 15 weight percent, or -10 to 10 weight percent, -5 to 5 weight percent of the concentration of plasticizer in the original polymer volume hologram.

[0119]

[0134] In embodiments, the bonding layer includes a polymer or elastomer or blend of polymers or elastomers selected from polyurethane, poly(vinyl butyral), etc. poly(vinyl acetal), ethylene vinyl acetate copolymer, polyvinyl alcohol, and ionomer.

[0120]

[0135] In an embodiment, the bonding layer contains a plasticizer or a plasticizer blend that is the same as the plasticizer or plasticizer blend in the polymer volume hologram. In other embodiments, the bonding layer contains at least one plasticizer or plasticizer blend that is different from the plasticizer or plasticizer blend in the polymer volume hologram.

[0121]

[0136] In an embodiment, the bonding layer is such that the plasticizer or plasticizer blend has a refractive index within the range of -0.1 to +0.1 of the refractive index of the plasticizer or plasticizer blend in the original polymer volume hologram. In an embodiment, the plasticizer or plasticizer blend is selected to have a refractive index within the range of -0.05 to +0.05, or -0.02 to +0.02 of the refractive index of the plasticizer or plasticizer blend in the original polymer volume hologram.

[0122]

[0137] In an embodiment, the multilayer structure includes a bonding layer, an optional polymer intermediate layer, and a polymer volume hologram, and the bonding layer is in direct contact with the polymer volume hologram. In other embodiments, the multilayer structure includes a second bonding layer. The bonding layer may contain any of the above-described polymers. In other embodiments, a polymer intermediate layer is also included, and the polymer intermediate layer is adjacent to a protective substrate that is between the polymer intermediate layer and the bonding layer.

[0123]

[0138] In an embodiment, the polymer intermediate layer is selected to minimize the uptake of plasticizer such that the plasticizer level in the fully encapsulated polymer volume hologram is at least 50%, at least 60%, at least 70%, at least 80%, or at least 90% of the starting level of plasticizer.

[0124]

[0139] In an embodiment, the polymer film has a thickness in the range of 0.05 mm to 1.5 mm, 0.1 mm to 0.8 mm, or 0.2 mm to 0.4 mm.

[0140] In an embodiment, the coating or bonding layer is at least about 5 micrometers (microns), at least 10, at least 15, at least 20, at least 25, at least 30, at least 35, at least 40, at least 45, or at least 50 micrometers (microns) or more in thickness. Other thicknesses may be used depending on the desired properties and the materials used.

[0125]

[0141] In an embodiment, the bonding layer further includes an adhesion promoter. In an embodiment, the adhesion promoter includes a silane adhesion promoter. In an embodiment, the adhesion promoter is incorporated into the bonding layer.

[0142] In an embodiment, a polymer intermediate layer is also included, and the polymer intermediate layer has additional functionality such as acoustic regulation shielding acoustic characteristics, a wedge shape at a fixed or variable angle, a dye, particles, an infrared or sunlight absorber, or a layer that selectively blocks a portion of the electromagnetic spectrum.

[0126]

[0143] In an embodiment, a first and a second polymer intermediate layer are included, and in some embodiments the polymer intermediate layers are the same. In other embodiments, the first and second polymer intermediate layers are different. In an embodiment, at least one of the first and second polymer intermediate layers is a multilayer intermediate layer.

[0127]

[0144] In an embodiment, two or more bonding layers are used. The bonding layers may be the same or different from each other.

[0145] In an embodiment, the laminate further includes a bonding layer disposed between the first polymer layer and the polymer volume hologram. In an embodiment, the laminate further includes a bonding layer disposed between the second polymer layer and the polymer volume hologram. In an embodiment, the laminate further includes a bonding layer disposed between both the first polymer layer and the polymer volume hologram and the second polymer layer and the polymer volume hologram.

[0128]

[0146] In an embodiment, the bonding layer is used to encapsulate the polymer volume hologram, and the optical modulation characteristics of the polymer volume hologram are such that after lamination and low refractive index compound equilibration with the polymer intermediate layer, they are greater than 70%, preferably greater than 80%, most preferably greater than 90% of the magnitude of the original optical modulation characteristics in at least one wavelength range. The bonding layer contains a certain concentration of a low refractive index compound for use in lamination with the polymer volume hologram film.

[0129]

[0147] In an embodiment, the structure includes a polymer volume hologram and a bonding layer used to encapsulate the polymer volume hologram. The bonding layer contains a certain concentration of a low refractive index compound, and the optical modulation characteristics of the polymer volume hologram are greater than 70% of the magnitude of the original optical modulation characteristics in at least one wavelength range after lamination and low refractive index compound equilibration with the bonding layer.

