LAMINATED PANE, HEATABLE IN REGIONS, FOR PROJECTION ARRANGEMENT

Abstract

A laminated pane includes an outer and inner panes and a thermoplastic intermediate layer arranged between the outer and inner panes, wherein the outer and inner panes each have an outer and an inner side, and the inner side of the outer pane and the outer side of the inner pane face one another, and the thermoplastic intermediate layer contains at least one masking layer, and the masking layer is opaque at least in one region, a heating element which is arranged within the opaque region of the masking layer, and a reflective layer adapted to reflect visible light, wherein the reflective layer is arranged spatially in front of the at least one masking layer in the viewing direction from the inner pane to the outer pane and overlaps at least partially with the opaque region of the masking layer.

Claims

1. A laminated pane, comprising: an outer pane, an inner pane, and a thermoplastic intermediate layer arranged between the outer pane and the inner pane, wherein the outer pane and the inner pane each have an outer side and an inner side, and the inner side of the outer pane and the outer side of the inner pane face one another, and the thermoplastic intermediate layer contains or consists of at least one masking layer, and the at least one masking layer is opaque at least in one region, a heating element which is arranged within the opaque region of the at least one masking layer, and a reflective layer adapted to reflect visible light, wherein the reflective layer is arranged spatially in front of the at least one masking layer in the viewing direction from the inner pane to the outer pane and overlaps at least partially with the opaque region of the at least one masking layer.

2. The laminated pane according to claim 1, wherein the at least one masking layer further comprises a transparent region.

3. The laminated pane according to claim 1, wherein the thermoplastic intermediate layer contains the at least one masking layer and a transparent layer, and the at least one masking layer is completely opaque.

4. The laminated pane according to claim 1, wherein the at least one masking layer is arranged to be at least adjacent to a lower edge of the laminated pane.

5. The laminated pane according to claim 1, wherein the opaque region of the at least one masking layer is arranged in a frame-like, circumferential manner in an edge region of the laminated pane and, in a section which is in overlap with the reflective layer, has a greater width than in sections different therefrom.

6. The laminated pane according to claim 1, wherein the reflective layer and the opaque region each have a surface, which are arranged congruently, or the opaque region has a larger surface than the reflective layer, and the reflective layer overlaps completely with the opaque region.

7. The laminated pane according to claim 1, further comprising a first masking strip which is applied in regions on the inner side of the outer pane, and wherein at least the heating element overlaps completely with the first masking strip.

8. The laminated pane according to claim 1, wherein the reflective layer has an average transmission in the visible spectral range of at least 60%, and/or the reflective layer reflects at least 15% of the light incident on the reflective layer.

9. The laminated pane according to claim 1, further comprising a first busbar and a second busbar, which are provided for connection to a voltage source, wherein the first and the second busbars are connected to an edge region of the heating element in such a way that a current path through the heating element for a heating current is formed between the first and second busbars.

10. The laminated pane according to claim 1, wherein the heating element is completely embedded in the opaque region of the at least one masking layer.

11. The laminated pane according to claim 1, wherein the heating element is designed in the form of heating wires which have a diameter of 10 ?m to 300 ?m.

12. The laminated pane according to claim 11, wherein the heating wires contain or consist of a metal.

13. The laminated pane according to claim 1, wherein a highly-refractive coating with a refractive index of at least 1.7 is arranged at least in one region of the inner side of the inner pane, which region is in overlap with the reflective layer, and wherein the highly-refractive coating is always arranged spatially in front of the reflective layer when looking onto the inner side of the inner pane.

14. A projection arrangement comprising: a laminated pane according to claim 1, a display device assigned to the reflective layer and having an image display directed onto the reflective layer, the image of which image display is reflectable by the reflective layer, wherein at least the region of the reflective layer which is in overlap with the opaque region of the at least one masking layer can be irradiated by the display device.

15. A method for producing a laminated pane according to claim 1, the method comprising: (a) arranging the outer pane, the thermoplastic intermediate layer, the heating element, the reflective layer, and the inner pane to form a layer stack, wherein the thermoplastic intermediate layer is arranged between the outer pane and the inner pane, and the heating element is arranged within the opaque region of the at least one masking layer, and wherein the reflective layer is arranged spatially in front of the at least one masking layer in the viewing direction from the inner pane to the outer pane and overlaps at least partially with the opaque region of the at least one masking layer, and (b) laminating the layer stack obtained to form a laminated pane.

16. A method comprising providing a laminated pane according to claim 1 in a vehicle for traffic on land, in the air, or on water.

