EA048106B1 - WINDSHIELD INDICATOR SYSTEM - Google Patents

Description

Field of technology to which the invention relates

The invention relates to a coated substrate comprising a transparent substrate provided with a reflective coating for p-polarised light, to multi-layer glazing and a head-up display (HUD) system comprising said coated substrate.

Prerequisites for the creation of an invention

Head-up display systems, or HUD systems, are widely used in transportation devices to provide information on the glass of a vehicle within the field of view of a viewer or driver of said vehicle.

There are many different types of HUD systems. Usually, the projection system is combined with a translucent mirror (translucent reflector and translucent window) as the final optical component to form a projected image that the user can see. At the same time, the user can see other surrounding views through the translucent mirror. The translucent mirror is an important component that affects the usability of the display panel. In general, the reflectivity of the translucent mirror should be sufficient to reflect the light from the projector, but the translucent mirror should also be transparent enough to provide an adequate view through it.

Examples of a HUD system are given in document CN104267498A for a head-up display panel system comprising a projection light source, a laminated glass and a transparent nanometer film, wherein the transparent nanometer film comprises at least one laminated structure of alternating high reflectivity layers and low reflectivity layers that are sequentially deposited outward from the surface of an inner glass panel; wherein the projection light source is used to generate p-polarized light, the p-polarized light is incident on the transparent nanometer film, the reflectivity of the p-polarized light from the transparent nanometer film is at least 5% and the angle of incidence of the p-polarized light is in the range of from 42° to 72°. Similar examples of systems that are HUD systems using p-polarized light are given in documents CN206147178U and CN204166197U.

Other examples of HUD systems are given in document US2O19/O64516A1. Examples of a projection assembly for a vehicle are given in document WO2020/083649A1.

HUD systems take advantage of a coating or a set of thin layers deposited in the path of the projected light, which serve to reflect said projected light. The projected light may be polarized, such as s-polarized light or p-polarized light, or the projected light may not be polarized.

When used in HUD systems that use p-polarized incident light, the reflectivity of p-polarized light (Rp-pol) is considered sufficient when it reaches 10% at an incident angle of 65° of said p-polarized light. However, it is very important that the overall reflection from the instrument panel does not affect the driver's viewing quality.

Thus, there remains a need for a reflective coating for p-polarized light that provides optimized reflection of p-polarized light while minimizing reflection from the instrument panel, reflecting a clear and crisp image presentation on the glass in the HUD system.

The essence of the invention

The present invention provides a coated substrate comprising a transparent substrate provided with a reflective coating for p-polarized light, sequentially comprising, starting from the surface of the substrate:

a) optional:

i) a first coating comprising one or more layers with a high refractive index, the first coating having a thickness of from 1 to 100 nm, and ii) a second coating comprising one or more layers with a low refractive index, the second coating having a thickness of from 1 to 220 nm, and

b) a third coating consisting of one or more high refractive index layers, the third coating having a thickness of from 40 to 150 nm, and

c) a fourth coating consisting of one or more layers with a low refractive index, wherein the fourth coating has a thickness of from 40 to 200 nm, and further comprising at least one first layer of absorbing material, wherein said at least one first layer of absorbing material has a thickness of from 0.2 to 15 nm, and said absorbing material has an average refractive index n greater than 1 and an average extinction coefficient k greater than 0.1, wherein the average values of n and k are calculated based on values at wavelengths of 450 nm, 550 nm and 650 nm.

The present invention further provides a laminated glass comprising said coated substrate and a HUD system comprising said coated substrate.

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Finally, the use of said coated substrate in a HUD system is provided, comprising a p-polarized light source that projects light at an incidence angle onto the glazing from 42° to 72° in the plane of incidence.

Detailed description of the invention

The present invention provides a coated substrate comprising a transparent substrate provided with a reflective coating for p-polarized light, sequentially comprising, starting from the surface of the substrate:

a) optional:

i) a first coating comprising one or more layers with a high refractive index, the first coating having a thickness of from 1 to 100 nm, and ii) a second coating comprising one or more layers with a low refractive index, the second coating having a thickness of from 1 to 220 nm, and

b) a third coating consisting of one or more high refractive index layers, the third coating having a thickness of from 40 to 150 nm, and

c) a fourth coating consisting of one or more layers with a low refractive index, wherein the fourth coating has a thickness of from 40 to 200 nm, and further comprising at least one first layer of absorbing material, wherein said at least one first layer of absorbing material has a thickness of from 0.2 to 15 nm, and said absorbing material has an average refractive index n greater than 1 and an average extinction coefficient k greater than 0.1, wherein the average values of n and k are calculated based on values at wavelengths of 450, 550 and 650 nm.

In the context of the present invention, a reflective coating for p-polarized light is intended to describe a coating or a set of thin layers capable of reflecting incident p-polarized light at any angle of incidence.

The transparent substrate may be a glass substrate or a plastic substrate comprising or consisting of poly(methyl meth)acrylate (PMMA), polycarbonates, polyethylene terephthalate (PET), polyolefins, polyvinyl chloride (PVC), or mixtures thereof.

The transparency of the substrate is taken into account if the light transmittance (T) is more than 10%, alternatively more than 20%, alternatively more than 30%.

The predominantly transparent substrate is a glass substrate.

The glass may be of any type, such as regular float glass or flat glass, and may have any composition that has any optical properties, such as any visible transmittance greater than 10%, ultraviolet transmittance, infrared transmittance, and/or total solar transmittance.

The glass may be soda-lime, borosilicate, crystal glass, or aluminosilicate glass. The glass may be a regular clear, colored, or ultra-clear (i.e., lower Fe content and higher transmittance) glass substrate. Additional examples of glass substrates include clear, green, bronze, or blue-green glass substrates.

The composition of the glass is not particularly important for the purpose of the present invention, provided that said glass sheet is suitable for applications in the field of transportation or construction. The glass may be clear glass, extra clear glass or coloured glass containing one component/colourant or several components/colourants in the appropriate amount depending on the desired effect. Coloured glass includes grey, green or blue float glass. In some circumstances, coloured glass may be advantageous to ensure the appropriate and desired colour of the completed glazing within the limitations of the applicable legislation.

A particularly suitable coloured glass may be green glass, since it provides an excellent appearance when viewed from the outside of the vehicle. Green glass may, for example, be soda-lime glass with iron oxide in the form of Fe ₂ O ₃ in amounts in the range of 0.3 to 1.0 wt.%. Another type of suitable glass may, for example, be soda-lime glass with iron oxide in the form of Fe ₂ O ₃ in amounts in the range of 0.002-0.06 wt.% and a chromium content in the form of Cr ₂ O ₃ in amounts in the range of 0.0001-0.06 wt.%.

The transparent substrate may have a thickness in the range of 0.5 mm to about 15 mm, alternatively from 1 mm to about 10 mm, alternatively from 1 mm to about 8 mm, alternatively from 1 mm to about 6 mm. In the case of applications in the field of transportation, the glass may have a thickness in the range of 1 to 8 mm, although it can also be thinner or thicker in the case of applications in the field of construction, for example, ultra-thin glass from 0.5 to 1 mm or thicker glass from 8 to 12 mm in addition to a thickness of 1 to 8 mm.

Glass can be flat or fully or partially curved to properly fit a particular glass support design, depending on the shape required for the application.

The glass can be annealed, tempered or heat strengthened glass.

For the purposes of the present invention, the thickness of coatings and thin layers is geometric thickness expressed in nm, unless otherwise specified.

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In the context of the present invention, the high refractive index is typically >1.8, alternatively >1.9, alternatively >2.0, alternatively >2.1 at a wavelength of 550 nm.

In the context of the present invention, the low refractive index is typically <1.7, alternatively <1.6 at a wavelength of 550 nm.

The high refractive index materials of the first optional coating and the third coating may be independently selected from at least one of the oxides of Zn, Sn, Ti, Nb, Zr, Ni, In, Al, Si, Ce, W, Mo, Sb and Bi, and mixtures thereof, or nitrides of Si, Al, Zr, B, Y, Ce and La, and mixtures thereof. That is, the third and first coatings, if present, may have the same or different compositions.

In particular, materials with a high refractive index that can withstand various types of heat treatment can be used, and they can be selected from Zr, Nb, Sn, Zn or Ti oxide;

mixed oxide of two or more of Ti, Zr, Nb, Si, Sb, Sn, Zn, In;

nitride of Si, Zr, Al, B;

mixed nitride of two or more of Si, Zr, Al, B.

In some embodiments of the present invention, the high refractive index materials may be selected from a mixed titanium-zirconium oxide, a mixed titanium-silicon oxide, a mixed niobium-zirconium oxide, a mixed silicon-zirconium nitride, aluminum-doped silicon nitride, zirconium oxide, a mixed indium-tin oxide, a mixed aluminum oxide with a high zinc content, a mixed antimony-tin oxide, a mixed titanium-zinc oxide, a mixed zinc-tin oxide.

In some alternative embodiments of the present invention, the high refractive index materials may be selected from a mixed oxide of titanium and zirconium, a mixed oxide of titanium and silicon, a mixed oxide of niobium and zirconium, a mixed nitride of silicon and zirconium, aluminum-doped silicon nitride, zirconium oxide, a mixed oxide of zinc and tin.

Preferred high refractive index materials for maximum reflection of polarized light include, in descending order of preference due to durability considerations, titanium zirconium mixed oxide, silicon zirconium mixed nitride, titanium silicon mixed oxide, aluminum doped silicon nitride, and zinc tin mixed oxide.

A preferred material for high refractive index coatings is a mixed oxide of titanium and zirconium in a Ti/Zr ratio of 55/45 to 75/25 wt.%, so that the refractive index is >2.0, preferably in a ratio of 65/35 wt.%, or a mixed oxide of titanium and silicon in a Ti/Si ratio of 85/15 to 95/5 wt.%, preferably in a ratio of 92/8 wt.%. Such a coating of mixed oxide of titanium and zirconium provides good chemical and mechanical resistance, stability during heat treatment and very low absorption.

The low refractive index materials of the second optional coating and the fourth coating may be independently selected from silicon oxide, silicon oxynitride, silicon oxycarbide, aluminum oxide, mixed silicon-aluminum oxide, mixed silicon-zirconium oxide, aluminum-doped zinc oxide, or mixtures thereof. The fourth and second coatings, if present, may have the same or different compositions. The low refractive index materials may contain dopants such as aluminum, boron, or zinc. Typically, the dopant concentration in the coating is no more than 10 wt.%.

Preferred mixed oxides of silicon and zirconium contain less than 15 wt.% ZrO, so that the refractive index is <1.7. When improved chemical resistance is expected, such a layer of mixed oxides of silicon and zirconium containing less than 15 wt.% ZrO may be present in the fourth coating and have a thickness of at least 5 nm, alternatively at least 10 nm.

Preferred aluminum-doped zinc oxides (AZOx) contain less than 10 wt.% Al and are substoichiometric such that the refractive index is <1.7.

A preferred material for the low index layer is silicon oxide, optionally doped with aluminum or boron, or a mixed oxide of silicon and aluminum, or a mixed oxide of silicon and zirconium.

The refractive index at a wavelength of 550 nm of the high refractive index materials is higher than the refractive index of the low refractive index materials. The refractive indices of the high and low refractive index materials may differ by at least 0.1, preferably by at least 0.2, more preferably by at least 0.25. Such a difference in refractive indices ensures an optimal contact surface of the material and, therefore, optimal reflection of p-polarized light.

The p-polarized light reflecting coating optionally comprises a first coating consisting of one or more layers of high refractive index materials and a second coating consisting of one or more layers of low refractive index material. An optimal pair of coatings provides improved p-polarized light reflection, but with higher manufacturing costs.

