DECORATIVE RADOME AND METHOD OF PRODUCING THE SAME

Abstract

The invention is directed to a method of producing a decorative radome, comprising providing a substrate having a first surface and a second surface; applying, to at least a portion of the second surface of the substrate, a decorative layer comprising a layer of a metal or an alloy comprising a metal and a metalloid; and overmolding at least the decorative layer with a radio-transmissive polymer to provide an overmolded layer as well as a decorative radome comprising a first layer comprising a, preferably radio-transmissive, polymer, the first layer having a front surface; a second layer comprising a, preferably radio-transmissive, polymer, the second layer having a rear surface; and a decorative layer, between at least a portion of the first and second layer, comprising a layer of metal or an alloy comprising a metal and a metalloid, wherein the second layer directly or indirectly abuts the decorative layer and is directly adhesion bound or indirectly connected to the first layer, and wherein at least one of the first or second layers is comprised of a polymer capable of being formed by overmolding at a barrel nozzle temperature below 300 degrees Celsius.

Claims

1. A method of producing a decorative radome, comprising: providing a substrate having a first surface and a second surface; applying, to at least a portion of the second surface of the substrate, a decorative layer comprising a layer of a metal or an alloy comprising a metal and a metalloid; and overmolding at least the decorative layer with a radio-transmissive polymer to provide an overmolded layer.

2. The method according to claim 1, wherein the substrate is radio-transmissive and/or once set, the overmolded layer provides a third surface which is substantially parallel to the first surface of the transparent and/or radio-transmissive substrate, over at least a portion of the radome, the portion defining a signal path.

3. The method according to claim 1, wherein the radio-transmissive substrate and the decorative layer are heated prior to overmolding.

4. The method according to claim 3, wherein the radio-transmissive substrate and the decorative layer are heated prior to overmolding to at least 70 degrees Celsius, or to at least 80 degrees Celsius.

5. The method according to claim 1, wherein the decorative layer is applied to only a portion of the radio-transmissive substrate to form a visual feature.

6. The method according to claim 1, wherein the radio-transmissive substrate comprises a relieved portion or an elevated portion on the second surface of the substrate.

7. The method according to claim 6, wherein the decorative layer is applied to the relieved portion or the elevated portion.

8. The method according to claim 6, wherein the relieved portion is provided by a recess toward the first surface or the elevated portion is provided by a projection extending away from the first surface.

9. The method according to claim 1, wherein the radio-transmissive substrate is masked to limit the area of application of the decorative layer to only a portion of the second surface of the radio-transmissive substrate.

10. The method according to claim 1, wherein the radio-transmissive substrate is formed by injection moulding.

11. The method according to claim 1, wherein one of either the radio-transmissive substrate or the overmolded layer is substantially transparent to visible light.

12. The method according to claim 1, wherein one of either the radio-transmissive substrate or the overmolded layer is substantially opaque to visible light.

13. The method according to claim 1, wherein the radio-transmissive substrate is substantially transparent to visible light.

14. The method according to claim 1, wherein the radio-transmissive substrate is formed of polycarbonate.

15. The method according to claim 1, wherein the overmolding is performed with a barrel nozzle temperature below 300 degrees Celsius.

16. The method according to claim 1, wherein the overmolded layer and/or the radio-transmissive substrate is/are formed and/or at least partly comprised of at least one of: Acrylonitrile Ethylene Styrene (AES), Acrylonitrile butadiene styrene (ABS), polycarbonate (PC), high-flow AES or acrylonitrile-(ethylene-propylene-diene)-styrene (AEPDS), a blend of thermoplastics, or PC-ABS blended thermoplastic.

17. The method according to claim 1, wherein the decorative layer is a reflective layer.

18. The method according to claim 17, wherein the reflective layer is at least 35% reflective or photopic reflective, or at least 45% reflective or photopic reflective, or at least 50% reflective or photopic reflective, or at least 55% reflective or photopic reflective.

19. The method according to claim 1, wherein the decorative layer is applied by physical vapour deposition.

20. The method according to claim 19, wherein the physical vapour deposition is vacuum deposition or magnetron sputtering.

21. The method according to claim 1, wherein the decorative layer comprises indium, tin or an alloy comprising a metal and germanium and/or silicon.

22. The method according to claim 1, wherein the decorative layer comprises an alloy of aluminium and germanium and/or silicon.

23. The method according to claim 21, wherein the alloy comprises germanium, and wherein the concentration of germanium is at least 25 wt % germanium, or at least 40 wt % germanium, or at least 45 wt % germanium, or at least 50 wt % germanium, or at least 55 wt % germanium.

24. The method according to claim 21, wherein the alloy of germanium includes silicon.

25. The method according to claim 1, wherein the average thickness of the decorative layer is 20 to 190 nm thick, or 40 to 170 nm thick, or 60 to 150 nm thick.

26. The method according to claim 1, wherein the decorative layer acts at least partly as a frequency selective surface bandpass filter and/or comprises at least one repetitive pattern, wherein the pattern comprises crosses, circles, squares, stars, rectangles, lines, hexagons, ellipsoids, polygons, annulus, semicircles, circular sectors, triquetra, lune, arbelos, spiral, lemniscates and/or oval forms.

27. The method according to claim 26, wherein the frequency selective surface bandpass filter is produced by structuring of the decorative layer after its application preferably by laser etching.

28. The method according to claim 1, further comprising applying at least one intermediate layer to at least a portion of the second surface of the radio-transmissive substrate and/or at least a portion of the decorative layer.

29. The method according to claim 28, wherein the intermediate layer provides at least one functionality to the radome, a visual feature, a decorative feature, in addition to the decorative layer and/or the visual feature, at least one lighting and/or illumination functionality, at least one heating functionality and/or at least one cleaning functionality.

30. The method according to claim 28, wherein at least two sublayers are applied, wherein by each of the sublayers at least partly at least one of the functionalities is provided.

31. The method according to claim 28, wherein the intermediate layer preferably at least one of the sublayers is applied depending on the functionality provided by the intermediate layer and/or sublayer prior to applying or after applying the decorative layer.

32. The method according to claim 28, wherein the intermediate layer is applied depending on the functionality provided by the intermediate layer and/or sublayer; to the substrate and/or to the decorative layer.

33. The method according to claim 28, wherein the intermediate layer comprises at least one fibre optical device, wherein the fibre optical device directs and/or emits light through and/or into the radome or at least partly in the area of the decorative layer, the visual feature and/or the decorative feature.

34. The method according to claim 33, wherein the fibre optical device comprises at least one fibre optic string layered and/or embedded in the at least on intermediate layer and/or sublayer in form of at least one polymer film.

35. The method according to claim 34, wherein the embedding comprises laminating, ultrasonic embedding and/or thermally embedding.

36. The method according to claim 33, wherein the sublayer is at least partly formed by the film and/or the film is provided with at least one adhesive promoter on at least one surface, the intermediate layer and/or the sublayer.

37. The method according to claim 28, wherein the intermediate layer, the sublayer and/or the film comprising at least partly the fibre optical device is/are at least partly located within the recess, on the elevated portion and/or onto the decorative layer, wherein the decorative layer has a transmission of less then 15%, less than 10%, and/or the location comprises thermo forming and/or vacuum forming of the intermediate layer, the sublayer and/or the film.

38. The method according to claim 28, comprising optically connecting of the fibre optic device with at least one light engine via at least one connection element, wherein the connection element, preferably comprising a light guide and/or fibre optical strings, is it at least partly located in and/or connected to the intermediate layer, the sublayer, the film and/or the overmolded layer and/or optically connecting the substrate with the light engine.

39. The method according to claim 33, wherein the fibre optical device and/or the connection element is/are at least partly made of at least one dielectric material, glass and/or a polymer.

40. The method according to claim 28, comprising embedding at least one heating pad and/or at least one heating wire in the intermediate layer, in at least one of the sublayers and/or the film, wherein the embedding of the heating wire comprises at least partly melting of the intermediate layer, the sublayer and/or the film, ultrasonic, thermally, thermosonically and/or mechanically melting, using compression.

41. The method of claim 28, wherein the intermediate layer is printed or pad printed.

42. The method of claim 28, wherein the intermediate layer is coloured and/or masks application of the decorative layer on the radio-transmissive substrate.

43. The method according to claim 28, wherein the method further comprises applying at least one cladding layer to the second surface before applying the masking intermediate layer, wherein the cladding layer is at least one sublayer and/or additionally masks application of the decorative layer.

44. The method according to claim 1, further comprising the step of applying a hard-coat to the second surface of the radio-transmissive substrate.

45. The method according to claim 1, further comprising applying a hard-coat to the first surface of the radio-transmissive substrate and/or or applying a hard-coat to the overmolded layer the third surface, the intermediate layer, the sublayer and/or the film.

46. The method according to claim 44, wherein the hard-coat is at least 6 μm thick and/or has a maximum thickness of 28 μm thick.

47. The method according to claim 44, wherein the hard-coat is comprising one or more abrasion resistant layers comprising a material selected from the group consisting of an organo-silicon, an acrylic, a urethane, melamine and an amorphous SiOxCyHz.

48. A decorative radome comprising: a first layer comprising a radio-transmissive polymer, the first layer having a front surface; a second layer comprising a radio-transmissive polymer, the second layer having a rear surface; and a decorative layer, between at least a portion of the first and second layer, comprising a layer of metal or an alloy comprising a metal and a metalloid, wherein the second layer directly or indirectly abuts the decorative layer and is directly adhesion bound or indirectly connected to the first layer, and wherein at least one of the first or second layers is comprised of a polymer capable of being formed by overmolding at a barrel nozzle temperature below 300 degrees Celsius.

