Illuminated Glazing Roof

Abstract

The present invention relates to a lighting vehicle glazing (3) having (i) an exterior glass pane (10) having an exterior surface (P1) and an interior surface (P2) and an edge, and (ii) an interior glass pane (11) having an exterior surface (P3) and an interior surface (P4) and an edge (110). (iii) The exterior glass pane (10) and the interior glass pane (11) are laminated together via at least a first plastic interlayer (14) having a thickness T1. The lighting vehicle glazing (3) further comprises (iv) a light-conducting plastic interlayer (12) in contact with the outer surface (P3) of the inner glass pane (11) and having a thickness T2 less than T1, the light-conducting plastic interlayer (12) configured to conduct light coupled into one of its end sides substantially joined to the inner glass pane (11), and (v) at least one light source (16) configured to couple light into at least one end side (122) of the light-conducting layer and / or into an end side (110) of the inner glass pane (11). According to the invention, the light-conducting plastic intermediate layer (12) comprises a thermoplastic intermediate layer (120) provided with a functional layer (121) having light-scattering particles applied to at least one surface of the thermoplastic intermediate layer (120) that is in contact with the outer surface (P3) of the inner glass pane (11), and the light-conducting plastic intermediate layer (12) comprises decoupling means (13) through which light emission of transmitted light from the light source (16) is brought to the top of at least one of the main surfaces of the light-conducting layer.

Description

[Technical field]

[0001] The present invention relates to an illumination glazing unit for a vehicle, and more particularly to an illumination glazing unit forming part of the roof of a motor vehicle. [Background technology]

[0002] Currently, automobile manufacturers are looking for lighting glazing that has a uniform diffusion of light and is aesthetically pleasing, and there is an increasing demand to add some pattern to the glazing on at least a portion of its surface, however, having a pattern can affect the uniformity of the lighting.

[0003] An interior light for vehicles is known from DE 10360729 C1, in which the interior light is integrated with a printed circuit board having light-emitting diodes and electronic circuits in a composite glass pane.

[0004] DE 102 04 359 A1 describes a device for illuminating a motor vehicle sunroof, but the structure of the device described in this document is rather complicated and leads to an increase in the thickness of the sunroof part, which inevitably leads to a reduction in the driver's head space and an increase in the vehicle weight.

[0005] DE 102012109900 describes illuminable glazing for automobile sunroofs having a light guide layer manufactured to have light scattering particles embedded therein or to have a physically modified surface.

[0006] However, a need remains for improved illuminable glazing. Summary of the Invention

[0007] One of the aims to be achieved is to define improved concepts for glazing which are relatively flexible in handling and allow simplified production sequences.

[0008] These objects are achieved by the vehicle glazing according to the invention as defined in claim 1. Further realizations are achieved by the subject matter respectively defined in the dependent claims.

[0009] The improved concept is based on the idea of ​​providing the individual components of the vehicle glazing with lighting functions separately and then combining them to form a composite using conventional manufacturing methods. As a result, the lighting function can be relatively easily combined with other functions such as thermal protection, including coatings, switchable films, touch functions, etc. Also, according to one object of the invention, the light source is provided separately and can be mounted without further steps to the composition, which also allows simple exchangeability of the light source, for example for maintenance purposes. The improved concept allows to reduce the manufacturing costs and even the storage costs of the individual components of the overall composition.

[0010] In one embodiment of the improved concept, the vehicle glazing comprises an exterior glass pane and an interior glass pane, for example made of tempered glass, at least a first plastic layer, a light-conductive layer in contact with the inner surface of the interior glass pane, and a light source. The light-conductive layer is configured to conduct light coupled in at one of its end sides and has decoupling means, through which light output of the conducted light is provided on at least one of its main surfaces. The light-conductive layer is substantially bonded to the pane. The light source is configured such that light is coupled in at at least one end side of the light-conductive layer. Furthermore, at least a first plastic interlayer is configured between the pane and the light-conductive layer, which has a lower refractive index than the interior glass pane. The at least a first plastic interlayer is implemented as a lamination layer. In some embodiments, the light-conductive layer has a thickness of T2.

[0011] A surface emission of light laterally coupled into the layer is made possible by the photoconductive layer with decoupling means. Due to at least the first plastic interlayer, for example, light guided in the photoconductive layer does not reach the refractive layer and is instead reflected back into the photoconductive layer. This results in particular in a relatively high light yield and a relatively good light transport in the photoconductive layer. By having the light deflected by the plastic interlayer, it can be broadened and diffused so as to reduce the problems created by a relatively direct illumination from a point source. The plastic interlayer may be substantially transparent, which may be neutral or clear in color, or it may be body-colored.

[0012] In addition to this, at least the first plastic interlayer prevents light from radiating through the exterior glass pane, i.e. for example preventing light from reaching the outside from inside the vehicle. The pane itself can be a conventional pane, which is not subject to light guiding or light emission.

[0013] A uniform optical impression can be achieved by means of a thermoplastic intermediate layer.

[0014] In one embodiment, at least the first plastic interlayer is preferably a polyvinyl butyral film, i.e., a PVB film. In some embodiments, the first plastic interlayer has a thickness of T1. In different embodiments, the thickness (T2) of the photoconductive layer is less than the thickness (T1) of the first plastic interlayer, i.e., T2 <T1である。

[0015] The exterior and interior glass panes may be flat soda-lime glass, especially float glass. One or both of the glass sheets may be clear glass, extra clear glass, or body-tinted glass. The glazing panel may be substantially transparent, especially when intended to be used in window applications. In this case, it may have, for example, a light transmittance (CIE Illuminant C) of 40%, 50%, 60%, or 70% or more and / or a haze level of 5%, 3%, or 2% or less. It may not be necessary and / or desirable for the panel to be substantially transparent, especially when intended for decorative and / or lighting purposes. In this case, it may have a light transmittance (CIE Illuminant C) of 20%, 10%, or 5% or less and / or a haze level of 30%, 40%, or 50% or more.

