WO2014174310A1

WO2014174310A1 - Laminated glazing

Info

Publication number: WO2014174310A1
Application number: PCT/GB2014/051298
Authority: WO
Inventors: Jonathan Barclay Dixon
Original assignee: Pilkington Group Limited
Priority date: 2013-04-25
Filing date: 2014-04-25
Publication date: 2014-10-30
Also published as: GB201307496D0

Abstract

A laminated glazing comprising first and second panes of glazing material joined by an interlayer structure is described. There is an obscuration band on the first glazing pane extending around at least a portion of the periphery thereof. The interlayer structure comprises a first adhesive layer having a thickness of between 6μm and 100μm, a carrier ply having an infra red reflecting coating on a surface thereof, a second adhesive layer thicker than the first adhesive layer and a film comprising an electrically actuated layer. The first adhesive layer contacts a portion of the surface of the first pane of glazing material and a portion of the obscuration band. The film is either (i) between the second adhesive layer and the carrier plyor (ii) between the second adhesive layer and the second pane of glazing material. The infra red reflecting coating is between the first and second adhesive layers and the second adhesive layer is in contact with the second pane of glazing material.

Description

LAMINATED GLAZING

The present invention relates to a laminated glazing comprising an electrically actuated layer and an infra red reflecting coating on a plastic ply, in particular a sunroof for a vehicle comprising a suspended particle device film and an infra red reflecting coating on a plastic ply laminated between two panes of glazing material.

Films are known having an electrically actuated layer where the optical properties of the electrically actuated layer are changeable upon applying an electric field across the layer. Examples are liquid crystal display (LCD) films and suspended particle device (SPD) films A suspended particle device (SPD) film, such as that described in WO2005/102688 A2 is a film comprising a plurality of particles suspended within a liquid suspension medium, which are held within a polymer medium. The film is switchable between an opaque state (when no is voltage applied), and a transparent state (when voltage is applied). The degree of relative alignment between the particles is determined by the applied AC voltage, such that an SPD-based device exhibits a variable optical transmission when a variable voltage is applied. It is known to produce a laminated glass having an SPD film in between two plies of glass and various constructions have been proposed.

In one laminated glazing construction the SPD film is placed between two plies of bonding interlayer, the two plies of bonding interlayer being in between two plies of glazing material. Another option is to place the SPD film in a cut out region in a first ply of interlayer material to "frame" the SPD film. The framed SPD film can then be placed between two plies of interlayer material, and laminated between two plies of glazing material. This construction is described in WO2007/122428A1.

It is known that SPD films are sensitive to heat and it has been proposed to reduce the amount of heat incident on an SPD film in a laminated glazing by incorporating an infra red (IR) reflecting film (often referred to as an infra red reflective film) in between the SPD film and the heat source, i.e. the sun. The IR reflecting film may be an IR reflecting coating deposited on one of the surfaces of the outer facing pane of glazing material of the laminate, or may be an IR reflecting coating carried on a ply in between the outer facing pane of glazing material of the laminate and the SPD film. The IR reflecting film may be carried on an interlayer ply or an additional plastic ply or film.

IR reflecting films comprising an IR reflecting coating on a plastic carrier ply are known in the art, and typically comprise a polyethylene terephthalate (PET) film having a vacuum deposited infra red reflecting coating thereon. A laminated glazing comprising an SPD film and an IR reflecting film is described in WO2007/122426A1.

There are however problems when incorporating an IR reflecting coating deposited on a plastic carrier ply into a laminated glazing and it is known that the incorporation of an IR reflecting coating deposited on a plastic carrier ply into a laminated glazing can cause a problem of optical distortion, particularly in reflection. In the art this optical distortion has been referred to as "orange peel" or "apple sauce". In WO97/03763A1 the problem of optical distortion is described as being due to commercial sheet polyvinyl butyral (PVB) being textured for de-airing during lamination. The texture from the PVB will emboss onto the PET (the PET sheet being a carrier for an IR reflecting coating). Subsequently, the reflective image from the vapour deposited coating (on the PET) is not planar and is objectionable.

When incorporating an SPD film into a laminated glazing including a PET ply having an IR reflecting coating thereon, the problem of optical distortion is increased when the SPD film is in the darkened state because the optical distortion is more visually apparent.

It has been proposed to overcome the problem of optical distortion from laminated glass structures which include an IR reflecting coated plastic intermediate layer by using a thin adhesive layer instead of the conventional thickness of such bonding interlayer, i.e. 0.38mm - 0.76mm. In WO97/03763A1 it is taught that for glass sheets having smooth surfaces the aforementioned problem of optical distortion can be eliminated by using a layer of adhesive having a thickness below 127μπι, in particular having a thickness of between 13μπι and 76μπι. The examples in WO97/03763A1 are of flat glass and not curved glass.

US 5,932,329 describes a laminated glass pane comprising two glass sheets and a transparent support film having an infra red reflecting surface coating connected to the two glass sheets by adhesive layers, the first adhesive layer having a thickness of at most 50μπι and the second adhesive layer has a thickness of 0.76mm. There is no disclosure in

US 5,932,329 of the glass sheets having anything on any of the surfaces thereof that would lead a person skilled in the art to understand that the glass sheets had anything other than a smooth surface.

However when manufacturing a commercial laminated glazing, in particular for use in a vehicle, it is conventional to include an obscuration band of opaque ceramic ink extending around the entire periphery of at least one of the major surfaces of the glazing. For example when the laminated glazing is a vehicle windshield it is known in the art that the obscuration band serves to improve the appearance of the windshield by masking the interface between the glazing and the vehicle and also to shield adhesive fixing the windshield in the aperture in the vehicle bodywork from ultra violet which might damage the integrity thereof over time. The obscuration band also serves to hide electrical connectors or the like so that such electrical connectors are not observable when the laminated glazing is in use. Commonly the obscuration band comprises a solid coloured band extending around the periphery of the panel and a fade out band extending inwardly from the inner edge of the solid coloured band where the obscuration is applied in a decorative pattern with anything from 1% to 99% of the surface area of the glass being obscured. The fade out band avoids the appearance of an abrupt edge and the gradual decrease in opacity is more visually acceptable.

When manufacturing a laminated glazing comprising two panes of glass joined by a sheet or ply of PVB interlay er material, the obscuration band is applied (by printing, painting etc) to the appropriate glass surface when the glass pane is cold (typically at ambient temperature) and is fired onto that surface by raising the temperature of the glass pane such that the obscuration band forms an intimate bond to the glass surface. The thickness of the obscuration band when fired onto the glass surface is typically between 5μπι and 50μπι.

The consequence of having an obscuration band is that the major surface of the pane of glass is no longer smooth across the entire surface of the pane i.e. in the region of the obscuration band, and in particular in the region of the fade out band.

In order to apply the teaching in WO97/03763A1, it would be possible to have the obscuration band on both exposed surfaces of the outer panes of the laminated glazing such that surfaces of the outermost panes facing the laminating layers are smooth. This is illustrated in figure 1.

Figure 1 shows (not to scale) a laminated glazing 100 having a first glass pane 102 joined to a second glass pane 104 via an interlay er structure.

With reference to the orientation of the glazing 100 shown in figure 1, the first glass pane 102 has an upper surface and a lower surface. On the upper surface these is an obscuration band 103 and a fade out band 105. The obscuration band and fade out band extend around the periphery of the upper surface of the first glass pane 102.