49. The decorative radome according to claim 48, further including an intermediate layer between at least a portion of the first layer and the second layer.

50. The decorative radome according to claim 49, wherein the intermediate layer is ink.

51. The decorative radome according to claim 49, wherein the intermediate layer provides at least one functionality to the radome, the visual feature, a decorative feature, in addition to the decorative layer, at least one lighting and/or illumination functionality, at least one heating functionality and/or at least one cleaning functionality.

52. The decorative radome according to claim 48, wherein the intermediate layer comprises at least two, wherein each of the sublayers provides at least partly at least one of the functionalities or respective different functionalities.

53. The decorative radome according to claim 48, wherein the intermediate layer is located, depending on the functionality provided by the intermediate layer and/or sublayer, between the first layer and the decorative layer or between the decorative layer and the second layer.

54. The method according to dam 48, wherein the intermediate layer is located, depending on the functionality provided by the intermediate layer and/or sublayer, on the substrate and/or on the decorative layer.

55. The decorative radome according to claim 48, wherein the intermediate layer, comprises at least one fibre optical device, wherein the fibre optical device allows to direct and/or emit light through and/or into the radome, at least partly in the area of the decorative layer, the visual feature and/or the decorative feature.

56. The decorative radome according to claim 55, wherein the fibre optical device comprises at least one fibre optic strings, layered and/or embedded in the at least on intermediate layer and/or sublayer, in form of at least one polymer or film.

57. The decorative radome according to claim 56, wherein the sublayer at least partly comprises the film and/or at least one adhesive promoter is located on at least a part of at least one surface or both surfaces of the film, the intermediate layer and/or the sublayer.

58. The decorative radome according to claim 49, wherein the intermediate layer, the sublayer and/or the film comprise(s) at least partly the fibre optical device and/or is/are at least partly located within the relived portion, on the elevated portion and/or on the decorative layer, wherein the decorative layer has a transmission of less then 15% or less than 10%, and/or the location comprises thermo forming and/or vacuum forming of the intermediate layer, the sublayer and/or the film.

59. The decorative radome according to claim 49, comprising at least one light engine, or LED light engine, optically connected to the fibre optic device via at least one connection element, wherein the connection element it at least partly located in and/or connected to the intermediate layer, the sublayer, the film, the first layer and/or the second layer and/or optically connected to the first layer or the front surface.

60. The decorative radome according to claim 55, wherein the fibre optical device and/or the connection element comprise(s) at least one dielectric material, glass and/or a polymer.

61. The decorative radome according to claim 49, wherein the intermediate layer comprises at least one or a plurality of heating wires, and/or at least one heating pad, wherein the heating wire is embedded in the intermediate layer and/or the sublayer by partly melting of the intermediate layer and/or the sublayer.

62. The decorative radome according to claim 61, wherein the heating wire is embedded in a pattern, the wire forms at least one frequency selective surface band pass filter, and/or the wire has at least partly a diameter of less than 60 microns, less than 40 microns, or less than 30 microns, wherein the band pass filter is radio-transmissive.

63. The decorative radome according to claim 49, wherein the intermediate layer or the sublayer comprises at least one piezoelectric element allowing the generation of ultrasonic waves and/or sound.

64. The decorative radome according to claim 49, wherein the intermediate layer, the sublayer and/or the film is/are coloured and/or is not substantially overlaid with the decorative layer.

65. The decorative radome according to claim 48, further comprising at least one cladding layer being at least partly located between the masking, intermediate layer and the first layer.

66. The decorative radome according to claim 48, further comprising a hard-coat layer.

67. The decorative radome according to claim 66, wherein the hard-coat layer covers at least a portion of the front surface of the first layer, is between at least a portion of the first layer and the decorative layer and/or covers at least a portion of the rear surface of the second layer.

68. The decorative radome according to claim 48, wherein the front surface and the rear surface of the radome are substantially parallel, over at least a portion of the decorative radome defining a radio path.

69. The decorative radome according to claim 48, wherein the decorative layer is a reflective layer.

70. The decorative radome according to claim 69, wherein the reflective layer is at least 35% reflective or photopic reflective, or at least 45% reflective or photopic reflective, or at least 50% reflective or photopic reflective, or at least 55% reflective or photopic reflective.

71. The decorative radome according to claim 48, wherein the decorative layer comprises indium, tin or an alloy comprising a metal and germanium and/or silicon.

72. The decorative radome according to claim 48, wherein the decorative layer comprises an alloy of aluminium and/or germanium and/or silicon.

73. The decorative radome according to claim 71, wherein the alloy comprises germanium, and wherein the concentration of germanium is at least 25 wt % germanium, or at least 40 wt % germanium, or at least 45 wt % germanium, or at least 50 wt % germanium, or at least 55 wt % germanium.

74. The decorative radome according to claim 71, wherein the decorative layer is 20 to 190 nm thick, or 40 to 170 nm thick, or 60 to 150 nm thick.

75. The decorative radome according to claim 48, wherein at least a portion of the front surface of the first layer and/or at least a portion of the rear surface of the second layer has a hard-coat.

76. The decorative radome according to claim 66, wherein the hard-coat is at least 6 μm thick and/or has a maximum thickness of 28 μm thick.

77. The decorative radome according to claim 66, wherein the hard-coat comprises one or more abrasion resistant layers comprising a material selected from the group consisting of an organo-silicon, an acrylic, a urethane, melamine and a SiOxCyHz.

78. The decorative radome according to claim 48, wherein one or both of the first and/or second layers is/are formed of Acrylonitrile Ethylene Styrene (AES), Acrylonitrile butadiene styrene (ABS), polycarbonate (PC), high-flow AES or acrylonitrile-(ethylene-propylene-diene)-styrene (AEPDS), a blend of thermoplastics, or PC-ABS blended thermoplastic.

79. The decorative radome according to claim 48, wherein one or both of the first and/or second layers is/are formed of polycarbonate.

80. A decorative radome produced according to a method of claim 1, wherein the radome does not substantially attenuate electromagnetic frequencies of 10 MHz-3000 GHz.

81. A decorative radome produced according to a method of claim 1, wherein the radome has a radio wave signal attenuation less than 2 dB (one way) across a signal path, or less than 1 dB (one way) across a signal path.

82. A decorative radome produced according to a method of claim 1, wherein the decorative layer has a sheet resistivity greater than 10.sup.6 ohms per square.

83. A decorative radome produced according to a method of claim 1, wherein there is no water ingress between the first layer and the second layer when the radome is immersed in water at 60° C. for 240 hours.

84. A method of producing a decorative radome, comprising: providing a substrate having a first surface and a second surface; applying, to at least a portion of the second surface of the substrate, a decorative layer comprising a layer of a metal or an alloy comprising a metal and a metalloid; and overmolding at least the decorative layer with a radio-transmissive polymer to provide an overmolded layer, wherein the radio-transmissive substrate and the decorative layer are heated prior to overmolding, to at least 70 degrees Celsius, and wherein the overmolding is performed with a barrel nozzle temperature below 300 degrees Celsius.

85. A method of producing a decorative radome, comprising: providing a substrate having a first surface and a second surface; applying, to at least a portion of the second surface of the substrate, a decorative layer comprising a layer of a metal or an alloy comprising a metal and a metalloid; and overmolding at least the decorative layer with a radio-transmissive polymer to provide an overmolded layer, wherein the decorative layer is applied by physical vapour deposition, and the average thickness of the decorative layer is 20 to 190 nm thick.

86. A method of producing a decorative radome, comprising: providing an injection moulded polycarbonate substrate having a first surface and a second surface; applying, to at least a portion of the second surface of the substrate, a decorative layer by coating the second surface of the substrate with a reflective layer in form of a layer of a metal with 99.9 wt % Indium; and overmolding at least the decorative layer with a radio-transmissive polymer to provide an overmolded layer, wherein the substrate is heated, the heated substrate is loaded into a second-shot injection mould tool and the overmolded layer is provided by a second shot injection of opaque Acrylonitrile Ethylene Styrene (AES) onto the second surface of the substrate, at a barrel temperature of 225° C. such that the overmolded layer covers the reflective layer on the substrate and the uncoated second surface of the substrate, thereby encapsulating the coating, to provide the decorative radome.

87. A decorative radome comprising: a first layer comprising a, preferably radio-transmissive, polymer, the first layer having a front surface; a second layer comprising a, preferably radio-transmissive, polymer, the second layer having a rear surface; and a decorative layer, between at least a portion of the first and second layer, comprising a layer of metal or an alloy comprising a metal and a metalloid, wherein the second layer directly or indirectly abuts the decorative layer and is directly adhesion bound or indirectly connected to the first layer, wherein at least one of the first or second layers is comprised of a polymer capable of being formed by overmolding at a barrel nozzle temperature below 300 degrees Celsius, and wherein the decorative radome further includes an intermediate layer between at least a portion of the first layer and the second layer, wherein the intermediate layer is ink, and/or provides at least one functionality, in form of at least one lighting and/or illumination functionality, at least one heating functionality and/or at least one cleaning functionality, and/or is colored, and/or is not substantially overlaid with the decorative layer.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0082] For a further understanding of the aspects and advantages of the present invention, reference should be made to the following drawings, taken in conjunction with the accompanying detailed description.

[0083] FIG. 1 is a flow diagram of an example of a method of manufacturing a radome, in accordance with the present invention.

[0084] FIG. 2 is a cross-section of an example of a radome in accordance with the present invention.

