EP4359210A1

EP4359210A1 - Laminated pane having a diffusely reflecting element and an electrochromic functional element

Info

Publication number: EP4359210A1
Application number: EP22734273.0A
Authority: EP
Inventors: Michele CAPPUCCILLI; Florence JACQUES; Cecile Ozanam; Patrick Gayout
Original assignee: Saint Gobain Glass France SAS; Compagnie de Saint Gobain SA
Current assignee: Saint Gobain Glass France SAS; Compagnie de Saint Gobain SA
Priority date: 2021-06-24
Filing date: 2022-06-15
Publication date: 2024-05-01
Also published as: WO2022268606A1; CN115734874A

Abstract

The invention relates to a laminated pane (100), at least comprising an outer pane (1), which has an outer surface (I) and an inner surface (II), an electrochromic functional element (2), a first laminating layer (3), a diffusely reflecting element (4), a second laminating layer (5) and an inner pane (6) which has an outer surface (III) and an inner surface (IV). The diffusely reflecting element (4) is arranged between the outer pane (1) and the inner pane (6), the first laminating layer (3) is arranged between the outer pane (1) and the diffusely reflecting element (4), the second laminating layer (5) is arranged between the inner pane (6) and the diffusely reflecting element (4), and the electrochromic functional element (2) is arranged between the outer pane (1) and the first laminating layer (3). The diffusely reflecting element (4) completely overlaps the electrochromic functional element (2).

Description

COMPOSITE LENS WITH DIFFUSE REFLECTIVE ELEMENT AND ELECTROCHROMIC FUNCTIONAL ELEMENT

The invention relates to a laminated pane which has a combination of an electrochromic functional element and a diffusely reflecting element, a projection arrangement, a method for producing the laminated pane and its use.

The incorporation of diffusely reflecting elements in laminated glass, which are transparent as such and serve as a projection surface for displaying information, is known. The diffusely reflecting elements can be used in projection arrangements, such as in head-up displays, as a projection surface in laminated glass. A head-up display is a display system that allows the viewer to maintain their line of sight because the visual information is projected into their field of view. Projectors are used as the imaging unit, which project the image onto the projection element.

Diffuse reflection is conceptually understood as non-directional reflection. On a diffusely reflecting element, for example, an image from a projector directed from the interior of a vehicle onto the inner pane of the vehicle glazing is displayed, with the diffusely reflecting element showing a real image in the plane of the laminated pane. A real image differs from a virtual image, the virtual image being in a different plane than the projection plane and the real image being shown in the projection plane.

For example, substrates with liquid crystal coatings, materials with reflective functions, e.g., multilayer optical films, or others can be used as diffusely reflecting elements. Substrates with a structured surface are also possible, e.g. a plastic or a glass with a structured surface that has a reflective coating.

The function of a transparent screen based on cholesteric crystals is described, for example, in US 2018/0052264 A1, WO 2018/169095 A1 and JP2018180122. WO 2019/242915 A1 discloses a method for producing a laminated pane with a polarization-selective coating based on liquid crystals in a cholesteric phase.

Transparent layer elements with diffuse reflection properties based on structured substrates made of polymethyl methacrylate (PMMA) or glass are described, for example, in WO 2018/109375 A1, WO 2015/063418 A1 and WO 2018142050 A1. The transparent layer elements can serve as diffusely reflecting elements. EP 3 457 210 A1 discloses an image projection structure based on a transparent layer with an irregular surface on which a reflection layer is arranged.

When designing a projection arrangement, care must be taken to ensure that the projector has a correspondingly high output so that the projected image has sufficient brightness, especially when sunlight is incident, and can be easily recognized by the viewer. This requires a certain size of the projector and is associated with a corresponding power consumption and operational heat development.

In addition, with projection devices such as head-up displays, it is difficult to protect users' privacy since the projection screens used are transparent from both sides. Pedestrian safety must also be ensured by avoiding glare.

JP 2017090617 A discloses the combination of a display element with a dimmable element in order to protect user privacy.

CN 111487831 A discloses a projection arrangement in which an electrochromic element is arranged in front of the display element when viewed from the viewer in order to be able to hide the display element when the projector is switched off.

EP 3 825 765 A1 discloses a laminated pane with a reflective screen in which a light control layer is arranged behind the reflective layer as seen from the viewer.

There is a need for improvement in the contrast of images displayed by diffuse reflective elements contained in laminated glasses, and in the privacy of users and the prevention of glare to outside pedestrians.

The object of the present invention is to provide an improved laminated pane with a diffusely reflecting element.

The object of the present invention is solved by a laminated pane according to independent claim 1 . The invention also relates to a projection arrangement, a method for producing the composite pane and the use of the composite pane, according to the further independent claims. Preferred embodiments emerge from the dependent claims.

The invention relates to a laminated pane at least comprising an outer pane with an outer surface and an inner surface, an electrochromic functional element, a first laminating layer, a diffusely reflecting element, a second laminating layer and an inner pane with an outer surface and an inner surface.

In the laminated pane according to the invention, the diffusely reflecting element is arranged between the outer pane and the inner pane, the first laminating layer is arranged between the outer pane and the diffusely reflecting element, the second laminating layer is arranged between the inner pane and the diffusely reflecting element and the electrochromic functional element is between the outer pane and the first laminating layer.

According to the invention, the diffusely reflecting element completely overlaps with the electrochromic functional element.

Due to the fact that the diffusely reflecting element is arranged between the outer pane and the inner pane, the first laminating layer is arranged between the outer pane and the diffusely reflecting element, the second laminating layer is arranged between the inner pane and the diffusely reflecting element and the electrochromic functional element is arranged between the outer pane and the first laminating layer is arranged, the diffusely reflecting element is thus arranged spatially in front of the electrochromic functional element in the viewing direction from the inner pane to the outer pane.

The outer pane and the inner pane each have an outside surface, i.e. an outer surface, and an interior side surface, i.e. an inner surface, as described above, and a peripheral side edge extending therebetween. Within the meaning of the invention, the outer surface designates that main surface which is intended to face the external environment in the installed position. Within the meaning of the invention, inner surface designates that main surface which is intended to face the interior in the installed position. The inner surface of the outer pane and the outer surface of the inner pane face each other in the laminated pane according to the invention.