A first adhesive layer 106 is in contact with the lower surface of the first glass pane 102, which is a smooth surface because there is no obscuration band or fade out band thereon. This first adhesive layer 106 has a thickness between 6μπι and ΙΟΟμπι. In contact with the first adhesive layer 106 is an IR reflecting coating 107 that is being carried on a plastic ply 108. The plastic ply 108 is ΙΟΟμπι thick. The first adhesive layer 106, the IR reflecting coating 107 and the plastic ply 108 are coextensive with each other. The first adhesive layer 106, the IR reflecting coating 107 and the plastic ply 108 form a composite ply 101 i.e. prior to being incorporated into the laminated glazing the first adhesive layer 106, the IR reflecting coating 107 and the plastic ply 108 are joined together as composite ply 101. It is possible for the positions of the plastic ply 108 and the IR reflecting coating 107 to be reversed. The composite ply 101 may be made in accordance with WO97/03763A1.

In contact with the plastic ply 108 is a second adhesive layer 109 that is between

0.38mm and 0.76mm thick. In contact with the second adhesive layer is the upper surface of second glass pane 104. On the lower surface of the second glass pane is an obscuration band 103' and a fade out band 105'. The first glass pane 102 is joined to the second glass pane 104 via an interlay er structure consisting of the first adhesive layer 106, the IR reflecting coating 107, the plastic ply 108, and the second adhesive layer 109.

Even though the laminated glazing 100 comprises an obscuration band and a fade out band, it is possible to apply the teaching of WO97/03763A1 using the construction shown in figure 1.

Another alternative way to practice the teaching of WO97/03763A1 would be to ensure the thin adhesive layer only extended between the obscuration band with the edge of the thin adhesive layer being offset from the periphery of the obscuration band such that there was no contact between the thin adhesive layer and the obscuration band or fade out band. This is illustrated in figures 2 and 3.

Figure 2 shows (not to scale) a laminated glazing 110 having a first glass pane 112 joined to a second glass pane 114 via an interlayer structure.

With reference to the orientation of the glazing 110 shown in figure 2, the first glass pane 112 has an upper surface and a lower surface. On the lower surface of the first glass pane 112 there is an obscuration band 113 and a fade out band 115. The obscuration band and fade out band extend around the periphery of the lower surface of the first glass pane 112. Consequently the entire lower surface of the first glass pane 112 is not smooth.

A first adhesive layer 116 is in contact with the lower surface of the first glass pane 112 only in between the edges of the fade out band 115 such that the first adhesive layer 116 does not contact the fade out band 115 i.e. there is a space between the edge of the fade out band and the peripheral edge of the first adhesive layer 116.

The first adhesive layer 116 has a thickness between 6μπι and ΙΟΟμπι. In contact with the first adhesive layer is an IR reflecting coating 117 that is being carried on a plastic ply 118. The plastic ply 118 is ΙΟΟμπι thick. The first adhesive layer 116, the IR reflecting coating 117 and the plastic ply 118 are coextensive with each other. The first adhesive layer 116, the IR reflecting coating 117 and the plastic ply 118 are a composite ply 111 (the reference numeral 111 is not indicated on the figure for clarity) i.e. prior to being incorporated into the laminated glazing the first adhesive layer 116, the IR reflecting coating 117 and the plastic ply 118 are joined together as composite ply 111. It is possible for the positions of the plastic ply 118 and the IR reflecting coating 117 to be reversed. . The composite ply 111 may be made in accordance with WO97/03763A1.

In contact with the plastic ply 118 is a second adhesive layer 119. Since the composite ply only extends between, and is slightly offset from, the edges of the fade out band the second adhesive layer 119 also contacts the fade out band 115 and the obscuration band 113. The second adhesive layer 119 also contacts a portion of the lower surface of the first glass pane 112 in the region of the fade out band that is not covered with ink. The second adhesive layer 119 has a thickness between 0.38mm and 0.76mm.

Also in contact with the second adhesive layer 119 is the upper surface of a second glass pane 114. On the lower surface of the second glass pane is an obscuration band 113' and a fade out band 115'. The first glass pane 112 is joined to the second glass pane 114 via an interlay er structure consisting of the first adhesive layer 116, the IR reflecting coating 117, the plastic ply 118, and the second adhesive layer 119.

Even though the laminated glazing 110 comprises an obscuration band and a fade out band, it is possible to apply the teaching of WO97/03763A1 using the construction shown in figure 2.

Figure 3 shows (not to scale) a laminated glazing 120 having a first glass pane 122 joined to a second glass pane 124 via an interlayer structure.

With reference to the orientation of the glazing 120 shown in figure 3, the first glass pane 122 has an upper surface and a lower surface. On the lower surface there is an obscuration band 123 that extends around the periphery of the lower surface of the first glass pane 122. Consequently the entire lower surface of the first glass pane is not smooth. A first adhesive layer 126 is in contact with the lower surface of the first glass pane 122 only in between the edges of the obscuration out band 123 such that the first adhesive layer does not contact the obscuration band 123. The first adhesive layer 126 has a thickness between 6μπι and ΙΟΟμπι.

In contact with the first adhesive layer 126 is an IR reflecting coating 127 that is being carried on a plastic ply 128. The plastic ply 128 is ΙΟΟμπι thick. The first adhesive layer 126, the IR reflecting coating 127 and the plastic ply 128 are coextensive with each other. The first adhesive layer 126, the IR reflecting coating 127 and the plastic ply 128 are a composite ply 121 (reference numeral 121 is not indicated on the figure for clarity) i.e. prior to being incorporated into the laminated glazing the first adhesive layer 126, the IR reflecting coating 127 and the plastic ply 128 are joined together as a composite ply 121 (which is the same as composite ply 111). It is possible for the positions of the plastic ply 128 and the IR reflecting coating 127 to be reversed. The composite ply 121 may be made in accordance with

WO97/03763A1.

In contact with the plastic ply 128 is a second adhesive layer 129. Since the composite ply 121 only extends between the edges of the obscuration band and does not contact the obscuration band 123, the second adhesive layer 129 also contacts the obscuration band 123. The second adhesive layer has a thickness between 0.38mm and 0.76mm.

In contact with the lower surface of the second adhesive layer 129 is an SPD film 131.

The SPD film 131 is sandwiched between the second adhesive layer 129 and a third adhesive layer 130 i.e. the upper surface of the third adhesive layer 130 is in contact with the lower surface of the SPD film 131. The third adhesive layer has a thickness between 0.38mm and 0.76mm.

The SPD film 131 is sized to be coextensive with the second adhesive layer 129 and third adhesive layer 130. Consequently the periphery of the SPD film is beneath the obscuration band 123 which provides protection from sunlight. The edge of the SPD film may be slightly inboard of the peripheral edge of the laminated glazing with the edge of the SPD film being obscured by the obscuration band when the laminated glazing is viewed normal to the upper surface of the first glass pane 122.

The lower surface of the third adhesive layer 130 is in contact with the upper surface of a second glass pane 124. The lower surface of the second glass pane has an obscuration band 123' thereon extending around the periphery thereof. The first glass pane 122 is joined to the second glass pane 124 via an interlayer structure consisting of the first adhesive layer 126, the IR reflecting coating 127, the plastic ply 128, the second adhesive layer 129, the SPD film 131 and the third adhesive layer 130.

Even though the laminated glazing comprises an obscuration band, it is possible to apply the teaching of WO97/03763A1 using the construction shown in figure 3.

Surprisingly the present inventor has found that it possible to produce a laminated glazing having a thin layer of adhesive on a surface of a pane of glazing material that is not smooth.