[0130]

[0148] In an embodiment, the structure includes a polymer volume hologram without a low refractive index compound and a bonding layer used to encapsulate the polymer volume hologram. The bonding layer contains a certain concentration of a low refractive index plasticizer, and the optical modulation characteristics of the polymer volume hologram are greater than 70% of the magnitude of the original optical modulation characteristics in at least one wavelength range after lamination and low refractive index compound equilibration with the bonding layer. In an embodiment, the optical modulation characteristics of the polymer volume hologram are greater than 80%, 90%, 100%, 200%, 300%, 400%, 500%, 600%, 700%, 800%, 900%, or 1000% of the magnitude of the original optical modulation characteristics in at least one wavelength range after lamination and low refractive index compound equilibration with the bonding layer.

[0131]

[0149] In an embodiment, the structure includes a polymer volume hologram and a bonding layer adjacent to the polymer volume hologram. The bonding layer contains a low refractive index compound at a concentration within the range of -25 to +25 weight percent of the concentration of the low refractive index compound in the polymer volume hologram. ​

[0132]

[0150] In an embodiment, the bonding layer contains a total amount of plasticizer within the range of 0 to 50 weight percent of the structure. In an embodiment, the bonding layer contains a polymer or elastomer selected from polyurethane, poly(vinyl acetal) such as poly(vinyl butyral), ethylene vinyl acetate copolymer, polyvinyl alcohol, cellulose ester, polyolefin elastomer, acrylic resin, polysiloxane, and ionomer, or a blend of polymers or elastomers.

[0133]

[0133]

[0151] In an embodiment, the bonding layer contains at least one low refractive index compound selected to have a refractive index within the range of -0.1 to +0.1 of the refractive index of the low refractive index compound in the polymer volume hologram.

[0134]

[0134]

[0152] In an embodiment, the bonding layer is in direct contact with the polymer volume hologram. In an embodiment, the multilayer intermediate layer further includes a polymer intermediate layer, and the polymer intermediate layer is adjacent to a protective substrate between the polymer intermediate layer and the bonding layer. In an embodiment, the polymer intermediate layer contains a low refractive index compound, and the low refractive index compound in the polymer intermediate layer allows movement from the polymer intermediate layer to the polymer volume hologram, from the polymer volume hologram to the polymer intermediate layer, or both from the polymer intermediate layer to the polymer volume hologram and from the polymer volume hologram to the polymer intermediate layer. In an embodiment, the polymer intermediate layer is selected such that the low refractive index compound level in the polymer volume hologram is at least 50% of the starting level of the low refractive index compound originally contained within the polymer volume hologram film.

[0135]

[0135]

[0153] In an embodiment, the multilayer intermediate layer includes a second bonding layer. In an embodiment, the multilayer intermediate layer includes a second polymer intermediate layer, and at least one of the first and second polymer intermediate layers is a multilayer polymer intermediate layer.

[0136]

[0136]

[0154] In an embodiment, the bonding layer incorporates a low refractive index compound in excess of 50% for proper functionalization of a complete laminate structure containing the bonding layer and the polymer volume hologram.

[0155] In an embodiment, there is a non-patterned photosensitive polymer film designed for fabrication of a polymer volume hologram film for use in lamination with an intermediate layer containing a refractive index modifying plasticizer at a level in excess of 50%, preferably in excess of 75%, preferably in excess of 90% to achieve proper functionalization of a complete laminate structure containing the polymer intermediate layer and the polymer volume hologram, and fabricated without using a refractive index modifying plasticizer or a plasticizer blend.

[0137]

[0156] In an embodiment, there is a patterned polymer volume hologram film that does not use a refractive index modifying plasticizer or a plasticizer blend for use in lamination with an intermediate layer containing a refractive index modifying plasticizer at a level in excess of 50%, preferably in excess of 75%, preferably in excess of 90% to achieve proper functionalization of a complete laminate structure containing the polymer intermediate layer and the polymer volume hologram.

[0138]

[0157] In an embodiment, the polymer volume hologram includes a patterned or non-patterned photosensitive polymer film, and the polymer volume hologram does not contain a plasticizer during manufacture.

[0158] In an embodiment, the grating is patterned to achieve a desired optical response following re-equilibration of the plasticizer after lamination. In an embodiment, the light modulation efficiency of the grating increases by at least 25%, at least 50%, at least 75%, at least 100%, at least 500%, or at least 1000% following re-equilibration of the plasticizer after lamination.

[0139]

[0159] In an embodiment, the manufacturing method involves a set of refractive It includes the production of a rate grid, and the pattern of the grid is designed to achieve the desired pattern only after lamination and equilibration of the low refractive index compound.

[0140]

[0160] In an embodiment, the substrate includes glass, polycarbonate, polyethylene terephthalate, acrylic, polyester, polyamide, or cellulose triacetate.