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In the context of the present invention, both the first and second coatings are optionally present in the reflective coating for p-polarized light. That is, when it is necessary to provide an optical effect, both the first and second coatings are present simultaneously.

The optional first coating consists of one or more layers of high refractive index material independently selected from the materials described above. The first coating, if present, may have a thickness of 1 to 100 nm, alternatively 2 to 80 nm, alternatively 4 to 65 nm, alternatively 4 to 15 nm.

The optional second coating consists of one or more layers of low refractive index material independently selected from the materials described above. The second coating, if present, may have a thickness of 1 to 220 nm, alternatively 2 to 210 nm, alternatively 4 to 200 nm, alternatively 100 to 200 nm.

The third coating consists of one or more layers of high refractive index material independently selected from the materials described above. The third coating may have a thickness of 40 to 150 nm, alternatively 45 to 135 nm, alternatively 50 to 125 nm.

The fourth coating consists of one or more layers of a low refractive index material independently selected from the materials described above. The fourth coating may have a thickness of 400 to 200 nm, alternatively 45 to 160 nm, alternatively 50 to 150 nm. In the context of the present invention, the fourth coating is the topmost and last coating of the present reflective coating for p-polarized light.

Thus, each of the first, second, third or fourth coatings may independently consist of a single layer or may comprise two or more layers. The first, second, third or fourth coating may also be referred to as dielectric layers selected from the material lists described above.

In some cases, a lower coating layer may be present in contact with the surface of the transparent substrate. Such a lower coating layer is different from any of the first or second, or third, or fourth coatings. Such a lower coating layer does not provide any optical influence on the reflective coating for p-polarized light, but can function as a diffusion barrier from the substrate or as a seed layer for subsequent layers. In preferred embodiments, the lower coating layer may be present, in particular, in the absence of the first and second coatings.

In some embodiments, when the first and second coatings are absent, the coated substrate comprises a transparent substrate provided with a reflective coating for polarized light, sequentially comprising, starting from the surface of the substrate:

a) a third coating consisting of one or more high refractive index layers, wherein the third coating has a thickness of from 40 to 150 nm, and

b) a fourth coating consisting of one or more layers with a low refractive index, wherein the fourth coating has a thickness of from 40 to 200 nm, and further comprises at least one first layer of absorbing material, wherein said at least one first layer of absorbing material has a thickness of from 0.2 to 15 nm, and said absorbing material has an average refractive index n higher than 1 and an average extinction coefficient k higher than 0.1, wherein the average values of n and k are calculated based on values at wavelengths of 450 nm, 550 nm and 650 nm.

The term absorbing material refers to a material that absorbs part of the visible radiation.

The absorbing material may be characterized by an average refractive index n greater than 1 and an average extinction coefficient k greater than 0.1, where the average values of n and k are calculated from the values of n and k at 3 wavelengths, namely 450 nm, 550 nm and 650 nm.

Thus, the average value of n is calculated using the refractive index values of the material at 3 wavelengths of 450 nm, 550 nm and 650 nm. The average value of k is calculated using the extinction coefficient values of the material at 3 wavelengths of 450 nm, 550 nm and 650 nm.

The person skilled in the art is familiar with the optical parameters n and k. Optical modeling software for thin films, such as Thin Film Center or CODE, has its own databases, but also provides a reliable tool for the person skilled in the art to match optical models of n and k of thin films deposited with a known physical thickness and a characterized substrate.

At least one first layer of absorbing material can be selected from NiCr, W, Nb, Zr, Ta, Pd, Si, Ti or alloys based on Ni and/or Cr and/or W, or alloys based on Cr and Zr or based on W and Zr or Cr, or based on W and Ta, optionally including an additional element selected from Ti, Nb, Ta, Ni and Sn; or from TiN, CrN, WN, NbN, TaN, ZrN, NiCrN or NiCrWN, or a mixture of these nitrides.

Nitrides can also be partially oxidized provided that the absorption is maintained at k above 0.1 in the range from 450 nm to 650 nm.

The absorbent material layer may be provided with at least one barrier layer above and/or below said absorbent layer. Such a barrier layer may have a geometric

- 4 048106 thickness ranging from 5 to 50 nm. Examples of such barrier layers include silicon nitride or aluminum-doped zinc oxide, or titanium oxide, or a mixed oxide of titanium and zirconium.

That is, in some cases, at least one first layer of absorbing material may comprise a NiCr or NiCrW layer provided with at least one barrier of silicon nitride, or be surrounded by a first dielectric coating formed essentially of silicon nitride and a second dielectric coating formed essentially of silicon nitride, each of which independently has a geometric thickness of from 5 to 50 nm; or at least one first layer of absorbing material may comprise a Pd layer surrounded by a first dielectric coating formed essentially of aluminum-doped zinc oxide and a second dielectric coating formed essentially of aluminum-doped zinc oxide, each of which independently has a geometric thickness of from 5 to 50 nm. Such a layer of absorbing material ensures optimal reflection of p-polarized light with optimal absorption of light.

At least one first layer of absorbing material can be preferably selected from NiCr, W, Nb, Pd, Si, Ti or alloys based on Ni and/or Cr and/or W; or from TiN, CrN, WN, NbN, TaN, ZrN, NiCrN or NiCrWN, or a mixture of these nitrides.

At least one first layer of absorbing material may be more preferably selected from NiCr, W, Pd, Si, Ti or alloys based on Ni and/or Cr and/or W; or from TiN, CrN, WN, NiCrN or NiCrWN, or a mixture of these nitrides.

Although not required, heat resistance of the absorbent material may be beneficial, i.e., it preferably remains substantially unchanged when heat treated at temperatures above 400°C.

In some cases, at least one first layer of absorbent material may comprise one or more single layers in contact with each other. In some cases, at least one first layer of absorbent material may have a fractional composition throughout its thickness as provided by the deposition conditions.

In the context of the present invention, the absorbing material does not contain silver. A material such as silver does not provide the necessary enhancement of the reflection of p-polarized light due to its low refractive index n below 1. In addition, in the context of the present invention, the reflective coating for p-polarized light, ultimately present on the surface of the substrate facing the interior of the room (room or vehicle), requires mechanical and chemical resistance, which cannot be provided by a material such as silver, since silver will decompose and/or oxidize under the influence of ambient air, which will make the reflective coating for p-polarized light ineffective.

At least one first layer of absorbent material may have a thickness of from 0.2 to 15 nm, alternatively from 0.5 to 15 nm, alternatively from 2 to 12 nm.

At least one first layer of absorbent material may be:

1) either inserted between at least two adjacent coatings of said first (if present), second (if present), third or fourth coatings,

2) or is inserted within at least one of the said first (if present), second (if present), third or fourth coatings.

When at least one first layer of absorbent material is inserted between at least two adjacent coatings of said first, second, third or fourth coatings, this means that at least one first layer of absorbent material may be inserted between the optional first and second coatings, if present; or inserted between the second, if present, and third coatings; or inserted between the third and fourth coatings.

If said first and second coatings are absent, then at least one first layer of absorbent material may be inserted either between adjacent third or fourth coatings, or within at least one of the third or fourth coatings.

If said first and second coatings are present, at least one first layer of absorbent material may be

1) either inserted between at least two adjacent coatings of said first, second, third or fourth coatings,

2) or inserted within at least one of said first, second, third or fourth coatings.

At least one layer of absorbent material is not in any case located above or above the fourth coating, wherein said fourth coating is the last layer of the set of thin layers.

Such possibilities can be schematically expressed as follows:

backing/H3/ABS/L4, or backing/H1/ABS/L2/H3/L4, or

- 5 048106 substrate/H1/L2/ABS/H3/L4, or substrate/H1/L2/H3/ABS/L4, wherein H1 and H3 represent the first and third coatings (high refractive index coatings), L2 and L4 represent the second and fourth coatings (low refractive index coatings), and ABS represents at least one first layer of absorbent material.

When at least one first layer of absorbent material is inserted inside at least one of said first, second, third or fourth coatings, this means that at least one first layer of absorbent material can be inserted inside the optional first coating, if present; or inside the optional second coating, if present; or inside the third coating; or inside the fourth coating. Indeed, the presence of a plurality of layers provides the possibility of inserting at least one absorbent material inside any one of said coatings.

Such possibilities can be schematically expressed as follows:

substrateα/H3α/ABS/H3b/L4, or substrate/H3/L4a/ABS/L4b, or substrate/H1a/ABS/H1b/L2/H3/L4, or substrate/H1/L2a/ABS/L2b/H3/L4, or substrate/H1/L2/H3a/ABS/H3b/L4, or substrate/H1/L2/H3/L4a/ABS/L4b, wherein H1 and H3 represent the first and third coatings (high refractive index coatings), L2 and L4 represent the second and fourth coatings (low refractive index coatings), each of which is designated by the letters a and b, when said coating is separated by inserting at least one absorbing layer, and ABS represents at least one first layer of absorbing material.

The advantage of the present coated substrate comprising a transparent substrate provided with a reflective coating for p-polarised light is that, when incident p-polarised light is reflected from the coated glass side, the polarisation enhancement factor (PEF) Rp-pol/Rv( _m ) (%) (reflection of p-polarised light/internal reflection in the visible range) is increased by at least 6%, when only the third and fourth coatings are present, alternatively by at least 8%, alternatively by at least 10%, compared to a similar reflective coating for p-polarised light without at least one layer of absorbing material, at an angle of incidence of p-polarised light from 42° to 72°, alternatively at an angle of 65°. When the first, second, third and fourth coatings are present, the polarization enhancement factor (PEF) Rppol/Rv( _m ) increases by at least 3%, compared to a similar reflective coating for p-polarized light without at least one layer of absorbing material, at an incidence angle of p-polarized light from 42° to 72°, alternatively at an angle of 65°. That is, Rp-pol increases, while Rv( _m ) either remains at the same level (with a deviation of no more than 5%) or even decreases. Without being limited by theory, it is believed that the selected layer of absorbing material improves the reflection of p-polarized light from the coated surface, while reducing the overall reflection due to absorption.

The present p-polarized light reflective coating exhibits an increase in absorption compared to a similar p-polarized light reflective coating without its absorbing material layer. The increase in absorption provided by the presence of the absorbing material layer in the p-polarized light reflective coating according to the present invention may be at least 1.5% on transparent glass with illuminant A, CIE 2°. In some cases, the increase may be at least 2%. In some cases, the increase may be at least 5%. In cases where the silver layer can be considered as an absorbing material, unlike the present invention, such an increase in absorption is not observed, i.e. such an increase is <1.5%.

The present p-polarized light reflective coating is considered as a non-conductive coating, i.e. its surface resistance can be >100 ohms/square. This provides the advantage that the present coated substrate comprising a transparent substrate provided with a p-polarized light reflective coating does not require removal of the coating to be compatible for use in advanced driver assistance systems (ADAS) or compatible with electromagnetic communication conducted through glass. This would not be possible if the silver layer was considered as an absorbing material.

The present p-polarized light reflective coating is not considered to be a low-emissivity coating. Low-emissivity coatings may generally have an emissivity of 0.4 or less, or 0.2 or less. On the other hand, the present p-polarized light reflective coating may have an emissivity of more than 0.5, or more than 0.6, or even more than 0.7.

In some cases, a second layer of absorbent material may be present, which differs

- 6 048106 from the first layer of absorbent material, provided that it is in a different position relative to the first layer of absorbent material. Thus, said second layer of absorbent material may be:

1) either inserted between two adjacent layers of dielectric of at least one of the said first (if present), second (if present), third or fourth coatings;

2) or is inserted within at least one of said first (if present), second (if present), third or fourth coatings, wherein the location of the second layer of absorbent material differs from the location of the first layer of absorbent material.