Accordingly from a first aspect the present invention provides a laminated glazing comprising a first pane of glazing material and a second pane of glazing material, the first pane of glazing material having a first major surface and an opposing second major surface, there being an obscuration band on the second major surface extending around at least a portion of the periphery of the first pane of glazing material such that the second major surface is not smooth, the first pane of glazing material being joined to the second pane of glazing material by an interlayer structure comprising a first adhesive layer having a thickness of between 6μπι and ΙΟΟμπι, a carrier ply having an infra red reflecting coating on a surface thereof, a second adhesive layer thicker than the first adhesive layer and a film comprising an electrically actuated layer, wherein the first adhesive layer is between the first pane of glazing material and the carrier ply and the first adhesive layer contacts a portion of the second major surface of the first pane of glazing material and a portion of the obscuration band; the carrier ply is between the first adhesive layer and the film; the film is either (i) between the second adhesive layer and the carrier ply or (ii) between the second adhesive layer and the second pane of glazing material; the infra red reflecting coating is between the first adhesive layer and the second adhesive layer; the first adhesive layer and the second adhesive layer are between the first pane of glazing material and the second pane of glazing material; and the second adhesive layer is in contact with the second pane of glazing material.

In embodiment (ii) the film may be attached to the second pane of glazing material by the second adhesive layer extending beyond the edges of the film, or by the laminated glazing comprising one or more additional adhesive layers between the film and second pane of glazing material.

Surprisingly even though the obscuration band is raised with respect to the second major surface of the first pane of glazing material such that the entire second major surface of the first pane of glazing material is no longer smooth, the thin adhesive layer is still able to adhere thereto to form a laminate of acceptable quality, in particular in the region of the obscuration band.

A laminated glazing according to the first aspect of the present invention passed all relevant impact and safety tests and could be interchanged for an equivalent laminated glazing where instead of the first adhesive layer having a thickness between 6μπι and ΙΟΟμπι the first adhesive layer had a thickness between 0.38mm and 0.76mm.

Preferably the electrically actuated layer has a high visible light transmission state and a low visible light transmission state.

For the avoidance of doubt, there may be other layers of material in between the second adhesive layer and the infra red reflecting coating.

Preferably the first adhesive layer has a thickness between ΙΟμπι and ΙΟΟμπι, more preferably between 13μπι and 76μπι. Preferably the thickness of the obscuration band is between Ιμιη and 150μιη.

Preferably the thickness of the obscuration band is between Ιμιη and ΙΟΟμιη, more preferably between Ιμπι and 50μιη, even more preferably between Ιμπι and 25μιη, most preferably between 5μιη and 25μιη.

Preferably the thickness of the obscuration band is between 5μιη and ΙΟΟμιη, more preferably between 5μιη and 50μιη.

In some embodiments preferably the obscuration band comprises a fade out band and the first adhesive layer contacts at least a portion of the fade out band. Over the fade out band the surface presented to the first adhesive layer is not smooth.

Preferably the fade out band is a pattern such that between 1% and 99% of the surface area of at least a portion of the second major surface of the first pane of glazing material is obscured by the fade out band. Preferably the fade out band comprises a plurality of disconnected optically opaque regions. Preferably the disconnected regions of the fade out band have a size distribution such that smaller sized regions are located closer towards the geometric centre of the second major surface of the first pane of glazing material.

Preferably the fade out band has a width of between 0.25cm and 10 cm, preferably between 0.5cm and 5cm.

Preferably the thickness of the fade out band is between Ιμπι and 150μπι

Preferably the thickness of the fade out band is between Ιμπι and ΙΟΟμπι, more preferably between Ιμπι and 50μπι, even more preferably between Ιμπι and 25μπι, most preferably between 5μπι and 25μπι.

Preferably the thickness of the fade out band is between 5μπι and ΙΟΟμπι, more preferably between 5μπι and 50μπι.

It has been found that an acceptable laminating glazing is still able to be produced when the obscuration band comprises a fade out band. A laminated glazing according to this embodiment passed all relevant impact and safety tests and could be interchanged for an equivalent laminated glazing where instead of the first adhesive layer having a thickness of between 6μπι and ΙΟΟμπι the first adhesive layer had a thickness of between 0.38mm and 0.76mm.

For a laminated glazing according to the first aspect of the present invention, the second pane of glazing material has a first major surface and an opposing second major surface. Preferably there is an obscuration band on the first and/or second major surface extending around a portion of the periphery of the second pane. Preferably the obscuration band on the second pane of glazing material is in contact with the second adhesive layer. Preferably the obscuration band on the second pane of glazing material comprises a fade out band.

In some embodiments the visible light transmission calculated according to

BS EN410 through a portion of the laminated glazing not covered with the obscuration band is at least 70%.

In some embodiments the visible light transmission calculated according to

BS EN410 through a portion of the laminated glazing not covered with the obscuration band is less than 70%, preferably less than 50%, more preferably less than 10%, most preferably less than 5%.

In some embodiments the visible light transmission calculated according to BS EN410 through a portion of the laminated glazing not covered with the obscuration band and without the electrically actuated layer is less than 70%, preferably less than 50%, more preferably less than 10%, most preferably less than 5%.

Embodiments of the first aspect of the present invention have other preferable features.

Preferably the thickness of the first pane of glazing material is between 1mm and 4mm, more preferably between 1.6mm and 3.1mm, most preferably between 1.8mm and 2.2mm.

Preferably the thickness of the second pane of glazing material is between 1mm and 4mm, more preferably between 1.6mm and 3.1mm, most preferably between 1.8mm and 2.2mm.

Preferably the film comprising the electrically actuated layer comprises an SPD film or an LCD film.

Preferably the film comprising the electrically actuated layer is an SPD film or an LCD film.

Preferably the second adhesive layer has a thickness between 0.1mm and 2mm, more preferably between 0.1mm and 1mm, even more preferably between 0.2mm and 0.8mm.

Preferably interlayer structure comprises a third adhesive layer, wherein the film comprising the electrically actuated layer is between the second adhesive layer and the third adhesive layer.

Preferably the film comprising the electrically actuated layer is located in a cut out region in an adhesive layer configured as a frame, and the adhesive layer configured as a frame is between the second adhesive layer and the carrier ply. Preferably the film comprising the electrically actuated layer is located in a cut out region in a fourth adhesive layer, and the fourth adhesive layer is between the second adhesive layer and a third adhesive layer.

Preferably at least a portion of an edge of the film comprising the electrically actuated layer is in registration with the obscuration band.

To protect the film comprising the electrically actuated layer from the effects of sunlight, the film is positioned in between the infra red reflecting coating and the second pane of glazing material, with the first pane of glazing material configured in use to face the sun.

Preferably the film is coextensive with infra red reflecting coating.

Preferably one or more edges of the film lie within the perimeter defined by the periphery of the infra red reflecting coating.

Preferably the entire perimeter of the film lies within the perimeter defined by the periphery of the infra red reflecting coating.

Preferably the film is coextensive with carrier ply.

Suitably one or more edges of the film lie within the perimeter defined by the periphery of the carrier ply.

Suitably the entire perimeter of the film lies within the perimeter defined by the periphery of the carrier ply.

Preferably the laminated glazing has a convex surface and an opposite concave surface.

Preferably the laminated glazing is curved in at least one direction. Preferably the radius of curvature in the at least one direction is between 500mm and 20000mm, more preferably between 1000mm and 8000mm.