[0016] In one preferred embodiment, the inner glass pane is an extra clear glass pane.

[0017] The percentage of the surface of the photoconductive layer that is provided with the decoupling means can vary depending on the application from a small percentage up to a full surface embodiment, In one preferred embodiment, the photoconductive layer is provided over the entire surface of the inner surface of the inner glass pane.

[0018] The arrangement of the light source outside the composite of the pane and the light-conducting layer makes it possible to omit the complex lamination of the lighting unit into the composite glass pane. In addition to this, the need for the conduction of the necessary electrical energy for the lighting unit into the composite glass pane is also omitted, since in the vehicle glazing according to the improved concept the light coupling is performed into the light-conducting layer either directly or via a corresponding light guide.

[0019] Also, due to the special configuration of the light source at the edge of the composite or the photoconductive layer, the light source made from LEDs is exposed to less thermal stress than, for example, when laminated in a glazing. Furthermore, the light source is in relatively poor contact with the intermediate layer, which results in a relatively poor chemical interaction between the light source and the intermediate layer (increased lifetime of the light source). In addition to this, the light source can be easily replaced so that destruction of the composite between the pane and the photoconductive layer does not occur.

[0020] The light source is preferably one or more modules including light emitting diodes (LEDs), each including a plurality of light emitting diodes and associated electronic components fixed to a printed circuit board, where the modules are positioned such that the emitting faces of the LEDs are directed towards the edge of the first sheet of glass.

[0021] The LED module is preferably selected so that it is most efficient in terms of the heat energy released per unit of length of the module when it is switched on, for example less than 1.5 W / decimeter, preferably less than 1 W / decimeter, more preferably less than 0.5 W / dm2 of heat energy released per unit of length of the module when it is switched on.

[0022] The thermal energy emitted by an LED module depends not only on its electrical consumption, expressed in watts, but also on its light output. In fact, at a given level of electrical consumption, the heat emitted increases as the light output decreases. However, this does not mean in any way that an attempt is made in the present invention to use LED modules with low light output that emit large amounts of heat. The reason that the present invention is further defined with the aid of this parameter is simply that below a certain level, the heat generated by the module does not result in an undesirable temperature increase and the technical problem of shortening the lifespan of the LEDs is present to a relatively small extent or in some cases does not exist at all.

[0023] However, those skilled in the art will appreciate that it is difficult to define an exact threshold value for this value, which depends on factors that may include the containment conditions of the LED module, the resistance of the LEDs to high temperatures, or the degree of shortening of the LED's lifespan that is deemed acceptable.

[0024] In another embodiment, the light source is a light transmitting optical fiber, a waveguide combined with an LED, or a laser diode.

[0025] According to another embodiment, the light source can be encapsulated on the edge of the glazing. The encapsulation means can be an element prepared by injection molding or a preformed bead, such as a bead of adhesive or elastomer, applied and fixed at the boundary of the glazing unit on the first main surface of the first sheet and, if necessary, also on the first main surface of the second sheet, if the shape of the boundary of the glazing unit is suitable for this.

[0026] The light source can be fixed on the edge of the glazing with the aid of a resin or optical adhesive. Thus, the light source and in particular the LEDs and their associated electronic components fixed on a printed circuit board are fixed on the glazing edge by a polymeric material such as silicone, epoxy, polyurethane, etc. Due to the optical resin, the beam shape from the light source can be adapted. Thus, the light source is protected from moisture while the correct transmission level is maintained to allow the correct light injection into the glass.

[0027] The present invention allows producing a significant reduction in light loss due to absorption, and another possible way to obtain a relatively large illumination power would be to use a relatively powerful light source.

[0028] In various embodiments, an optional retaining element can be provided on the glazing, allowing for fixing on the body of the vehicle. Additionally or alternatively, an optional foam embedment of the edge area of ​​the composite made of the pane and the light-conducting layer can be provided, which can also encapsulate the light source.

[0029] In some embodiments of the vehicle glazing, the light-conducting layer extends over the entire surface of the inner surface of the interior glass pane, such that the pane and the light-conducting layer each form a composite glass, and in minor variations thereof, the light-conducting layer can also extend over the entire surface of the pane, with the exception of the edge regions of the pane.

[0030] In an alternative embodiment, the light-conducting layer is applied in one or more partial regions of the surface of the pane. For example, the light-conducting layer has a strip or ring shape and preferably extends on one or more edges of the pane. Decoupling of light from the light-conducting layer is performed in this case, for example, not only in the direction perpendicular to both main surfaces of the pane or the light-conducting layer, but also at the edge not facing the light source or at the end side of the light-conducting layer not facing the light source. Thus, particularly desirable light moods can be achieved.

[0031] According to the invention, the light-conducting layer is made of a transparent plastic, in particular polyvinyl butyral, PVB. In particular, the decoupling means are formed, for example, by light-scattering particles applied on the surface of the light-conducting layer. The light-scattering particles are preferably not visible to the naked eye and create a transparent impression of the plastic layer when the light source is turned off. The embedded particles create a scattering of light in the particles such that the light is incident at a certain angle on the surface of the light-conducting layer, thus allowing it to exit. By having a PVB film with light-scattering particles provided on the surface of the plastic interlayer, the refractive index is the same as the PVB interlayer film used to laminate the glazing.