17. The laminated pane according to claim 1, wherein the laminated pane is a laminated pane of a projection arrangement.

18. The laminated pane according to claim 2, wherein the opaque region extends over less than 30% of a total surface of the laminated pane.

19. The laminated pane according to claim 3, wherein the at least one masking layer extends over less than 30% of a total surface of the laminated pane.

20. The laminated pane according to claim 4, wherein the at least one masking layer extends over at least 5% of a total surface of the laminated pane.

Description

[0103] The invention is explained in more detail below with reference to exemplary embodiments, wherein reference is made to the accompanying figures. In a simplified, not-to-scale representation:

[0104] FIG. 1 shows a plan view of an embodiment of the laminated pane according to the invention;

[0105] FIG. 1a shows a cross-sectional view of a projection arrangement according to the invention with the laminated pane of FIG. 1;

[0106] FIG. 2 shows a further cross-sectional view of a projection arrangement according to the invention with a further embodiment of the laminated pane according to the invention; and

[0107] FIGS. 3-6 show enlarged cross-sectional views of various embodiments of the projection arrangement according to the invention.

[0108] FIG. 1 shows a plan view of an embodiment of the laminated pane 1 according to the invention in a vehicle in a highly simplified, schematic representation. FIG. 1a shows a cross-sectional view of the exemplary embodiment from FIG. 1 in projection arrangement 100. The cross-sectional view of FIG. 1a corresponds to intersection line A-A of the laminated pane 1, as indicated in FIG. 1.

[0109] The laminated pane 1 comprises an outer pane 2 and an inner pane 3 with a thermoplastic intermediate layer 4, which is arranged between the outer and inner panes 2, 3. The laminated pane 1 is installed in a vehicle and separates a vehicle interior 14 from an external environment 15. The laminated pane 1 is, for example, the windshield of a motor vehicle.

[0110] The outer pane 2 and the inner pane 3 each consist of glasspreferably thermally pre-stressed soda-lime glassand are transparent to visible light. The thermoplastic intermediate layer 4 contains a masking layer 5 and a transparent layer 16.

[0111] The outer side I of the outer pane 2 faces away from the thermoplastic intermediate layer 4 and is, at the same time, the outer surface of the laminated pane 1. The inner side II of the outer pane 2 and the outer side III of the inner pane 3 each face the intermediate layer 4. The inner side IV of the inner pane 3 faces away from the thermoplastic intermediate layer 4 and is, at the same time, the inner side of the laminated pane 1. It is understood that the laminated pane 1 can have any suitable geometric shape and/or curvature. As a laminated pane 1, it typically has a convex curvature. The laminated pane 1 moreover has an upper edge located at the top in the installed position and a lower edge located at the bottom in the installed position, as well as a side edge located on the left and right.

[0112] A frame-like, circumferential first masking strip 7 is applied on the inner side II of the outer pane 2 in an edge region 13 of the laminated pane 1. The first masking strip 7 is opaque and obstructs the view of structures arranged on the inside of the laminated pane 1for example, an adhesive bead for gluing the laminated pane 1 into a vehicle body. The first masking strip 7 is preferably black. The first masking strip 7 consists of a non-electrically-conductive material traditionally used for masking stripsfor example, a black-colored screen-printing ink which is burnt in. The first masking strip 7 is arranged such that the masking layer 5 completely overlaps with the first masking strip. This means that, when looking through the laminated pane 1 from the external environment 15, it covers the masking layer 5 and all further structures located behind it.

[0113] Furthermore, as shown in FIG. 1A, the laminated pane 1 has a second masking strip 8 in the edge region 13 on the inner side IV of the inner pane 3. The second masking strip 8 is formed in a frame-like, circumferential manner. Like the first masking strip 7, the second masking strip 8 consists of a non-electrically-conductive material traditionally used for masking stripsfor example, a black-colored screen-printing ink which is burnt in.

[0114] The transparent layer 16 consists of a thermoplastic plastic composite filmpreferably polyvinyl butyral (PVB), ethylene vinyl acetate (EVA), and/or thermoplastic polyurethane (TPU). The transparent layer 16 extends from the upper edge region 13, 13 (beginning with the upper edge) flat along the upper edge and the side edges over the largest region (for example, 85% of the surface) of the inner side II of the outer pane 2 and the outer side III of the inner pane 3. The see-through region of the laminated pane 1 is in overlap with the transparent layer 16. The transparent layer 16 borders a masking layer 5 in the lower region. The masking layer 5 consists of an opaque, thermoplastic, plastic-composite filmpreferably polyvinyl butyral (PVB), ethylene vinyl acetate (EVA), and/or thermoplastic polyurethane (TPU). The masking layer 5 is colored black, for example. The masking layer 5 extends flat along the lower edge (in edge region 13, 13) of the laminated pane 1 and along the side edges until it adjoins the transparent layer 16. The transparent layer 16 and the masking layer 5 may overlap slightly (for example, 5 mm) along the region where they adjoin.