The surfaces of the disks are typically designated as follows: The outside surface of the outer pane is referred to as side I. The surface of the outer pane on the interior side is referred to as side II. The outside surface of the inner pane is referred to as Side III. The interior surface of the inner pane is referred to as side IV.

If the laminated pane is intended to separate an interior space from the outside environment in a window opening of a vehicle or a building, the inner pane within the meaning of the invention refers to the pane facing the interior (vehicle interior). The outer pane refers to the pane facing the outside environment.

When describing an element A as completely overlapping an element B, it is meant for the purposes of the invention that the orthogonal projection from element A to the surface plane of element B is located entirely within element B.

When looking through the laminated pane perpendicularly, the diffusely reflecting element is thus arranged completely in the area in which the electrochromic functional element is arranged.

The first laminating layer and the second laminating layer can independently be a thermoplastic interlayer or an optically clear adhesive (OCA). The first laminating layer and the second laminating layer can independently be, for example, polyvinyl butyral (PVB), ethylene vinyl acetate, polyurethane, polypropylene, polyacrylate, polyethylene, polycarbonate, polymethyl methacrylate, polyvinyl chloride, polyacetate resin, casting resin, acrylate, fluorinated ethylene propylene, polyvinyl fluoride and/or ethylene tetrafluoroethylene and/or contain or consist of a mixture and/or a copolymer thereof.

The first laminating layer and the second laminating layer particularly preferably contain ethylene vinyl acetate or polyvinyl butyral, very particularly preferably polyvinyl butyral.

In a preferred embodiment, the electrochromic functional element is designed as a coating on the inner surface of the outer pane.

Thus, the invention also includes a composite pane at least comprising an outer pane with an outer surface and an inner surface, an electrochromic functional element, a first laminating layer, a diffusely reflecting element, a second laminating layer and an inner pane with an outer surface and an inner surface, the diffusely reflecting element between the outer pane and the inner pane is arranged, the first laminating layer is arranged between the outer pane and the diffusely reflecting element, the second laminating layer is arranged between the inner pane and the diffusely reflecting element, the electrochromic functional element is designed as a coating on the inner surface of the outer pane and the diffusely reflecting element is completely covered with the electrochromic functional element overlapped.

It goes without saying that in this embodiment too the diffusely reflecting element is spatially arranged in front of the electrochromic functional element in the viewing direction from the inner pane to the outer pane.

In an alternative preferred embodiment, the composite pane according to the invention additionally comprises a third lamination layer, which is arranged between the electrochromic functional element and the outer pane. In this embodiment, the electrochromic functional element is thus arranged between the third laminating layer and the first laminating layer, adjoining the first laminating layer and the third laminating layer.

The invention therefore also comprises a laminated pane at least comprising an outer pane with an outer surface and an inner surface, a third lamination layer, an electrochromic functional element, a first lamination layer, a diffusely reflecting element, a second lamination layer and an inner pane with an outer surface and an inner surface, the diffusely reflecting element is arranged between the outer pane and the inner pane, the first laminating layer is arranged between the outer pane and the diffusely reflecting element, the second laminating layer is arranged between the inner pane and the diffusely reflecting element, the electrochromic functional element between the outer pane and the first laminating layer is arranged, the third laminating layer is arranged between the outer pane and the electrochromic functional element and the diffusely reflecting element completely overlaps with the electrochromic functional element.

Preferably, the third laminating layer is a thermoplastic interlayer or an optically clear adhesive (OCA). The third laminating layer can be, for example, polyvinyl butyral (PVB), ethylene vinyl acetate, polyurethane, polypropylene, polyacrylate, polyethylene, polycarbonate, polymethyl methacrylate, polyvinyl chloride, polyacetate resin, casting resin, acrylate, fluorinated ethylene contain or consist of propylene, polyvinyl fluoride and/or ethylene-tetrafluoroethylene and/or a mixture and/or a copolymer thereof.

The third laminating layer particularly preferably contains ethylene vinyl acetate or polyvinyl butyral, very particularly preferably polyvinyl butyral.

The diffusely reflective element is generally transparent. It serves as a projection surface for displaying visual information. The visual information or light is thrown onto the diffusely reflecting element by an imaging unit, also referred to as a projector.

Such diffusely reflecting elements and their mode of operation are known per se to a person skilled in the art. In particular, the diffusely reflecting element shows a reflection in the visible spectrum, with a locally different refractive index usually being present than with glass or PVB.

For example, the diffusely reflective element includes a diffusely reflective internal surface with a diffusely reflective coating. The diffusely reflecting coating preferably comprises nanoparticles or microparticles such as silicon dioxide particles, polymeric particles or liquid crystals. Alternatively, metal or metal oxide particles can also be used. In particular, the nanoparticles or microparticles mentioned have a spherical shape and/or are transparent or translucent. In particular, diffusely reflecting elements with a diffusely reflecting coating comprising titanium oxide particles (TiOx particles) or silver particles have proven to be advantageous. In the same way, diffusely reflecting elements with organic diffusely reflecting coatings containing cholesteric liquid crystals are very well suited to ensure good image quality. In a particularly preferred embodiment, diffusely reflecting elements comprise cholesteric liquid crystals oriented in a matrix. A possible example of a diffusely reflecting element is described in WO 2017/204103 A1, the element comprising randomly dispersed cholesteric liquid crystal droplets covered by a refractive index-matched layer. The cholesteric liquid crystal droplets essentially have the shape of a hemisphere, the radius of which depends on the contact angle between the film and the droplet. A wavelength selectivity of the diffusely reflecting element is also possible, as described for example in WO 2016/175183 A1.

If one surface of the diffusely reflective element comprises a random nanostructure or microstructure, then preferably another surface of the diffusely reflective element is smooth. In a further preferred embodiment, the diffusely reflecting element comprises a structured plastic film, which comprises a plurality of structured surfaces and the properties of the diffusely reflecting element are determined via the incline of the contact areas between adjacent structured layers. Exemplary embodiments and methods for structuring the layers of the diffusely reflecting element are described in WO 2012/104547 A1. Compared to the particle-based diffusely reflecting elements, the structured diffusely reflecting elements often achieve less haze and a better luminance factor (also referred to as "screen gain").

Suitable diffusely reflecting elements are commercially available.

Diffusely reflecting elements preferably have a reflection of more than 30% in the visible range.