[0032] In other embodiments, in the photoconductive layer used, the decoupling means can be formed by structuring the surface of the photoconductive layer. The structuring is preferably carried out on the entire surface of the photoconductive layer. Alternatively, the desired light image can be generated only by regional structuring. Furthermore, preferably, the main surface of the photoconductive layer that faces the pane is structured. The structuring of the surface can be carried out, for example, by mechanical structuring, such as for example the indentation of a structure, by printing, in particular by using pad printing, by etching or by blasting methods, for example sandblasting.

[0033] The photoconductive layer is implemented as a flexible film and a thin plastic interlayer.

[0034] Such flexible films can be laminated onto panes with little manufacturing engineering expenditure and in the same manner as conventional thermoplastic interlayer lamination for bonding, for example, two panes of glass together.

[0035] In the above described embodiment, the glazing is a glazing roof.

[0036] The surfaces of the glass panes are typically designated as follows: The outer surface of the outer pane is designated Surface 1 (P1, surface 1). The inner surface of the outer pane is designated Surface 2 (P2, surface 2). The outer surface of the inner pane is designated Surface 3 (P3, surface 3). The inner surface of the inner pane is designated Surface 4 (P4, surface 4).

[0037] In the above embodiment, a low-E coating (low emissivity layer) as a reflective thermal radiation coating can be provided on the face surface (P4) of the glazing, more particularly on the glass roof directed towards the passenger compartment. Thus, a glazing roof provided with a thermal radiation reflective coating, more particularly a low-E coating, provides the best possible compromise between outward visibility through the roof and good thermal properties due to its long-wave infrared (IR) energy reflective properties.

[0038] Also, according to an embodiment of the present invention, the thermal radiation reflecting coating can be called a coating with low emissivity, an emissivity reducing coating, a low-E coating or a low-E layer. Its role is to reflect thermal radiation, specifically IR radiation with a longer wavelength than the IR component of solar radiation. At low exterior temperatures, the low-E coating reflects heat back to the interior and reduces the cooling of the interior. At high exterior temperatures, the low-E coating prevents the absorbed thermal radiation of the heated glazing from being re-emitted towards the interior and reduces the heating of the interior. On the interior side of the inner pane, the coating according to the invention reduces the emission of thermal radiation from the pane to the interior particularly effectively in summer and reduces the transmission of heat into the exterior environment in winter.

[0039] It has been chosen to place the coating at position 4, despite the fact that in this position the layer is not protected from degradation, in particular mechanical degradation. A low-E layer can be chosen which has sufficient mechanical and chemical resistance.

[0040] Advantageously, for good mechanical resistance, the coating is a "hard" layer such as one produced by PECVD, CVD or pyrolysis techniques, although low-E systems can also be produced using vacuum cathode sputtering techniques, provided that the resulting system is composed of layers with sufficient resistance.

[0041] According to the invention it is preferred to use low-emissivity coating systems whose emissivity is less than 0.3, preferably less than 0.2 and according to a particularly preferred manner less than 0.1.

[0042] The most common pyrolytic low-E (low emissivity) systems have a layer of doped tin oxide deposited on a first layer that has the role of neutral color in reflection. The layer in contact with the glass is usually a layer of silica or silicon oxycarbide, optionally modified by additives. In comparison with the layers of systems deposited by cathode sputtering, the tin oxide layers are relatively thick, i.e., more than 200 nm in thickness, in certain cases more than 450 nm. These thick layers have sufficient resistance to withstand exposure to mechanical and / or chemical attack.

[0043] According to one embodiment, a filtering infrared radiation coating can be provided on the inner surface (P2) of the outer glass pane. The coating can be provided on the inner surface (P3) of the inner glass pane. The coating comprises one or more metal layers, essentially based on silver, combined with a dielectric layer protecting the metal layer on the one hand. An infrared reflective coating can be present in the glazing, usually facing the intermediate PVB layer, such that the coating is positioned in P2 or P3. The infrared reflective coating preferably comprises n infrared reflective (IR) layers and n+1 dielectric layers, where n≧1, such that each IR layer is surrounded by two dielectric layers. The IR layer may be made of silver, gold, palladium, platinum, or alloys thereof, while the dielectric layer may typically comprise an oxide, nitride, oxynitride, or oxycarbide of Zn, Sn, Ti, Zr, Si, In, Al, Bi, Ta, Hf, Mg, Nb, Y, Ga, Sb, Mg, Cu, Ni, Cr, Fe, V, B, or mixtures thereof. The role of the IR reflective coating is to reflect the infrared portion of the solar radiation. Typical infrared reflective coatings can be applied by physical vapor deposition to form a coating having a thickness in the range of 10-250 nm.

[0044] According to one embodiment, solutions such as electrically powered functional films are provided between the outer glass pane and at least one thermoplastic interlayer, whose conditions of use have already been proposed, for the purpose of thermal protection, to modify the light transmission of the glazing, to adjust the tinting and privacy, to diffuse the reflection. Thus, the glazings can have functional films such as electrochromic means, whose variations are obtained by modifying the state of colored ions in the composition contained in these glazings. It is also a matter of glazings with layers of particles in suspension that are ordered or not ordered depending on the application of a voltage, such as systems called suspended particle devices (SPD) or, in a preferred embodiment, polymer dispersed liquid crystal (PDLC) films or guest host liquid crystals (GHLC), composed of polymers containing liquid crystals sensitive to the application of a voltage. These functional films allow the light level in the passenger compartment to be modified, their function being also to modify the level of anti-glare effect and privacy. Another role of these films is to protect the inside of the passenger compartment from heat. Specifically, these functional films are films that are switchable between a dark state and a semi-transparent or, in some cases, transparent state.