[0085] FIG. 3 is a cross-section of an example of a radome in accordance with the present invention including an intermediate layer, preferably playing a decorative role.

[0086] FIG. 4 is a cross-section of an example of a radome in accordance with the present invention including an alternative intermediate layer, preferably providing lighting and/or illumination function

[0087] FIG. 5 is a cross-section of an example of a radome in accordance with the present invention including a further alternative intermediate layer, preferably providing lighting and/or illumination function.

[0088] FIG. 6 is a cross section of the detail A in FIG. 5

[0089] FIG. 7 is a view onto the radome of FIG. 5.

[0090] FIG. 8 is a cross section of a further example of a radome in accordance with the invention in which the substrate and first layer is used as light pipe to illuminate the radome.

DETAILED DESCRIPTION

[0091] Radar systems in vehicles typically use microwaves to provide line-of-sight detection of objects. The three frequencies currently being used are 24 GHz, 77 GHz and 79 GHz. Primarily, 77 GHz and 79 GHz are used in vehicles as they offer improved range and resolution compared to the 24 GHz frequency. Attenuation of radio-waves increases as the frequency increases, and therefore the microwaves used in automotive radar systems are, by design, susceptible to attenuation. This however provides a problem for radomes, as they need to form a uniform surface with minimal attenuation of the transmitted and received radio signals. Essentially, a radome needs to be transparent to microwave electromagnetic radiation, and also provide minimal refraction, while ideally being visibly opaque and attractive.

[0092] The present invention provides a method for producing a decorative radome, and a decorative radome itself, which can be used for a vehicle, which includes a decorative layer (24), but has minimal attenuation of radiowave frequencies typically used for automotive purposes, particularly the 77 GHz and the 79 GHz frequencies. Further, it is desirable that the radome meets the visual requirement and durability requirements for use as a decorative automotive badge.

[0093] Specifically, the method of producing a decorative radome is illustrated in FIG. 1 and includes the steps of (1) preparing or providing a (radio-transmissive) substrate. The radio transmissive substrate will have a first surface (22) and a second surface (23—see FIG. 2). The method further includes (5) applying a decorative layer (24) to a portion of the second surface (23) of the substrate (21), preferably a portion including the relieved portion (25), wherein the decorative layer (24) comprising a metal or an alloy comprising a metal and a metalloid. Subsequently, the method further includes (7) overmolding at least the decorative layer (24) with a radio-transmissive polymer to provide an overmolded layer (26).

[0094] The term “second surface” as used in the context of the invention relates to a surface upon which a decorative layer (24) may be applied and which may be overmolded. The term “first surface” is used in opposition to the second surface. In one form, the radio-transmissive substrate (21) is substantially transparent when formed and will provide the front most surface of the radome, when in use. In this context the term “first surface” relates to the forward most surface of the substrate (21), when viewed. As such, and in the context of an automotive badge, the first surface (22) will be the front surface of the radio-transmissive substrate (21) of the badge when viewed from the front of the automobile.

1—Provide/Prepare Substrate

[0095] The radio-transmissive substrate (21) can be provided by any desired method. In some embodiments, the substrate (21) is injection moulded to form the desired shape. In some embodiments, the substrate (21) may be received already formed. Preferably, the substrate (21) includes a relieved portion (25) defining a three-dimensional visual feature on the second surface (23) of the substrate (21). The relieved portion (25) may be provided by a recess toward the first (22) surface of the substrate (21).

[0096] The substrate (21) and overmolded layer (26) can be formed of any suitable material, but is preferably a plastic. As would be understood in the art, radio-transmissive substrates are typically resistant to electrical conductivity (i.e. are insulating or are a dielectric). Suitable plastics and/or polymers for the substrate (21) or overmolded layer (26) include Acrylonitrile Ethylene Styrene (AES), Acrylonitrile butadiene styrene (ABS), polycarbonate (PC), high-flow AES, acrylonitrile-(ethylene-propylene-diene)-styrene (AEPDS), blends of thermoplastics, or PC-ABS blended thermoplastic. In some embodiments, the substrate (21) will be formed of Polycarbonate.

[0097] Importantly, one of either the substrate (21), or the overmolded layer (26), is substantially transparent. This allows viewing of the decorative layer (24) through the transparent layer. Preferably, the other layer is substantially opaque to visible light. The opaque layer masks the equipment positioned behind the radome, and can modify, or improve, the visual aspects of the decorative layer (24). For example improve the colour, or reflectivity, of the decorative layer (24) by minimising light transfer through the decorative layer (24). In use, for example when a radome in accordance with the invention (such as a radome produced by the method of the invention) is fitted as a badge on a car, the transparent layer forms the outermost (forward) layer. In a preferred embodiment, the radio-transmissive substrate (21) is transparent and the overmolded layer (26) is opaque.

2—Application of Intermediate Layer

[0098] In some embodiments, the method includes the step of providing an intermediate layer (29) and/or a plurality of sublayers of the intermediate layer to at least a portion of the second surface of the radio transmissive substrate (21). In some embodiments, the intermediate layer (29) and/or sublayers is/are applied prior to the application of the decorative layer (24) and can be applied prior to, or following on from, the deposition of a second surface coating (28) (in embodiments where one is applied).

[0099] The intermediate layer (29) and/or sublayers can be used to influence the appearance of the decorative radome produced by the method of the invention or might provide further functions as described with the help of FIGS. 4 to 8 below. The intermediate layer (29) can in one embodiment be a coloured layer which applies visual colour to the decorative radome. The intermediate layer (29) may also be a masking layer (which may be removable prior to overmolding or may be clear and remain in the decorative radome once produced) that assists in preventing application of the decorative layer (24) to unwanted portions of the radio-transmissive substrate (21). In such embodiments, the intermediate layer (29) and/or the sublayer is/are not substantially overlaid, or not overlaid, with the decorative layer (24) when the radome is completed. Such masking can be utilised when shadow masking during the application of the decorative layer (24) is difficult, or the appropriate details cannot be achieved by shadow masking. In some embodiments, the intermediate layer (29) could be an oil, liquid or ink mask, for example Fomblin™, Krytox™, SpeedMask™.

[0100] In preferred embodiments, the intermediate layer (29) is applied by printing. In some embodiments, the intermediate layer can withstand temperatures at or above 150° C., 175° C., 200° C., 220° C., 250° C., 275° C. or 300° C. for a minimum of 5, 10, 20, 30, 40 or 50 seconds, or 1, 1.5 or 2 minutes.

[0101] The intermediate layer (29) may be any suitable layer, and in a preferred embodiment the intermediate layer (29) is an ink, dye, oil, wax, lubricant or other suitable liquid or coloured film. In some embodiments, the intermediate layer is an ink. The ink can be deposited by any suitable method. In some embodiments, the intermediate layer (29) is printed. Printing methods may include dye diffusion thermal transfer, wax thermal transfer, indirect dye diffusion thermal transfer, screen printing, inkjet printing or gravure printing process such as pad printing. In some embodiments, the intermediate layer (29) is applied by pad printing.

[0102] Suitable methods are known in the art for printing on radio-transmissive substrates (21). For example, a thermo-stable ink such as Norilit™ U made by Procell, Inc. can be pad printed onto a three dimensional substrate, such as the radio transmissive substrate (21), and can tolerate temperatures up to 220° C. for more than two minutes. Other suitable inks and printing methods are known in the art, and can be used in the invention disclosed herein.

3—Apply Second Surface Coating (Optional)

[0103] In some embodiments, the method includes the further step of providing at least a portion of the second surface (23) of the radio-transmissive substrate (21) with a hard-coat (28). In such embodiments, the application of a hard-coat to at least a portion of the second surface (23) of the radio-transmissive substrate (21) may provide advantageous functions, including (but not limited to): increasing or influencing the bonding between the decorative layer (24) and/or intermediate layer (29) with the radio transmissive substrate (21); controlling the residual stress and/or thermal expansion of the decorative layer (24); tuning the colour, reflectivity or other visual appearance of the decorative layer (24) and/or intermediate layer (29); and/or providing an interface between portions of the radio-transmissive substrate (21) and the overmolded second layer (26) thereby influencing the adhesion bond between the two (without been an adhesive layer).

[0104] Suitable hard-coat layers (28) are described below under heading 7 “Applying Surface Coating(s)”.

4—Providing Shadow-Masking

[0105] Methods for applying decorative layers (24), such as physical vapour deposition (PVD), typically require masking to ensure that deposition of the material forming the decorative layer (24) is selectively applied to the radio-transmissive substrate (21). As such, the method of the present invention may include the step of (4) providing a shadow mask.

[0106] The shadow mask facilitates selective application of decorative layer (24) on the radio-transmissive substrate (21). The type of shadow mask used will depend on the technique used to apply the decorative layer (24). In some embodiments, the shadow mask is compatible with PVD, in particular sputtering and evaporation. In some embodiments, the shadow mask is stainless steel.

[0107] The shadow mask can be attached to each radio-transmissive substrate (21) prior to application of the decorative layer (24) or can be positioned within the deposition machine, such as on the target side of a PVD machine.

5—Application of Decorative Layer

[0108] The decorative layer (24) is applied only to a portion of the second surface (23) of the substrate (21) to provide a visual feature on the radio-transmissive substrate (21). In some embodiments, having a relieved portion (25) in the radio-transmissive substrate (21), the decorative layer (24) is applied to the relieved portion (25).