In a preferred embodiment, the diffusely reflecting element is formed as a substrate layer with a passive coating, as a transparent layer element with diffuse reflectivity, as a reflective substrate with structure, or as a substrate layer with reflective metallic coating.

In a particularly preferred embodiment, the diffusely reflective element comprises a substrate layer having a passive coating, and the passive coating is selected from a liquid crystal coating or a diffusely reflective coating. The liquid crystal coating is in particular a cholesteric liquid crystal coating.

The substrate layer can, for example, have a thickness in the range from 0.03 to 0.2 mm, preferably 0.05 to 0.2 mm, in particular when the functional coating is a liquid crystal coating, in particular a cholesteric liquid crystal coating.

The substrate layer preferably contains polyvinyl butyral (PVB), cellulose triacetate (TAC), polymethyl methacrylate (PMMA), ethylene-vinyl acetate copolymer (EVA), polyethylene terephthalate (PET), polyethylene (PE), polyamide (PA) or polycarbonate (PC). or consists of it. The substrate layer is designed in particular as a film.

The diffusely reflecting element preferably has a total thickness in the range from 0.035 to 0.3 mm, in particular when it is a liquid crystal display, preferably a cholesteric liquid crystal display. In one embodiment, the electrochromic functional element and/or the diffusely reflecting element extend over at least 5%, preferably over at least 10%, particularly preferably over at least 50%, especially over at least 90% of the surface of the laminated pane according to the invention. It goes without saying that the proviso also applies in these embodiments that the diffusely reflecting element completely overlaps with the electrochromic functional element.

The electrochromic functional element can also extend over the entire surface of the composite pane or essentially over the entire surface, i.e. the entire surface minus a peripheral edge area of, for example, 20 mm, which is usually covered by a frame-like dark masking print. A full-area or essentially full-area arrangement of the electrochromic functional element offers advantages in production.

In the embodiments in which the electrochromic functional element extends over the entire surface or essentially over the entire surface of the composite pane, the diffusely reflecting element can also extend over the entire surface or essentially over the entire surface of the composite pane. It goes without saying that the proviso also applies in these embodiments that the diffusely reflecting element completely overlaps with the electrochromic functional element.

In one embodiment of a laminated pane according to the invention, the diffusely reflecting element is arranged in an edge area of the laminated pane. This can be, for example, a lateral edge area, an upper edge area or a lower edge area.

In a preferred embodiment, the diffusely reflecting element is arranged congruently with the electrochromic functional element in the viewing direction from the inner pane to the outer pane. The diffusely reflecting element and the electrochromic functional element therefore have the same external dimensions.

In one embodiment, the external dimensions of the electrochromic functional element are greater than the external dimensions of the diffusely reflecting element.

It is understood that external dimensions mean the dimensions that determine the area of an element. The outer dimensions do not include the thickness of the electrochromic functional element and the diffusely reflecting element. The thickness of the electrochromic functional element and the diffusely reflecting element can differ, even if the outer dimensions of these are the same. In one embodiment, the outer pane and/or the first laminating layer and/or the third laminating layer are tinted or colored.

The outer pane and/or the first laminating layer and/or the third laminating layer are preferably tinted or colored black.

In the embodiments of a laminated pane according to the invention, in which the outer pane and/or the first laminating layer and/or the third laminating layer is tinted or tinted, the laminated pane has in the see-through area in which the electrochromic functional element is arranged while the electrochromic functional element is activated and is therefore in a dark state, in particular a light transmission of less than 6%, for example 0.6% or 0.3% and while the electrochromic functional element is not activated, in particular a light transmission of at least 6%, up to 70%, for example 10%

In the embodiments of a laminated pane according to the invention, in which the outer pane and/or the first laminating layer and/or the third laminating layer is neither tinted nor colored, the laminated pane has in the see-through area in which the electrochromic functional element is arranged while the electrochromic functional element is activated and is therefore in a dark state, in particular a light transmission of less than 15%, for example 1%, and while the electrochromic functional element is not activated, in particular a light transmission of more than 30% up to 70%, for example 31%.

The electrochromic functional element is an element which has switchable or controllable optical properties. The transmission of light can be actively influenced by applying an electrical voltage. Installed in the laminated pane, a user can, for example, switch the laminated pane from a transparent to a non-transparent state. Gradations between transparency and opacity (opaqueness) are also possible. Such electrochromic functional elements and their mode of operation are known per se to a person skilled in the art.

In the context of the present invention, "transparent" means a transmission for visible light of more than 30% and in particular of more than 60%, for example more than 70%. Correspondingly, "opaque" means a light transmission of less than 15%, preferably less than 10%, particularly preferably less than 5% and in particular 0%. Suitable electrochromic functional elements which the laminated pane according to the invention can have are known to the person skilled in the art. These can be constructed, for example, as disclosed in US Pat. No. 5,321,544, US Pat. No. 5,404,244, US Pat. No. 7,372,610 B2, US Pat.

The electrochromic functional element preferably includes in the following order:

- a first surface electrode,

- a working electrode,

- an electrolyte,

- a counter electrode and

- a second surface electrode.

The first surface electrode and the second surface electrode are intended to be electrically connected to a voltage source. All of the layers mentioned are preferably firmly connected to one another. All of the layers mentioned are preferably arranged congruently with one another.

The working electrode and the counter-electrode are capable of reversibly storing charges. The oxidation states of the working electrode in the stored and stored state differ in their coloring, with one of these states being transparent. The storage reaction can be controlled via the externally applied potential difference. The opaque color of the electrochromic functional element, which can be set via the electrical potential, is preferably set in a color range from blue to black, in particular the adjustable color is black. The electrical potential range for changing between opacity and transparency of the electrochromic functional element is preferably 0 V to 7 V and particularly preferably 0.5 V to 5 V.

The first surface electrode and the second surface electrode are preferably transparent and electrically conductive. They preferably contain at least one metal, one metal alloy or one transparent conducting oxide (transparent conducting oxide, TCO). The first flat electrode and the second flat electrode particularly preferably contain silver, gold, copper, nickel, chromium, tungsten, graphite, molybdenum and/or a transparent conductive oxide, preferably indium tin oxide (ITO), fluorine-doped tin oxide (Sn0 ₂ :F ), antimony-doped tin oxide, aluminum-doped zinc oxide, boron-doped zinc oxide, or gallium-doped zinc oxide.