[0045] The glass panes used to form the laminated glazing unit may have the same composition and perhaps the same thickness, which may make it relatively easy for them to be pre-formed, for example, with the two sheets folded simultaneously. Most often, the glass sheets have different compositions and / or thicknesses, in which case they can be formed separately.

[0046] The possible presence of tinted interlayers participates in the absorption of light. Their use can be envisaged at least as a partial substitute for the contribution of the glass sheets to establishing a certain colour. This situation can arise, for example, when at least the outer glass sheets are sheets of poorly absorbing glass or even extra clear glass, in order to integrate a photovoltaic element in a glazing unit. However, the outer sheets may also be sheets of absorbing glass, and there is no need for a tinted interlayer. Thus, according to one embodiment of the present invention, an electrically powered light source or a functional film can be powered due to a photovoltaic cell. The energy generated by the photovoltaic cell can also be used to power some other elements of the vehicle.

[0047] The inner glass pane, which is directed towards the passenger compartment, can also be manufactured from clear glass, more preferably extra clear glass. This is most often absorptive, contributing to an overall reduction in energy transmission. When its transmission is limited, this allows non-transparent elements present in the glazing unit to be at least partially hidden from the view of the passengers. The inner glass pane can have a structuring of its outer surface (P3) of the inner glass pane. For example, the structuring is produced mechanically, for example by imprinting a structure into the surface. Alternatively, the structuring can also be realised by printing, in particular using pad printing, such that the printed material represents a scattering structure. A further possibility for the structuring of the surface of the layer consists of etching the surface, whereby the surface is roughened to produce a scattering effect. Furthermore, the roughening or structuring can also be realised by a blasting method, for example by sandblasting.

[0048] According to one embodiment of the present invention, the inner glass pane is provided with a notch. Thus, the lateral edge (i.e. the edge of the glass coming from the windshield to the backlight) is offset towards the center from the edge of the outer glass layer along at least a portion of its length to facilitate the attachment of the light source. More preferably, the offset is not provided along the entire periphery on the inner glass pane. In a preferred embodiment, the notch does not extend to the tip of the inner glass pane, so that the offset is not provided along the entire periphery of the inner glass pane. The notch and more specifically the edge of the notch are preferably more than 5 millimeters higher and more preferably more than 10 millimeters higher from the edge of the outer glass pane. Thus, for example, an array of LEDs can be attached to the outer glass layer in the exposed area where the two glass layer edges are usually offset from each other. The light is injected into the edge of the inner glass layer. The notch also allows for accurate positioning of the glass during assembly.

[0049] According to one embodiment of the invention, the inner glass pane is provided with a slot, preferably in the vicinity of a lateral edge of the inner glass pane, such that the light source is thus preferably provided within the slot.

[0050] According to another embodiment of the invention, the inner glass pane is provided with a notch having its edges polished with a polished surface finish to increase the transmission of visible light. The edges can also be polished to a convex, concave, or other shape to aid in focusing the light toward the center of the edge. In a preferred embodiment, at least the edges of the notch are polished to a flat profile (simple chamfer) and polished to promote the penetration of light from the light source into the inner glass pane. As a result, the edges have a relatively large optical transparency to the light from the light source.

[0051] According to one embodiment, the lighting glazing is a roof glazing for a vehicle. The roof glazing may be directly bonded to a vehicle or assembly, which is then mounted on the vehicle. Regardless of whether it is directly bonded to a vehicle or assembly, it is encapsulated in a molding.

[0052] Color in transmission and reflection is also important in the selection of glass sheets and interlayers.

[0053] The various described vehicle glazing embodiments allow for modular applicability. In particular, the light-conducting layer can be combined with existing pane or roof glazing without major design changes being required. The light-conducting layer can be constructed to have no or only a minor effect on the force-transmitting elements of the vehicle glazing.

[0054] According to the present invention, the photoconductive layer has light scattering particles applied to at least one surface of the polymer interlayer film, where the polymer interlayer film comprises polyvinyl butyral. Preferably, the plasticizer content in the polymer interlayer film before lamination is 5% or less.

[0055] One advantage of using polyvinyl butyral (PVB) polymer interlayer films with very little or no plasticizer is the possibility of producing films with a particularly smooth surface and therefore a relatively good and uniform print image on the smooth side. The polyvinyl butyral material used for the film is also naturally highly compatible with standard PVB interlayers used in the glass industry. Moreover, PVB films that are plasticizer-free and therefore rigid can be printed by using new relatively economical roll-to-roll processes such as flexographic printing. This is not possible in the case of glass or soft PVB films.

[0056] Also preferably, the polymer interlayer film comprises a homo- or copolymer of (meth)acrylate, poly(vinyl)acetal, ionomer such as ethylene methacrylic acid copolymer, nitrocellulose, polystyrene, thermoplastic polyurethane, polycarbonate, polyvinyl chloride, polyolefin such as polyethylene or polypropylene, polyethylene terephthalate, ethylene-vinyl acetate, or mixtures thereof.

[0057] The light scattering particles are usually applied to at least one surface of the polymer interlayer film using a coating or printing process. In the case of printing, they can be applied via techniques commonly known in the printing industry, such as offset printing, gravure printing, flexographic printing, screen printing, and inkjet printing.

[0058] The thickness (T2) of the functional layer before lamination is preferably 0.1 μm to 100 μm, and more preferably 1.0 μm to 30 μm.

[0059] The functional layer preferably comprises light scattering particles and at least one matrix material. Suitable matrix materials include polymers in which the light scattering particles can be uniformly dispersed without decomposition. Preferably, the matrix material comprises homo- or copolymers of (meth)acrylate, methyl methacrylate, poly(vinyl)acetal, nitrocellulose, polystyrene, polyvinyl alcohol, polyurethane, polycarbonate, and polyvinyl chloride. Most preferably, the matrix material is polyvinyl butyral.