[0109] By applying the decorative layer (24) to only a portion of the substrate (21), this allows direct adhesion bonding between the first (radio-transmissive substrate) layer (21) and the (second) overmolded layer (26) in portions not provided with the decorative layer (24). In the absence of this direct adhesion binding between the substrate (21) and the overmolded layer (26), the layers may separate.

[0110] The decorative layer (24) is preferably a reflective layer, and includes any suitable metal, metalloid or metal/metalloid alloy that provides the desired reflectivity, or decorative appearance while being radio-transmissive. In some embodiments the metal which forms the decorative layer (24) includes transition metals. In some embodiments, the metal which forms the decorative layer (24) is Indium or Tin.

[0111] In some embodiments, a reflective layer is abutted by additional layers. In one embodiment, the reflective layer is between two layers of deposited Silicon. These multilayer stacks allow for tuning of the layer, including its colour and residual stress. In some embodiments, multiple layers, including a layer of Silicon followed by a layer of Aluminium/Silicon and then a further layer of Silicon, are deposited to the substrate (21) to form the decorative layer (24) prior to overmolding.

[0112] The importance of residual stress, the use of interfacing layers in controlling residual stress, and determination of residual stress parameters are described in WO2011/075796 and U.S. Pat. No. 9,176,256 B2, each entitled “PLASTIC AUTOMOTIVE MIRRORS”, and each of which is hereby incorporated by reference in its entirety for all purposes.

[0113] In some preferred embodiments, the decorative layer (24) includes a metalloid. Metalloids include Silicon, Boron, Germanium, Arsenic, Antimony and/or Tellurium. In specifically preferred embodiments, the metalloid is Silicon or Germanium. In a most preferred embodiment the metalloid is Germanium. Suitable metalloid/metal alloys include: Germanium and Aluminium and, optionally, Silicon; or Germanium and Silicon; or Germanium and Silver and, optionally, Silicon; or Germanium and Indium and, optionally, Silicon; or Aluminium and Silicon. In some embodiments, the alloy of Germanium is Germanium and Aluminium, or Germanium and Silicon, or Germanium and Aluminium and Silicon. In some embodiments, the alloy is Silicon and Aluminium.

[0114] When the metalloid/metal alloy includes Germanium, the alloy is at least 25 wt % germanium, or at least 40 wt % germanium, or at least 45 wt % germanium, or at least 50 wt % germanium, or at least 55 wt % germanium.

[0115] The decorative layer (24) is provided as a thin-coating layer. In some embodiments, the average thickness of the decorative layer (24) is 20-190 nm thick, or 40 to 170 nm thick, or 60 to 150 nm thick. Such thin-coatings can be provided by multiple methods in the art. However, preferably, the decorative layer (24), preferably a thin coating forming the decorative layer (24), is deposited by Physical Vapour Deposition (PVD). Suitable PVD methods include magnetron sputtering and evaporation, which may be resistive thermal evaporation or electron-beam evaporation. In some embodiments, the decorative layer (24) is deposited by magnetron sputtering.

[0116] Ideally, the moulding of the radio-transmissive substrate (21) (in embodiments whereby the radio-transmissive substrate is moulded), the application of any intermediate layers (29), and the application of the decorative layer (24) are performed in the same machine. Alternatively, each step can be performed by separate machines arranged to operate sequentially.

6—Heating Substrate and Decorative Layer

[0117] Prior to providing a second-shot overmolded layer (26), it may be advantageous to heat the substrate (21) and the decorative layer (24). Such heating (6) permits a degree of thermal expansion at a rate slower than that which will be encountered during the overmolding process (7) and as such will limit the rate of change in temperature of the decorative layer (24), and the substrate (21), during overmolding. This reduces visual defects, such as crazing, during the overmolding step (7). Therefore, in some embodiments of the method of invention, the substrate (21) and the decorative layer (24) are heated prior to overmolding. In some embodiments, the substrate (21) and the decorative layer (24) are heated to at least 70° C., or to at least 80° C. prior to the overmolding step (7).

7—Overmolded Layer

[0118] The overmolded layer (26), once set, provides a third (rear) surface (27) which is parallel or substantially parallel, to the first surface (22) of the radio-transmissive substrate (21), over at least a portion of the radome. The parallel or substantially parallel portion defining a radio path through which radio waves can traverse. Importantly, the parallel or substantially parallel nature of the first and third surface minimise difference in the refraction of the radio waves as they traverse different potions of the radio path of the radome.

[0119] Different thermoplastics/thermo-polymers have different flow temperatures and therefore require different barrel nozzles for injection moulding. Typically, higher temperatures will increase the likelihood of damage and visible defects in the decorative layer (24) when overmolded. Therefore, it is preferable to use thermoplastics/thermo-polymers with a relatively low nozzle temperature, or a nozzle temperature below the crazing point of the decorative layer (24).

[0120] The melt temperature and mould temperature for a range of common thermoplastics is provided in Table 1 below.

TABLE-US-00001 TABLE 1 Thermoplatics melt temperatures and desired mould temperatures. MELT MOULD TEMPERATURE TEMPERATURE RANGE (° C.) RANGE (° C.) ABS 190-270 40-80 ABS/PC ALLOY 245-265 40-80 ACETAL 180-210  50-120 AES 215-260 55-65 PMMA 220-250 50-80 CAB 170-240 40-50 HDPE 210-270 20-60 LDPE 180-240 20-60 NYLON 6 230-290 40-90 NYLON 6 (260% GF) 250-290 50-90 NYLON 6/6 270-300 40-90 NYLON 6/6 (263% GF) 280-300 40-90 NYLON 11 220-250  40-110 NYLON 12 190-200  40-110 PEEK 350-390 120-160 POLYCARBONATE 280-320  85-120 POLYESTER PBT 240-275 60-90 PET (SEMI CRYSTALLINE) 260-280 20-30 PET (AMORPHOUS) 260-280 20-30 POLYPROPYLENE 200-280 30-80 (COPOLYMER) POLYPROPYLENE 200-280 30-80 (HOMOPOLYMER) POLYPROPYLENE 240-290 30-50 (260% TALC FILLED) POLYPROPYLENE (260% GF) 250-290 40-80 POLYSTYRENE 170-280 30-60 POLYSTYRENE (260% GF) 250-290 40-80 PVC P 170-190 20-40 PVC U 160-210 20-60 SAN 200-260 50-85 SAN (260% GF) 250-270 50-70 TPE 260-320 40-70

[0121] Further specifications for thermoplastic materials are provided by the International Organisation for Standardization, and are particularly set forth in the Standards Catalogue 83.080.20.

[0122] In some embodiments, the overmolded layer (26) is formed with a barrel nozzle temperature at or below 300° C. In some embodiments, the barrel nozzle is at or below 280° C. during the overmolding process (7). In some embodiments, the barrel nozzle is at or below 250° C. during the overmolding process (7). In some embodiments, the barrel nozzle is at or below 230° C. during the overmolding process (7). Suitable polymers, which are capable of being injection moulded at these barrel nozzle temperatures are known in the art and are determined by their melt temperature.

8—Applying Surface Coating(s)

[0123] Further, some embodiments of the method of the invention include providing the first surface (22) of the radio-transmissive substrate (21) with a hard-coat (28). The inherent function of a radome is to provide protection to radar equipment from the environment. As such, the radome is susceptible to degradation, wear and damage. This exposure is further amplified when the radome is positioned at the front of a vehicle that is routinely exposed to relatively high speeds, abrasives, projectiles as well as chemicals used for cleaning. In this respect, a coating (28) that is said to be a “hard-coating” is a coating that is harder than the radio-transmissive substrate (21), whereby it increases the abrasion resistance of that radio-transmissive substrate (21).

[0124] Such an abrasion resistant hard-coating (28) is one that reduces damage due to impacts and scratching. Abrasion resistance can be measured through standard tests such as ASTM F735 “Standard Test Method for Abrasion Resistance of Transparent Plastics and Coatings Using the Oscillating Sand Method”, ASTM D4060 “Standard Test Method for Abrasion Resistance of Organic Coatings”, by the Taber Abrader, or by using the well-known Steelwool Test.

[0125] Furthermore, some plastics can be damaged by certain solvents; for example, polycarbonate is damaged by acetone. It is a requirement for many exterior automotive components, such as radomes, that they be “chemically resistant”, which is a reference to an ability to withstand exposure to normal solvents such as diesel fuel, petroleum, battery acid, brake fluid, antifreeze, acetone, alcohol, automatic transmission fluid, hydraulic oil and ammonia based window cleaners. In this respect, it will be appreciated that a hard-coating ideally provides at least the first surface of the radome with such chemical resistance.

[0126] A hard-coating (28) on the first (22) and/or second (23) surface of the radome and/or radio-transmissive substrate is preferably formed from one or more abrasion resistant layers, and may include a primer layer that bonds well to the substrate (21) and forms a preferable material and/or surface for subsequent abrasion resistant layers. The primer layer may be provided by any suitable material and may for example be an organic resin such as an acrylic polymer, a copolymer of acrylic monomer and methacryloxysilane, or a copolymer of a methacrylic monomer and an acrylic monomer having a benzotriazole group or benzophenone group. These organic resins may be used alone or in combinations of two or more.

[0127] The hard-coat layer(s) (28) are preferably formed from one or more materials selected from the group consisting of an organo-silicon, an acrylic, a urethane, a melamine or an amorphous SiO.sub.xC.sub.yH.sub.z.

[0128] Commercially available hard-coatings include Momentive PHC-587B, momentive UVHC 5000 (which is UV cured) and the two part product comprising a primer of PR6600 (SDC Technologies), subsequently coated with MP101 (SDC Technologies).