If the first surface electrode and/or the second surface electrode are based on a metal, they preferably have a total layer thickness of 1 nm to 50 nm, preferably 2 nm to 30 nm, particularly preferably 3 nm to 15 nm. If the first surface electrode and/or the second surface electrode is based on a transparent conductive oxide, they preferably have a total thickness of 20 nm to 2 μm, particularly preferably 50 nm to 1 μm, very particularly preferably 100 nm to 600 nm and in particular from 300 nm to 500 nm. This achieves advantageous electrical contacting of the working electrode and counterelectrode and good horizontal conductivity of the layers.

If something is designed “on the basis” of a material, then it mainly consists of this material, in particular essentially of this material in addition to any impurities or dopings.

The total layer resistance of the first flat electrode and the second flat electrode is preferably 0.01 ohms/square to 100 ohms/square, particularly preferably ohms/square to 20 ohms/square, very particularly preferably 0.5 ohms/square to 5 ohms/square . In this area, a sufficiently large current flow between the electrodes of the electrochromic functional element is ensured, which enables optimal functioning of the working electrode and counter-electrode.

The working electrode can be based on an inorganic or organic material. The working electrode is preferably based on tungsten oxide, but can also be based on molybdenum, titanium or niobium oxide and mixtures thereof. The working electrode can also be based on polypyrrole, PEDOT (poly-3,4-ethylenedioxythiophene) and polyaniline and mixtures thereof. The counter-electrode can be formed, for example, on the basis of titanium oxide, cerium oxide, iron(III) hexacyanidoferrate(II/III) (Fe Fe(CN) ₆ ] ₃ ) and nickel oxide, as well as mixtures thereof. The electrolyte is ionically conductive and may be based on a layer of hydrated tantalum oxide and a layer of hydrated antimony oxide. Alternatively, the electrolyte can also be based on a polymer that contains lithium ions or be based on tantalum(V) oxide and/or zirconium(IV) oxide.

In an alternative embodiment, the electrochromic functional element contains no electrolyte, with the working electrode itself functioning as the electrolyte. For example, depending on the oxidation state, tungsten oxide can assume the function of an electrolyte. Such embodiments are disclosed, for example, in US 2014/0022621 A1. Particular reference is made to FIG. 4F of US 2014/0022621 A1. In a very special embodiment of the invention, the electrochromic functional element also includes a first film and a second film. The first surface electrode is arranged on the first foil with a surface facing away from the working electrode, and the second surface electrode is arranged on the second foil with a surface facing away from the counter-electrode. The first film and/or the second film are preferably transparent. The first film and/or the second film are preferably based on polyethylene terephthalate. The total layer thickness of the electrochromic functional element is preferably from 0.2 mm to 0.5 mm for this embodiment.

In the activated state of the electrochromic functional element, the transparency of the electrochromic functional element is reduced. Since the diffusely reflecting element is arranged spatially in front of the electrochromic functional element in the viewing direction from the inner pane to the outer pane, the projected image has sufficient brightness when the electrochromic functional element is activated, especially when sunlight is incident, and can be easily recognized by the viewer.

The laminated pane according to the invention solves the problem of the high contrast requirement of images generated on the laminated pane by using the principle of diffuse reflection in combination with an electrochromic functional element with which the optical properties of the pane can be controlled.

This achieves a higher contrast for the generated image when the transparency of the laminated pane is reduced with the aid of the electrochromic functional element. This drastically reduces the required projector power, which can also lead to a reduction in the size of the projector and thus enables it to be used in a limited space, e.g. in cars. Because less light is required, less heat is generated. In addition, the energy consumption of the projector decreases, which can have a positive effect on the range of electric vehicles in particular.

In addition, the invention enables protection of the privacy of users of image displays based on diffusely reflective elements. By adjusting the optical property, ie the transparency, of the pane using the electrochromic functional element, pedestrians outside the vehicle cannot see the images displayed on the composite pane. In addition, the combination of an electrochromic functional element and a diffusely reflecting element prevents pedestrians from being dazzled by the light beams let through by the projector. The invention represents a combination of an electrochromic functional element and a diffusely reflecting element in a laminated glass. This combination enables a privacy function for display applications based on the principle of diffusely reflecting elements when the electrochromic functional element is activated and thus the amount of the transmitted light is reduced. This helps exploit diffuse reflections from the diffuse reflective element for applications such as transparent screens that are not visible to people outside the car. In addition, a switchable background in the form of an electrochromic functional element increases the contrast of the generated image. This helps to reduce projector requirements and/or increase the viewable area.

The outer pane and the inner pane can be flat or curved panes. The panes can be made of inorganic glass and/or organic glass (plastic). The outer pane and the inner pane can, for example, independently of one another, be made of flat glass, quartz glass, borosilicate glass, soda-lime glass, aluminosilicate glass, polycarbonate and/or polymethacrylate. The outer pane and the inner pane are preferably made of soda-lime glass. The outer pane and the inner pane have, for example, independently of one another, a thickness in the range from 0.4 to 5.0 mm, for example 1 to 3 mm, more preferably 1.6 to 2.5 mm.

The outer pane and/or the inner pane can have other suitable coatings known per se, e.g. non-stick coatings, tinted coatings, anti-reflective coatings, anti-scratch coatings or low-E coatings.

As described above, the laminated pane according to the invention comprises a first laminating layer, a second laminating layer and optionally a third laminating layer. The laminating layers may be the same or different in composition and/or thickness. The laminating layers can be formed by commercially available laminating films. They are used for bonding or laminating the components of the laminated pane. The outer pane and the inner pane are connected to one another by the laminating layers and the electrochromic functional element and the diffusely reflecting element are laminated into the composite pane.

The thickness of the first laminating layer, the second laminating layer and the third laminating layer can independently be between 30 µm (microns) and 2 mm, for example 50 µm, 0.38 mm or 0.76 mm. It is particularly advantageous if the first laminating layer, ie the laminating layer arranged between the electrochromic functional element and the diffusely reflecting element, has a thickness in the range from 30 to 200 μm, preferably 30 to 150 μm, more preferably 30 to 100 μm . In this way, the distance between the functional element and the diffusely reflecting element can be kept small, as a result of which ghost images can be avoided. The first laminating layer and the second laminating layer, independently of one another, preferably have a thickness in the range from 30 to 200 μm, for example 50 μm. If present, the third laminating layer preferably has a thickness in the range of 0.3 to 1 mm.

