Title of Invention	"REFLECTIVE ARTICLE AND A PROCESS FOR PREPARING THE SAME"
Abstract	Reflective article comprising a substrate (10), a titanium dioxide-based photocatalytic layer (40) disposed on the front face of the reflective article and a reflective layer (20) disposed between the photocatalytic layer and the substrate or disposed on the rear face of the substrate, said article being characterized in that reflective layer (20) is composed of an oxidized or nitride metal in an under-stoichiometic state such that the total light reflection integrated over the entire visible range of the composite article is in the range of between 40 and 75%.

Title of Invention

"REFLECTIVE ARTICLE AND A PROCESS FOR PREPARING THE SAME"

Abstract

Reflective article comprising a substrate (10), a titanium dioxide-based photocatalytic layer (40) disposed on the front face of the reflective article and a reflective layer (20) disposed between the photocatalytic layer and the substrate or disposed on the rear face of the substrate, said article being characterized in that reflective layer (20) is composed of an oxidized or nitride metal in an under-stoichiometic state such that the total light reflection integrated over the entire visible range of the composite article is in the range of between 40 and 75%.

Full Text	The present invention relates to reflective article. The present invention relates to a reflective articsie, in particular for the rear-view mirrors for motor vehicles, having hydrophilic properties and an attenuated reflection factor. The present invention also relates to a process, for the production of, such an article. Mirrors comprising a metal layer (generally made of silver, aluminium or chromium) applied either to- the rear face of a transparent substrate, i.e. pn the face remote from the observer, or on the front face of the substrate, thus the face directed towards the observer, are known. With a metal layer of chromium having a thickness In the order of 40 to 60 nm, a light reflection of about 65% Is obtained, which is perfectly satisfactory for use as a rear-view mirror. However, with mpre significant light reflections the rear-view mirror has the disadvantage of .causing glare for the driver. Mirrors with a surface, which has been rendered hydrop.hil.ic, are also known (see EP 689 962, EP 1 022 588 or JP 20.01033607, for example) The hydrophilic character, -of a surface increases its surface energy,, which allows drops of water to spread in a film instead of forming droplets; On a non-hydrophilic mirror the rain forms droplets, whichrqbstruct visibility; On a mirrqr with a hydrophilic surface, the water spreads to form a film to allow better visibility. Various materials are known for their inherent hydrophilic properties, , in particular titanium oxide and silicon oxide, In addition to Its hydrophilic properties, titanium oxlde, particularly when crystallised in the form of anatase, is also well known ,for its inherent photocatalytic properties, i,e, it is able to degrade organic matter when stimulated by light or UV irradiation. Patent applications EP 978 494 and EP 1 099 671 describe anti-fog mirrors comprising a reflective metal film respectively on the rear and front face and a TiO2/SlO2 coating stack on the front face. Since the Ti02 layer has a high refractive index (n-2.4), the reflection factor of the coating stack in the visible range is elevated, in the order to 80% for a stack of neutral colouration. To reduce glare, the thicknesses of the layers must be selected so that the wavelength of the reflected light has a peak between 400 and 510 nm, which gives a reflected blue colour and a light refection in the order of 60%. EP 1 099 671 provides that a reflection-adjusting layer can be added between the reflective film and the T102 layer to prevent excessive reduction of the light reflection. Coating stacks with alternating layers of high and low refractive index are commonly used to increase the light reflection. Documents EP 456 488 and EP 1 040 963 describe mirrors with high light reflection (>70%) using a metal layer as reflective layer, and a succession of low index layers (SiO2) and high index layers (TiO2) to increase reflection. There is a need to provide a reflective article with a photocatalytic and hydrophiiic effect to allow good visibility in the case of rain, white rnaintalning a moderate reflection factor to decrease glare. It must be possible in a simple manner to provide such an article with moderate reflection in neutral reflected- tones as well as in coloured tons, e.g. in the blue range. The aim of the invention is to remedy the disadvantage described above. In particular, an aim of the present invention is to provide a retkcttvs article, which has hydrophiiic and photocatalytic properties, and a light reflection, which !s maintained at a level of reflection that is not excessive evcn with a neutral colouration. The subject of the present invention is a composite article comprising a substrate, a reflective iayer (generally referred to as reflector) composed of an oxidised or nitrided metal, possibly in an under-stoichifpmetrie state, possibly covered by a barrier layer, then a titanium dioxide-based layer with photocatalytic properties, then possibly a fine porous hydrophiiic layer composed in particular of silicon oxide. This surface layer can be discontinuous. In particular, the reflective layer is a Cr,Ny wherein x is comprised between 0.67 and 0.9, preferably between 0.7-0.8 and y is comprised between 0.1-0,33, preferably between 0.2-0.3. Accordinq to an advantageous embodiment shown in Figure 1, ihe layers are disposed on the same face of (the substrate. However, jt is al$o possible to dispose the reflective layer on the rear face, i.e. on the face remote from the observer., and the photocatalytic layer on the front face, as shown In Figure 2, The thickness of the photocatalytic layer can be in the range of between 20 and 120 nm and preferably between 40 and 75 nm. This thickness of the surface layer is itself generally in ihe range of between 2 