[0129] Most preferably, the hard-coat layer(s) (28) is/are an organo-silicon layer, due to its superior abrasion resistance and compatibility with physical vapour deposited films. For example, a hard-coating layer comprising an organo-silicon polymer can be formed of a compound selected from the following compounds: trialkoxysilanes or triacyloxysilanes such as,

methyltrimethoxysilane, methyltriethoxysilane, methyltrimethoxyethoxysilane, methyltriacetoxysilane, methyltripropoxysilane, methyltributoxysilane, ethyltrimethoxysilane, ethyltriethoxysilane, vinyltrimethoxysilane, vinyltriethoxysilane, vinyltracetoxysilane, vinyltrimethoxyethoxysilane, phenyltrimethoxysilane, phenyltriethoxysilane, phenyltriacetoxysilane, gamma-chloropropyltrimethoxysilane, gamma-chloropropyltriethoxysilane, gamma-chloropropyltripropoxysilane, 3,3,3-trifluoropropyltrimethoxysilane gamma-glycidoxypropyltrimethoxysilane, gamma-glycidoxypropyltriethoxysilane, gamma-(beta-glycidoxyethoxy)propyltrimethoxysilane, beta-(26,4-epoxycyclohexyl)ethyltrimethoxysilane, beta-(26,4-epoxycyclohexyl)ethyltriethoxysilane, gamma-methacryloxypropyltrimethyoxysilane, gamma-aminopropyltrimethoxysilane, gamma-aminopropyltriethoxysilane, gamma-meraptopropyltrimethoxysilane, gamma-mercaptopropyltriethoxysilane, N-beta(aminoethyl)-gamma-aminopropyltrimethoxysilane, beta-cyanoethyltriethoxysilane and the like; as well as dialkoxysilanes or diacyloxysilanes such as dimethyldimethoxysilane, phenylmethyldimethoxysilane, dimethyldiethoxysilane, phenylmethyldiethoxysilane, gamma-glycidoxypropylmethyldimethoxysilane, gamma-glycidoxypropylmethyldiethoxysilane, gamma-glycidoxypropylphenyldimethoxysilane, gamma-glycidoxypropylphenyldiethoxysilane, gamma-chloropropylmethyldimethoxysilane, gamma-chloropropylmethyldiethoxysilane, dimethyldiacetoxysilane, gamma-methacryloxypropylmethyldimethoxysilane, gamma-metacryloxypropylmethyldiethoxysilane, gamma-mercaptopropylmethyldimethoxysilane, gamma-mercaptopropylmethyldiethoxysilane, gamma-aminopropylmethyldimethoxysilane, gamma-aminopropylmethyldiethoxysilane, methylvinyldimethoxysilane, methylvinyldiethoxysilane and the like.

[0130] The hard-coat layer(s) (28) may be coated onto a substrate (such as the radio-transmissive substrate (21)) by dip coating in liquid followed by solvent evaporation, or by plasma enhanced chemical vapour deposition (PECVD) via a suitable monomer, flow coating or spray coating. To improve the abrasion resistance of the hard-coating (28), subsequent coatings of the hard-coating may be added, preferably within a 48 hour period to as to avoid aging and contamination of the earlier coatings. These additional coatings may be added to either the first (22) or second (23) surface of the substrate (21)

[0131] The thickness of the hard-coat layer (28) is preferably selected to assist in providing adequate abrasion resistance. The appropriate abrasion resistance will be determined by the required application and the demands of the user. In some applications, adequate abrasion resistance may be regarded as being a Bayer abrasion ratio of 5 with respect to an uncoated plastic substrate (21—such as a polycarbonate), or alternatively by a Taber abrasion test with delta haze less than 15% after testing with a 500 g load and CS10F wheel at 500 cycles, (% haze being measured as per ASTM D1003). With these requirements met, when an organo-silicon is used as a hard-coat layer (28), the thickness of the hard-coating (28) is preferably at minimum of at least 6 μm thick on average and/or has a maximum thickness of 28 μm thick.

[0132] Further coatings to those discussed above may be applied to the first surface of the radio-transmissive substrate, in addition to those discussed above, to modify the surface properties of the substrate. For example, a cap layer may also be provided by materials having characteristics, including: hydrophobic, hydrophilic, lipophobic, lipophilic and oleophobic or combinations thereof.

Decorative Radome

[0133] The invention further provides a decorative radome comprising; a first layer (21) comprising a radio-transmissive polymer, the first layer (21) having a front surface (22); a second layer (26) comprising a radio-transmissive polymer, the second layer (26) having a rear surface (27); and a decorative layer (24) between the first (21) and second (26) layer comprising a metal or an alloy comprising a metal and a metalloid, wherein the second layer (26) directly abuts the decorative layer (24) and the first layer (21) is directly adhesion bound to the second layer (26), and wherein at least one of the first (21) or second (26) layers is comprised of a polymer (thermo-polymer) capable of being overmolded at a barrel nozzle temperature below 300 degrees Celsius.

[0134] Further, the decorative radome of the invention can include a hard-coat (28) provided to the first surface (22) of the radome.

[0135] It is to be understood that the term “directly adhesion bound” is a reference to the physico-chemical phenomenon resulting from molecular attraction exerted between the first layer (21) in contact with the second layer (26), and is expressly considered to exclude bonds formed solely by adhesives.

[0136] The decorative radome of the invention does not substantially attenuate electromagnetic frequencies of 10 MHz to 3000 GHz. Specifically, in some embodiments, the radome has a radar attenuation less than 2 dB one-way (4 dB two-way) across a signal path, or preferably 1 dB one-way (2 dB two-way) across a signal path. Further, the decorative layer (24) comprising a metal or an alloy of metal and a metalloid, has a sheet resistivity greater than 10.sup.6 ohms per square (Ω/□).

[0137] Advantageously, the direct adhesion bond formed between the first layer (21) and the second layer (26) improves the weather resistance of the radome compared to radomes formed of layers bound by adhesives. Therefore, in some embodiments there is no water ingress between the first layer (21) and the second layer (24) when immersed in water at 60° C. for 240 hrs.

[0138] The decorative radome can be produced in accordance with the method disclosed above. Alternatively, the decorative radome can be produced by any suitable method that provides all of the required claimed features and functions. Importantly, the decorative radome of the invention should be considered to optionally include, the structural and functional features disclosed above in relation to the method.

[0139] The decorative radome of the present invention, or produced with the method of the present invention, can be used in any suitable context. In an embodiment the radome is a car badge. In some forms, the car badge may include additional features, functions and aesthetics. In some embodiments, the radome can be used in combination with a light assembly, or may include additional features, as that described in WO2017/009260 and US patent application publication number 2018/0202626 A1, each entitled “A LIGHT ASSEMBLY AND A VEHICLE DESIGN ELEMENT INCLUDING SUCH A LIGHT ASSEMBLY”, and each of which is hereby incorporated by reference in its entirety for all purposes.

[0140] In FIG. 4 a cross-section of an example of a radome (120) in accordance with the present invention including an alternative intermediate layer, preferably providing lighting and/or illumination function is shown. The radome (120) can preferably be formed by a method as described before with the help of FIG. 1. The radome (120) comprises a substrate (121). Similar to the radomes shown in FIGS. 2 and 3 the substrate (121) comprises a relieved portion (125) defining a three-dimensional additional feature on the second surface (123) of the substrate (121). Within the relieved portion (125) a decorative layer (124) similar to the decorative layer (24) described before is applied.

[0141] In addition to the decorative layer (24) and in contrast to the radomes shown in FIGS. 2 and 3 in the radome (120) an intermediate layer (129) is located. The intermediate layer (129) is formed by a firm comprising a fibre-optic device in form of fibre-optic strings. The intermediate layer (129) is connected via a connection element in form of a light guide (131) to a light engine (133), preferably comprising an LED device. The light guide (133) is reaching through the overmolded layer (126).

[0142] The light guide (131) as well as the light engine (133) are located outside a visual field (135) of a radar unit (137). Thus radiation emitted by or transmitted to the radar unit (137) is not negatively influenced by the light guide (131) or the light engine (133).

[0143] On the first of front surface (122) of the substrate (121) a protective hard-coat (130) is applied.

[0144] In FIG. 5 a slightly different a configuration of a radome (220) is shown. The elements of the radome (220) corresponding to the elements of the radome (120) have the same reference signs, however increased by 100. The main difference between the radome (120) and the radome (220) is the location and orientation of the light engine (233) and the light guide (231). As can be seen from FIG. 5 the light engine (233) can also be located on a side surface of the radome (220). In this way the distance of the light guide (231) and the light engine (233) to the radar unit (237), preferably a view field (235) of the radar unit (237) can be further increased.

[0145] In FIG. 6 a cross-section of the detail A in FIG. 5 is shown. As can be taken from the FIG. 6 within the relieved portion (125) of substrate (121) the decorative layer (124) is located. On the side of the decorative layer (124) facing the overmolded layer (126) the intermediate layer (129) is located. The intermediate layer (129) comprises a sub-layer (138) including fibre-optical devices in the form of fibre-strings and thus forming a fibre optic panel. On both sides of the fibre-optic panel (138) sub-layers in form of adhesive layers (139) are located. The light guide (131) is formed by fibre-optic strings extending all of the fibre-optic panel and or be connected to the fibre-optic panel (138). The fibre-optic panel (139) might be covered by a further reflective layer on the side facing the overmolded layer (126) such that light is only emitted in the direction of the arrows (141) into the substrate (121) in the direction of the surface (122) shown in FIG. 6. Thus light produced by the light engine (133) is conveyed through the light guide (133) to the fibre-optic panel (129) and from there it is emitted through the decorative layer (124) thus illuminating the area of the decorative layer (124).