In the embodiments in which the electrochromic functional element does not extend over the entire surface of the composite pane, the composite pane can optionally have a fourth lamination layer with a recess in which the electrochromic functional element is accommodated. In these embodiments, the electrochromic functional element is thus surrounded by the fourth laminating layer in the manner of a frame.

In the embodiments in which the diffusely reflecting element does not extend over the entire surface of the composite pane, the composite pane can optionally have a fifth lamination layer with a recess in which the diffusely reflecting element is accommodated. In these embodiments, the diffusely reflecting element is thus surrounded by the fifth laminating layer in the manner of a frame.

The fourth laminating layer and the fifth laminating layer can independently be a thermoplastic intermediate layer. They can be, independently of one another, e.g /or contain or consist of a copolymer thereof.

The thickness of the fourth laminating layer corresponds to the thickness of the electrochromic functional element and the thickness of the fifth laminating layer corresponds to the thickness of the diffusely reflecting element.

The invention also relates to a projection arrangement comprising a composite pane according to the invention and at least one projector which is directed from the inside onto the diffusely reflecting element in order to generate a real image in the plane of the composite pane. The preferred configurations of the composite pane according to the invention described above also apply correspondingly to the projection arrangement comprising a composite pane according to the invention.

The invention also relates to a method for producing a composite pane according to the invention as described above, the method comprising the following steps: a) providing an outer pane with an outer surface and an inner surface, an electrochromic functional element, a first laminating layer, a diffusely reflecting element, a second Laminating layer and an inner pane with an outer surface and an inner surface, b) forming a layer stack in which the diffusely reflecting element is arranged between the outer pane and the inner pane, the first lamination layer is arranged between the outer pane and the diffusely reflecting element, the second lamination layer is between the inner pane and the diffusely reflecting element is arranged, the electrochromic functional element is arranged between the outer pane and the first laminating layer and the diffusely reflecting element completely with the electrochromic Functional element overlaps, c) connecting the stack of layers by lamination.

Because a layer stack is formed in step b), in which the diffusely reflecting element is arranged between the outer pane and the inner pane, the first laminating layer is arranged between the outer pane and the diffusely reflecting element, and the second laminating layer is arranged between the inner pane and the diffusely reflecting element Element is arranged and the electrochromic functional element is arranged between the outer pane and the first laminating layer, the diffusely reflecting element is thus spatially arranged in front of the electrochromic functional element in the layer stack in the direction of view from the inner pane to the outer pane.

The lamination causes the components to be bonded together to form the laminated pane. Lamination is generally done in an autoclave.

If the composite pane is to be curved, the outer pane and the inner pane are preferably subjected to a bending process before lamination. The outer pane and the inner pane are preferably bent congruently together (ie at the same time and using the same tool), because this changes the shape of the panes for the later lamination are optimally matched to each other. Typical temperatures for glass bending processes are 500°C to 700°C, for example.

The layer stack can be laminated using common lamination processes. For example, so-called autoclave processes can be carried out at an increased pressure of about 10 bar to 15 bar and temperatures of 90° C. to 100° C. for about 2 hours. Alternatively, autoclave-free processes are also possible. Known vacuum bag or vacuum ring methods work, for example, at about 200 mbar and 80°C to 100°C. The stack of layers can also be pressed in a calender between at least one pair of rollers to form a composite pane. Plants of this type are known for the production of discs and normally have at least one heating tunnel in front of a pressing plant. The temperature during the pressing process is, for example, from 40°C to 100°C. Combinations of calender and autoclave processes have proven particularly useful in practice. Alternatively, vacuum laminators can be used. These consist of one or more chambers that can be heated and evacuated, in which the first pane and the second pane are laminated within about 60 minutes, for example, at reduced pressures of 0.01 mbar to 800 mbar and temperatures of 80 °C to 100 °C.

The preferred configurations of the laminated pane according to the invention described above also apply correspondingly to methods for producing a laminated pane according to the invention.

The invention also relates to the use of a composite pane according to the invention as interior or exterior glazing in a vehicle or a building, in particular as a vehicle pane in means of transport for traffic on land, in the air or on water, in particular in motor vehicles.

The composite pane according to the invention as described above is preferably mounted in a vehicle or a building. The invention therefore also relates to a vehicle or structure in which a composite pane according to the invention is mounted as described above.

In a preferred embodiment, the vehicle or structure is a vehicle selected from passenger vehicles or transport vehicles, such as buses, coaches, trains, trams, airplanes or ships. In a preferred embodiment, the vehicle or structure is a structure, with the laminated pane being mounted as a window pane or partition pane. The cutting disc can serve as a partition or display device.

In a preferred embodiment, the composite pane according to the invention is a rear window, side window, windshield or roof window, in particular a roof window or side window of a vehicle.

The invention is explained in more detail below with the aid of exemplary embodiments based on the attached figures, which are not intended to restrict the invention in any way. The accompanying figures are schematic representations and are not drawn to scale.

Show it:

1 shows the cross section of an embodiment of a laminated pane according to the invention,

2 shows the cross section of a further embodiment of one according to the invention

laminated pane,

3 shows a plan view of an embodiment of a laminated pane according to the invention,

4 shows the cross section of an embodiment of the composite pane shown in FIG. 3 along the section line X'-X,

FIG. 5 shows the cross-section of a further embodiment of that shown in FIG

composite pane along the cutting line X'-X,

6 shows a plan view of a further embodiment of one according to the invention

laminated pane,

Fig. 7 shows the cross section of an embodiment of the laminated pane shown in Fig. 6 along the section line Y'-Y,

FIG. 8 shows the cross-section of a further embodiment of that shown in FIG

composite pane along the line of intersection Y'-Y,

9 shows the cross section of an embodiment of a diffusely reflecting element,

Fig. 10 shows the cross-section of another embodiment of a diffusely reflecting element.

Fig. 11 shows the cross-section of another embodiment of a diffusely reflecting element. Fig. 12 shows the cross-section of another embodiment of a diffusely reflecting element. Fig. 13 shows a flow diagram of the method according to the invention.