Preferably the carrier ply is a plastic ply. Preferably the carrier ply is polyester or polycarbonate. Preferably the polyester is polyethylene terephthalate (PET).

Preferably the carrier ply has a thickness between 0.01mm and 0.5mm, more preferably between 0.01mm and 0.25mm, most preferably between 0.01mm and 0.1mm.

Preferably the infra red reflecting coating includes one or more metallic layers (or metal oxide layers) and one or more dielectric layers, typically forming a multilayer stack. The multilayer stack structure may be repeated to enhance the reflectivity of the film. Amongst other similar metals, silver, gold, copper, nickel and chromium may be used as the metallic layer in a multilayer stack; indium oxide, antimony oxide or the like may be used as the metal oxide layer. Films comprising one or two layers of silver interleaved between layers of a dielectric such as an oxide of silicon, aluminium, titanium, vanadium, tin or zinc are typical multilayer stacks. Generally the one or more layers from which the infrared reflective coating is formed have a thickness of the order of tens of nanometres.

As an alternative to the (metal/dielectric) based coating described above, the coating may include a plurality of non-metallic layers, such that it functions as a band filter (the band being focussed on the near infrared region of the electromagnetic spectrum).

Preferably the obscuration band extends from the periphery of the first pane of glazing material to less than 30cm from the periphery of the first pane of glazing material, more preferably to less than 20cm from the periphery of the first pane of glazing material.

Preferably the obscuration extends around the entire periphery of the first pane of glazing material.

Preferably the obscuration band comprises a first portion and a second portion, wherein the first portion extends closer to the geometric centre of the second major surface than the second portion.

Preferably the first pane of glazing material has a coating on a portion of a major surface thereof, such that the obscuration band and/or when present the fade out band, is on the coating.

Preferably the first pane of glazing material is glass.

Preferably the first pane of glazing material and/or the second pane of glazing material is glass having a soda-lime-silica composition as defined in BS EN 572-1 and BS EN 572-2 (2004).

Preferably the first pane of glazing material and/or the second pane of glazing material comprises a laminated pane.

Preferably the thickness of the obscuration band is between 5μπι and 150μπι, more preferably between ΙΟμπι and 50μπι.

The obscuration band may not have uniform thickness and may vary in thickness.

Preferably the infra red reflective coating is in between the first adhesive layer and the carrier ply.

Preferably the carrier ply is in between the first adhesive layer and the infra red reflective coating.

Preferably the first adhesive layer comprises polyvinyl butyral (PVB).

Preferably first adhesive layer comprises a copolymer of ethylene, such as ethylene vinyl acetate (EVA).

Preferably first adhesive layer comprises polyurethane, in particular a thermoplastic polyurethane (TPU). Preferably the laminated glazing is a vehicle glazing.

Preferably the laminated glazing is a windscreen for a vehicle, a sunroof for a vehicle, a side window for a vehicle, a rear window for a vehicle, a pane of an insulated glazing unit, a window for a building or an interior partition for a building.

Preferably the second adhesive layer comprises polyvinyl butyral (PVB).

Preferably the second adhesive layer comprises a copolymer of ethylene, such as ethylene vinyl acetate (EVA).

Preferably the second adhesive layer comprises polyurethane, in particular a thermoplastic polyurethane (TPU).

Preferably the first adhesive layer and/or the second adhesive layer are tinted.

Preferably the second pane of glazing material has an obscuration band on a major surface thereof.

Preferably the second pane of glazing material has a coating on a portion of a major surface thereof.

Preferably the second pane of glazing material is glass.

The present invention also provides from a second aspect a method of making a laminated glazing comprising the steps: (i) providing a first pane of glazing material having a first major surface and an opposing second major surface; there being an obscuration band on a portion of the second major surface; (ii) positioning a composite ply onto the second major surface of the first pane of glazing material, the composite ply comprising a carrier ply having an infra red reflecting coating on at least a portion of a major surface thereof and a first layer of adhesive, the first layer of adhesive having a thickness between 6μπι and ΙΟΟμπι, the composite ply being positioned onto the second major surface of the first pane of glazing material such that the first layer of adhesive contacts the obscuration band; (iii) positioning a film comprising an electrically actuated layer on the composite ply; (iv) positioning a second adhesive layer on the composite ply such that either (a) the film is between the first adhesive layer and the second adhesive layer, or (b) that the second adhesive layer is between the film and the composite ply; (v) positioning a second ply of glazing material on the second adhesive layer; and (vi) applying suitably high temperature and pressure to laminate the first sheet of glazing material to the second pane of glazing material via the first adhesive layer and the second adhesive layer.

Preferably the first adhesive layer has a thickness between ΙΟμπι and ΙΟΟμπι, preferably between 13μπι and 76μπι. It is to be understood within the context of the present invention that when a layer A is positioned onto a layer B, this does not rule out the possibility of there being one or more other layers i.e. layers C, D, E etc in between layer A and layer B.

It is also to be understood that the adhesive layers used in the present invention are conveniently available in sheet form and such a sheet may be referred to as a ply. The layer of adhesive in sheet form prior to being incorporated in the laminated glazing is often referred to as an interlayer.

Preferably the second adhesive layer is between the film and the composite ply, and wherein before step (v) a third adhesive layer is positioned on the film such that the film is between the third adhesive layer and the second adhesive layer.

Preferably during step (iii) the film is positioned in a cut-out region in an adhesive layer configured to frame the film.

Preferably the film is positioned in a cut-out region in a fourth adhesive layer, and the fourth adhesive layer having the film therein is positioned on the composite ply.

When the laminated glazing comprises a third adhesive layer and a fourth adhesive layer having a cut-out region therein, preferably the method comprises the step of positioning the fourth adhesive layer having the film located in a cut-out region therein on the third layer, before the positioning of the second adhesive layer and before the second pane of glazing material is positioned on the second adhesive layer.

Preferably the film comprising the electrically actuated layer is an SPD film or an

LCD film.

The invention will now be described with reference to the following figures (not to scale) in which,

Figure 1 is a cross sectional view of a laminated glazing having an obscuration band and a fade out band, where there is a thin adhesive layer on a smooth surface;

Figure 2 is a cross sectional view of another laminated glazing having an obscuration band and a fade out band, where there is a thin adhesive layer on a smooth surface;

Figure 3 is a cross sectional view of another laminated glazing having an obscuration band and a fade out band, where there is a thin adhesive layer on a smooth surface;

Figure 4 is a schematic view of a laminated glazing to identify the surfaces thereof;

Figure 5 is a plan view of a laminated glazing having an obscuration band on surface 2 and surface 4;

Figure 6 is a schematic cross sectional view of the laminated glazing of figure 5;

Figure 7 shows in more detail a portion of an obscuration band and a fade out region; Figure 8 is a schematic cross sectional view of a laminated glazing according to an embodiment of the present invention;

Figure 9 is a schematic cross sectional view of a laminated glazing according to another embodiment of the present invention;

Figure 10 is a schematic cross sectional view of a laminated glazing according to another embodiment of the present invention;

Figure 11 is a plan view of another laminated glazing showing a different type of obscuration band and fade out band; and

Figure 12 is an exploded view of figure 10.