[0146] In FIG. 7 a view onto the radome (220) of FIG. 5 is shown. As can be taken from the FIG. 7 the decorative layer (224) forms a visual feature in form of the character “I”. Due to the reflectivity of the decorative layer (224) the character I is reflective such that it can be seen well from the side of the radome opposite the radar unit (237). When the light engine (233) is actuated furthermore the decorative layer (224) and thus the visual feature is illuminated. It is preferred that outside the area of the relieved portion (225) an intermediate layer in form of masking is provided such that the light guide (231) as well as the light engine (233) cannot be seen from outside.

[0147] In preferred embodiments the light guide as well as the light panel allows to illuminate the visual feature selectively or in different colours depending on the colour fed into the light guide (231) by the light engine (233).

[0148] FIG. 8 is a cross-sectional view of a further example of a radome (320). The elements of the radome (320) corresponding to the elements of the radome (120) have the same reference number however increased by 200. In comparison to the radomes shown in the FIGS. 2 to 7 the radome (320) is produced by an inventive method different from the method shown in FIG. 1.

[0149] The substrate (321) is produced in a first step. As can be seen from FIG. 8 the substrate (321) does not include a relieved portion but a projection (343). Before a decorative layer (324) is applied to the projection (343) a masking layer (345) is applied to the substrate outside the area of the projection (343).

[0150] In FIG. 8 furthermore before applying the masking layer (345) an optional cladding layer (347) has been applied to the substrate (321). After applying the masking layer (345) the decorative layer (324) is applied to the projection (343). In a next step the overmolded or second layer (326) is applied to the substrate (321), the masking layer (345) and the decorative layer (324). Finally an optional hard-coat (330) is applied to the overmolded layer (326).

[0151] As can be seen from a comparison of the radomes (120, 220) shown in FIGS. 4 to 7 and the radome (320) the radar unit (337) is located on the side of the radome (320) at which the substrate (321) is located. This allows to use the substrate (321) as a light pipe to illuminate the decorative layer (324).

[0152] The purpose of the light pipe is to transmit light from the light engine (333) (in FIG. 8 two light engines are shown, especially generating light of different colours, although only one light engine (333) might be used) out through the decorative layer (324) to be viewed from the surface (349) representing a rear surface or third surface in the sense of the claims. The light pipe formed by substrate (321) has entry points for light produced the light engines (333), which sit adjacent to it.

[0153] The light engines (333) are optically connected to the substrate (321). The light coupled into the substrate (321) cannot emit to the overmolded layer (326) outside the area of the decorative layer (324) due to the masking layer (345). Thus when seen from the side of the overmolded layer (326) only the decorative layer (324) is illuminated. It is preferred that the masking layer (347) and/or the cladding layer (345) covers also die surfaces of the radome to avoid emission of light through these surfaces. For this purpose the masking layer (347) and/or the cladding layer (345) might extend also beyond the radar unit (337) and the light engines (333) or might encapsulate them.

[0154] Before providing a more detailed description of various preferred embodiments of the present invention, with reference to various examples, it will be useful to provide some explanation of some of the terminology used throughout the specification, the steps of the process for producing a decorative radome and the methods and parameters for environmental testing and compliance of a radome in accordance with the present invention.

[0155] The term “reflective” refers to reflection of visible light, typically in the nanometre wave length and frequency range of 400 to 800 THz. The percentage of reflectance can be measured using known techniques in the field, or as discussed below.

[0156] A reference to radio wave throughout the specification, typically refers to frequencies of 10 MHz to 3000 GHz. In preferred embodiments, and in relation to automotive vehicles, the frequency is typically 1000 MHz to 100 GHz. In some specific embodiments in relation to radomes for vehicles, the frequency is 24 GHz to 79 GHz, or 77 GHz to 79 GHz, 24 GHz, 77 GHz or 79 GHz.

[0157] The term “transparent” and “opaque” when used without a qualifier (such as “radio-wave” or “radar”) refers to visually transparent or opaque, and hence is a reference to transmission or absorption of visible light as defined above.

Radome Technical Characteristics

[0158] To minimise refraction of the radar signal, as it passes through the radome, the front and rear face should be parallel or substantially parallel. Further, the interior of the radome should have no voids, air bubbles or significant changes in material density such as water ingress, and the decorative layer should be of a uniform thickness.

[0159] The surface resistivity of the decorative layer can be determined using a four-point method, using a four-point probes in accordance with JIS K7194. Surface resistivity should be above 10.sup.6 Ω/□ (Ohms per square) indicating low electrical conductivity (i.e. the reflective layer is electrically insulated in situ).

[0160] Radio wave attenuation and reflectance will be determined by the requirements of the user, the application, the frequency used and the equipment being used. However, preferably there will be a minimum of 10 dB reflection and a maximum of 1 dB one-way (2 dB two-way) transmission loss at the sensor operating frequency, typically 24 GHz, 77 GHz or 79 GHz.

Environmental Performance and Testing

[0161] The product must meet automotive exterior performance requirements such as UV resistance, abrasion resistance, resistance to temperature cycling that may case crazing or delamination of the layers forming the radome, and resistance to ingress of fluids which will lead to significant diffusion, attenuation and refraction of traversing radio signals.

[0162] Acceptable standards will be set depending on the use of the radome, and the manufactures requirements. For example, the minimal standard and testing protocols for automotive purposes will be determined by the vehicle manufacturer.

[0163] The following provides non-limiting examples of testing protocols required by automotive manufacturers:

Environmental Testing

[0164] Heat test—1 h at 90° C. —Assessment: The parts must not show any noticeable deformations 2 hours after the test at RT. There must be no visible surface changes on the part and the contact surfaces (e.g. no discoloration or cracks).

[0165] Long term aging—Test cycle 42 days at 80° C. —Assessment: as above for heat test.

[0166] Temperature cycling test—10 cycles: 2 h—30° C. —Assessment: as above for heat test.

[0167] Cold test—2 h at 40° C. —Assessment: as above for heat test.

[0168] Bucket test—Green E1 container filled with water (containing surfactant), water level at 15 cm, water temperature 20° C.±5° C. —Immerse radome in the water containing surfactant for approximately 10 minutes. Remove and dry radome—Assessment: attenuation value may not exceed. ±0.3 dB deviate from the first measurement.

[0169] Cycle test of heating—Circulating air temperature: 1 h+5° C., 1 h cooling to −5° C., 1 h at −5° C., 1 h heating to +5° C.; Air flow 30 km/h—Test duration: 700 h—Assessment: No change of surface/optics, no wire-stripping or raising of individual layers. Radar attenuation value and electrical Resistance is within specification.

Mechanical Tests

[0170] Falling weight test—1) At room temperature and −25° C., a cylindrical pin with a mass of 250 g is dropped from a drop height of ≥0.8 m at RT and ≥0.6 m at −25° C. on a rib, trim or similar protruding feature on the radome. The diameter of the bolt is at the impinging surface 15 mm—Assessment: No breakage is allowed on the surface acted on by the bolt.

[0171] Engine hood endurance run—Execution: 5000 operations of the bonnet with a falling speed of 0.6-0.7 m/s, measured 500 mm behind the engine hoodwing point—Assessment: The structural strength of the radome must be guaranteed, it may not lose or break any parts. The contact surfaces of the parts and the fasteners must not cause any damage to the surrounding parts (danger of corrosion).

[0172] Disassembly/reassembly—The disassembly/reassembly of the radome from the vehicle must be performed at room temperature three times—Assessment: The fit of the individual parts and the installation of the radome on the vehicle must be guaranteed at room temperature with uniform gap formation without deformation, sink marks and clip marks. The risk of accidents and injury must be assessed. Easy handling of the parts during assembly must be guaranteed. The clips (snap hook) cannot break out during the dismantling of the part. The holding force of the clipping of the loaded parts must withstand the loads during driving and the car wash. The contact surfaces of the parts may not cause damage or discoloration on surrounding parts.

[0173] High pressure cleaning test—The test must be carried out in 2 different cleaning systems. Distance: approx. 50-100 mm. Test duration: 30 sec—Assessment: There must be no damage to the component and the surface. No change in the attenuation values.

Visual Characteristics

[0174] The visual characteristics and tolerable parameters will be dependent on the application of the radome and user requirements.

[0175] When the radome is developed for automotive applications the following considerations should be applied. The border between the reflective and non-reflective surfaces must be visually smooth and crisp. The reflectivity should match that of metal finishes, particularly associated metallic finishes in proximity to the radome.

[0176] The reflectivity should minimally be 35%, or more preferable greater than 45%. The colour space will be determined by the user, but preferably has the colour coordinates on L a b colour space of −1<a<1, −1<b<1 (1st surface & 2nd surface viewing). The reflectivity can be assessed on the basis of first surface viewing (i.e. viewing with the surface of application proximal to the testing apparatus or the “viewer”). Alternatively, reflectivity can be assessed on the basis of second surface viewing (i.e. viewing through a material with the surface of application of the decorative layer distal to the testing apparatus or the “viewer”). The terms “first surface viewing” and “second surface viewing” are not the be confused with reference to applications of coatings to the “first surface” or “second surface” as used and defined herein in relation to the method of producing a radome in accordance with the invention, or the radome per se.

[0177] Reflectivity can be measure using known techniques in the art including using the CIELAB colour scale, illuminate A, observer at 2 degrees.