[0060] Additional components could be present in the functional layer. Examples of additional components include co-resins, solvents, UV absorbers, UV stabilizers, crosslinkers, curing agents, accelerators, photoinitiators, surfactants, stabilizers, fillers, thixotropy modifiers, and plasticizers.

[0061] Any light scattering material known in the art may be utilized. Preferably, the light scattering particles are TiCh, TiO 2 , ZnO, Al 2 O 3 , ZrCh, ZrO 2 , PbSCh, PbSO 4 , BaSCh, BaSO 4 , CaCO 3 , glass, polymer, and mixtures thereof. The light scattering particles may be used as solid or hollow beads or fibers.

[0062] Preferably, the light scattering particles are present in the functional layer in an amount of 0.1 to 10% by weight, more preferably 0.5 to 5% by weight, and most preferably 1 to 2.5% by weight.

[0063] Suitable photoconductive layers according to the present invention are described in patent application WO2021005162.

[0064] Preferably, the functional layer completely covers at least one surface of the polymeric interlayer film.

[0065] Also preferably, the functional layer covers only a portion of the polymer interlayer film. Thus, the functional film can be applied in the form of a pattern and can realize illumination in the form of a specific pattern, which is not possible in the case where the light scattering particles are evenly distributed in the laminate. Thus, preferably, the functional film covers no more than 90%, no more than 80%, no more than 75%, and most preferably less than 50% of at least one surface of the polymer interlayer film. This embodiment is particularly useful in the case of informational and / or decorative glazing for aircraft, trains, or ships, and in the case of use in architectural areas, especially in the case of ship windows, elevators, or facade glazing.

[0066] The thickness of the functional layer is preferably 0.1-50 μm, more preferably 1-30 μm, most preferably 2-20 μm, as measured by IR microscopy. Depending on where the finished glazing is used, for example in the case of an automobile sunroof, the outer glass pane facing the sun can often be tinted to reduce the solar energy transmitted through the laminate into the vehicle. Thus, an electrically powered functional film such as PDLC, SPD, or other known switchable films mentioned above may be used between the outer glass pane and the photoconductive layer, in which case light would be absorbed and lost for illumination purposes. Typically, the switchable film is laminated between at least two plastic interlayers, such as PVB, EVA, etc., and is provided between the outer glass pane and the photoconductive layer. The switchable film may be surrounded by a thermoplastic interlayer, as well as a frame, and the assembly is then laminated between at least two plastic interlayers.

[0067] To form the functional layer, a printing ink was selected consisting of 0.40 wt.-% titanium dioxide (as light scattering particles) having a particle size D50 of 0.15 μm determined by laser diffraction according to DIN 13320, 27.0 wt.-% poly(methyl methacrylate) (PMMA) (as matrix material), and 36.3 wt.-% 2-butoxyethanol acetate, as well as 36.3 wt.-% cyclohexanone (as sacrificial solvent).

[0068] The invention will now be described in more detail with reference to several exemplary embodiments based on the figures. Elements with equivalent functions or actions bear in this case the same reference signs. Insofar as an individual element is described with respect to one of the figures, its description in the following figures is not necessarily repeated.

[0069] The drawings are as follows: [Brief description of the drawings]

[0070] [Figure 1] 1 shows a plan view of a vehicle roof having a transparent roof portion.

[0071] [Diagram 2] 1 illustrates one embodiment of a configuration according to the present invention.

[0072] [Diagram 3] 1 illustrates one embodiment of a configuration according to the present invention.

[0073] [Figure 4] 1 shows a further embodiment of a configuration according to the present invention.

[0074] [Diagram 5] 1 shows a further embodiment of a configuration according to the present invention.

[0075] [Figure 6] 1 shows a further embodiment of a configuration according to the present invention.

[0076] [Figure 7] 1 shows a further embodiment of a configuration according to the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0077] 1 shows a passenger car 1, in which the vehicle roof 2 has a roof portion in the form of a glazing roof 3 arranged in a roof opening 4. The covering 3 is implemented, for example, as a laminated vehicle glazing. The glazing unit according to the invention is preferably mounted on the vehicle such that the inner glass pane is in contact with the passenger compartment of the vehicle and the outer glass pane is arranged relatively close to the exterior of the vehicle, typically in direct contact with the atmosphere outside the vehicle.

[0078] FIG. 2 shows an embodiment of a vehicle glazing 3 having an exterior glass pane 10 and an interior glass pane 11. The exterior glass pane may be tinted glass. A light-conductive layer 12 is provided on the interior surface (P3, also called face 3) of the interior glass pane 11. The light-conductive layer 12 comprises light-scattering particles applied to at least one surface of the polymer interlayer film 12. In one embodiment, the scattering particles 121 are provided on the PVB 120 by ink printing. The light-conductive layer 12 is bonded to the interior glass pane 11 on its interior surface P3 by lamination. The light-conductive layer 12 extends over the entire surface of the interior surface (P3) of the interior glass pane 1. In addition, in the vehicle glazing of FIG. 2, a light source 16 is provided, which is configured to couple light into the edge side 122 of the light-conductive layer 12 and / or into the edge side 110 of the interior glass 11.

[0079] An opaque band 25 along the periphery of the glazing is provided to protect and hide non-aesthetic elements such as adhesives, fastening means, etc. fixed on the glazing. Black bands are well known to those skilled in the art. A black band, typically enamel, may be provided around the inner surface P2 of the outer glass pane 10 and the outer surface P4 of the inner glass pane 11. The black band may be provided only within the inner surface P2.