If said first and second coatings are absent, then the second layer of absorbent material may be inserted either between adjacent third or fourth coatings, or within at least one of the third or fourth coatings.

If the first and second coatings specified are present, the second layer of absorbent material may be:

1) either inserted between at least two adjacent coatings of said first, second, third or fourth coatings,

2) or inserted within at least one of said first, second, third or fourth coatings.

If present, the second layer of absorbent material is not in contact with the first layer of absorbent material.

The first and second layers of absorbent material may comprise the same material as discussed above, or may comprise different materials. The method of providing a coated substrate comprises the following steps:

providing a transparent substrate and deposition;

a) optional:

i) a first coating consisting of one or more layers with a high refractive index, wherein the first coating has a thickness of from 1 to 100 nm, and ii: a second coating consisting of one or more layers with a low refractive index, wherein the second coating has a thickness of from 1 to 220 nm, and b: a third coating consisting of one or more layers with a high refractive index, wherein the third coating has a thickness of from 40 to 150 nm, and c: a fourth coating consisting of one or more layers with a low refractive index, wherein the fourth coating has a thickness of from 40 to 200 nm, and further depositing at least one first layer of absorbing material so that said first layer of polarization enhancing material is either inserted between at least two adjacent coatings of said first, second, third or fourth coatings, or is inserted within at least one of said first, second, third or fourth coatings.

The deposition methods of different coatings include chemical vapor deposition (CVD), plasma-enhanced chemical vapor deposition (PECVD), physical vapor deposition (PVD), magnetron sputtering, wet coating, etc. Different layers of the corresponding coatings can be deposited using different technical solutions.

In some embodiments, the low refractive index layers of the fourth and optional second coatings may be deposited by a PECVD method, such as a hollow cathode PECVD method. This method provides the additional benefit of reduced costs and high deposition rates.

The step of depositing at least one first layer of absorbing material should be performed in such a way that it is not completely oxidized, so that it can act as an effective layer that enhances the polarization. Therefore, the gas atmosphere during deposition is preferably argon, nitrogen or a mixture of argon and nitrogen. Oxidation can occur during the deposition of the subsequent layer, but for the implementation within the framework of the present invention, a minimum thickness of the non-oxidized absorbing material of at least 0.2 nm is required.

The deposition step may be followed by a heat treatment step. Varieties of heat treatment include heating the glazing to a temperature of at least 560°C in air, such as from 560°C to 700°C, in particular from about 640°C to 670°C, for about 3, 4, 6, 8, 10, 12 or even 15 minutes, depending on the type of heat treatment and the thickness of the glazing. The treatment may include a rapid cooling step after the heating step to introduce a stress difference between the surfaces and the core of the glass so that in the event of an impact the sheet of so-called toughened glass breaks safely into small pieces. If the cooling step is carried out under milder conditions, then the glass will simply become heat strengthened and will in any case have improved mechanical resistance.

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The present invention also provides a multilayer glazing comprising an outer panel having a first surface and a second surface, and an inner panel having a first surface and a second surface, wherein both sheets are bonded by at least one sheet of an intermediate layer material that provides contact between the first surface of the inner panel and the second surface of the outer panel, wherein the inner sheet is a coated substrate comprising a transparent substrate provided with a reflective coating for polarized light on its second surface, sequentially comprising, starting from the surface of the substrate:

1) optional:

i) a first coating comprising one or more layers with a high refractive index, the first coating having a thickness of from 1 to 100 nm, and ii) a second coating comprising one or more layers with a low refractive index, the second coating having a thickness of from 1 to 220 nm, and

2) a third coating consisting of one or more layers with a high refractive index, wherein the third coating has a thickness of from 40 to 150 nm, and

3) a fourth coating consisting of one or more layers with a low refractive index, wherein the fourth coating has a thickness of 40 to 200 nm, and further comprising at least one first layer of absorbing material, wherein said at least one first layer of absorbing material has a thickness of 0.2 to 15 nm, and said absorbing material has an average refractive index n higher than 1 and an average extinction coefficient k higher than 0.1, wherein the average values of n and k are calculated based on values at wavelengths of 450 nm, 550 nm and 650 nm.

That is, the present invention also relates to a multilayer glazing comprising at least two panels bonded together by at least one sheet of interlayer material, wherein at least one of the panels is a coated substrate as described above. The panels may be selected from the transparent substrates described above.

The multilayer glazing comprises an outer panel having a first surface (P1) and a second surface (P2), and an inner panel having a first surface (P3) and a second surface (P4). The outer panel of the multilayer glazing is the panel that is in contact with the external environment of the vehicle or building. The inner panel is the panel that is in contact with the internal space of the vehicle or building. The two panels are held in contact with an overlapping sheet or intermediate layer that serves to ensure adhesion and contact between the two sheets of glass. The intermediate layer ensures contact between the first surface (P3) of the inner panel and the second surface (P2) of the outer panel.

In the present multilayer glazing, the coated substrate is an inner panel, and said sheet is present in the multilayer glazing, so that the reflective coating for p-polarized light is present on the second surface of the inner panel, i.e. on P4. Thus, the second surface of the inner panel is provided with a reflective coating for p-polarized light and, thus, is an open surface of the multilayer glazing facing the interior of the vehicle or building.

The intermediate layer typically contains thermoplastic materials such as polyvinyl butyral (PVB), ethylene vinyl acetate (EVA), polyurethane (PU), polyethylene terephthalate (PET), polycarbonate or several layers thereof, typically with a total thickness of 0.3 to 0.9 mm. The intermediate layer may contain dyes and therefore may be a colored intermediate layer.

In some cases where the transparent substrate is colorless, the interlayer may be a colored interlayer. Such a colored interlayer may provide a superior appearance to an outside observer.

The intermediate layer may have a uniform thickness over its entire surface between the two panels or may have an uneven thickness over its entire surface, i.e. the intermediate layer may be a wedge-shaped intermediate layer.

The intermediate layer may comprise a light absorbing material or any other polymers that cause light interference if required by the end use, provided that the original purpose of the present invention is not compromised.

In the context of the present invention, a reflective coating for infrared (IR) radiation, comprising n layers based on a reflective functional layer for infrared (IR) radiation and n+1 dielectric layers, wherein each layer based on a reflective functional layer for IR radiation is located between two dielectric layers, may optionally be provided between the outer panel and the inner panel of the multilayer glazing. That is, the reflective coating for infrared (IR) radiation may be applied to at least one of the first surface of the inner panel (P3) or the second surface of the outer panel (P2) or embedded in the intermediate layer.

Thus, the present multilayer glazing may additionally contain, at least

- 8 048106 at least one of the first surface of the inner panel or the second surface of the outer panel or in the form built into the intermediate layer, a reflective coating for infrared radiation, comprising n layers based on a reflective functional layer for IR radiation and n+1 dielectric layers, wherein each layer based on a reflective functional layer for IR radiation is located between two dielectric layers. Such reflective coatings for infrared radiation, as a rule, can be characterized by an emissivity of 0.1 or less, or preferably 0.08 or less, or more preferably 0.05 or less.

The IR coating is compatible with all previous embodiments described above. Such an IR coating does not interfere with the functions of the reflective coating for p-polarized light, i.e., the reflective coating for p-polarized light still provides a reflection of p-polarized light suitable for reflecting a clear and distinct image presentation on the glass in the HUD system.

Within the framework of the present invention, the terms below, below, under indicate the relative position of a layer relative to the next layer within a sequence of layers, starting from the substrate. Within the framework of the present invention, the terms above, top, on, on indicate the relative position of a layer relative to the next layer within a sequence of layers, starting from the substrate.

In the context of the present invention, the relative positions of the layers in the IR coating do not necessarily imply direct contact. That is, some intermediate layer may be provided between the first and second layers. In some cases, the layer may actually consist of several separate layers (or sublayers).

In some cases, the relative position may imply direct contact and this will be indicated.

The IR reflective metallic functional layer (or functional layer) may be made of silver or aluminum, or alloys thereof, ultimately alloyed with less than 15 wt.% platinum, palladium or gold. The functional layer may have a thickness of 5 to 22 nm, alternatively 7 to 20 nm, alternatively 8 to 18 nm. The range of thickness of the functional layer will affect the conductivity, emissivity, solar control function and light transmission of the second coating.

The dielectric layers may typically comprise oxides, nitrides, oxynitrides or oxycarbides of Zn, Sn, Ti, Zr, In, Al, Bi, Ta, Mg, Nb, Y, Ga, Sb, Mg, Si and mixtures thereof. These materials may optionally be alloyed, with examples of alloying additives including aluminum, zirconium or mixtures thereof. The alloying additive or mixture of alloying additives may be present in an amount of up to 15 wt.%. Typical examples of dielectric materials include, but are not limited to, silicon-based oxides, silicon-based nitrides, zinc oxides, tin oxides, zinc-tin mixed oxides, silicon nitrides, silicon oxynitrides, titanium oxides, aluminum oxides, zirconium oxides, niobium oxides, aluminum nitrides, bismuth oxides, silicon-zirconium mixed nitrides, and mixtures of at least two of these, such as, for example, titanium-zirconium oxide.

The IR coating may comprise a seed layer below at least one functional layer, and/or the coating may comprise a barrier layer on at least one functional layer. This functional layer may be provided by either the seed layer or the barrier layer, or both. The first functional layer may be provided by any one or both of the seed and barrier layers, and the second functional layer may be provided by any one or both of the seed and barrier layers, etc. These designs are not mutually exclusive. The seed and/or barrier layers may have a thickness of 0.1 to 35 nm, alternatively 0.5 to 25 nm, alternatively 0.5 to 15 nm, alternatively 0.5 to 10 nm.

The IR coating may also comprise a thin layer of ablative material having a thickness of < 15 nm, alternatively < 9 nm, which is provided in contact with and above the at least one functional layer, and which may be selected from the group consisting of titanium, zinc, nickel, aluminum, chromium and mixtures thereof.

The IR coating may optionally comprise a surface coating or topcoat as the final layer intended to protect the underlying assembly from damage. Such a surface coating comprises oxides of Ti, Zr, Si, Al or mixtures thereof; nitrides of Si, Al or mixtures thereof; carbon-based layers (such as graphite or diamond-like carbon).

Examples of IR coatings include those coatings that comprise an infrared (IR) radiation reflecting layer in contact with and located between a first and second layer, wherein said second layer comprises NiCrOx; and wherein at least said second layer comprising NiCrOx has such a degree of oxidation that a first portion of said second layer near said infrared (IR) radiation reflecting layer is less oxidized than a second portion of said second layer located further from said infrared (IR) radiation reflecting layer.

Examples of IR coatings also include those coatings that contain a dielectric layer;

- 9 048106 a first layer containing zinc oxide located over a dielectric layer; an infrared (IR) radiation reflecting layer containing silver located over and in contact with the first layer containing zinc oxide; a layer containing NiCr oxide located over and in contact with the IR radiation reflecting layer; a second layer containing zinc oxide located over and in contact with the layer containing NiCr oxide; and another dielectric layer located over the second layer containing zinc oxide;

or those coatings that comprise a first dielectric layer; a first infrared (IR) reflecting layer containing silver located on top of at least the first dielectric layer; a first layer containing zinc oxide located on top of at least the first IR reflecting layer and the first dielectric layer; a second IR reflecting layer containing silver located on top of and in contact with the first layer containing zinc oxide; a layer containing NiCr oxide located on top of and in contact with the second IR reflecting layer; a second layer containing zinc oxide located on top of and in contact with the layer containing NiCr oxide; and another dielectric layer located on top of at least the second layer containing zinc oxide.