Fig. 1 shows the cross section of an embodiment of a composite pane 100 according to the invention. In the embodiment shown in Fig. 1, the composite pane 100 comprises an outer pane 1 with an outer surface I and an inner surface II, an electrochromic functional element 2, a first laminating layer 3, a diffuse reflective element 4, a second laminating layer 5 and an inner pane 6 having an outer surface III and an inner surface IV.

The electrochromic functional element 2 is designed as a coating on the inner surface II of the outer pane 1 and is constructed, for example, as described in US Pat. No. 7,372,610 B2.

The diffusely reflecting element 4 is arranged between the outer pane 1 and the inner pane 6, the first laminating layer 3 is arranged between the electrochromic functional element 2 and the diffusely reflecting element 4 and the second laminating layer 5 is arranged between the diffusely reflecting element 4 and the inner pane 6 . Thus, in the embodiment shown in FIG. 1, the laminated pane 100 has the following sequence of layers:

Outer pane 1 - electrochromic functional element 2 - first laminating layer 3 - diffusely reflecting element 4 - second laminating layer 5 - inner pane 6

In the embodiment shown in Fig. 1, the electrochromic functional element 2 and the diffusely reflecting element 4 extend over the entire surface of the laminated pane 100.

The outer pane 1 consists, for example, of soda-lime glass and is 2.1 mm thick. The inner pane 6 consists, for example, of soda-lime glass and is 1.6 mm thick.

The first laminating layer 3 and the second laminating layer 5 are, for example, thermoplastic intermediate layers and consist, for example, of polyvinyl butyral (PVB) and are each 0.38 mm thick.

In the embodiment shown in FIG. 1, the diffusely reflecting element can be constructed, for example, as shown in FIGS. Fig. 2 shows the cross section of a further embodiment of a composite pane 100 according to the invention. In the embodiment shown in Fig first laminating layer 3, a diffusely reflecting element 4, a second laminating layer 5 and an inner pane 6 having an outer surface III and an inner surface IV.

The diffusely reflecting element 4 is arranged between the outer pane 1 and the inner pane 6, the electrochromic functional element 2 is arranged between the outer pane 1 and the diffusely reflecting element 4, the first laminating layer 3 is arranged between the electrochromic functional element 2 and the diffusely reflecting element 4 , the third laminating layer 7 is arranged between the electrochromic functional element 2 and the outer pane 1 and the second laminating layer 5 is arranged between the diffusely reflecting element 4 and the inner pane 6 .

Thus, in the embodiment shown in FIG. 2, the laminated pane 100 has the following sequence of layers:

Outer pane 1 - third laminating layer 7 - electrochromic functional element 2 - first laminating layer 3 - diffusely reflecting element 4 - second laminating layer 5 - inner pane 6

In the embodiment shown in Fig. 2, the electrochromic functional element 2 and the diffusely reflecting element 4 extend over the entire surface of the laminated pane 100.

In this exemplary embodiment, the electrochromic functional element 2 comprises, for example, in the following order: a first PET film, a first surface electrode, a working electrode, an electrolyte, a counter electrode, a second surface electrode and a second PET film. The surface electrodes are, for example, thin layers of an electrically conductive material Materials containing indium tin oxide. The ion-conductive electrolyte is constructed, for example, on the basis of a layer of hydrated tantalum oxide and a layer of hydrated antimony oxide. The working electrode and the counter-electrode are constructed on the basis of an organic polymer, for example.

The outer pane 1 consists, for example, of soda-lime glass and is 2.1 mm thick. The inner pane 6 consists, for example, of soda-lime glass and is 1.6 mm thick. The first laminating layer 3 and the second laminating layer 5 are, for example, thermoplastic intermediate layers and consist, for example, of polyvinyl butyral (PVB) and are each 0.38 mm thick. The third laminating layer 7 is, for example, a thermoplastic intermediate layer and is also 0.38 mm thick.

In the embodiment shown in FIG. 2, the diffusely reflecting element can be constructed, for example, as shown in FIGS.

FIG. 3 shows a plan view of an embodiment of a composite pane 100 according to the invention. In the embodiment shown in FIG. 3, the composite pane 100 is a roof pane, for example. The area in which the electrochromic functional element 2 is arranged is identified by the reference symbol B in FIG. 3 . The dashed line marks the peripheral edge of the electrochromic functional element 2. In FIG. 3, the area in which the diffusely reflecting element 4 is arranged is marked with the reference symbol A. The dotted line marks the peripheral side edge of the diffusely reflecting element 4. In the embodiment shown in FIG. 3, the electrochromic functional element 2 and the diffusely reflecting element 4 are arranged congruently in the viewing direction from the inner pane to the outer pane.

FIG. 4 shows the cross section of an embodiment of the laminated pane shown in FIG. 3 along the section line X'-X.

The embodiment of a laminated pane 100 shown in cross section in FIG. 4 differs from the embodiment shown in FIG. but over the entire outer pane 1 minus a peripheral edge area of, for example, 20 mm.

Likewise, the diffusely reflecting element 4 does not extend over the entire composite pane 100, but rather over the entire composite pane 100 minus a peripheral edge region of, for example, 20 mm.

In addition, in contrast to the embodiment shown in FIG. 1 , the laminated pane 100 in the embodiment shown in FIG. 4 has a fourth lamination layer 12 and a fifth lamination layer 13 . The fourth laminating layer 12 has a recess in in which the electrochromic functional element 2 is accommodated, and the fifth laminating layer 13 has a recess in which the diffusely reflecting element 4 is accommodated.

The electrochromic functional element 2 is thus surrounded by the fourth laminating layer 12 like a frame in the embodiment shown in FIG. 4 and the diffusely reflecting element 4 is surrounded like a frame by the fifth laminating layer 13 in the embodiment shown in FIG.

The fourth laminating layer 12 and the fifth laminating layer 13 are made of polyvinyl butyral (PVB), for example. The thickness of the fourth laminating layer 12 corresponds to the thickness of the electrochromic functional element 2 and the thickness of the fifth laminating layer 13 corresponds to the thickness of the diffusely reflecting element 4. The use of a fourth laminating layer 12 and a fifth laminating layer 13 is optional. It is also possible for the first laminating layer 3 or the second laminating layer 5 to also laterally surround the electrochromic functional element 2 or the diffusely reflecting element 4 after the lamination.