[0080] Inner glass pane 10 may be clear glass and inner glass pane 11 may be extra clear glass.

[0081] The light source 16 is provided in such a way that light is emitted perpendicularly to the edge 110 of the inner glass pane 11. The light-conducting layer 12 is in this case specifically configured to conduct the light coupled in longitudinally through the layer to the end side. Furthermore, the light-conducting layer 12 has a surface structuring 13, which serves as a decoupling means for the light, such that light exit of the light coupled in laterally is effected via a preferably relatively lower main surface. The structuring 13 is in this case specifically provided on the side of the layer 12 facing towards the inner glass pane 11.

[0082] Decoupling is based on the effect that light is refracted or scattered on the structure 13, causing it to be emitted at an angle that allows it to exit the surface of layer 12. Without structuring, the coupled-in light is normally incident on the surface of layer 12 at a flat angle such that total internal reflection of the light occurs.

[0083] For example, the structuring 13 of the surface of the layer 12 is produced mechanically, for example by imprinting a structure into the surface. Alternatively, the structuring can also be produced by printing, in particular by using pad printing, so that the printed material exhibits scattering structures. A further possibility for the structuring of the surface of the layer 12 consists of etching the surface, whereby the surface is roughened to produce a scattering effect. Furthermore, the roughening or structuring can also be achieved by blasting methods, for example by sandblasting.

[0084] Light source 16 is preferably one or more modules including light emitting diodes (LEDs), each including a plurality of light emitting diodes and associated electronic components fixed to a printed circuit board, with the modules positioned such that the emitting faces of the LEDs are directed toward the edge of the first sheet of glass.

[0085] The light source 16 can be enclosed in a housing so as to fix it on the glazing and protect it from external influences. The light source 16 can be encapsulated on the edge of the glazing. The encapsulation means can be an element prepared by injection molding or a preformed bead, such as a bead of adhesive or elastomer, applied and fixed at the boundary of the glazing unit on the first main surface of the first sheet and, if necessary, also on the second main surface of the second sheet, if the shape of the boundary of the glazing unit is suitable for this.

[0086] The LEDs may be side-emitting or top-emitting LEDs. Side-emitting LEDs form a preferred embodiment. With side LEDs, the LEDs can be easily positioned relative to the plane of the inner glass pane 11 perpendicular to the plane of the inner glass pane 11 for better coupling inside the inner glass pane 11.

[0087] In another embodiment, the light source 16 may be an LED or a diode laser or a waveguide coupled with an optical fiber.

[0088] In a particular embodiment shown in Fig. 3, the light source 16, in an embodiment an LED module, is arranged in a cutout 32a, 32b provided along at least a portion of the lateral edge 31c, 31d of the inner glazing. The LED module is then fixed on the outer glass pane 10, for example by means of an encapsulation means. The cutout is spaced from the edge of the lateral edge of the inner glass pane 11 by a distance at least equal to the width of the light source 16, more particularly the LED module. The light source is preferably encapsulated in an encapsulation means that contacts a partial area of ​​the inner surface (P2) of the outer glass pane 10. The cutout may be spaced from the edge by a distance less than 20 mm.

[0089] A thermoplastic interlayer 14 is provided between the inner surface (P2) of the outer glass pane 10 and the light-conductive layer 12. The interlayer 14 can have several functions. On the one hand, it can be used as a lamination layer, providing a permanent bond between the pane 10 and the layer 12. In addition to this, the interlayer 14 can be implemented as a refractive layer, in particular having a lower refractive index than the light-conductive layer. Thus, light incident on the interface between the layers 12 and 14 remains in the light-conductive layer 12 and does not pass into the inner pane 11 (and also into the outer pane 10). As a result, light absorption in the pane 11 or light emission from the vehicle to the surroundings is avoided. The interlayer 14 is, in a preferred embodiment, a grey or tinted PVB. The thickness of the PVB can be standard, about 0.75 mm to 0.8 mm. However, the thickness can also be less than 0.75 mm. In another embodiment, several relatively thin interlayers 14 can be superimposed. The use of grey PVB has the advantage that it absorbs the light of the structuring 13 in order to concentrate the light on the inside of the glazing and / or to ultimately reduce the double image created by the structuring 13 on the outer glass pane. This is particularly useful when the glazing is provided with an IR-reflective coating, for example.

[0090] In addition, the intermediate layer 14 may also function as a splinter protective layer or film. For example, the layer 14 is implemented for this purpose from polyvinyl butyral (PVB). In some embodiments, the intermediate layer has a thickness of T1.

[0091] The interlayer 14 is preferably provided to function not only as a lamination layer, but also as a refractive layer and at the same time as a splinter protective film. Alternatively, the three functions can be provided by a corresponding layer structure of several films. The interlayer extends over the surface of the glass pane 10. The laminated glazing thus includes at least one light source that is provided with surface lighting having improved uniformity. Another object of at least some embodiments is to provide such a surface lighting panel that provides relatively uniform diffused surface lighting.

[0092] Figure 4 shows a further embodiment of a vehicle glazing 3 based on the embodiment shown in figure 2. In this embodiment, an infrared (IR) reflective coating 15 can be provided at least on the surface of the inner surface (P2) of the outer glass pane 10 facing the first thermoplastic interlayer 14. The infrared reflective coating preferably comprises n infrared reflective (IR) layers and n+1 dielectric layers, where n>1, such that each IR layer is surrounded by two dielectric layers. The IR layers can be made of silver, gold, palladium, platinum or alloys thereof, while the dielectric layers can typically comprise oxides, nitrides, oxynitrides or oxycarbides of Zn, Sn, Ti, Zr, Si, In, Al, Bi, Ta, Hf, Mg, Nb, Y, Ga, Sb, Mg, Cu, Ni, Cr, Fe, V, B or mixtures thereof. The role of the IR reflective coating is to reflect the infrared part of the solar radiation. A typical infrared reflective coating can be applied by physical vapor deposition to form a coating having a thickness in the range of 10-250 nm. The role of the IR reflective coating is to confine heat within the interior of the vehicle compartment.