[0178] Methods of producing a radome in accordance with the invention are describe by way of the following examples.

Example 1—Germanium/Aluminium Reflective Layer

Substrate Preparation

[0179] A polycarbonate substrate, formed by injection moulding was cleaned with a commercial ultrasonic cleaning system in the presence of a detergent. The cleaned substrate was rinsed in distilled water in a clean (dust free) environment, to provided substantially contamination free substrate.

[0180] The substrate is moulded to provide a relieved portion on the second surface to provide a visual feature, which may be subsequently coated as described below.

First Surface Hard-Coating

[0181] The clean substrate was spray-coated on the first surface with Momentive PHC-587B in solution. The first-surface coated substrate was left for 10 minutes to allow evaporation of the solvents until the surface was substantially tack-free. Subsequently, the first-surface coated substrate was cured for 45 minutes at 130° C. in a curing oven to provide a hard-coated substrate.

[0182] To avoid ageing and/or contamination of the substrate, the coated article was further processed as detailed below within 48 hours.

Second Surface Reflective Layer

[0183] A reflective layer was provided to the second surface of the substrate using the following process.

[0184] The hard-coated substrate was blown down with deionised air, selective shadow masks were applied to limit the area of deposition of subsequent coatings, and then the masked substrate was loaded into the coating sample chamber of a batch type vacuum chamber.

[0185] The sample chamber was evacuated to 1.5×10.sup.−5 mbar and the second surface of the substrate was coated with a reflective coating as detailed below.

[0186] The following were deposition conditions: [0187] Reflective layer—Target: Aluminium/Germanium (50 wt %) [0188] Argon: 400 sccm [0189] Pressure: 2.2 e.sup.−3 mbar [0190] Power: 30 kW [0191] Target to substrate distance:=110 mm [0192] Deposition time: 2 minutes [0193] Layer thickness: 70 nm

Overmolding of the Substrate

[0194] The second surface of the substrate, having a provided reflective layer, was overmolded with a second radio-transmissive polymer to provide an overmolded layer, using the protocol detailed below.

[0195] The coated substrate was loaded into a holding oven maintained at 75° C. for a minimum of 5 minutes to increase the temperature of both the substrate and the provided layer(s).

[0196] The heated substrate was then loaded into the second-shot injection mould tool. An overmolded layer was provided by a second shot injection of opaque Acrylonitrile Ethylene Styrene (AES) onto the second surface of the substrate, at a barrel temperature of 225° C. This overmolded layer covered the reflective layer on the substrate and the uncoated second surface of the substrate, thereby encapsulating the coating, to provide the decorative radome.

Assessment of the Radome

[0197] Environmental and Visual performance of the radome was assessed using the following techniques. [0198] Humidity ageing: [0199] Place the radome into environmental chamber at 40° C. and 95% relative humidity for a period of 1000 h. [0200] Thermal shock: [0201] Subject the radome to 200 cycles of −40° C. to +85° C. at the rate of 1 h/cycle with a change period of <30 s. [0202] Thermal Cycle: [0203] Subjected the radome to 10 cycles of; 75°±2° C. for 4 h; to 38°±2° C., 95%±5% relative humidity for 16 h; to −30°±2° C. for 4 h. [0204] Cold Temperature ageing: [0205] Place the radome into a freezer at −40° C. for a period of 240 h [0206] High temperature ageing: [0207] Place the radome in an oven, ageing conditions: 80±2° C. for 1000 h

[0208] The result are provided in Table 2, below:

TABLE-US-00002 TABLE 2 Results Description Result Photopic reflectivity 2.sup.nd surface viewing 50% Appearance Coating free of defects One way radar attenuation 76-77 GHz <2 dB Humidity Ageing (40° C., 95% RH, 500 hrs) Pass Thermal Shock Pass Thermal Cycle Pass Cold Temperature ageing Pass High Temperature ageing (80° C., 500 hrs) Pass

Example 2—Aluminium/Silicon Reflective Layer

Substrate Preparation and Hard-Coating

[0209] An injection moulded polycarbonate substrate was prepared and provided with a first surface hard-coat as describe above in Example 1, with the exception that the substrate was selectively dip coated on the first surface and portions of the second surface using a mask, such that the portion of the second surface designated for deposition of the reflective layer are provided with a hard-coat.

Second Surface Reflective Layer

[0210] The hard-coated substrate was prepared for coating with a reflective layer as described in Example 1. The reflective layer was deposited using the following conditions: [0211] Reflective layer—Target: Aluminium/Silicon (60:40 wt %) [0212] Argon @ 20 sccm [0213] Pressure=4 e.sup.−3 mbar [0214] Power @ 700 W [0215] Target to substrate distance=110 mm [0216] Deposition time=13 minutes [0217] Thickness=50 nm

Overmolding of the Substrate

[0218] The second surface of the substrate, having a provided reflective layer, was overmolded with a second radio-transmissive polymer to provide an overmolded layer, using the protocol detailed below.

[0219] The coated substrate was loaded into a holding oven maintained at 80° C. for a minimum of 5 minutes to increase the temperature of both the substrate and the provided layer(s).

[0220] The heated substrate was then loaded into the second-shot injection mould tool. An overmolded layer was provided by a second shot injection of opaque Acrylonitrile Butadiene Styrene (ABS) onto the second surface of the substrate, at a barrel temperature of 245° C. This overmolded layer covered the reflective layer on the substrate and the uncoated second surface of the substrate, thereby encapsulating the coating, to provide the decorative radome.

Assessment of the Radome

[0221] Environmental and Visual performance of the radome was assessed using the techniques described above, with the following result:

TABLE-US-00003 TABLE 3 Results Description Result Photopic reflectivity 2.sup.nd surface viewing 42% Appearance Coating free of defects One way radar attenuation 76-77 GHz <2 dB Humidity Ageing (40° C., 95% RH, 500 hrs) Pass Thermal Shock Pass Thermal Cycle Pass Cold Temperature ageing Pass High Temperature ageing (80° C., 500 hrs) Pass

Example 3—Decorative Layer Comprising Multiple Layers

Substrate Preparation and Hard-Coating

[0222] An injection moulded polycarbonate substrate was prepared as describe above for Example 1. A hard-coat was provided by first priming the first surface by spray coating with PR6600 (SDC Technologies). After 10 minutes of evaporation, the primed first surface was subsequently spray coated with MP101 (SDC Technologies) to form a hard-coat.

[0223] The hard-coated substrate was then moved to a curing oven for 60 minutes at 130° C.

[0224] Subsequent coatings are performed within a 48 hour period so as to avoid ageing/contamination of the parts surfaces.

[0225] The substrate was blown down with deionised air and then loaded into a batch type vacuum chamber, which consists of a single coating chamber in which the samples are placed, evacuated and coated on the second surface directly onto the PC. Areas on the second surface are selectively masked to ensure no coating is applied.

Second Surface Reflective Layer

[0226] The hard-coated substrate was prepared for coating with a reflective layer as described for Example 1. A decorative layer including a reflective layer was deposited using the following conditions:

1.SUP.st .PVD Layer

[0227] Dual rotatable Target: Silicon (99.9 wt %) [0228] Argon @ 160 sccm [0229] Oxygen @ 302 sccm [0230] Pressure=2 e.sup.−3 mbar [0231] Power @ 35 kW @ 27 kHz [0232] Target to substrate distance=110 mm [0233] Deposition time=4 minutes [0234] Thickness=250 nm

2.SUP.nd .PVD Layer

[0235] 2nd PVD layer—reflective—Target: Aluminium/Germanium (50% wt) [0236] Argon @ 400 sccm [0237] Pressure=2.2 e.sup.−3 mbar [0238] Power @ 30 kW [0239] Target to substrate distance=110 mm [0240] Deposition time=10 minutes [0241] Thickness=70 nm

3.SUP.rd .PVD Layer

[0242] Dual rotatable Target: Silicon (99.9 wt %) [0243] Argon @ 96 sccm [0244] Oxygen @ 202 sccm [0245] Pressure=2 e-3 mbar [0246] Power @ 21 kW [0247] Target to substrate distance=110 mm [0248] Deposition time=1 minutes [0249] Thickness=20 nm

Overmolding of the Substrate

[0250] The second surface of the substrate, having a provided reflective layer, was prepared for overmolding with a second radio-transmissive polymer to provide an overmolded layer, using the protocol detailed at Example 1 and an oven temperature of 75° C.

[0251] The heated substrate was then loaded into the second-shot injection mould tool. An overmolded layer was provided by a second shot injection of opaque acrylonitrile-(ethylene-propylene-diene)-styrene (AEPDS) onto the second surface of the substrate, at a barrel temperature of 220° C. This overmolded layer covered the reflective layer on the substrate and the uncoated second surface of the substrate, thereby encapsulating the coating, to provide the decorative radome.

Assessment of the Radome

[0252] Environmental and Visual performance of the radome was assessed using the techniques described above, with the following result:

TABLE-US-00004 TABLE 4 Results Description Result Photopic reflectivity 2.sup.nd surface viewing 49% Appearance Coating free of defects One way radar attenuation 76-77 gHz <2 dB Humidity Ageing (40° C., 95% RH, 500 hrs) Pass Thermal Shock Pass Thermal Cycle Pass Cold Temperature ageing Pass High Temperature ageing (80° C., 500 hrs) Pass

Example 4—Reflective Coating of Indium (No Second Surface Hard-Coating)

Substrate Preparation and Hard-Coating

[0253] An injection moulded polycarbonate substrate was prepared and provided with a first surface hard-coat as describe above in Example 1.