Further suitable examples of IR coatings include a solar control coating comprising a base dielectric layer comprising at least a base dielectric bottom layer and a base dielectric top layer having a composition different from the composition of the base dielectric bottom layer, wherein the base dielectric top layer comprises any one of zinc oxide or a mixed oxide of Zn and at least one additional material X, wherein the X/Zn ratio in the base dielectric top layer is from 0.02 to 0.5 by weight, and wherein X is one or more materials selected from the group consisting of Sn, Al, Ga, In, Zr, Sb, Bi, Mg, Nb, Ta and Ti, a first metallic infrared reflective layer such as silver or aluminum, or mixtures thereof, ultimately doped with less than 15 wt.% platinum, palladium or gold, a first barrier layer, a central dielectric layer comprising at least a central dielectric bottom layer and a central dielectric top layer having a composition different from the composition of the central dielectric bottom layer, wherein the central dielectric bottom layer is in direct contact with the first barrier layer and the central dielectric top layer; the central dielectric top layer comprises any one of zinc oxide or a mixed oxide of Zn and at least one additional material Y, in which the Y/Zn ratio in the main dielectric top layer is from 0.02 to 0.5 by weight, and in which Y is one or more materials selected from the group consisting of Sn, Al, Ga, In, Zr, Sb, Bi, Mg, Nb, Ta and Ti, a second metallic infrared reflective layer such as silver or aluminum, or mixtures thereof, ultimately doped with less than 15 wt.% platinum, palladium or gold, the second barrier layer, the top dielectric layer. Another further example of suitable IR coatings includes a solar control coating comprising a base dielectric layer comprising at least a base dielectric bottom layer and a base dielectric top layer whose composition differs from the composition of the base dielectric bottom layer, wherein the base dielectric top layer comprises any one of zinc oxide or a mixed oxide of Zn and at least one additional material X, wherein the X/Zn ratio in the base dielectric top layer is from 0.02 to 0.5 by weight, and wherein X is one or more materials selected from the group consisting of Sn, Al, Ga, In, Zr, Sb, Bi, Mg, Nb, Ta and Ti, a first metallic infrared reflecting layer such as silver or aluminum, or mixtures thereof, ultimately doped with less than 15 wt.% platinum, palladium or gold, a first barrier layer, a second dielectric layer comprising at least a second dielectric bottom layer and a second dielectric top layer whose composition differs on the composition of a second dielectric underlayer, wherein the second dielectric underlayer is in direct contact with the first barrier layer and the second dielectric top layer; the second dielectric top layer comprises any one of zinc oxide or a mixed oxide of Zn and at least one additional material Y, wherein the Y/Zn ratio in the second dielectric top layer is from 0.02 to 0.5 by weight, and wherein Y is one or more materials selected from the group consisting of Sn, Al, Ga, In, Zr, Sb, Bi, Mg, Nb, Ta and Ti, a second metallic infrared reflective layer such as silver or aluminum, or mixtures thereof, ultimately doped with less than 15 wt.% platinum, palladium or gold, the second barrier layer, a third dielectric layer comprising at least the third dielectric underlayer and a third dielectric top layer, the composition of which differs from the composition of the third dielectric

- 10 048106 a dielectric bottom layer, wherein the third dielectric bottom layer is in direct contact with the second barrier layer and the third dielectric top layer; the third dielectric top layer comprises any one of zinc oxide or a mixed oxide of Zn and at least one additional material Y, in which the Y/Zn ratio in the third dielectric top layer is from 0.02 to 0.5 by weight, and in which Y is one or more materials selected from the group consisting of Sn, Al, Ga, In, Zr, Sb, Bi, Mg, Nb, Ta and Ti, a third metallic infrared reflecting layer such as silver or aluminum, or mixtures thereof, ultimately doped with less than 15 wt.% platinum, palladium or gold, the third barrier layer, the top dielectric layer.

In such sets, the main dielectric top layer can be in direct contact with the first infrared reflecting layer. The central dielectric top layer can be in direct contact with the second infrared reflecting layer. The top layers of both the main dielectric layer and the central, first and second dielectric layers can independently have a geometric thickness within the range of from about 3 to 20 nm. One or both of the additional materials X and Y can be Sn and / or Al. The proportion of Zn in the mixed oxide forming the main dielectric top layer and / or forming the central dielectric top layer can be such that the X / Zn ratio and / or the Y / Zn ratio are from about 0.03 to 0.3 by weight. The first and / or second and / or third barrier layers can be a layer containing Ti and / or containing Ti oxide, and each of them can independently have a geometric thickness of 0.5 to 7 nm. The main dielectric top layer and/or the central and/or the second and/or the third dielectric top layers can independently have a geometric thickness of <20 nm, alternatively <15 nm, alternatively <13 nm, alternatively <11 nm and >3 nm, alternatively >5 nm, alternatively >10 nm. Each of the infrared reflecting layers can independently have a thickness of 2 to 22 nm, alternatively 5 to 20 nm, alternatively 8 to 18 nm. The upper dielectric layer can comprise at least one layer comprising a mixed oxide of Zn and at least one additional Ma material, in which the Ma/Zn ratio in this layer is from 0.02 to 2.0 by weight, and in which Ma is one or more materials selected from the group consisting of Sn, Al, Ga, In, Zr, Sb, Bi, Mg, Nb, Ta and Ti.

A specific example of such a solar control coating is shown in Table A below, in which ZnSnOx is a mixed oxide containing Zn and Sn deposited by reactive sputtering of a target that is an alloy or mixture of Zn and Sn, in the presence of oxygen. Alternatively, the mixed oxide layer can be formed by sputtering of a target that is a mixture of zinc oxide and an oxide of an additional material, in particular in argon gas or an argon-rich oxygen-containing atmosphere.

The Ti barriers are deposited by sputtering a Ti target in a pure argon or argon-rich oxygen-containing atmosphere to deposit a barrier that is not fully oxidized. The oxidation state of each of the base, core, and top dielectric ZnSnOx layers is not necessarily the same. Likewise, the oxidation state of each of the Ti barriers is not necessarily the same. Each overlying barrier protects the underlying silver layer from oxidation during sputter deposition of the overlying ZnSnOx oxide layer. And although the oxide layers overlying the barrier layers may be further oxidized during deposition, a portion of these barriers may remain in metallic form or in an oxide form that is not fully oxidized to provide a barrier for and during subsequent heat treatment of the glazing panel.

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Table A

(Sn/Zn ratio by weight) Geometrical thickness Glass substrate 1.1-3 mm The main dielectric layer contains: lower layer ZnSnOx (0.7) upper layer ZnSnOx (0.17) 15-30 nm 7-12 nm Ag 8-12 nm overlying Ti barrier 4-9 nm Central dielectric layer containing central bottom layer ZnSnOx (0.7) upper layer ZnSnOx (0.17) 60-70 nm 7-12 nm Ag 8-12 nm overlying barrier of Ti 4-9 nm Top dielectric layer containing: bottom layer ZnSnOx (0.17) top layer ZnSnOx (0.7) 6-9 nm 11-18 nm Protective surface coating made of Ti 2-8 nm

An optimal IR coating suitable for the present invention may comprise the following successive layers:

a main dielectric layer comprising a main dielectric bottom layer and a main dielectric top layer having a composition different from the composition of the main dielectric bottom layer, wherein the main dielectric bottom layer comprises a mixed oxide of Zn and Sn having an Sn/Zn ratio in the range of from 0.5 to 2 by weight, wherein the main dielectric top layer comprises a mixed oxide of Zn and Sn having an Sn/Zn ratio in the range of from 0.02 to 0.5 by weight, a first infrared reflective layer comprising metallic silver, a first barrier layer, a central dielectric layer comprising a central dielectric bottom layer and a central dielectric top layer having a composition different from the composition of the central dielectric bottom layer, which is in direct contact with the first barrier layer and contains a mixed oxide of Zn and Sn having an Sn/Zn ratio in the range of from 0.5 to 2, wherein the central dielectric top layer contains a mixed oxide of Zn and Sn having an Sn/Zn ratio in the range of from 0.02 to 0.5 by weight, a second infrared reflective layer containing metallic silver, a second barrier layer, an upper dielectric layer. Such an optimal IR coating suitable for the present invention may contain the following successive layers and have the following geometric thicknesses:

a main dielectric layer comprising a main dielectric bottom layer and a main dielectric top layer whose composition differs from the composition of the main dielectric bottom layer, wherein the main dielectric bottom layer comprises a mixed oxide of Zn and Sn having an Sn/Zn ratio in the range of from 0.5 to 2 by weight and has a geometric thickness of 15-25 nm, wherein the main dielectric top layer comprises a mixed oxide of Zn and Sn having an Sn/Zn ratio in the range of from 0.02 to 0.5 by weight and has a geometric thickness of 5-15 nm, a first infrared reflective layer comprising metallic silver having a geometric thickness of 8-16 nm, a first barrier layer having a geometric thickness of 3-8 nm, a central dielectric layer comprising a central dielectric bottom layer and a central dielectric top layer whose composition differs from the composition of the central dielectric bottom layer, which is in direct contact with the first barrier layer and

- 12 048106 contains a mixed oxide of Zn and Sn having a Sn/Zn ratio in the range of 0.5 to 2 and having a geometric thickness of 58-74 nm, wherein the central dielectric top layer contains a mixed oxide of Zn and Sn having a Sn/Zn ratio in the range of 0.02 to 0.5 by weight and has a geometric thickness of 5-15 nm, a second infrared reflective layer containing metallic silver having a geometric thickness of 8-16 nm, a second barrier layer having a geometric thickness of 3-8 nm, an upper dielectric layer having a geometric thickness of 14-22 nm, an optional surface coating having a geometric thickness of 2-8 nm.

An additional optimal IR coating suitable for the present invention may comprise the following successive layers:

a main dielectric layer comprising a main dielectric bottom layer and a main dielectric top layer whose composition differs from the composition of the main dielectric bottom layer, wherein the main dielectric bottom layer comprises a mixed oxide of Zn and Sn having an Sn/Zn ratio in the range of from 0.5 to 2 by weight, wherein the main dielectric top layer comprises a mixed oxide of Zn and Sn having an Sn/Zn ratio in the range of from 0.02 to 0.5 by weight, a first infrared reflective layer comprising metallic silver, a first barrier layer, a second dielectric layer comprising a second dielectric bottom layer and a second dielectric top layer whose composition differs from the composition of the second dielectric bottom layer, which is in direct contact with the first barrier layer and contains a mixed oxide of Zn and Sn having an Sn/Zn ratio in the range of from 0.5 to 2, wherein the second dielectric top layer contains a mixed oxide of Zn and Sn having an Sn/Zn ratio in the range of from 0.02 to 0.5 by weight by weight, a second infrared reflecting layer comprising metallic silver, a second barrier layer, a third dielectric layer comprising a third dielectric bottom layer and a third dielectric top layer, the composition of which differs from the composition of the third dielectric bottom layer, which is in direct contact with the second barrier layer and contains a mixed oxide of Zn and Sn having an Sn/Zn ratio in the range of from 0.5 to 2, wherein the third dielectric top layer contains a mixed oxide of Zn and Sn having an Sn/Zn ratio in the range of from 0.02 to 0.5 by weight, a third infrared reflecting layer comprising metallic silver, a third barrier layer, a top dielectric layer. Such an additional optimal IR coating suitable for the present invention may comprise the following successive layers and have the following geometric thicknesses:

a main dielectric layer comprising a main dielectric bottom layer and a main dielectric top layer whose composition differs from the composition of the main dielectric bottom layer, wherein the main dielectric bottom layer comprises a mixed oxide of Zn and Sn having an Sn/Zn ratio in the range of from 0.5 to 2 by weight and has a geometric thickness of 25-35 nm, wherein the main dielectric top layer comprises a mixed oxide of Zn and Sn having an Sn/Zn ratio in the range of from 0.02 to 0.5 by weight and has a geometric thickness of 5-15 nm, a first infrared reflective layer comprising metallic silver having a geometric thickness of 10-16 nm, a first barrier layer having a geometric thickness of 3-8 nm, a second dielectric layer comprising a second dielectric bottom layer and a second dielectric top layer whose composition differs from the composition of the second dielectric bottom layer, which is in direct contact with the first barrier layer and contains a mixed oxide of Zn and Sn having a Sn/Zn ratio in the range of from 0.5 to 2, and has a geometric thickness of 58-74 nm, wherein the second dielectric top layer comprises a mixed oxide of Zn and Sn, having a Sn/Zn ratio in the range of from 0.02 to 0.5 by weight, and has a geometric thickness of 5-15 nm, a second infrared reflective layer containing metallic silver, having a geometric thickness of 10-17 nm, a second barrier layer having a geometric thickness of 3-8 nm, a third dielectric layer comprising a third dielectric bottom layer and a third dielectric top layer, the composition of which differs from the composition of the third dielectric bottom layer, which is in direct contact with the second barrier layer and contains a mixed oxide of Zn and Sn, having a Sn/Zn ratio in the range of from 0.5 to 2, and has a geometric thickness of 50-75 nm, wherein the third dielectric top layer comprises a mixed oxide of Zn and Sn, having a Sn/Zn ratio in the range of 0.02 to 0.5 by weight, and has a geometric thickness of 5-15 nm, a third infrared reflective layer containing metallic silver, having a geometric thickness of 10-16 nm,

- 13 048106 a third barrier layer having a geometric thickness of 3-8 nm, an upper dielectric layer having a geometric thickness of 20-40 nm, an optional surface coating having a geometric thickness of 2-8 nm.