[0115] A reflective layer 11, which is vapor-deposited by means of the PVD method, is arranged in regions on the outer side III of the inner pane 3. When looking through the laminated pane 1 from the external environment 15, the reflective layer 11 is completely overlapped by the masking layer 5. The reflective layer 11 is thus not visible from the external environment 15. In FIG. 1, the region in which the reflective layer 11 is arranged is indicated by dashed lines. The reflective layer 11 is arranged such that it is not covered by the second masking strip 8 when looking through the laminated pane 1 from the vehicle interior 14. In the example shown, the reflective layer 11 is arranged in a strip-like manner along the lower edge such that it completely overlaps with the masking layer 5 but is not covered by the second masking strip 8. The reflective layer 11 is, for example, a metal coating which contains at least one thin-film stack with at least one silver layer and a dielectric layer. Alternatively, the reflective layer 11 can also be designed as a reflective film and be arranged on the outer side III of the inner pane 3. The reflective film can contain a metal coating or can consist of dielectric polymer layers in a layer sequence.

[0116] The laminated pane 1 moreover comprises a heating element 6 arranged within the masking layer 5. The heating element 2 has been arranged, for example, during the production process between the outer pane 2 and the masking layer 5. The heating element 6 has been enclosed by the masking layer 5 through pressure and heating during lamination, so that the heating element 6 in the exemplary embodiment shown is arranged closer to the inner surface II of the outer pane 2 than to the outer surface III of the inner pane 3. The heating element 6 is designed in the form of heating wires, for example. The heating wires are formed, for example, on the basis of copper. The diameter of the heating wires 6 is, for example, approximately 100 ?m. When looking through the laminated pane 1 from the vehicle interior 14, the heating element 6 is arranged behind the reflective layer 11 and is largely covered by the latter. The heating element 6 extends approximately orthogonally to the side edges and along the lower edge. The heating element 6 is not visible from the external environment 15 or from the vehicle interior 14, since it is completely covered by the first masking strip 7 and by the masking layer 5.

[0117] The heating element 6 is materially and electrically connected to a first busbar in a left edge region of the heating element and to a further, second busbar in a right edge region of the heating element (not visible in FIG. 1 and FIG. 1a) for making electrical contact. The busbars contain silver particles, for example, and have been applied by screen printing and subsequently burnt in. The length of the busbars corresponds approximately to the extension of the heating element 6 along the side edges of the laminated pane 1. If an electrical voltage is applied to the busbars, a uniform current flows through the heating element 6 between the busbars. The busbars are connected by means of supply lines to a voltage source which provides an on-board voltage customary for motor vehiclespreferably 12 V to 15 V, and, for example, about 14 V. Alternatively, the 14 V voltage source can also have higher voltagesfor example, from 35 V to 45 V, and in particular 42 V. If a current flows through the heating element 6, the heating wires are heated as a result of their electrical resistance and Joule heat generation. The region of the laminated pane 1 in which the heating element 6 is arranged can thus be freed quickly and efficiently from icing and fogging.

[0118] The projection arrangement 100 furthermore comprises a display device 10 arranged in the dashboard 9 as an image generator. The display device 10 is used to generate light 12 (image information) which is directed onto the reflective layer 11 and is reflected by the reflective layer 11 as reflected light 12 into the vehicle interior 14, where it can be seen by a viewer, e.g., a driver. The reflective layer 11 is suitably designed to reflect the light 12 of the display device 10, i.e., an image of the display device 10. The light 12 of the display device 10 preferably impinges upon the laminated pane 1 at an angle of incidence of 50? to 80?in particular, 60? to 70?, and, typically, approximately 65?as is customary for HUD projection arrangements. It would also be possible, for example, to arrange the display device 10 in the A-pillar of a motor vehicle or on the roof (in each case inside the vehicle) if the reflective layer 11 is suitably positioned for this purpose. If several reflective layers 11 are provided, a separate display device 10 can be assigned to each reflective layer 11, i.e., several display devices 10 can be arranged. The display device 10 is, for example, a display such as an LCD display, OLED display, EL display, or ?LED display. It would also be possible, for example, for the laminated pane 1 to be a roof panel, side pane, or rear pane.