FIG. 5 shows the cross section of a further embodiment of the laminated pane shown in FIG. 3 along the section line X'-X.

The embodiment of a composite pane 100 shown in cross section in FIG. 5 differs from the embodiment shown in FIG. 2 only in that the electrochromic functional element 2 does not extend over the entire outer pane 1, but rather over the entire outer pane 1 minus a peripheral one Edge area of 20 mm, for example.

Likewise, the diffusely reflecting element 4 does not extend over the entire outer pane 1, but rather over the entire outer pane 1 minus a peripheral edge area of, for example, 20 mm.

In addition, in contrast to the embodiment shown in FIG. 2 , the laminated pane 100 in the embodiment shown in FIG. 5 has a fourth lamination layer 12 and a fifth lamination layer 13 . The fourth laminating layer 12 has a gap in which the electrochromic functional element 2 is accommodated, and the fifth laminating layer 13 has a gap in which the diffusely reflecting element 4 is accommodated.

In the embodiment shown in FIG. 5, the electrochromic functional element 2 is thus surrounded in the manner of a frame by the fourth laminating layer 12 and is diffusely reflective In the embodiment shown in FIG. 5, element 4 is surrounded by the fifth laminating layer 13 in the manner of a frame.

The fourth laminating layer 12 and the fifth laminating layer 13 are made of polyvinyl butyral (PVB), for example. The thickness of the fourth laminating layer 12 corresponds to the thickness of the electrochromic functional element 2 and the thickness of the fifth laminating layer 13 corresponds to the thickness of the diffusely reflecting element 4. The use of a fourth laminating layer 12 and a fifth laminating layer 13 is optional. It is also possible for the first laminating layer 3 or the laminating layer 5 or the third laminating layer 7 to also laterally surround the electrochromic functional element 2 or the diffusely reflecting element 4 after the lamination.

FIG. 6 shows a plan view of an embodiment of a composite pane 100 according to the invention. In the embodiment shown in FIG. 6, the composite pane 100 is a windshield, for example. The area in which the electrochromic functional element 2 is arranged is identified by the reference symbol B in FIG. 6 . The dashed line marks the peripheral edge of the electrochromic functional element 2. In FIG. 6, the area in which the diffusely reflecting element 4 is arranged is marked with the reference symbol A. The dotted line characterizes the circumferential side edge of the diffusely reflecting element 4. The laminated pane 100 has an upper edge O, a lower edge U and two side edges S. In the embodiment shown in FIG. 6 , the electrochromic functional element 2 and the diffusely reflecting element 4 are arranged congruently in the lower quarter of the laminated pane 100 in the viewing direction from the inner pane to the outer pane.

FIG. 7 shows the cross section of an embodiment of the laminated pane shown in FIG. 6 along the section line Y'-Y.

The embodiment of a composite pane 100 shown in cross section in FIG. 7 differs from the embodiment shown in FIG extends peripheral edge area, but is arranged in an edge area, more precisely in an area in the lower quarter of the composite pane 100 is arranged, which is spaced from the lower edge U and the side edges S, for example 20 mm. Likewise, the diffusely reflecting element 4 does not extend over the entire outer pane 1 minus a peripheral edge area, but is arranged in an edge area, more precisely in an area in the lower quarter of the composite pane 100, which is separated from the lower edge U and the side edges S, for example 20 mm apart.

FIG. 8 shows the cross section of a further embodiment of the laminated pane shown in FIG. 6 along the section line Y'-Y.

The embodiment of a laminated pane 100 shown in cross section in FIG. 8 differs from the embodiment shown in FIG is arranged in an edge area, more precisely in an area in the lower quarter of the laminated pane 100, which is spaced from the lower edge U and the side edges S, for example 20 mm.

Likewise, the diffusely reflecting element 4 does not extend over the entire surface of the laminated pane 100 minus a peripheral edge area, but is arranged in an edge region, more precisely in an area in the lower quarter of the laminated pane 100, which consists of the lower edge U and the side edges S for example 20 mm apart.

Fig. 9 shows the cross section of an embodiment of a diffusely reflecting element 4. The diffusely reflecting element 4 comprises a substrate layer 8, with a passive coating 9, in particular a cholesteric liquid crystal coating, being applied to one side of the substrate layer 8, which serves as a projection surface for displaying the information serves. The overall thickness of the diffusely reflecting element 4 can be 0.05 mm, for example. The substrate layer 8 can be a substrate based on PVB, TAC, PMMA, EVA, PET, PE, PA or PC, for example.

10 shows the cross section of another embodiment of a diffusely reflecting element. 4. The diffusely reflecting element 4 comprises a substrate layer 8, with a reflective metallic coating 11 being applied to one side of the substrate layer 8, which serves as a projection surface for displaying the information. The overall thickness of the diffusely reflecting element 4 can be 0.05 mm, for example. The substrate layer 8 can be a substrate based on PVB, TAC, PMMA, EVA, PET, PE, PA or PC, for example. 11 shows the cross section of another embodiment of a diffusely reflecting element. 4. In the embodiment shown in FIG. 11, the diffusely reflecting element 4 is designed as a reflective substrate with a structure and comprises a substrate layer with a structured surface 10a, with a reflective coating 10b being applied to the structured surface. The substrate layer with a structured surface 10a is, for example, a substrate based on PMMA with a thickness of 70 μm, to which a TiO _x coating with a thickness of 60 nm is applied.

12 shows the cross-section of another embodiment of a diffusely reflecting element. 4. The embodiment shown in FIG. 12 differs from that shown in FIG. 11 only in that the surface of the substrate layer has a structured

Surface 10a is structured only in a partial area.

FIG. 13 shows a flow chart for visualizing the method according to the invention for producing a laminated pane according to the invention.

In a first step a), an outer pane 1 with an outer surface I and an inner surface II, an electrochromic functional element 2, a first laminating layer 3, a diffusely reflecting element 4, a second laminating layer 5 and an inner pane 6 with an outer surface III and an inner surface IV provided.