The deposition methods of the optional IR coating on the panel surface include chemical vapor deposition (CVD), plasma-enhanced chemical vapor deposition (PECVD), physical vapor deposition (PVD), magnetron sputtering, wet coating, etc. Different layers of the corresponding coatings can be deposited using different technical solutions.

The panel having IR coating can be subjected to heat treatment in accordance with the types of heat treatment described above.

When embedded in an intermediate layer, the IR coating may be deposited on a plastic substrate, wherein said plastic substrate is then inserted between the first surface of the inner panel and the second surface of the outer panel, inside the intermediate layer (with clamping by the material of the intermediate layer on both sides) or so that it is in contact with one of the first surface of the inner panel and the second surface of the outer panel on one side and in contact with the intermediate layer on the other side.

Examples of plastic substrates include poly(ethylene terephthalate) (PET), poly(butylene terephthalate), polyacrylates and methacrylates such as poly(methyl methacrylate) (PMMA), poly(methacrylate) and poly(ethyl acrylate), copolymers such as methyl methacrylate-ethyl acrylate copolymer, and polycarbonates in the form of thin sheets. The plastic substrates themselves are commercially available or can be made by various methods known in the art.

IR coatings on provided plastic substrates are generally known in the art and will not be described here. Some of them may be commercially available from at least Eastman or 3M.

In the context of the present invention, the inner panel provided with a reflective coating for p-polarized light may be subjected to heat treatment if said coating is capable of withstanding such heat treatment. In some cases, the inner panel provided with the first coating is subjected to heat treatment.

In some cases, it may be useful to mechanically strengthen the outer panel by heat treatment to increase its resistance to mechanical constraints. It may also be necessary to bend laminated glazing at high temperature for specific applications.

The multilayer glazing may be assembled in a layering step for flat substrates or may be a bending step for curved substrates, wherein said bending step comprises the following steps: first bending the panels, and then layering said curved panels. The present invention also provides a HUD system comprising:

1) a light source that projects p-polarized light towards the laminated glazing,

2) said multilayer glazing comprising an outer panel having a first surface and a second surface, and an inner panel having a first surface and a second surface, wherein both panels are bonded by at least one sheet of intermediate layer material that provides contact between the first surface of the inner panel and the second surface of the outer panel, wherein the inner panel is a coated substrate comprising a transparent substrate provided with a reflective coating for p-polarized light on its second surface, sequentially comprising, starting from the surface of the substrate:

a) optional:

i) a first coating comprising one or more layers with a high refractive index, the first coating having a thickness of from 1 to 100 nm, and ii) a second coating comprising one or more layers with a low refractive index, the second coating having a thickness of from 1 to 220 nm, and

b) a third coating consisting of one or more high refractive index layers, the third coating having a thickness of from 40 to 150 nm, and

c) a fourth coating consisting of one or more layers with a low refractive index, wherein the fourth coating has a thickness of from 40 to 200 nm, and further comprising at least one first layer of absorbing material, wherein said at least one first layer of absorbing material has a thickness of from 0.2 to 15 nm, and said absorbing material has an average refractive index n greater than 1 and an average extinction coefficient k greater than 0.1, wherein the average values of n and k are calculated based on values at wavelengths of 450 nm, 550 nm and 650 nm.

That is, a real HUD system contains:

1) a light source that projects p-polarized light towards the laminated glazing,

- 14 048106

2) a multilayer glazing as described above, wherein said multilayer glazing comprises a coated substrate as also described above.

That is, equivalently speaking, a real HUD system contains:

1) a light source that projects p-polarized light toward the laminated glazing, and

2) a multilayer glazing comprising at least two panels bonded together by at least one sheet of intermediate layer material, wherein at least one of the panels is a coated substrate as described above.

The light source typically provides for projection of light toward the glazing. The light source in the context of the present invention comprises a polarizer, so that the projected light is p-polarized light. Thus, in the context of the present invention, the light source provides p-polarized light. Such light allows for preferential reflection of the projected information toward the glazing.

Light sources providing p-polarized light are generally known in the art and will not be described herein.

Typically, the projected light falls on the glazing at an angle of 42° to 72° in the plane of incidence.

The advantage of the present HUD system provided by the p-polarized light source is that (Rp-pol) can reach 14% at the angle of incidence of said p-polarized light of 65°. The values of reflected p-polarized light can increase up to 16%, up to 18% or even up to 19% at the angle of 65°.

The present coated substrate can be useful in the case of transportation applications or construction applications where projection of images or light from a p-polarized light source can be used. Construction applications include displays, windows, doors, partitions, shower panels, etc. In the case of such construction applications, projection of a clear image can be useful for displaying room information, building information, entertainment information, or the like.

Applications in the transportation field include those vehicles that are used for transportation by road, air, sea and water, such as automobiles, buses, trains, ships, airplanes, spacecraft, space stations and other motor vehicles.

Thus, the present coated substrate may be a windshield, a rear window, a side window, a sunroof, a panoramic roof or any other window suitable for a car, or any glazing for any other transport device where the projection of a clear image may be useful. The projected and reflected information may include any traffic information, such as directions or traffic density; or any vehicle status information, such as speed, temperature; or entertainment information, or the like. The wide field of view allows for different viewing angles and is thus suitable for taller and shorter observers/drivers.

In some cases, when the IR coating is provided in a true multi-layer glazing, said multi-layer glazing may serve as heated glazing. Such heated glazing includes heated vehicle glazing or heated windshield.

In some embodiments compatible with other embodiments of the present invention, a second light source may be present in the HUD system and provide a secondary image or information. The second light source may not be polarized or may be p-polarized or s-polarized, but provide an image that is the same or different from the first light source. In some cases, the image or information differs between the first and second light sources. In some cases, the augmented reality information may be projected by at least one of the light sources due to a wide field of view and/or projection field.

In the context of the present invention, the presence of a reflective coating for p-polarized light on the glazing of a vehicle enables optimal light reflection for p-polarized light without increasing the overall reflectivity of the instrument panel to a level that is inconvenient for the driver.

The end use conditions assume that the coating is on the external surface of the glazing, exposed to the interior of the vehicle or building, which implies exposure to various types of cleaning agents, humidity, contamination and mechanical wear.

The present invention also provides the use of a coated substrate comprising a transparent substrate provided with a reflective coating for p-polarized light, sequentially comprising, starting from the surface of the substrate:

a) optional:

i) a first coating comprising one or more high refractive index layers, the first coating having a thickness of from 1 to 100 nm, and

- 15 048106 ii) a second coating consisting of one or more layers with a low refractive index, wherein the second coating has a thickness of from 1 to 220 nm, and

b) a third coating consisting of one or more high refractive index layers, the third coating having a thickness of from 40 to 150 nm, and

c) a fourth coating consisting of one or more layers with a low refractive index, wherein the fourth coating has a thickness of from 40 to 200 nm, and further comprising at least one first layer of absorbing material, wherein said at least one first layer of absorbing material has a thickness of from 0.2 to 15 nm, and said absorbing material has an average refractive index n higher than 1 and an average extinction coefficient k higher than 0.1, wherein the average values of n and k are calculated based on values at wavelengths of 450 nm, 550 nm and 650 nm; in a HUD system comprising a p-polarized light source that projects light at an incidence angle onto the glazing of from 42° to 72°, to reflect said p-polarized light.

The present coated substrate in the HUD system enables the proper functioning of the said HUD system, wherein the reflective coating for p-polarized light has a polarization enhancement factor (PEF) Rp-pol/Rv( _in ) that is at least 3% greater than the reflective coating for p-polarized light without any similar absorbing layer at an incidence angle of p-polarized light from 42° to 72°, alternatively at an angle of 65°, when the first, second, third and fourth coatings are present. This increase in the polarization enhancement factor (PEF) Rp-pol/Rv( _in ) is at least 6% when only the third and fourth coatings are present, alternatively at least 8%, alternatively at least 10% at an incidence angle of p-polarized light from 42° to 72°, alternatively at an angle of 65°.

Examples

Coated substrates comprising a transparent substrate provided with a reflective coating for p-polarized light were obtained or simulated using optical simulation software in the case of single-sheet glazing, and also installed in a multilayer form and evaluated for their optical parameters taking into account specific lighting conditions. The substrates were glass sheets. The types and thicknesses of said glass sheets, the characteristics of the coatings and the test conditions will be presented below. The light source is designed to emit normal light or p-polarized light. The behavior of the glazing with respect to incident light is presented in the following tables.

All optical parameters are given for illuminant D65, 2° for reflectance or transmittance levels and illuminant D65, 10° for color indices (a* and b*).

All refractive indices are measured at 550 nm unless otherwise stated.

In the examples provided, the clear glass was clear float glass used at 1.8mm thickness, except where one sheet of 4mm was specified.

The green glass was soda lime glass with _iron oxide in the form of _Fe2O3 in amounts ranging from 0.3 to 1.0 wt% and was used with a thickness of 1.8 mm.

Dielectric materials:

TZO: titanium oxide/zirconium oxide in a ratio of 55/45 wt.% with a refractive index of 2.19 (at 550 nm);

TrZO: titanium oxide/zirconium oxide in a ratio of 75/25 wt% (then Tr means high titanium content) with a refractive index of 2.33 (at 550 nm);

TiO ₂ : titanium oxide, refractive index 2.37 (at 550 nm);

TSO: titanium oxide/silicon oxide in a ratio of 92/8 wt.% with a refractive index of 2.17 (at 550 nm);

SiO ₂ : silicon oxide, exhibiting a refractive index of 1.46 (at 550 nm);

SiZrO: silicon oxide/zirconium oxide in a ratio of 65/35 wt.% with a refractive index of 1.57 (at 550 nm);

AZOx: substoichiometric zinc oxide/aluminium oxide in a ratio of 98/2 wt.% with a refractive index of 1.56 (at 550 nm);

SiN: Silicon aluminum nitride containing a silicon/aluminum ratio of 90/10 wt% and having a refractive index of 2.03 (at 550 nm).