[0119] The variant shown in FIG. 2 corresponds substantially to the variant from FIGS. 1 and 1a, so that only the differences will be discussed here, and reference is otherwise made to the description relating to FIGS. 1 and 1a.

[0120] Unlike in FIGS. 1 and 1a, the reflective layer 11 in FIG. 2 extends over the entire surface of the outer side III of the inner pane 3 and is applied thereto. Unlike as shown here, however, it is also possible for the reflective layer 11 to be applied to the inner side IV of the inner pane 3. The reflective layer 11 is, for example, a metal coating which contains at least one thin-film stack with at least one silver layer and a dielectric layer. The reflective layer 11 is partially transparent to light, so that the reflective layer 11 reflects approximately 30% of the light 12 impinging upon it and shows a transmission for the light 12 of approximately 70%.

[0121] In this exemplary embodiment, the thermoplastic intermediate layer 4 consists solely of the masking layer 5, which, in contrast to FIGS. 1 and 1a, is arranged not only in an edge region 13 of the laminated pane 1 between the outer pane 2 and the inner pane 3, but is arranged congruently on the entire inner side II of the outer pane 2 and the outer side III of the inner pane 3. The masking layer 5 has a transparent region 5 and an opaque region 5. It is, prior to the lamination, a coherent composite film, which is formed, for example, on the basis of polyvinyl butyral (PVB), ethylene vinyl acetate (EVA), and/or thermoplastic polyurethane (TPU), but is colored in a frame-shaped circumferential region 5 of the masking layer 5. The coloring is black, for example. However, the region 5 of the masking layer 5 within the frame-shaped circumferential section 5 is transparent, and can thus be seen through. The thickness of the masking layer 5 is, for example, 0.76 mm. When looking through the laminated pane 1, the first masking strip 7 is applied to be congruent with the opaque region 5 of the masking layer 5 on the inner surface II of the inner pane.

[0122] The opaque region 5 of the masking layer 5 is widened in the lower (motor-side) section 13 of the edge region 13, i.e., the opaque region 5 has a greater width in the lower (motor-side) section 13 of the edge region 13 than in the upper (roof-side) section 13 of the edge region 13 (as in the lateral sections of the edge region 13, which cannot be seen in FIG. 2) of the laminated pane 1. Width is understood to mean the dimension of the opaque region 5 perpendicular to the lower edge of the inner and outer panes 2, 3.

[0123] In this exemplary embodiment, the heating element 6 could likewise be arranged in the upper roof-side section 13 within the opaque region 5 of the masking layer 5. In addition, in order to achieve a circumferential heating effect, the heating element 6 could also be arranged along the extension direction from the upper edge to the lower edge and in the side edge region.

[0124] Furthermore, several display devices 10 could be provided which irradiate, for example, the lower (motor-side) section 13 and the upper (roof-side) section 13 of the edge region 13 with visible light 12. For example, the display device 10 could be arranged such that a (partially) circumferential image is generated.

[0125] Because the reflective layer 11 extends over the entire outer side III of the inner pane 3, all regions of the laminated pane 1 can be used to reflect an image. It is possible to use further display devices which irradiate, for example, regions of the reflective layer 11 which are not overlapping with the opaque region 5 of the masking layer 5, i.e., are located, for example, in the see-through region of the laminated pane 1. Through this, the function of a head-up display can be used.

[0126] Reference is now made to FIGS. 3 through 6, in which enlarged cross-sectional views of various embodiments of the laminated pane 1 are shown. The cross-sectional views of FIGS. 3 through 6 correspond to intersection line A-A in the lower section 13 of the edge region 13 of the laminated pane 1, as indicated in FIG. 1a.

[0127] FIG. 3 shows an enlarged cross-sectional view in the edge region 13 of FIG. 1a. In the variant of the laminated pane 1 shown in FIG. 3, the completely opaque masking layer 5 is arranged between the outer pane 2 and the inner pane 3. In the example shown, the masking layer 5 is in direct material contact with the reflective layer 11 and the first masking strip 7. The reflective layer 11 is arranged on the outer side III of the inner pane 3. The light 12 from the display device 10 is reflected by the reflective layer 11 as reflected light 12 into the vehicle interior 14. The light 12, 12 can have an s- and/or p-polarization. Due to the angle of incidence of the light 12 on the laminated pane 1 near the Brewster angle, the p-polarized proportion of the light 12 is barely prevented from transmission through the inner pane 3. This variant has the advantage that a relatively large proportion of the incident p-polarized light 12 is reflected and subsequently, due to the fact that the angle of incidence equals the angle of reflection (indicated by a in FIGS. 3 through 6), can, largely unimpeded, pass through the inner pane 3 and into the vehicle interior 14. In addition, the image is clearly visible against the background of the opaque masking layer 5 with high contrast. Because of the first masking strip 7, the heating element 5 cannot be seen from the external environment 15. Also, due to the opaque masking layer 5, the heating element cannot be seen from the vehicle interior 14.