Figure 4 shows a conventional laminated glazing 10 consisting of two panes of glass

12, 14 joined by an adhesive layer in the form of a sheet of PVB 16. The first glass pane 12 has a first major surface 1 and an opposing second major surface 2. The second glass pane 14 has a first major surface 3 and an opposing second major surface 4. When installed in a vehicle or building, the major surface 1 faces towards the external environment (designated by the sun 9) and the major surface 4 faces the inside of the vehicle or building. Glass pane 12 is then the "outer pane" of the laminated glazing and glass pane 14 is the "inner pane" of the laminated glazing. The major surface 1 is referred to as "surface 1" or "SI" of the laminated glazing 10. The major surface 2 is referred to as "surface 2" or "S2" of the laminated glazing 10. The major surface 3 is referred to as "surface 3" or "S3" of the laminated glazing 10. The major surface 4 is referred to as "surface 4" or "S4" of the laminated glazing 10. As is conventional in the art, this nomenclature is used for the inner and outer panes of glazing material of a laminated pane, even when there is more than one ply of interlay er material in between the inner and outer panes.

Figure 5 shows a schematic plan view of a laminated glazing 20 having an obscuration band 23 with a fade out band 25 on "surface 2" (S2) and "surface 4" (S4) of the laminated glazing. A schematic cross section of the laminated glazing 20 is shown in figure 6. With reference to figures 5 and 6, the laminated glazing 20 comprises a first curved glass sheet 22 joined to a second curved glass sheet 24 by an adhesive interlayer 26 i.e. PVB, EVA or TPU. There is an obscuration band 23 and a fade out band 25 on "surface 2" (S2). There is also an obscuration band 23' and a fade out band 25' on "surface 4" (S4). Note that only "surface 1" (SI) and "surface 4" (S4) are labelled in figure 6.

In plan view, the laminated glazing 20 has a length 21a and a width 21b. The obscuration band 23 extends around the entire periphery of the glazing. The fade out band 25 extends around the entire periphery of the obscuration band. Along the length of the laminated glazing 20 the obscuration band has a width 27 and the fade out band has a width 29. Along the width of the laminated glazing 20 the obscuration band has a width 31 and the fade out band has a width 33.

Figure 7 shows a portion 23" of the obscuration band 23 and a portion 25" of the fade out band 25 of the laminated glazing 20. As can be seen from the figure, the portion 25" consists of a number of small dots decreasing in diameter as the distance from the periphery of the obscuration band increases. The edge of the fade out band is defined by the positions of the smallest dots. Other patterns are known in the art for the design of the fade out band.

Figure 8 shows a laminated glazing 141 in accordance with the first aspect of the present invention. Although in cross section the laminated glazing 141 is shown as being flat, it may be curved as is the case for the laminated glazing 20 shown in figure 6.

The laminated glazing 141 comprises a first pane of glass 142 and a second pane of glass 144 each 2.1mm thick. The first pane of glass 142 is joined to the second pane of glass 144 via an interlay er structure that will be described in more detail hereinafter.

In use, the first pane of glass is the outer pane of the laminated glazing, see figure 4 for the conventional naming of the surfaces. There is no obscuration band on "surface 1" (SI). On "surface 2" (S2) there is an obscuration band 143 and a fade out band 145 around the periphery of the pane 142. The obscuration band 143 and the fade out band 145 are each about 12μπι thick. In contact with the second major surface of the first pane of glass 142 is an adhesive layer of PVB 146 that is 20μπι thick. The layer of PVB 146 contacts the obscuration band 143 and the fade out band 145. The layer of PVB 46 also contacts the smooth glass surface of glass pane 142 inboard of the edge of the fade out band.

Joined to the adhesive layer of PVB 146 is an infra red reflecting film 151. The infra red reflecting film 151 consists of a ply of a carrier film of PET 152 having an infra red reflecting coating 153 on a surface thereof. In an alternative embodiment to that shown, the infra red reflecting film 151 is configured such that the positions of the ply of PET 152 and the infra red reflecting coating 153 are reversed. That is, either the ply of PET 152 or the infra red reflecting coating 153 contacts the adhesive layer 146. It is preferable to have the infra red reflecting coating 153 in between the adhesive ply of PVB 146 and the PET ply 152 (as shown in figure 8). Conveniently the first adhesive layer 146 and the infra red reflecting film 151 are joined prior to being incorporated in the laminated glazing, being a composite ply of the type described with reference to the figures 1, 2 and 3 and which may be made in accordance with WO97/03763A1.

The PET ply 152 is about ΙΟΟμιη thick. As shown in figure 8, joined to the PET ply 152 is another layer of PVB 154. The layer of PVB 154 is 0.76mm thick.

Joined to the layer of PVB 154 is an SPD film 155. The SPD film is between and in contact with the layer of PVB 154 and another layer of PVB 147. The layer of PVB 147 is 0.76mm thick.

The layer of PVB 147 is joined to the second pane of glass 144. On "surface 4" (S4) there is an obscuration band 143' and a fade out band 145'extending around the periphery of the pane 144.

It is evident from the above that the interlay er structure that joins the first pane 142 to the second pane 144 consists in contact sequence of the adhesive layer 146, the infra red reflecting coating 153, the PET ply 152, the adhesive layer 154, the SPD film 155 and the adhesive layer 147.

Although in figure 8 the SPD film 155 is shown as extending to the edge of the laminated glazing, it is preferable to have the SPD film inboard of the edge of the laminated glazing but positioned such that when viewed in cross-section (as in figure 8) the edges of the SPD film are below the obscuration band 143. It is advantageous for the entire peripheral edge of the SPD film to be beneath the infra red reflecting coating 153.

Figure 9 shows a laminated glazing 241 according to another embodiment of the first aspect of the present invention. The laminated glazing 241 has a first pane of glass 242 joined to a second pane of glass 244 via an interlayer structure that will be described in more detail hereinafter.

The first pane of glass is low iron float glass and has a thickness of 2.1mm. For clarity only "surface 1" (SI) and "surface 4" (S4) of the laminated glazing 241 are indicated on the figure but the other surfaces follow the naming convention described with reference to figure 4. Although the laminated glazing is shown as being flat in cross section, it may be curved as shown in figure 6.

An obscuration band 243 and a fade out band 245 are on the inner surface of the pane of glass 242 i.e. on "surface 2" (S2). The obscuration band 243 and the fade out band 245 are about 12μπι thick and extend around the periphery of the pane 242. An adhesive layer of PVB 246 that is 20μπι thick is in contact with the inner surface of the pane of glass 242 and also in contact with the obscuration band 243 and the fade out band 245. In contact with the adhesive layer of PVB 246 is an infra red reflecting coating 253. The infra red reflecting coating 253 is in contact with a PET ply 252 and is carried thereon. Prior to being

incorporated into the laminated glazing 242, the infra red reflecting coating 253 is part of a film 251 consisting of the infra red reflecting coating 253 on PET ply 252. It is preferred that prior to being incorporated into the laminated glazing, the adhesive layer of PVB 246 is deposited on the infra red reflecting coating 253. That is, conveniently the layer of PVB 246, the PET ply 252 and the infra red reflecting coating 253 are joined prior to being incorporated in the laminated glazing, being a composite ply of the type described with reference to the figures 1, 2 and 3 and which may be made in accordance with WO97/03763A1. In an alternative embodiment than shown, the orientation of the film 251 may be reversed such that the PET ply 252 is in contact with the adhesive layer of PVB 246.

Joined to the PET ply 252 is another layer of PVB 254. The layer of PVB 254 is 0.76mm thick.

Joined to the layer of PVB 254 is an SPD film 255. The SPD film is between and in contact with the layer of PVB 254 and another layer of PVB 257. The layer of PVB 257 is 0.76mm thick.