Absorbing (ABS) materials:

Pd: palladium with 99.9% purity;

MCr: 80/20 wt% nickel-chromium double alloy;

NiCrW: ternary nickel-chromium-tungsten alloy with a Ni/Cr/W ratio of 40/10/50 wt%;

NiCrWN: ternary nickel-chromium-tungsten alloy nitride with a Ni/Cr/W ratio of 40/10/50 wt%;

Si: silicon with added aluminum, comprising a silicon/aluminum ratio of 90/10 wt%.

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Material of the metal infrared reflective layer:

Ag: silver with 99.9% purity.

The average refractive index n and the average extinction coefficient k for various absorbing materials and for silver are presented in Table 1. This average value is calculated from 3 wavelength values, namely at 450, 550 and 650 nm. An average refractive index n < 1 indicates a material that is not suitable as an absorbing material. Thus, silver, gold, copper, aluminum, having an average value n < 1, are not suitable as an absorbing material within the framework of the present invention.

Table 1

Materials Average value η Average value to Pd 3.13 1.73 NiCr 2.50 3.70 NiCrW 3.34 3.84 NiCrWN 2.56 2.20 Si 3.95 1,16 Ag 0.09 3.52

The parameters measured relative to external reflection (Rv( _out )) were as follows:

a) light source A, 2°:

Tv (%) represents the transmittance in the visible range;

Rv( _out ) (%) represents the external reflectance in the visible range at a standard incidence angle of 8°;

Rv(in) (%) represents the internal reflectance in the visible range for total light at an incidence angle of 65°, also referred to as R115( _in ) if the incidence angle is measured from the opposite side of the glazing (i.e. 180° - 65°), also referred to as total reflectance in the following examples;

Rp_pol (%) represents the internal reflectance of p-polarized light in the visible range and at an incidence angle of 65°, also designated as Rp_pol 115° if the incidence angle is measured from the opposite side of the glazing (i.e. 180°-65°);

R172( _in ) (%) represents the internal reflectance in the visible range at a standard incidence angle of 8° (or 172° if it refers to the outer surface of the glazing);

Abs172 (%) represents absorption and is equal to 100% - Tv (%) - R172( _in ) (%);

PEF represents the polarization enhancement factor and is equal to Rp_pol (%)/Rv( _in ) (%);

b) light source D65, 10°:

a* Rout represents the color index a* of the external reflectance at 8°;

b* Rout represents the color index b* of the external reflectance at 8°;

a*_R _in represents a* R115 and represents the color index of a* internal reflectance at 115°;

b*_R _in represents b* R115 and represents the color index b* of internal reflectance at 115°;

a*_R _p _poi represents a* R115p_pol and represents the color index a* of internal reflectance at 115° for p-polarized light;

b*_R _p _p _o i represents b* R115p_pol and represents the color index b* of internal reflectance at 115° for p-polarized light;

a* R172 represents the color index a* of internal reflectance at 172°;

b* R172 represents the color index b* of internal reflectance at 172°.

The results generally show that the visible light transmittance - Tv (%) > 70%;

systematic improvement of the internal reflection optical properties with Rp-pol at 65° up to levels of 14 or 16% or even 18% or 19%, while the internal reflection (Rv(in)) remained at the same levels as the corresponding comparative examples;

non-conductivity of the reflective coating for p-polarized light with a surface resistance >100 ohms/square. All reflective coatings for p-polarized light had emissivity values >0.5.

These results indicate the suitability of the actual vehicle glazing for the claimed HUD system.

- 17 048106

Examples 1 and 2, comparative example 1.

Examples 1 and 2 and Comparative Example 1 were prepared and the coatings were deposited on one sheet of 4 mm transparent glass as indicated in Table 2.

The Si absorber material was sputtered from a target in an argon atmosphere. A small part of the material is oxidized during the subsequent sputtering of the silicon oxide layer and the subsequent heat treatment for windshield bending (670°C for 10 min in a furnace with a static or dynamic temperature). It was proven that in order to provide the necessary p-polarization enhancement function, the silicon layer remains in an unoxidized form, acting as an absorber material as defined in this document, as also evidenced by the increased absorption value (Abs172 (%)).

The values for the parameters are given in Table 3.

Table 2

Thickness (nm) TZO TrZO SiO2 ABS SiO2 Glass Comparative example 1 38.7 30.3 115.9 Example 1 38.7 30.3 2.5 (Si) 121.9 Example 2 38.7 30.3 10 2.5 (Si) 121.9

Table 3

Comparative Example 1 Example 1 Example 2 Tv (%) 84.3 77.8 76.5 Rv(out) (%) 12.9 9.8 And,2 a* Rout -7.5 -6.8 -9.4 b* Rout -15.9 -4.4 -3.7 R172(in) (%) 13.1 13.8 14.4 Rv(in) (%) 20.2 20.4 19.4 a* RI 72 -7.3 -6.1 -8.2 b* R172 -16.6 -15.8 -11.0 a*_Rin 3.9 4.6 1,3 b*_Rin -9.5 -8.5 -9.4 Rppol (%) 14.9 17,5 16.3 a*_Rp_pol -4.8 -4.3 -3.5 b*_Rp_pol 6.8 4.9 9.0 Absl72 (%) 2.6 8.4 9.2 PEF 0,740 0,856 0,843 PEF (%) 74.0 85.6 84.3 Difference in PEF vs CE1 (%) I,6 10.3

The values indicate that the p-polarized light reflective coatings of Examples 1 and 2 were more effective in reflecting p-polarized light while providing acceptable overall reflectivity (Rv( _in )), with a p-polarization enhancement factor of more than 80%. This demonstrated an improvement of more than 8% compared to the p-polarized light reflective coating without an ABS layer according to Comparative Example 1.

The absorption also increased from a value of approximately 2% for comparative example 1 to values above 8% for examples 1 and 2, which is due to the ABS silicon layer.

Examples 1 and 2 and comparative example 1 had a surface resistance > 200 ohms/square.

Examples 3 and 4, comparative examples 2 and 3.

Examples 3 and 4 and Comparative Example 2 were a multilayer version of the assemblies of Examples 1 and 2 deposited on a 1.8 mm thick sheet of clear float glass.

Thus, multi-layer glazing containing a sheet of green float was provided.

- 18 048106 1.8 mm glass on which is laminated a 0.76 mm PVB interlayer, for a sheet of transparent float glass 1.8 mm, having a reflective coating for p-polarized light, so that the coating is located in the direction of the inside (P4) of the vehicle. The designs of the coatings are similar to those provided in Table 2 above.

Comparative Example 2 was a laminated glazing comprising a 1.8 mm green float glass sheet laminated with a 0.76 mm PVB interlayer over a 1.8 mm clear float glass sheet having the coating of Comparative Example 1.

Comparative Example 3 was a laminated glazing comprising a 1.8 mm green float glass sheet laminated with a 0.76 mm PVB interlayer over a 1.8 mm clear float glass sheet with no coating.

The values for the parameters are given in Table 4.

__________________________________________________________________________ Table 4

Comparative example 3 Comparative example 2 Example rz Example p4 Tv (%) 83.8 79,0 72.8 71.6 Rv(out) (%) 7.5 I,9 9.1 10.4 a* Rout -1.5 -9.2 -7.7 -10.3 b* Rout 0,0 -13.5 -3.4 -2.7 R172(in) (%) 7.5 12.7 13.5 14,0 Rv(in) (%) 19.2 18.6 19,0 17.9 a* RI 72 -1.5 -8.1 -6.7 -8.8 b* R172 oh,oh -16.8 -16.1 -I,2 a*_Rin -1.9 z,o 3.9 0,1 b*_Rin 0,4 -10.2 -9.4 -10.6 Rp_pol (%) 2,5 14.8 17.3 16.2 a*_Rp_pol -1,2 -5.0 -4.5 -3.7 b*_Rp_pol 0.8 7.0 5.0 9.1 Absl72 (%) 8.7 8.3 13.7 14.4 PEF 0,131 0,796 0.913 0.903 PEF (%) 13.1 79.6 91.3 90.3 PEF Retail vs CE2 (%) And,7 10.7

The values indicate that the p-polarized light reflective coatings of Examples 3 and 4 were more effective in reflecting p-polarized light while providing acceptable overall reflectivity (Rv(in)), with a p-polarization enhancement factor of more than 90%. This demonstrated an improvement of more than 10% compared to the p-polarized light reflective coating without an ABS layer according to Comparative Example 2.

The absorption also increased from a value of approximately 8% for comparative example 2 to values above 13% for examples 3 and 4, which is due to the ABS silicon layer.

Examples 3 and 4 and comparative example 2 had surface resistance >200 ohms/square.

Examples 5-7 and comparative example 4.

Examples 5-7 with silicon as the absorbing material and comparative example 4 were simulated examples in accordance with examples 3 and 4 above.

Laminated glazings were simulated comprising a 1.8 mm green float glass sheet laminated with a 0.76 mm PVB interlayer over a 1.8 mm clear float glass sheet having a reflective coating for p-polarized light so that the coating was located towards the inside (P4) of the vehicle. The coating designs are provided in Table 5.

The values for the parameters are given in Table 6.

- 19 048106

Table 5

Thickness (nm) TΪΟ2 SiO2 ABS TZO SiO2 Glass Comparative example 4 65 123.5 Example 5 63.7 2 (Si) 123.5 Example 6 63.7 5 2 (Si) 117.5 Example 7 50 1,3 (Si) 13.7 125,0

Table 6

Comparative example 4 Example 5 Example 6 Example 7 Tv (%) 79.9 74.7 75.6 74.4 Rv(out) (%) IL 8,8 8.4 9.0 a* Rout -8.7 -7.4 -6.8 -5.7 b* Rout -16.7 -8.9 -10.7 -8.9 R172(in) (%) And,7 12.3 And,1 12.2 Rv(in) (%) 17.6 17.9 17.8 18.6 a* RI 72 -7.6 -6.6 -6.1 -5.1 b* R172 -20.5 -20.1 -19.4 -22.1 a*_Rin 3.5 4.6 4.9 6.2 b*_Rin -I,5 -I,2 -9.1 -9.9 Rp_pol (%) 13.1 15.2 14.7 15.8 a*_Rp_pol -5.2 -5.0 -5.0 -5.4 b*_Rp_pol 6.0 3.8 3.5 z,z Absl72 (%) 8.4 13,0 13.3 13.4 PEF 0,744 0,851 0,831 0.853 PEF (%) 74.4 85.1 83.1 85.3 Difference in PEF vs CE4 (%) 10.7 8.7 10.9

The values indicate that the p-polarized light reflective coatings of Examples 57 were more effective in reflecting p-polarized light while providing acceptable overall reflectivity (Rv(in)), with a p-polarization enhancement factor of more than 80%. This demonstrated an improvement of more than 8% compared to the p-polarized light reflective coating without an ABS layer according to Comparative Example 4.

The absorption also increased from approximately 8% for the comparative example to values above 13% for examples 5-7, which is due to the ABS silicon layer.

Examples 5-7 and comparative example 4 had surface resistance >200 Ohm/square.

Examples 8-10, comparative examples 5 and 6.

Multilayer glazings were provided comprising a sheet of green float glass of 1.8 mm on which was laminated a PVB interlayer of 0.76 mm, for a sheet of clear float glass of 1.8 mm, having a reflective coating for p-polarized light, so that the coating was located in the direction of the inside (P4) of the vehicle. The designs of the coatings are provided in Table 7, with the thicknesses of the corresponding layers indicated in nm.

Examples 8-10 were simulated with palladium as the absorbing material, each having an additional oxide layer successively deposited on said palladium layer. In examples 8 and 9, the subsequent layer was a layer of a material with a high refractive index (TZO and TiO ₂ , respectively), so that ABS was thus inserted inside the third coating layer having a high refractive index. In example 10, the subsequent layer was a layer of a material with a low refractive index (AZOx), so that ABS was inserted between the third and fourth coatings.