[0093] Furthermore, a low-emissivity coating 17 as a reflective thermal radiation coating can also be provided on the surface of the glazing face (P4), more particularly on the glass roof facing towards the passenger compartment. Thus, a glazing roof provided with a thermal radiation reflective coating, more particularly a low-E coating, provides the best possible compromise between outside visibility through the roof and good thermal properties due to its long-wave infrared (IR) energy reflective properties.

[0094] Figure 5 shows, in another embodiment, the glazing 3 described in figure 2 further comprising a film with photovoltaic cells 18. The film with photovoltaic cells 18 is bonded to the outer glass pane 10 by a thermoplastic interlayer 14b. In particular, the film with photovoltaic cells 18 is sandwiched between at least two thermoplastic interlayers 14b, 14c. The thermoplastic interlayers are preferably made of PVB or EVA or PET. The photovoltaic cells are, for example, crystalline silicon (C-Si) solar cells, perovskite, tandem cell type thin-film solar cell films, or a combination of these solar cells.

[0095] The solar cells may be partially transparent, or transparent areas may be formed by rows of solar cells, in which case natural light may pass through each row between each row. In this case, it is preferable to use a colored thermoplastic intermediate layer 14b, c or a functional film such as PDLC, SPD, etc. between the photovoltaic cell film and the photoconductive film 12 to avoid the interference of the natural light with the photoconductive film 12.

[0096] The solar cell design may be completely opaque to natural light and therefore there is no need to have a functional film such as PDLC, SPD, etc. between the photovoltaic cell film and the photoconductive film 12, in other words the entire glazing is covered by the opaque solar cell.

[0097] Thus, external light is being captured by the solar cells through the exterior glass pane 10. The electricity generated by the photovoltaic cells can be used for the light source 16 or for any element of the glazing or vehicle that needs to be electrically powered.

[0098] As shown in FIG. 4, the outer glass pane 10 may be larger than the inner glass pane 11 .

[0099] FIG. 6 shows, in another embodiment, the glazing 3 described in FIG. 2 further comprising an electrically powered functional film 19 selected from the group of PDLC films, LCD films, GHLC films, SPD films, electrochromic films. The electrically powered functional film 19 can be provided between the outer glass pane 10 and the thermoplastic interlayer 14. The electrically powered functional film is bonded to the outer and inner glass panes by transparent polymeric materials commonly used for this purpose, such as, for example, poly(vinyl butyral) (PVB), thermoplastic polyurethane (TPU), or ethylene vinyl acetate copolymer (EVA). The interlayer may be free of plasticizers. The use of an IR-reflective coating in the inner surface (P2) or P3 of the outer glass pane to reduce the heat generated by solar radiation can not only improve the performance of the switchable film embedded in the glazing 3, but also improve the comfort for occupants in the vehicle cabin with the laminated glazing roof. The thermal coating 15 within the glazing 3 is positioned directly beneath the top, upper or outermost exterior glass pane 10 to provide efficient heat reduction and thereby provide thermal protection to both the other optical components within the glazing 3 as well as, for example, occupants within the vehicle cabin in which the glazing 3 is used.

[0100] In another embodiment, the assembly with photovoltaic cells can be provided on at least a portion of the surface of the inner surface (P2) of the outer glass pane (10). The assembly with photovoltaic cells can be used to electrically power the light source 16 and / or functional films such as those selected from PDLC films, LCD films, GHLC films, SPD films, electrochromic films as mentioned above, or partially to electrically power some other elements of the vehicle such as the engine, the air conditioning system, etc. The assembly with photovoltaic cells can be laminated to the outer glass pane 10 by a transparent polymeric material such as poly(vinyl butyral) (PVB).

[0101] The present invention therefore proposes a glazing, more particularly a glazing roof for a vehicle, that combines lighting, a photovoltaic cell film, and / or a functional film such as a switchable film (PDLC, LCD, SPD, electrochromic, etc.) that is switchable between a dark state and a translucent or possibly transparent state while controlling the thermal properties of the glazing through an IR reflective coating and / or a low emissivity coating.

[0102] In a preferred embodiment, the inner glass pane 11 is extra clear glass, which has a low absorption coefficient, allowing for the most efficient coupling of light.

[0103] The outer glass pane 10 may be a clear glass pane.

[0104] The thickness of the outer and inner glass panes 10, 11 may be the same or different. The thickness is preferably less than 3 mm, most preferably less than 2.5 mm. The outer glass pane 10, and more preferably the inner glass pane 11, are thin glass sheets, i.e. having a thickness of less than 2.1 mm.

[0105] The outer and inner glass panes 10, 11 may be symmetrical (same length) or asymmetrical, with the inner glass pane 11 being smaller than the outer glass pane 10. In this embodiment, the light source 16 may be located in the area not covered by the outer glass pane and facing the edge 110 of the inner glass. The outer glass pane 10 is used as a support for at least one light source 16.

[0106] In one embodiment, the light source 16 is provided in a cutout formed in the inner glass pane 11. In a preferred embodiment, the cutout is provided only in the area in which the light source 16 is located. The light source 16 is, in a preferred embodiment, an LED.