The layer of PVB 257 is joined to a plastic ply 256, such a polycarbonate or PET. The plastic ply 256 is between and in contact with the layer of PVB 257 and a layer of PVB 247. The layer of PVB 247 is 0.76mm thick. The ply of PVB 247 is joined to the second pane of glass 244. On "surface 4" (S4) there is an obscuration band 243' and a fade out band

245 'extending around the periphery of the pane 244. The second pane of glass 244 has a thickness of 2.1mm.

It is evident from the above that the interlay er structure that joins the first pane 242 to the second pane 244 consists in contact sequence of the adhesive layer 246, the infra red reflecting coating 253, the PET ply 252, the adhesive layer 254, the SPD film 255, the adhesive layer 257, the plastic ply 256 and the adhesive layer 247.

Although in figure 9 the SPD film 255 is shown as extending to the edge of the laminated glazing, it is preferable to have the SPD film inboard of the edge of the laminated glazing but positioned such that the edges of the SPD film are below the obscuration band 243.

In an alternative to the embodiment shown in figure 9, the positions of the SPD film 255 and the plastic ply 256 may be switched. In another alternative embodiment than shown in figure 9, the plastic ply 256 may be replaced with a glass ply.

The exposed surface of glass pane 244 is "surface 4" (S4) of the laminated glazing 241. However depending upon the orientation of the laminated glazing when installed, the naming of the surfaces may change according to the convention defined with reference to figure 4. On "surface 4" (S4) an obscuration band 243' and a fade out band 245' is positioned. The obscuration band 243' and the fade out band 245' are about 12μιη thick.

In a variant of the laminated glazing shown in figure 9, there is no fade out band 245' on "surface 4" (S4).

Each of the glass panes 242, 244 is a soda-lime-silica composition having a composition as defined in BS EN 572-1 and BS EN 572-2 (2004). The iron content of the glass pane, expressed as a % by weight Fe₂C"3 is about 0.05% by weight Fe₂03.

Figure 10 shows a cross sectional view of a portion of another laminated glazing 61 comprising an SPD film. For clarity only half of the cross section is shown and the cross section of the laminated glazing 61 is symmetrical about the line A- A' .

The laminated glazing 61 has a first pane of glass 62 joined to second pane of glass 64 via an interlayer structure. The first pane of glass 62 has a thickness of 2.1mm. The exposed surface of the glass pane 62 is "surface 1" (SI) of the laminated glazing. There is an obscuration band 63 and fade out band 65 on the surface of glass ply 62 opposite "surface 1" (SI) i.e. "surface 2" (S2).

There is an adhesive layer of PVB 66 that is in contact with the smooth portion of "surface 2" (S2) of the first pane of glass 62 i.e. that portion of "surface 2" (S2) that does not have the obscuration band and fade out band thereon. The layer of PVB 66 is also in contact with the fade out band 65 and the obscuration band 63. The layer of PVB 66 is 20μπι thick. The obscuration band and fade out band are about 12μπι thick.

The layer of PVB 66 does not extend to the edges of the first pane of glass 62 but instead terminates part way beneath the obscuration band 63.

In contact with the layer of PVB 66 there is an infra red reflecting coating 73. The infra red reflecting coating 73 is very thin compared to the thicknesses of the other components of the laminated glazing, with thicknesses for the infra red reflecting coating 73 in the few angstroms and few nanometres range being typical.

In contact with the infra red reflecting coating 73 is a PET ply 72. The PET ply thickness is typically between 0.01mm and 0.5mm, usually about 50-250μπι. The infra red reflecting coating 73 and the PET ply 72 are each coextensive with the layer of PVB 66. The layer of PVB 66, the infra red reflecting coating 73 and the PET ply 72 may be part of a composite ply of the type described with reference to figures 1, 2 and 3. The positions of the infra red reflecting coating 73 and the PET ply 72 may be reversed. In the example shown in figure 10 the assembly of layer of PVB 66 and infra red reflective coating 73 on PET ply 72 prior to being incorporated in the laminated glazing are a composite ply that may be made in accordance with WO97/03763A1.

An adhesive PVB layer 67 that is 0.76mm thick is in contact with the PET ply 72 and the obscuration band 63. The edges of the PET ply 72 and the infra red reflecting coating 73 are protected from the external environment by the layer of PVB 67 being in contact with the obscuration band 63.

In contact with the layer of PVB 67 is a layer of PVB 68 that is 0.38mm thick. There is a cut out region in the layer of PVB 68 in which a film 70 is positioned. The layer of PVB 68 with cut out region therein frames the film 70. The film 70 comprises a suspended particle emulsion and is often referred to as an SPD film. The cut out region is sized such that when the SPD film 70 is in the cut out region, the entire SPD film is below the infra red reflecting coating 73. Furthermore, the edge of the SPD film 70 is positioned such that when viewed through the glazing the normal to "surface 1" (SI) the obscuration band 63 covers the edge of the SPD film. The edge of the SPD film 70 may coincide with the edge of the infra red reflecting coating 73 but it is preferable for the edge of the SPD film to be beneath the obscuration band 63 and inboard of the edge of the infra red reflecting coating. This ensures that the entire SPD film is below the infra red reflecting coating and provides protection from sunlight.

Typically the edge of the PET ply 72 with the infra red reflecting coating 73 thereon is a distance x from an edge E of the laminated glazing and the associated edge of the SPD film 70 is a distance^ from the edge E of the laminated glazing, Preferably y > x i.e. in a cross section of the laminated glazing the edge of the PET ply 72 with the infra red reflecting coating 73 thereon overlaps the associated edge of the SPD film 70. Preferably the distance y - x is 50mm or less, more preferably 40mm or less, even more preferably 30mm or less.

Suitable electrical connections such as busbars (not shown) are in electrical communication with the SPD film 70 such that the suspended particle emulsion is switchable between the "on" and "off states. The busbars are typically positioned underneath the obscuration band 63 so they are not visible when the glazing is installed.

The upper major surface of the SPD film 70 is in contact with and joined to the layer of PVB 67.

A layer of PVB 69 that is 0.38mm thick is in contact with both the layer of PVB 68 and the lower major surface of the SPD film 70. A second glass pane 64 that is 2.1mm thick is in contact with and joined to the layer of PVB 69.

An obscuration band 63 'and fade out band 65' is on the exposed surface of the ply of glass 64. This exposed surface is "surface 4" (S4) of the laminated glazing. In a variant of the laminated glazing shown in figure 10, there is no fade out band 65' on "surface 4" (S4).

Each of the glass panes 62, 64 is a soda-lime-silica composition having a composition as defined in BS EN 572-1 and BS EN 572-2 (2004). The iron content of the glass panes, expressed as a % by weight Fe₂C"3 is about 0.05% by weight Fe₂C"3, although it may be lower or higher.

The laminated glazing 61 was found to pass all required tests and could be exchanged for the same laminated glazing where the layer of PVB 66 was 0.76mm thick instead of the 20μπι thick layer of PVB used in this example of the invention.

Although the laminated glazings shown in figures 8, 9 and 10 are shown as being flat in cross section, they may be curved, for example as shown in figure 6.

Although the laminated glazings shown in figures 8, 9 and 10 have PVB layers, other adhesive layers may be used, for example EVA or TPU.

As is well known in the art, the adhesive layers of PVB, EVA, TPU etc are conveniently available in sheet form prior to being laminated. Such sheets are often referred to as interlayers.