[0161] In an embodiment, the laminate includes at least one substrate and any of the multilayer intermediate layers described herein. ​

Claims

**Claim 1** Providing a first polymer layer, a bonding layer containing a low refractive index compound, and a polymer volume hologram; assembling the first polymer layer, the bonding layer, and the polymer volume hologram to form an assembly; providing at least a first substrate, wherein the first substrate is adjacent to the first polymer layer; and laminating the assembly and at least the first substrate to form a laminated structure, wherein the optical modulation characteristics of the polymer volume hologram are more than 70% of the magnitude of the original optical modulation characteristics of the polymer hologram before assembly in at least one wavelength range after equilibration of the low refractive index compound with the lamination and the bonding layer, and the laminated structure has a low refractive index compound level distributed within the polymer volume hologram. A manufacturing method. **Claim 2** The manufacturing method according to claim 1, wherein the initial polymer volume hologram does not contain a low refractive index compound. **Claim 3** The manufacturing method according to claim 1, wherein the initial polymer volume hologram contains at least one low refractive index compound. **Claim 4** The manufacturing method according to any one of claims 1 to 3, further comprising one or more additional polymer layers. **Claim 5** The manufacturing method according to any one of claims 1 to 4, wherein the polymer volume hologram is disposed on a second substrate. **Claim 6** The manufacturing method according to any one of claims 1 to 4, further comprising a second substrate. **Claim 7** The manufacturing method according to any one of claims 3 to 6, wherein the low refractive index compound in the bonding layer is different from the low refractive index compound in the polymer volume hologram. **Claim 8** The manufacturing method according to any one of claims 1 to 7, further comprising a polymer film adjacent to the bonding layer, wherein the polymer film is disposed between the first polymer layer and the bonding layer. **Claim 9** The manufacturing method according to any one of claims 3 to 8, wherein the bonding layer contains a low refractive index compound having a concentration within the range of -25 to +25 weight percent of the concentration of the low refractive index compound in the polymer volume hologram. **Claim 10** The manufacturing method according to any one of claims 1 to 9, wherein the bonding layer contains a total amount of the low refractive index compound within the range of more than 0 to less than 50 weight percent of the laminated structure. **Claim 11** The manufacturing method according to any one of claims 1 to 10, wherein the bonding layer comprises a polymer or elastomer selected from polyurethane, poly(vinyl acetal) such as poly(vinyl butyral), ethylene vinyl acetate copolymer, polyvinyl alcohol, cellulose ester, polyolefin elastomer, acrylic resin, polysiloxane and ionomer, or a blend of polymers or elastomers.

12. The manufacturing method according to any one of claims 3 to 11, wherein the low refractive index compound in the bonding layer is selected so as to have a refractive index within the range of -0.1 to +0.1 of the refractive index of the low refractive index compound in the polymer volume hologram.

13. The polymer film prevents the movement of the low refractive index compound from the bonding layer and / or the polymer volume hologram to the polymer layer. The manufacturing method according to any one of claims 8 to 12.

14. The manufacturing method according to any one of claims 1 to 13, wherein the bonding layer further comprises an adhesion promoter.

15. At least a part of the polymer layer has at least one of: a tapered intermediate layer, acoustic regulation and sound absorption characteristics, or an element that selectively blocks a part of the electromagnetic spectrum, or the polymer layer contains at least one of the following: a dye, a colorant, a pigment, a particle, an infrared or sunlight absorber.

16. The manufacturing method according to any one of claims 1 to 15, wherein the low refractive index compound comprises at least two different low refractive index compounds.

17. The manufacturing method according to claim 1, wherein the polymer volume hologram comprises a patterned or unpatterned photosensitive polymer film, and the polymer volume hologram does not contain a low refractive index compound before the assembly step.

18. Providing a first polymer layer, a bonding layer containing a low refractive index compound, a polymer volume hologram, and a second polymer layer; assembling the first polymer layer, the bonding layer, the polymer volume hologram, and the second polymer layer to form an assembly, wherein the polymer volume hologram is between the bonding layer and the second polymer layer; providing at least a first substrate; and laminating the assembly and at least the first substrate to form a laminated structure, wherein the optical regulation characteristics of the polymer volume hologram are greater than 70% of the original optical regulation characteristics of the polymer hologram before assembly in at least one wavelength range after lamination and equilibration of the low refractive index compound with the bonding layer, and the laminated structure has a low refractive index compound level distributed within the polymer volume hologram.

19. The manufacturing method according to any one of claims 1 to 18, wherein the optical regulation characteristics of the polymer volume hologram after equilibration of the low refractive index compound with the bonding layer in lamination are greater than 100% of the magnitude of the original optical regulation characteristics of the polymer hologram before assembly in at least one wavelength range.

20. A laminated structure produced by the manufacturing method according to any one of claims 1 to 19.

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