Second Surface Reflective Layer

[0254] The hard-coated substrate was prepared for coating with a reflective layer as described above. The reflective layer was deposited using the following conditions: [0255] Reflective layer—Target: Indium (99.9 wt %) [0256] Argon @ 20 sccm [0257] Pressure=3.6 e-3 mbar [0258] Power @ 400 W [0259] Target to substrate distance=110 mm [0260] Deposition time=3.5 minutes [0261] Thickness=54 nm

Overmolding of the Substrate

[0262] The substrate, having a provided reflective layer, was prepared for overmolding with a second radio-transmissive polymer to provide an overmolded layer, using the protocol detailed at Example 1, above.

[0263] The heated substrate was then loaded into the second-shot injection mould tool. An overmolded layer was provided by a second shot injection of opaque Acrylonitrile Ethylene Styrene (AES) onto the second surface of the substrate, at a barrel temperature of 225° C. This overmolded layer covered the reflective layer on the substrate and the uncoated second surface of the substrate, thereby encapsulating the coating, to provide the decorative radome.

Assessment of the Radome

[0264] Environmental and Visual performance of the radome was assessed using the techniques described above, with the following result:

TABLE-US-00005 TABLE 5 Results Description Result Photopic reflectivity 2.sup.nd surface viewing 55% Appearance Fail - Coating visually crazed One way radar attenuation 76-77 gHz <2 dB

Example 5—Reflective Coating Across the Entirety of the Second Surface

Substrate Preparation and Hard-Coating

[0265] A polycarbonate substrate was prepared, cleaned and hard-coat was applied as described above at Example 1.

Second Surface Reflective Layer

[0266] A reflective layer was provided to the second surface as described at Example 1 above, with the exception that the second surface was not masked and the reflective layer was applied to the entirety of the second surface of the substrate.

Overmolding of the Substrate

[0267] The reflective layer covering the second surface of the substrate was overmolded in the manner described at Example 1.

Assessment of the Radome

[0268] The radome was not assessed for environmental and visual performance as the overmolded layer failed to adhere to the reflective coated substrate.

[0269] This failure indicates the need for an adhesion bond between the substrate and the overmolded layer. Consequently, the radome of the present invention does not need the provision of adhesives to bind the substrate to a second layer.

Example 6—Aluminium/Germanium Reflective Layer on a Second Surface Coating

Substrate Preparation and Hard-Coating

[0270] A polycarbonate substrate was prepared, cleaned and a hard-coat was applied as described above at Example 2. Consequently, the first surface of the substrate was provided with a hard-coat and unmasked portions of the second surface of the substrate were provided with a hard-coat. These unmasked portions include areas designed for deposition of the reflective layer.

Second Surface Reflective Layer

[0271] A reflective layer was provided to the second surface as described at Example 1 above.

Overmolding of the Substrate

[0272] The second surface of the substrate, having a provided reflective layer, was overmolded with a second radio-transmissive polymer to provide an overmolded layer, using the protocol detailed at Example 2, above.

Assessment of the Radome

[0273] Environmental and Visual performance of the radome was assessed using the techniques described above, with the following result:

TABLE-US-00006 TABLE 6 Results Description Result Initial appearance No defects One way radar attenuation 76-77 GHz <2 dB Dry Heat 115 C. Pass High temperature ageing 1000 hr @ 80° C. Pass Humidity Ageing (40° C., 95% RH, 1000 hr) Pass constant climate test Pass 240 hrs @ 40 C., 100RH Water immersion (240 hr @ 60° C.) Pass Thermal shock Pass Thermal cycle Pass cold temperature ageing Pass water boil 3 hrs 100 C. Pass

Example 7—Indium Reflective Layer on a Second Surface Coating

[0274] A polycarbonate substrate was prepared, cleaned and a hard-coat was applied as described above at Example 2. Consequently, the first surface of the substrate was provided with a hard-coat and unmasked portions of the second surface of the substrate were provided with a hard-coat. These unmasked portions include areas designed for deposition of the reflective layer.

Second Surface Reflective Layer

[0275] The hard-coated substrate was prepared for coating with an indium reflective layer as described at Example 4 above.

Overmolding of the Substrate

[0276] The second surface of the substrate, having a provided reflective layer, was overmolded with a second radio-transmissive polymer to provide an overmolded layer, using the protocol detailed at Example 2 above

Assessment of the Radome

[0277] Environmental and Visual performance of the radome was assessed using the techniques described above, with the following result:

TABLE-US-00007 TABLE 7 Results Description Result Photopic reflectivity 2.sup.nd surface viewing 50% Initial appearance No defects One way radar attenuation 76-77 gHz <2 dB Dry Heat 115 C. Pass High temperature ageing 1000 hr @ 80° C. Pass Humidity Ageing (40° C., 95% RH, 1000 hr) Pass constant climate test Pass 240 hrs @ 40 C., 100RH Water immersion (240 hr @ 60° C.) Pass Thermal shock Pass Thermal cycle Pass cold temperature ageing Pass water boil 3 hrs 100 C. Pass

[0278] Notably, the results of this Example compared to Example 4 indicates that indium can be used as a reflective layer if a second surface reflective coating is provided on portions of the substrate immediately below the applied indium coating.

Example 8—Tin Reflective Layer on a Second Surface Coating

[0279] A polycarbonate substrate was prepared, cleaned and a hard-coat was applied as described above at Example 2. Consequently, the first surface of the substrate was provided with a hard-coat and unmasked portions of the second surface of the substrate were provided with a hard-coat. These unmasked portions include areas designed for deposition of the reflective layer.

Second Surface Reflective Layer

[0280] The hard-coated substrate was prepared for coating with a reflective layer as described at Example 1 above. The reflective layer of tin was deposited using the following conditions: [0281] Reflective layer—Target: Tin (99.9 wt %) [0282] Argon @ 20 sccm [0283] Pressure=3.5 e-3 mbar [0284] Power @ 400 W [0285] Target to substrate distance=110 mm [0286] Deposition time=3.5 minutes [0287] Thickness=65 nm

Overmolding of the Substrate

[0288] The second surface of the substrate, having a provided reflective layer, was overmolded with a second radio-transmissive polymer to provide an overmolded layer, using the protocol detailed at Example 2, above.

Assessment of the Radome

[0289] Environmental and Visual performance of the radome was assessed using the techniques described above, with the following result:

TABLE-US-00008 TABLE 8 Results Description Result Photopic reflectivity 2.sup.nd surface viewing 57% Initial appearance No defects One way radar attenuation 76-77 gHz <2 dB Dry Heat 115 C. Pass High temperature ageing 500 hr @ 80° C. Pass Humidity Ageing (40° C., 95% RH, 500 hr) Pass Photopic reflectivity 2.sup.rd surface viewing: Pass 240 hrs @ 40 C., 100RH Water immersion (240 hr @ 60° C.) Pass Thermal shock Pass Thermal cycle Pass cold temperature ageing Pass water boil 3 hrs 100 C. Pass

[0290] Examples 6 to 8 demonstrate that a multi-layer overmolded radome can be formed including reflective layers formed of post-transition metals such as Indium and Tin, in addition to a metalloid alloys comprising Germanium, in the presence of a second surface hard-coat on the substrate. This is compared to Example 4 where Indium directly applied to the second surface of the substrate (without an interfacing hard-coat) crazed when the second shot was overmolded.

[0291] Without wanting to be bound by theory, the second surface hard-coat likely improves binding of the Tin and Indium layer to the substrate and helps control the residual stress of the deposited reflective layer during the thermal expansion caused by the second-shot overmolding. This consequently prevents crazing of the reflective layer as the substrate and reflective layer are heated during overmolding.

[0292] All methods described herein can be performed in any suitable order unless indicated otherwise herein or clearly contradicted by context. The use of any and all examples, or exemplary language (e.g., “such as”) provided herein, is intended merely to better illuminate the example embodiments and does not intrinsically pose a limitation on the scope of the claimed invention. However, such embodiments may be the subject of a claimed limitation, or may be considered as an additional feature in the event that it is included in a claim. No language in the specification should be construed as indicating any non-claimed element as essential.

[0293] The description provided herein is in relation to several embodiments which may share common characteristics and features. It is to be understood that one or more features of one embodiment may be combinable with one or more features of the other embodiments. In addition, a single feature or combination of features of the embodiments may constitute additional embodiments.

[0294] The subject headings used herein are included only for the ease of reference of the reader and should not be used to limit the subject matter found throughout the disclosure or the claims. The subject headings should not be used in construing the scope of the claims or the claim limitations.

[0295] Those skilled in the art will appreciate that the invention described herein is susceptible to variations and modifications other than those specifically described. It is to be understood that the invention includes all such variations and modifications. The invention also includes all of the steps, features and/or functions referred to, or indicated in this specification, individually or collectively, and any and all combinations of any two or more of the steps or features.

[0296] Throughout this specification, unless the context requires otherwise, the word “comprise”, or variations such as “comprises” or “comprising”, will be understood to imply the inclusion of a stated element or integer or group of elements or integers but not the exclusion of any other element or integer or group of elements or integers.

[0297] Also, it is to be noted that, as used herein, the singular forms “a”, “an” and “the” include plural aspects unless the context already dictates otherwise.

[0298] Future patent applications may be filed in Australia or overseas on the basis of or claiming priority from the present application. It is to be understood that the following provisional claims are provided by way of example only, and are not intended to limit the scope of what may be claimed in any such future applications. Also, features may be added to or omitted from the provisional claims at a later date so as to further define or re-define the invention or inventions.