Comparison example 5 did not contain any ABS layer.

Comparative Example 6 contained a silver layer followed by a TiO2 layer such that the silver layer was embedded within the third coating layer having a high refractive index.

- 20 048106

The values for the parameters are given in Table 8.

Table 7

Thickness (nm) TZO ABS Ag TZO TiO2 AZ Ox _SiO2 Comparative example 5 70.7 124.4 Example 8 65.7 2 (Pd) 5 124.4 Example 9 63 2 (Pd) 5 124.4 Example 10 65.7 2 (Pd) 5 121.1 Comparative example 6 63 2(Ag) 5 124.4

Table 8

Comparative example 5 Example 8 Example 9 Example p 10 Comparative example 6 Tv (%) 78.8 71,5 71.6 71.3 77.4 Rv(out) (%) 12,0 9.5 9.0 9.2 12.7 a* Rout -10.5 -9.9 -8.7 -9.0 -I,4 b* Rout -12.8 -10.0 -10.4 -I,7 -13.9 R172(in) (%) 12.8 13.9 14,0 14,0 13.9 Rv(in) (%) 17,5 17.4 17.4 17.3 16.9 a* RI 72 -9.6 -9.2 -8.9 -8.6 -10.4 b* R172 -15.9 -14.3 -15.9 -17.5 -17.1 a*_Rin 1,6 1,7 2,3 2.6 o,z b*_Rin -12.0 -12.1 -12.6 -13.1 -14.0 Rp_pol (%) 13.2 15.4 15,5 15.4 12.5 a*_Rp_pol -4.7 -4.2 -4.4 -4.4 -5.0 b*_Rp_pol 10,5 10.9 9.7 8.7 9.4 Absl72 (%) 8.4 14.6 14.4 14.7 8.7 PEF 0.758 0,886 0,889 0,887 0,738 PEF (%) 75.8 88.6 88.9 88.7 73.8 Difference in PEF vs CE5 (%) 12.8 13.1 12.9 - 1.5

The values indicate that the p-polarized light reflective coatings of Examples 810 were more effective at reflecting p-polarized light while still providing acceptable overall reflectivity (Rv( _in )), with a p-polarization enhancement factor of greater than 88%. This demonstrated an improvement of greater than 12% over the p-polarized light reflective coating without the ABS layer of Comparative Example 5. Comparative Example 6 demonstrated a reduction in the p-polarization enhancement factor compared to Comparative Example 5, since the presence of silver actually reduced the reflection of p-polarized light.

The absorption also increased from a value of approximately 8% for comparative example 5 to values above 14% for examples 8-10, which is due to the ABS layer of palladium, regardless of its position within the coating. The silver layer does not have a significant effect on the absorption in comparative example 6 compared to comparative example 5 (from a value of 8.4% to a value of 8.7%).

Examples 8-10 and Comparative Example 5 had a surface resistance of >200 ohms/square, while Comparative Example 6 had a surface resistance of 40 ohms/square.

Examples 11-14, comparative example 7.

Laminated glazings were provided comprising a sheet of 1.8 mm green float glass laminated with a 0.76 mm PVB interlayer for a sheet of 1.8 mm clear float glass having a reflective coating for p-polarized light such that the coating was arranged in

- 21 048106 towards the inside (P4) of the vehicle. The coating designs are provided in Table 9, with the thicknesses of the corresponding layers indicated in nm.

Examples 11-14 were simulated with NiCr, NiCrW or NiCrWN as the absorber material, each being sandwiched between silicon nitride layers, while in example 14 only one silicon nitride layer was deposited on top of the ABS layer. Example 14 comprised a fourth coating with a SiO2 sublayer covered by a SiZrO sublayer, both being low refractive index materials (n<1.7). Thus, in examples 11-14, ABS is embedded within a third coating layer having a high refractive index, comprising a TZO layer and a SiN layer(s).

The values for the parameters are given in Table 10.

Table 9

Thickness (nm) TZO SiN ABS SiN _SiO2 SiZrO Comparative example 7 56.9 20 117.6 Example 11 63.6 10 1.3 (NiCr) 10 106.4 Example 12 61 10 1,1 (NiCrW) 10 109.5 Example 13 59.2 10 2.6 (NiCrWN) 10 110.5 Example 14 59.2 2.0 (NiCrWN) 20 51.5 55,0

Table 10

Comparative example 7 Example 11 Example 12 Example 13 Example 14 Tv (%) 81.6 72.3 71.1 70.7 72.9 Rv(out) (%) 9.2 8.2 7,8 7.6 7.6 a* Rout -8.0 -8.8 -8.3 -8.1 -7.3 b* Rout -10.9 -I,5 -11.0 -10.3 -9.7 R172(in) (%) 9.5 And,5 12,0 12.2 11.8 Rv(in) (%) 17,5 17.2 17.2 17,0 16,5 a* RI 72 -7.8 -7.9 -8.0 -8.2 -8.8 b* R172 -13.6 -13.1 -14.1 -14.5 -15.4 a*_Rin 3.8 3.8 3.7 3.6 3.2 b*_Rin -6.3 -7.7 -8.8 -9.5 -10.7 Rp_pol (%) 12.7 15.3 15.6 15.4 14.1 a*_Rp_pol -4.6 -4.1 -4.3 -4.3 -4.4 b*_Rp_pol 12.2 12.2 10.7 10.6 And,7 Absl72 (%) 8,8 16.2 16.9 17.1 15.3 PEF 0.723 0,887 0.908 0.906 0.854 PEF (%) 72.3 88.7 90.8 90.6 85.4 PEF difference vs CE7 (%) 16.4 18,5 18.3 13.1

The values indicate that the p-polarized light reflective coatings of Examples 11-14 were more effective in reflecting p-polarized light while providing acceptable overall reflectivity (Rv(in)), with a p-polarization enhancement factor of more than 85%. This demonstrated an improvement of more than 13% compared to the p-polarized light reflective coating without an ABS layer according to Comparative Example 7.

The absorption also increased from approximately 8% for comparative example 7.

- 22 048106 up to values above 15% for examples 11-14, which is due to the ABS layer containing nickel-chromium.

Examples 11-14 and comparative example 7 had a surface resistance of > 200 ohms/square. Example 14 has the additional benefit of improved chemical resistance due to the SiZrO top layer compared to the other examples and comparative examples.

Examples 15 and 16, comparative examples 8 and 9.

Multilayer glazings were provided comprising a sheet of green float glass of 1.8 mm on which was laminated a PVB interlayer of 0.76 mm, for a sheet of clear float glass of 1.8 mm, having a reflective coating for p-polarized light, so that the coating was located in the direction of the inside (P4) of the vehicle. The designs of the coatings are provided in Table 11, with the thicknesses of the corresponding layers indicated in nm.

Comparative Examples 8 and 9 were reproductions of examples according to the pending PCT application PCT/EP2O2O/O86578 for reflective coatings for p-polarized light which do not contain any ABS layers.

Examples 15 and 16 were developed based on comparative examples 8 and 9, respectively, such that the coatings contained a layer of absorbent material, namely palladium, inserted between the third and fourth coating layers.

The values for the parameters are given in Table 12.

Table 11

Thickness (nm) TZO ABS SiO2 Comparative example 8 64.6 100.9 Example 15 64.6 3.8 (Pd) 100.9 Comparative example 9 64.8 113.1 Example 16 64.8 3.2 (Pd) 113.1

Table 12

Comparative example 8 Example 15 Comparative example 9 Example 16 Tv (%) 83.7 70.4 82.2 70.7 Rv(out) (%) 7,7 5.5 9.0 6.5 a* Rout 2.0 3.2 -4.2 -z,o b* Rout -15.9 -14.4 -18.4 -15.0 R172(in) (%) 7,8 9.8 9.2 from Rv(in) (%) 21,1 21.7 18.7 18.8 a* RI 72 3.8 2.6 -2.9 -3.5 b* R172 -19.6 -16.3 -22.5 -19.7 a*_Rin 4.0 5,6 5.3 6.5

- 23 048106

b*_Rin 4.9 6.0 -4.9 -5.6 Rp_pol (%) I,9 16.4 12.7 16,5 a*_Rp_pol -5.5 -4.7 -5.5 -4.7 b*_Rp_pol -2.3 -0.4 1,9 z,z Ab si 72 (%) 8.6 19.8 8.6 18.1 PEF 0.564 0.754 0,680 0,879 PEF (%) 56.4 75.4 68,0 87.9 Difference in PEF compared to CE8 or CE9 respectively (%) 19,0 19.8

The values indicate that the p-polarized light reflective coatings according to Examples 15 and 16 were more effective in reflecting p-polarized light while providing acceptable total reflectivity (Rv( _in )), with the p-polarization enhancement factor being greater than 75%. This demonstrated an improvement of 19% or more compared to the p-polarized light reflective coating without an ABS layer according to its respective comparative examples 8 and 9.

The absorption also increased from approximately 8% for comparative examples 8 and 9 to values above 18% for examples 15 and 16, which is due to the ABS palladium layer.

Examples 15 and 16 and comparative examples 8 and 9 had surface resistance >200 ohms/square.

Examples 17 and 18, comparative example 10.

Multilayer glazings were provided comprising a sheet of green float glass of 1.8 mm on which was laminated a PVB interlayer of 0.76 mm, for a sheet of clear float glass of 1.8 mm, having a reflective coating for p-polarized light, so that the coating was located in the direction of the inside (P4) of the vehicle. The designs of the coatings are provided in Table 13, with the thicknesses of the corresponding layers indicated in nm.

Comparative Example 10 was a reproduction of Example 12 according to the pending PCT application PCT/EP2O2O/O86578 for reflective coatings for p-polarized light, which does not contain any ABS layers.

Examples 17 and 18 were developed on the basis of comparative example 10, so that the coatings contained a layer of absorbent material, namely palladium. In example 17, the ABS layer was inserted inside the third coating, while in example 18 it was inserted between the third and fourth coatings.

The values for the parameters are given in Table 14.

Table 13

Thickness (nm) TrZO SiO2 TSO ABS TSO SiO2 Comparative example 10 11,2 157.7 64.1 123.2 Example 17 11,2 157.7 30,0 0.6 (Pd) 34.1 123.2 Example 18 11,2 157.7 64.1 0.9 (Pd) 123.2

- 24 048106

Table 14

Comparative example 10 Example 17 Example 18 Tv (%) 73.4 70.8 70.6 Rv(out) (%) 17,0 16.6 15.6 a* Rout -17.5 -16.5 -17.4 b* Rout 3,3 4.6 4.8 R172(in) (%) 18.8 18.8 19.3 Rv(in) (%) 22.6 21,1 22.7 a* R172 -17.0 -17.5 -15.8 b* R172 2.6 z,o 3.5 a*_Rin 3.1 3.1 2,2 b*_Rin -14.6 -16.2 -13.9 Rp_pol (%) 17.4 17.2 18,5 a*_Rp_pol -13.2 -12.7 -12.7 b*_Rp_pol 8.2 9.3 9.4 Ab si 72 (%) 7,8 10.4 Yu,1 PEF 0,770 0,812 0.814 PEF (%) 77,0 81.2 81.4 Difference PEF vs. CEU (%) 4.1 4,4

The values indicate that the p-polarized light reflective coatings of Examples 17 and 18 were more effective in reflecting p-polarized light while providing acceptable overall reflectivity (Rv( _in )), with a p-polarization enhancement factor of more than 80%. This represents an improvement of 4% or more compared to the p-polarized light reflective coating without an ABS layer according to Comparative Example 10.