[0107] FIG. 7 shows a further embodiment of a vehicle glazing 3, in which a number of light sources 16 are provided along the lateral edges 31a, 31b of the glazing. Thus, uniform lighting can be obtained. Each of the light sources 16 can be managed separately, for example according to the zones A and B to be illuminated. It should be understood that more than two zones can be illuminated. Thus, segmentation can be provided. Each zone can further comprise a switchable film 19. Light sources 16, more particularly LED modules, each including a number of light-emitting diodes and associated electronic components fixed to a printed circuit board, are provided, in which the modules are positioned such that the emission surface of the LEDs faces towards the edge of the inner glass pane and emits perpendicularly towards the plane of the inner glass pane. The LED modules can be spaced apart from each other by a predefined distance so as to have uniform lighting in the glazing 3.

[0108] The LED module is, in one embodiment, arranged in a cutout provided along at least a portion of the lateral edge 31c, 31d of the inner glazing. The LED module is then fixed on the outer glass pane 10. The cutout is spaced from the edge of the lateral edge of the inner glass pane 11 by a distance at least equal to the width of the light source 16, more particularly the LED module. The light source is preferably encapsulated in an encapsulation means that contacts a partial area of ​​the inner surface (P2) of the inner glass pane.

[0109] Variations and combinations of the described embodiments are of course possible and are covered by the invention.

[0110] Also, for the avoidance of doubt, the present invention is applicable for all means of transport such as cars, vans, lorries, motorcycles, buses, trams, trains, aircraft, helicopters and the like. According to one embodiment of the present invention, the glazing may be part of a glazing roof, sidelight, backlight or windscreen of a motor vehicle.

Claims

1. an external glass pane (10) having an outer surface (P1) and an inner surface (P2) and edges; - an internal glass pane (11) having an outer surface (P3) and an inner surface (P4) and an edge (110); A lighting vehicle glazing (3) having - said outer glass pane (10) and said inner glass pane (11) are laminated together via at least a first plastic interlayer (14) having a thickness T1, The lighting vehicle glazing (3) comprises: a light-conducting plastic interlayer (12) in contact with said outer surface (P3) of said inner glass pane (11) and having a thickness T2 less than T1, said light-conducting plastic interlayer (12) being adapted to conduct light coupled into one of its end sides substantially joined to said inner glass pane (11); at least one light source (16) configured to couple light into at least one edge side 122 of said light-conducting layer and / or into an edge side 110 of said inner glass 11; and 1. A vehicle glazing (3), wherein the light-conducting plastic interlayer (12) comprises a thermoplastic interlayer (120) provided with a functional layer (121) having light-scattering particles applied to at least one surface of the thermoplastic interlayer (120) that is in contact with the outer surface (P3) of the inner glass pane (11), and wherein the light-conducting plastic interlayer (12) comprises decoupling means (13) through which light emission of transmitted light from the light source (16) is brought about on at least one of the upper main surfaces of the light-conducting layer.

2. 2. Vehicle glazing (3) according to claim 1, wherein the light-conducting plastic interlayer has a pattern (13) on at least a portion of one of its surfaces.

3. 2. The vehicle glazing (3) of claim 1, wherein the light source (16) is one or more modules containing light emitting diodes (LEDs), each module including a plurality of light emitting diodes and associated electronic components secured to a printed circuit board.

4. 2. The vehicle glazing (3) of claim 1, wherein the light source (16) is one or more modules containing light emitting diodes (LEDs), each module including a plurality of light emitting diodes and associated electronic components fixed to a printed circuit board, the modules positioned such that an emitting face of the LEDs is directed toward the edge of the interior glass pane and emits perpendicular to the plane of the interior glass pane.

5. 2. The vehicle glazing (3) according to claim 1, wherein the light source (16) is arranged in a notch (32a, 32b) provided in the inner glass pane (11) from its lateral edges (31c, 31d) and is fixed on the inner surface (P2) of the glass pane (10).

6. 2. The vehicle glazing (3) of claim 1, wherein an electrically powered functional film (19) selected from the group consisting of PDLC, GHLC, LCD, SPD, and electrochromic films is provided between the exterior glass pane and the first plastic interlayer.

7. 2. The vehicle glazing (3) of claim 1, wherein a photovoltaic cell film (18) is provided between the exterior glass pane and the first plastic interlayer.

8. 2. The vehicle glazing (3) according to claim 1, wherein the light source (16) is a side LED.

9. 2. The vehicle glazing (3) of claim 1, wherein the light source (16) is encapsulated in an encapsulation means that contacts a partial area of ​​the inner surface of the inner glass pane.

10. 2. Vehicle glazing (3) according to claim 1, wherein the light-conducting plastic interlayer (12) extends over the entire surface of the pane.

11. 2. The vehicle glazing (3) of claim 1, wherein the light-conducting plastic interlayer (12) is made from PVB.

12. 2. The vehicle glazing of claim 1, wherein the light-conducting plastic interlayer (12) has light-scattering particles (121) provided by printed ink.

13. 2. The vehicle glazing (3) according to claim 1, wherein the light-conducting plastic intermediate layer (12) has a structuring of its surface facing the outer surface (P3) of the inner glass pane (11) formed by at least one of mechanical structuring, printing, etching and blasting.

14. 2. Vehicle glazing (3) according to claim 1, wherein the thickness T2 of the light-conducting plastic interlayer is less than 0.050 mm, more preferably less than 0.03 mm.

15. 2. The vehicle glazing (3) according to claim 1, wherein a solar control coating (15) is provided on at least the inner surface (P2) of the outer glass pane (10) or the outer surface (P3) of the inner glass pane (11).

16. 2. The vehicle glazing (3) according to claim 1, wherein a low-e coating (17) is provided on at least a portion of the inner surface (P4) of the inner glass pane (11).

17. The vehicle glazing of claim 1 , wherein the glazing is a glazing roof.

Images