In a second step b), a stack of layers is formed in which the diffusely reflecting element 4 is arranged between the outer pane 1 and the inner pane 6, the first lamination layer 3 is arranged between the outer pane 1 and the diffusely reflecting element 4, the second lamination layer 5 is arranged between the inner pane 6 and the diffusely reflecting element 4 and the electrochromic functional element 2 is arranged between the outer pane 1 and the first laminating layer 3 , and the diffusely reflecting element 4 completely overlaps with the electrochromic functional element 2 . In a third step c), the stack of layers is connected by lamination. Example setup 1:

A laminated pane was produced, which is constructed as follows: clear glass 2.1 mm clear PVB 0.76 mm electrochromic functional element clear PVB 0.76 mm diffusely reflecting element clear PVB 0.76 mm clear glass 2.1 mm

This has a light transmission of 1% when the electrochromic functional element is switched dark and a light transmission of 31% when the electrochromic functional element is not switched dark.

Example setup 2:

A laminated pane was produced, which is structured as follows: dark glass 2.1 mm clear PVB 0.76 mm electrochromic functional element clear PVB 0.76 mm diffusely reflecting element clear PVB 0.76 mm clear glass 2.1 mm

This has a light transmission of 0.3% when the electrochromic functional element is switched dark and a light transmission of 9.6% when the electrochromic functional element is not switched dark. Reference List

1 outer pane

2 electrochromic functional element

3 first laminating layer 4 diffusely reflecting element

5 second layer of lamination

6 inner pane

7 third layer of lamination

8 substrate layer 9 passive coating

10a substrate layer with structured surface 10b reflective coating

11 reflective metallic coating

12 fourth laminating layer 13 fifth laminating layer

100 Composite Disc

A area A B area B

I Outer surface of the outer pane

II Inner surface of the outer pane

III Outer surface of the inner pane IV Inner surface of the inner pane

X'-X cutting line

Y'-Y intersection line

Claims

patent claims

1. Composite pane (100), at least comprising an outer pane (1) with an outer surface (I) and an inner surface (II), an electrochromic functional element (2), a first laminating layer (3), a diffusely reflective element (4), a second laminating layer (5), an inner pane (6) with an outer surface (III) and an inner surface (IV), the diffusely reflecting element (4) being arranged between the outer pane (1) and the inner pane (6), the first laminating layer (3) is arranged between the outer pane (1) and the diffusely reflecting element (4), the second laminating layer (5) is arranged between the inner pane (6) and the diffusely reflecting element (4), the electrochromic functional element (2) between the outer pane (1) and the first laminating layer (3) and the diffusely reflecting element (4) completely overlaps with the electrochromic functional element (2).

The laminated pane (100) of claim 1, wherein the first laminating layer (3) and the second laminating layer (5) are independently a thermoplastic interlayer or an optically clear adhesive (OCA).

3. Composite pane (100) according to claim 1 or 2, wherein the electrochromic functional element (2) is designed as a coating of the inner surface (II) of the outer pane (1).

4. Laminated pane (100) according to claim 1 or 2, additionally comprising a third laminating layer (7), wherein the third laminating layer (7) is arranged between the electrochromic functional element (2) and the outer pane (1) and preferably a thermoplastic intermediate layer or a is optically clear adhesive (OCA).

5. Laminated pane (100) according to any one of claims 1 to 4, wherein the diffusely reflecting element (4) as a substrate layer (8) with a passive coating (9), as a transparent layer element with diffuse reflectivity, as a reflective Substrate is formed with a structure or as a substrate layer (8) with a reflective metallic coating (11).

6. Composite pane (100) according to claim 5, wherein the diffusely reflecting element (4) comprises a substrate layer (8) having a passive coating (9), and the passive coating (9) is selected from a liquid crystal coating, in particular a cholesteric one liquid crystal coating, or a diffusely reflective coating.

7. Laminate (100) according to claim 6, wherein the substrate layer (8) polyvinyl butyral (PVB), cellulose triacetate (TAC), polymethyl methacrylate (PMMA), ethylene-vinyl acetate copolymer (EVA), polyethylene terephthalate (PET), polyethylene (PE), polyamide (PA) or polycarbonate (PC) contains or consists of.

8. Laminated pane (100) according to one of claims 1 to 7, wherein the electrochromic functional element (2) and/or the diffusely reflecting element (4) differ by at least 5%, preferably by at least 10%, particularly preferably by at least 50%. very particularly extend over at least 90% of the area of the laminated pane (100).

9. Composite pane (100) according to any one of claims 1 to 8, wherein the diffusely reflecting element (4) is arranged in an edge region of the composite pane (100).

10. Composite pane (100) according to one of claims 1 to 9, wherein the diffusely reflecting element (4) is arranged congruently with the electrochromic functional element (2) in the viewing direction from the inner pane (6) to the outer pane (1).

11. Composite pane (100) according to any one of claims 1 to 9, wherein the outer dimensions of the electrochromic functional element (2) are larger than the outer dimensions of the diffusely reflecting element (4).

12. Composite pane (100) according to any one of claims 1 to 11, wherein the outer pane (1) and/or the first laminating layer (3) and/or the third laminating layer (7) is tinted or colored.

13. Projection arrangement comprising a composite pane (100) according to one of claims 1 to 12 and at least one projector which is directed from the inside onto the diffusely reflecting element (4) to generate a real image in the plane of the composite pane (100).

14. The method for producing a composite pane (100) according to any one of claims 1 to 12, wherein at least a) an outer pane (1) with an outer surface (I) and an inner surface (II), an electrochromic functional element (2), a first laminating layer (3), a diffusely reflecting element (4), a second laminating layer (5) and an inner pane (6) with an outer surface (III) and an inner surface (IV) are provided, b) a layer stack is formed in which the diffuse reflective element (4) is arranged between the outer pane (1) and the inner pane (6), the first laminating layer (3) is arranged between the outer pane (1) and the diffusely reflecting element (4), the second laminating layer between the inner pane ( 6) and the diffusely reflecting element (4) is arranged and the electrochromic functional element (2) is arranged between the outer pane (1) and the first laminating layer (3), and the diffusely reflecting element (4) is complete g overlaps with the electrochromic functional element (2), c) the layer stack is connected by lamination.

15. Use of a laminated pane (100) according to one of claims 1 to 12 as interior glazing or exterior glazing in a vehicle or a building, in particular as a vehicle pane in means of transport for traffic on land, in the air or on water, in particular in passenger vehicles, buses ,

Coaches, trains, trams, planes or ships.