The absorption also increased from 7.8% for comparative example 10 to values above 10% for examples 17 and 18, which is due to the ABS palladium layer.

Examples 17 and 18 and comparative example 10 had a surface resistance of >200 ohms/square.

Examples 19 and 20 and comparative examples 11 and 12.

Multilayer glazings were provided comprising a sheet of green float glass of 1.8 mm on which was laminated a PVB interlayer of 0.76 mm, for a sheet of clear float glass of 1.8 mm, having a reflective coating for p-polarized light, so that the coating was located in the direction of the inside (P4) of the vehicle. The designs of the coatings are provided in Table 15, with the thicknesses of the corresponding layers indicated in nm.

Examples 19 and 20 were developed based on comparative examples 11 and 12 respectively, so that the coatings contained a layer of absorbent material, namely palladium. In these examples, an ABS layer was inserted between the third and fourth coatings.

The values for the parameters are given in Table 16.

Table 15

Thickness (nm) TZO S1O2 TZO ABS S1O2 Comparative example 11 7 129 69 98 Example 19 7 129 69 3.2 (Pd) 98

- 25 048106

Comparative example 12 6 197 65 114 Example 20 6 197 65 3.2 (Pd) 114

Table 16

Comparative example 11 Example 19 Comparative example 12 Example 20 Tv (%) 80.2 70.2 81.7 70.3 Rv(out) (%) 10.9 8.0 9.4 6.8 a* Rout -1.8 -0.6 -0.5 -0.5 b* Rout -I,2 -13.9 -16.0 -12.1 R172(in) (%) And,5 13,0 9.8 And,5 Rv(in) (%) 24.2 24.9 20.2 20.6 a* RI 72 0,2 -0.8 1,6 2,4 b* R172 -13.9 -6.6 -20.0 -20.0 a*_Rin 4,5 4.7 5.3 5.8 b*_Rin 4.1 6,6 -3.0 -2.1 Rppol (%) 13.2 17,0 14.9 18,5 a*_Rp_pol -8.2 -7.4 -6.8 -5.2 b*_Rp_pol -4.5 -1.3 10.4 10.7 Absl72 (%) 8.3 16.8 8.5 18.2 PEF 0,545 0,681 0,735 0.899 PEF (%) 54.5 68.1 73.5 89.9 Difference in PEF compared to CE11 or CE 12 respectively (%) 13.6 16.4

The values indicate that the p-polarized light reflective coatings of Examples 19 and 20 were more effective in reflecting p-polarized light than their corresponding comparative examples 11 and 12, respectively, while providing a similar or lower total reflectance (Rv( _in )), with a p-polarization enhancement factor of more than 68% and a p-polarization reflectance of 17% or more. This demonstrates an increase of 13% or more in the p-polarization enhancement factor compared to the p-polarized light reflective coating without the ABS layer according to the corresponding comparative examples.

The absorption also increased to values greater than or equal to 16% for examples 19 and 20, which is due to the ABS palladium layer.

Examples 19 and 20, as well as their corresponding comparative example 11 and 12, had a surface resistance of >100 ohms/square.

Example 21, comparative example 13.

Multilayer glazings were provided comprising a sheet of clear float glass of 1.8 mm on which was laminated a PVB interlayer of 0.76 mm, for the sheet of clear float glass of 1.8 mm having a reflective coating for p-polarized light, so that the coating was located in the direction of the inside (P4) of the vehicle. The designs of the coatings are provided in Table 17, with the thicknesses of the corresponding layers indicated in nm.

Comparative Example 13 was a further reproduction of Example 12 according to the pending PCT application PCT/EP2O2O/O86578 for reflective coatings for p-polarized light, which does not contain any ABS layers.

Example 21 was developed based on comparative example 13, so that the coatings contained a layer of absorbent material, namely palladium. In example 21, an ABS layer was inserted between the third and fourth coatings.

The values for the parameters are given in Table 18.

- 26 048106

Table 17

Thickness (nm) TrZO SiO2 TSO ABS SiO2 Comparative example 13 11,2 157.7 64.1 123.2 Example 21 11,2 157.7 64.1 2.6 (Pd) 123.2

Table 18

Comparative example 13 Example 21 Tv (%) 78.7 70.3 Rv(out) (%) 18.6 14.5 a* Rout -16.5 -16.4 b* Rout 2.8 6,7 R172(in) (%) 19.1 20.6 Rv(in) (%) 24,0 24.2 a* RI 72 -16.2 -13.0 b* R172 2,4 4.2 a*_Rin 3,4 1,0 b*_Rin -13.4 -11.5 Rp_pol (%) 17,5 20,5 a*_Rp_pol -12.9 -11.6 b*_Rp_pol 8.1 from Ab si 72 (%) 2,2 9.1 PEF 0,730 0,847 PEF (%) 73,0 84.7 Difference in PEF vs CE13 (%) I,8

The values indicate that the p-polarized light reflective coatings of Example 21 were more effective in reflecting p-polarized light while still providing acceptable overall reflectivity (Rv( _in )), with a p-polarization enhancement factor of 84.7%. This represents an 11.8% improvement over the p-polarized light reflective coating without an ABS layer of Comparative Example 13.

The absorption also increased from 2.2% for Comparative Example 13 to 9.1% for Example 21, which is due to the ABS palladium layer.

Example 21 and comparative example 13 had a surface resistance of >100 ohms/square.

Thus, the previous examples represent a coated substrate comprising a transparent substrate provided with a reflective coating for p-polarized light that exhibits the necessary properties for a polarization enhancement factor (PEF is the ratio Rppol'Rv _(lli:i ) that make it suitable for use in a HUD system projecting p-polarized light onto a windshield comprising said coated substrate such that the p-polarized light is incident on the coated side of the coated substrate and is thus reflected therefrom.

An IR reflective coating comprising at least 2 metallic silver layers and 3 dielectric layers could be deposited on the first surface of the inner panel (S3), but is not shown in the present examples. Other options could include metallic IR reflective films on PET within the PVB interlayer.

Asymmetrical laminated structures can be provided within the scope of the present invention if the two sheets of glass have different thicknesses. This can be provided, for example, by a sheet of glass of 2.1 mm, on which a sheet of glass of 1.1 to 1.5 mm or even ultra-thin glass of 0.5 to 1 mm is laminated. Examples are also covered in which a sheet of blue or grey glass can be laminated on a sheet of transparent glass.

Claims (17)

1. A transparent substrate with a reflective coating for p-polarized light, sequentially containing, starting from the surface of the substrate: a) a coating consisting of one or more layers of a high refractive index material having a thickness of from 40 to 150 nm (referred to as the third coating), and b) a coating consisting of one or more layers of a low refractive index material having a thickness of from 40 to 200 nm (referred to as a fourth coating), and further comprising at least one first layer of absorbing material, wherein said at least one first layer of absorbing material has a thickness of from 0.2 to 15 nm, and said absorbing material has an average refractive index n greater than 1 and an average extinction coefficient k greater than 0.1, wherein the average values of n and k are calculated based on values at wavelengths of 450, 550 and 650 nm. 2. The substrate according to claim 1, wherein the reflective coating for p-polarized light further comprises in series between the substrate and the third coating, starting from the surface of the substrate: a) optional: i) a first coating consisting of one or more layers of high refractive index materials, the first coating having a thickness of from 1 to 100 nm, and ii) a second coating consisting of one or more layers of low refractive index material, the second coating having a thickness of from 1 to 220 nm. 3. The substrate according to claim 1, wherein the material with a high refractive index of the third coating is selected from at least one of the oxides of Zn, Sn, Ti, Nb, Zr, Ni, In, Al, Si, Ce, W, Mo, Sb and Bi and mixtures thereof or nitrides of Si, Al, Zr, B, Y, Ce and La and mixtures thereof. 4. The substrate according to claim 2, wherein the high refractive index material of the first coating and the third coating is independently selected from at least one of oxides of Zn, Sn, Ti, Nb, Zr, Ni, In, Al, Si, Ce, W, Mo, Sb and Bi and mixtures thereof or nitrides of Si, Al, Zr, B, Y, Ce and La and mixtures thereof. 5. The substrate according to claim 1, wherein the material with a high refractive index of the third coating is selected from an oxide of Zr, Nb, Sn, Zn or Ti; mixed oxide of two or more of Ti, Zr, Nb, Si, Sb, Sn, Zn, In; nitride of Si, Zr, Al, B; mixed nitride of two or more of Si, Zr, Al, B. 6. The substrate according to claim 2, wherein the high refractive index material of the first coating and the third coating is independently selected from an oxide of Zr, Nb, Sn, Zn or Ti; mixed oxide of two or more of Ti, Zr, Nb, Si, Sb, Sn, Zn, In; nitride of Si, Zr, Al, B; mixed nitride of two or more of Si, Zr, Al, B. 7. The substrate according to claim 1, 3 or 5, wherein the material with a low refractive index of the fourth coating is selected from silicon oxide, silicon oxynitride, silicon oxycarbide, aluminum oxide, mixed silicon and aluminum oxide, mixed silicon and zirconium oxide, aluminum-doped zinc oxide or mixtures thereof. 8. The substrate according to claim 2, 4 or 6, wherein the high refractive index material of the second coating and the fourth coating is independently selected from silicon oxide, silicon oxynitride, silicon oxycarbide, aluminum oxide, mixed silicon-aluminum oxide, mixed silicon-zirconium oxide, aluminum-doped zinc oxide or mixtures thereof. 9. A substrate according to any one of the preceding claims, wherein at least one layer of absorbent material is selected from NiCr, W, Nb, Zr, Ta, Pd, Si, Ti or alloys based on Ni and/or Cr and/or W, or alloys based on Cr and Zr or based on W and Zr or Cr, or based on W and Ta, optionally including an additional element selected from Ti, Nb, Ta, Ni and Sn; or from TiN, CrN, WN, NbN, TaN, ZrN, NiCrN or NiCrWN, or a mixture of these nitrides. 10. A substrate according to any of the preceding claims, wherein at least one layer of absorbent material is provided with at least one barrier layer. 11. The substrate according to claim 2, characterized in that at least one first layer of absorbent material: (a) either inserted between at least two adjacent coverings of said first, second, third or fourth coverings; or b) is inserted inside at least one of said first, second, third or fourth coatings. 12. A substrate according to any of the preceding paragraphs, characterized in that it further comprises a second layer of absorbent material, different from the first layer of absorbent material, wherein the second layer of absorbent material: - 28 048106 a) either inserted between two adjacent layers of dielectric of at least one of the said first, second, third or fourth coatings; or b) inserted within at least one of said first, second, third or fourth coverings, wherein the location of the second layer of absorbent material is different from the location of the first layer of absorbent material. 13. Multilayer glazing comprising an outer panel having a first surface and a second surface, and an inner panel having a first surface and a second surface, wherein both panels are bonded by at least one sheet of intermediate layer material, which ensures contact between the first surface of the inner panel and the second surface of the outer panel, wherein the inner panel is a substrate according to one of claims 1, 2. 14. Multilayer glazing according to claim 13, further comprising a reflective coating for infrared radiation, comprising n layers based on a reflective functional layer for IR radiation and n+1 dielectric layers, wherein each layer based on a reflective functional layer for IR radiation is located between two dielectric layers, located on at least one of the first surface of the inner panel or the second surface of the outer panel or built into the intermediate layer. 15. A HUD system comprising a light source projecting p-polarized light towards the multilayer glazing according to one of claims 13, 14. 16. The HUD system according to claim 15, wherein the projected light falls on the glazing at an angle of 42 to 72°. 17. Use of a substrate according to one of claims 1 to 12 in a HUD system comprising a p-polarized light source that projects light at an incidence angle of 42 to 72° onto the glazing to reflect said p-polarized light.