The infra red reflecting coating shown in figures 8, 9 and 10 may be any coating that reflects infra red energy. The infra red reflecting coating may also effect visible radiation passing through the coating or reflected therefrom. The exact nature of the infra red reflecting coating may be chosen for the specific application, for example the infra red reflecting coating may have a high visible light transmission or may be configured to have a desired visible colour in transmission and/or reflection.

The glazings 141, 241 and 61 may be a vehicle glazing, for example a sunroof.

Although the laminated glazings shown in figures 8, 9 and 10 have an SPD film incorporated therein, the SPD film may be replaced by an LCD film.

Figure 11 shows a plan view of a laminated glazing 81 according to the present invention comprising first and second panes of curved glass and having an obscuration band 83 and a fade out band 85 on "surface 2" (S2). A similar obscuration band 83' and fade out band 85' is on "surface 4" (S4) of the laminated glazing 81. The laminated glazing 81 may have the construction as shown in figures 8, 9 or 10 and may be flat or curved. The obscuration band 83 and fade out band 85 extend around the periphery of the panes of glass as shown. The width of the obscuration band 83 and fade out band 85 is substantially constant around the periphery except there is a portion 87 where the obscuration band and fade out band extend more towards the geometric centre of the major surface of the laminated glazing.

Methods of making a laminated glazing according to the first aspect of the present invention shall now be described.

The laminated glazing 141 shown in figure 8 may be made as follows. A first pane of glass 142 having an obscuration band 143 and a fade out band 145 on a major surface thereof is positioned horizontally on a table or the like with the obscuration band 143 and fade out band 145 facing upwards. The first pane of glass is 2.1mm thick.

A composite ply 15 (reference numeral not indicated on figure 8 for clarity) consisting of an adhesive layer 146 joined to an infra red reflecting film 151 is provided. The infra red reflecting film 151 is a PET ply 152 having an infra red reflecting coating on a major surface thereof. The composite ply has the infra red reflecting coating 153 between the adhesive layer 146 and the PET carrier ply 152 although in an alternative embodiment the composite ply has the PET carrier ply between the adhesive layer 146 and the infra red reflecting coating 153. The PET carrier ply 152 is about ΙΟΟμπι thick and the adhesive layer 146 is 20μπι thick. The composite ply is configured to be coextensive with the first pane of glass 142.

The composite ply 15 is laid on the first pane of glass 142 such that the adhesive layer 146 contacts the obscuration band 143, the fade out band 145 and the surface of the glass pane 142 between the edges of the fade out band 145.

Next a ply of PVB 154 that is 0.76mm thick is laid on the composite ply such that the ply of PVB 154 contacts the PET ply 152. The ply of PVB 154 is coextensive with the composite ply 15 and the first pane of glass 142.

Next an SPD film 155 is laid on the PVB ply 154. The SPD film is coextensive with the ply of PVB 154, the composite ply 15 and the first pane of glass 142.

Next a ply of PVB 147 that is 0.76mm thick is lad on the SPD film 155. The ply of PVB 147 is coextensive with the SPD 155, the ply of PVB 154, the composite ply 151 ' and the first pane of glass 142.

Next a second pane of glass 144 that is 2.1mm thick and having an obscuration band 143' and a fade out band 145' on a major surface thereof is laid on the ply of PVB 147 such the obscuration band 143' and fade out band 145' face upwards. The second pane of glass 144 is coextensive with the ply of PVB 147, the SPD film 155, the ply of PVB 154, the composite ply 15 and the first pane of glass 142.

The assembly of second pane of glass 144, ply of PVB 147, SPD film 155, ply of PVB 154, composite ply 15 and first pane of glass 142 are then laminated together at suitably high temperature and pressure to produce the laminated glazing 141.

Figure 12 shows an exploded cross sectional view of the laminated glazing 61, a portion of which is shown in figure 10 and described with reference thereto.

The laminated glazing 61 is manufactured as follows. First an obscuration band 63 and a fade out band 65 are deposited onto one of the major surfaces of a first pane of glass 62 by a suitable process such as screen printing a suitable ink. The ink is then fired at suitably high temperature to fire the obscuration band 63 and fade out band 65 onto the surface of the first pane of glass 62. The firing may be part of another processing step requiring the glass temperature to be raised, for example thermally toughening or bending. The bending may be gravity bending on a mould or bending using a pair of complementary moulding members.

After being fired and then subsequently cooled to ambient conditions, the obscuration band 63 and fade out band 65 are intimately connected to the surface of the first pane of glass

62 but are slightly raised with respect to thereto. The result is that the entire surface having the obscuration band and fade out band thereon is not smooth.

The first pane of glass 62 having the obscuration band 63 and fade out band 65 on a major surface thereof is laid out horizontally on a table or the like with the obscuration band

63 and fade out band 65 facing upwards.

Next composite ply 7 is provided. The composite ply 7 consists of a layer of PVB 66 on one side, a PET ply 72 on the other side and an infra red reflecting coating 73 in between the layer of PVB 66 and the PET ply 72. The layer of PVB 66 is 20μπι thick. The PET ply 72 is 50μπι thick and the infra red reflecting coating 73 is lOOnm thick. The layer of PVB 66, the PET ply 72 and the infrared reflecting coating 73 are each coextensive with each other.

The composite ply 7 is laid on top of the pane of glass 62 such that the PVB layer 66 contacts the glass surface, the fade out band 65 and the obscuration band 63. The composite ply 7 is sized such that the edge of the composite ply 7 lies within the obscuration band and not at the edge of the pane of glass 62.

Next a ply of PVB 67 is laid on top of the composite ply 7 . The ply of PVB 67 is sized to be coextensive with the pane of glass 62. Since the dimensions of the composite ply 7 are smaller than the dimensions of the pane of glass 62 the ply of PVB 67 contacts the upper surface of the composite ply (which corresponds to the surface of PET ply 72) and the obscuration band 63. The PVB ply 67 is 0.76mm thick.

Next a ply of PVB 68 that is 0.38mm thick is laid on top of the ply of PVB 67. The ply of PVB 68 has a cut-out region therein. Preferably the cut-out region extends from the top surface to the bottom surface of the ply of PVB 68. Next an SPD film 70 is positioned in the cut-out region such that the SPD film 70 is framed by the ply of PVB 68.

Next a ply of PVB 69 that is 0.76mm thick is placed on top of the PVB ply 68 having the SPD film located in a cut-out region therein. Consequently the ply of PVB 69 is also placed on top of the SPD film 70.

Finally a second pane of glass 64 having an obscuration band 63' and a fade out band

65' thereon is laid on top of PVB ply 69, such that the obscuration band 63' and fade out band 65' are facing upwards.

The assembly of first pane of glass 62, composite ply 71 ', PVB ply 67, PVB ply 68 having SPD film 70 located in a cut-out region therein, PVB ply 69 and second pane of glass 64 is then subjected to suitable lamination conditions to produce the laminated glazing 61.

The first pane of glass 62 is joined to the second pane of glass 64 via an interlayer structure consisting of composite ply 71 ', PVB ply 67, PVB ply 68 having SPD film 70 located in a cut-out region therein and PVB ply 69.

In an alternative to the above method of making the laminated glazing 61, the composite ply 71 ' has the positions of the PET ply 72 and infrared reflecting coating 73 reversed, such that the PET ply 72 is between the adhesive layer 66 and the infrared reflecting coating 73. Otherwise the process steps are the same.