[0128] The heating wires of the heating element 6 are arranged with their extension direction orthogonally to the cross-sectional plane within the opaque masking layer 5. The individual heating wires are arranged at a distance of, for example, approximately 1 mm from one another from the lower to the upper sections of the enlarged cross-section.

[0129] The variants shown in FIGS. 4 through 6 correspond substantially to the variant from FIGS. 1, 1a, and 3, so that only the differences will be discussed here, and reference is otherwise made to the description relating to FIGS. 1, 1a, and 3.

[0130] Unlike as shown in FIG. 3, the reflective layer 11 in FIG. 4 is applied, not on the outer side III of the inner pane 3, but on the inner side IV of the inner pane 3. This variant has the advantage that the incident light 12 is not prevented by the transmission through the inner pane 3. It is also preferred for light 12 having a high proportion of s-polarized light, because it results in fewer double images caused by the reflection on the inner pane 3.

[0131] The variant of the laminated pane 1 shown in FIG. 5 differs from the variant of FIG. 3 only in that a highly-refractive coating 17 is arranged on the inner side IV of the inner pane 3. The highly-refractive coating 17 is applied, for example, by means of the sol-gel method and consists of a titanium oxide coating. Due to the higher refractive index (for example, 1.7) of the highly-refractive coating 17 compared to the inner pane 3, the Brewster angle, which is normally approximately 56.5? (for soda lime glass), can be changed, which simplifies the application and reduces the effect of disruptive double images caused by the reflection on the inner side IV of the inner pane 3.

[0132] The variant of the laminated pane 1 shown in FIG. 6 differs from the variant of FIG. 3 in that, in addition to the first reflective layer 11 on the outer side III of the inner pane 3, a further reflective layer 11 is arranged on the inner side IV of the inner pane 3. Moreover, the highly-refractive coating 17 is applied to the further reflective layer 11. This arrangement then offers great advantages if the reflective layers 11, 11 each reflect smaller proportions (<10%) of the incident light 12. The arrangement on both the outer side III and the inner side IV of the inner pane 3 improves the total reflection of the incident light 12. The highly-refractive coating 17 moreover contributes to avoiding disruptive double images caused by the reflection on the inner side IV of the inner pane 3.

[0133] In all exemplary embodiments, the reflective layer 11 is arranged on the vehicle interior side of the masking layer 5, i.e., the reflective layer 11 is located in front of the masking layer 5 when looking onto the inside of the laminated pane 1.

[0134] It results from the above embodiments that the invention provides an improved laminated pane for a projection arrangement, which enables a good image representation with high contrast. Undesired secondary images can be avoided. Due to the use of the heating element together with the laminated pane, the space in the dashboard region can be significantly reduced when installed in a vehicle, which can enable a leaner design in the vehicle interior. With the image presentation via the reflective layer in front of the masking layer, the display, which is usually attached to the dashboard, with speedometer, tachometer, warning indicator, and fuel gauge can be replaced. Heating of the laminated pane by the heating element replaces supply lines, which usually conduct air heated by engine heat to the windshield. Moreover, additional geometric degrees of freedom arise when designing the vehicle interior if the air outlet nozzles, which are usually mounted in a specific geometric relationship to the glazing, are omitted. The laminated pane according to the invention can be produced easily and cost-effectively using known production methods.

LIST OF REFERENCE SIGNS

[0135] 1 Laminated pane [0136] 2 Outer pane [0137] 3 Inner pane [0138] 4 Thermoplastic intermediate layer [0139] 5 Masking layer [0140] 5 Opaque region [0141] 5 Transparent region [0142] 6 Heating element [0143] 7 First masking strip [0144] 8 Second masking strip [0145] 9 Dashboard [0146] 10 Display device [0147] 11 Reflective layer [0148] 12, 12 Light [0149] 13, 13, 13 Edge region [0150] 14 Vehicle interior [0151] 15 External environment [0152] 16 Transparent layer [0153] 17 Highly-refractive coating [0154] 100 Projection arrangement [0155] I Outer side of the outer pane 2 [0156] II Inner side of the outer pane 2 [0157] III Outer side of the inner pane 3 [0158] IV Inner side of the inner pane 3 [0159] A-A Intersection line