It will be readily apparent that it is possible to make the laminated glazing 61 by first positioning the pane of glass 64 on a table, and then placing the PVB ply 69 on the glass pane 64 i.e. on "surface 3" (S3). Next the PVB ply 68 having a cut out region therein can be positioned on the PVB ply 69. The SPD film 70 can then be located in the cut out region in the PVB ply 68. Next the PVB ply 67 can be placed on the PVB ply 68 having the SPD film

70 located in a cut out region therein. Next the composite ply 71 ' can be placed on the PVB ply 67. Finally the pane of glass 62 can be placed on the composite ply 5 . This assembly can then be subjected to suitable pressure and temperature to produce the laminated glazing

61.

The present invention has the particular advantage that a laminated glazing may be manufactured comprising two panes of glazing material, an infra red reflecting coating on a carrier ply and an obscuration band on an inner facing surface of one of the panes of glazing material and an SPD film, such that there is reduced optical distortion. This is particularly important for a glazing comprising an SPD film because the SPD film has a low light transmission state that makes the optical distortion more readily apparent, particularly in reflection.

Although the examples described herein have at most four adhesive layers, it will be readily apparent that there may be more than four adhesive layers. Furthermore, although the laminated glazing has a first pane of glazing material and a second pane of glazing material, it will be readily apparent that there may be additional (i.e. one or more) plastic layers or panes of glazing material i.e. glass, in between the first pane of glazing material and the second pane of glazing material.

Although an SPD film has been used in certain examples, the SPD film may be replaced by other electrically actuated films such as liquid crystal display films.

Laminated glazings according to the first aspect of the present invention find particular application as windows for vehicles or buildings. When used as a vehicle window, the window may be a windscreen, rear window, side window or sunroof.

Claims

1. A laminated glazing comprising a first pane of glazing material and a second pane of glazing material, the first pane of glazing material having a first major surface and an opposing second major surface, there being an obscuration band on the second major surface extending around at least a portion of the periphery of the first pane of glazing material such that the second major surface is not smooth, the first pane of glazing material being joined to the second pane of glazing material by an interlayer structure comprising a first adhesive layer having a thickness of between 6μιη and ΙΟΟμιη, a carrier ply having an infra red reflecting coating on a surface thereof, a second adhesive layer thicker than the first adhesive layer and a film comprising an electrically actuated layer, wherein the first adhesive layer is between the first pane of glazing material and the carrier ply and the first adhesive layer contacts a portion of the second major surface of the first pane of glazing material and a portion of the obscuration band; the carrier ply is between the first adhesive layer and the film; the film is either (i) between the second adhesive layer and the carrier ply or (ii) between the second adhesive layer and the second pane of glazing material; the infra red reflecting coating is between the first adhesive layer and the second adhesive layer; the first adhesive layer and the second adhesive layer are between the first pane of glazing material and the second pane of glazing material; and the second adhesive layer is in contact with the second pane of glazing material.

2. A laminated glazing according to claim 1, wherein the obscuration band comprises a fade out band and the first adhesive layer contacts at least a portion of the fade out band.

3. A laminated glazing according to claim 2, wherein the thickness of the fade out band is between Ιμιτι and 150μιη, more preferably between Ιμιτι and ΙΟΟμιη, even more preferably between 5μιη and ΙΟΟμιη.

4. A laminated glazing according to any of the preceding claims, wherein the thickness of the obscuration band is between Ιμπι and 150μιη, more preferably between Ιμπι and ΙΟΟμιη, even more preferably between 5μιη and ΙΟΟμιη.

5. A laminated glazing according to any of the preceding claims, wherein the first adhesive layer has a thickness between ΙΟμπι and ΙΟΟμπι, preferably between 13μπι and 76μπι.

6. A laminated glazing according to any preceding claim, wherein the second adhesive layer has a thickness between 0.1mm and 2mm, preferably between 0.1mm and 1mm, more preferably between 0.2mm and 0.8mm.

7. A laminated glazing according to any preceding claim, wherein the laminated glazing comprises a third adhesive layer and the film is between the second adhesive layer and the third adhesive layer.

8. A laminated glazing according to any preceding claim, wherein the film is located in a cut out region in an adhesive layer that is between the second adhesive layer and the carrier ply.

9. A laminated glazing according to claim 8 when appendent upon claim 7, wherein the film is located in a cut out region in a fourth adhesive layer, and the fourth adhesive layer is between the second adhesive layer and the third adhesive layer.

10. A laminated glazing according to any of the preceding claims, wherein at least a portion of an edge of the film is in registration with the obscuration band.

11. A laminated glazing according to any of the preceding claims, wherein one or more edges of the film lie within the perimeter defined by the periphery of the infra red reflecting coating.

12. A laminated glazing according to any of the preceding claims, wherein the entire perimeter of the film lies within the perimeter defined by the periphery of the infra red reflective coating.

13. A laminated glazing according to any of the preceding claims, wherein one or more edges of the film lie within the perimeter defined by the periphery of the carrier ply.

14. A laminated glazing according to any of the preceding claims, wherein the entire perimeter of the film lies within the perimeter defined by the periphery of the carrier ply.

15. A laminated glazing according to any of the preceding claims, wherein the film is coextensive with infra red reflecting coating.

16. A laminated glazing according to any of the preceding claims, wherein the infra red reflecting coating is coextensive with the carrier ply.

17. A laminated glazing according to any preceding claim, wherein the visible light transmission calculated according to BS EN410 through a portion of the laminated glazing not covered with the obscuration band is at least 70% or is less than 70%, preferably less than 50%), more preferably less than 10%>, most preferably less than 5%.

18. A laminated glazing according to any preceding claim wherein the carrier ply is a plastic ply, preferably a polyester, more preferably polyethylene terephthalate.

19. A laminated glazing according to any preceding claim wherein the first adhesive layer comprises polyvinyl butyral.

20. A laminated glazing according to any preceding claim, wherein the second adhesive layer comprises polyvinyl butyral. a copolymer of ethylene or polyurethane.

21. A laminated glazing according to any preceding claim, being a vehicle glazing, in particular a sunroof for a vehicle.

22. A laminated glazing according to any preceding claim, wherein the film comprising the electrically actuated layer comprises an SPD film or an LCD film.

23. A method of making a laminated glazing comprising the steps: (i) providing a first pane of glazing material having a first major surface and an opposing second major surface; there being an obscuration band on a portion of the second major surface;

(ii) positioning a composite ply onto the second major surface of the first pane of glazing material, the composite ply comprising a carrier ply having an infra red reflecting coating on at least a portion of a major surface thereof and a first layer of adhesive, the first layer of adhesive having a thickness between 6μιη and ΙΟΟμιη, the composite ply being positioned onto the second major surface of the first pane of glazing material such that the first layer of adhesive contacts the obscuration band;

(iii) positioning a film comprising an electrically actuated layer on the composite ply;

(iv) positioning a second adhesive layer on the composite ply such that either (a) the film is between the first adhesive layer and the second adhesive layer, or (b) that the second adhesive layer is between the film and the composite ply;

(v) positioning a second pane of glazing material on the second adhesive layer; and.

(vi) applying suitably high temperature and pressure to laminate the first sheet of glazing material to the second pane of glazing material via the first adhesive layer and the second adhesive layer.

24. A method according to claim 23 wherein the second adhesive layer is between the film and the composite ply, and wherein before step (v) a third adhesive layer is positioned on the film such that the film is between the third adhesive layer and the second adhesive layer.

25. A method according to claim 23 or claim 24, wherein the film comprising the electrically actuated layer comprises an SPD film or an LCD film.