and 10 nm and preferably between 3 and 8 nm. This latter layer allows the hydropnilic character of the surface to be preserved for longer after the light irradiation has ceased. The very fine thickness of this outer layer enables the photocatalytic effect of the TiO2 layer to be preserved to some extent. When a barrier layer is disposed between the reflective layer and the photocatalytic layer, this barrier layer is advantageously composed of silicon oxide. Its thickness can lie between 10 and 80 nm and preferably between 20 and 60 nm, As n result of this barrier layer, the migration of alkaline constituents of the glass, in particular Na+ ions, towards the titanium oxide layer can be reduced or prevented, and also the titanium oxide layer can be separated from the reflector. The metal of the reflective layer can be selected from titanium, chromium, aluminium, silicon, zirconium and alloys of these metals. Advantageously, the reflective layer is composed of partially oxidised or nitrlded chromium. Its thickness can lie between 20 and 150 nrn, preferably between 40 and 120 nm. It is advantageous if the above-described reflective article has a light reflection (integrated over the entire visible range} in the range of between 40 and 75% and preferably between 45 and 70% of the incident visible light. When the reflected colour of the article according to the invention is neutral (i.e. when the coefficients a* and b* of the Lab system lie between -5 and 5), it is advantageous if the reflection factor lies between 55 and 75%, preferably between 60 and 70%, and when the reflected colour is within the blue range (i,e. a* lies between -10 and 0 and b* is less than -10}, it is advantageous if the refaction factor lies between 40 and 55%, preferably between 40 and 50%. The coefficients a* and b* are measured with the illuminant D65 at an angle of incidence of 2°. The light transmission of the article must be very low and preferably less than 3%, indeed less than 2%. Thf present invention also relates to a process for the production of a reflective and hydrophilic article, which comprises the following steps; the deposit of a lightly oxidised or nitrided metal layer (20) on the front or rear face of a support by catliodtc magnetron sputtering In a controlled reactive atmosphere with a metal target; possibly the deposit of an SiO2 barriei layer on the front face of the support by cathodic magnetron sputtering in a reactive atmosphere with ar, Si target; the deposit of o TiO2K layer on the front face by cathodic magnetron sputtering, e.g. in a reactive atmosphere with a Ti target; thermal treatment at a temperature in the range of between 300 and 500"C, in particular between 350 and 450°C, for a period that may vary from 15 minutes to 6 hour.', in particular from 30 minutes to 4 hours, which allows the TiO2 to crystallise in the form of anatase while preventing crazing of. the TiO2 and the haze which would result therefrom. In particular, a process according to the invention also comprises a Step of depositing a fine surface layer of SiO2, by magnetron sputtering in a reactive atmosphere with an Si target. When the reflective layer is disposed on the rear face, this is advantageously deposited first. The barrier and photocatalytic layers and the surface layer are then deposited on the opposite face. The entire covered substrate can then be subjected to a thermal treatment. The present invention is described below by non-restrictive practical examples. Example 1: A coating slack comprising glass / CrxOy/ SiCX, / TlO2 / SlO2 of neutral colouration, as shown in Figure 1, is formed on a clear soda-lime glass (10) with a thickness of 2 rnrn by cathodic magnetron sputtering. The conditions of depositing the different layers forming the stack are as follows: A first layer (20) of lightly oxidised chromium is deposited on the substrate (10) from a chromium rneta! target in an atmosphere of 80% by mass of argon and 20% by mass of oxygen. The thickness of the layer is in the order of 45 nrn. A barrier layer (30) of SiO2, is deposited on the first layer from an Si metal target in an atmosphere of 75% by mass of argon and 25% by mass of oxygen. The thickness of the layer is in the order of 40 nrn. A layer of TiO2 (40) is deposited on the barrier layer from tin oxidised titanium target in an atmosphere of 75% by mass of argon and 25% by mass of oxygen. The thickness of the layer is in the order of 60 nm. A last very fine layer of SiO2(50) is then deposited on the coaling stack. The deposit is performed from an Si metal target in an atmosphere of 75% by mass of argon and 25% by mass of oxygen. The thickness of the layer is. in the order of 5 nm. The coated substrate is then subjected to a thermal treatment for 1 hour at 400°C. The rise in temperature occurs rapidly but cooling is conducted very progressively (approximately 3°C per minute). The light reflection factor (LR) integrated over the entire visible range is measured in accordance with the standard SAE J 964 with an integrating photometer. The substrate coated according to Example 1 has a LR or 05%, while the sam« stack of S1O2 / Ti02 / SiO2 on a chromium metal layer of the same thickness would have given a LR of 80% and would therefore have given too much glare for use as a rear-view mirror (see Figure 3). The reflected colour of the coating stack Is determined by the colorimetric coordinates L, a, b* on the basts of illuminant D65 with an angle of incidence of 2°. The values obtained are collated in the table below. The very low values for a* and b* show that the coating stack does not have any significant reflected colour. The light transmission (L.T; integrated over the visible range is 0.0%. Exitmpie 2: A coating stack comprising glass / CxNy / Si02 / TiO2 / SiO2 uf blue colouration, as also shown in Figure 1, is formed on a clear soda-lirne glass (10) with a thickness of 2 mm by cathodic magnetron sputtering. The conditions of depositing the different layers forming the stack are as follows: A first layer (20) of lightly nitridcd chromium is deposited an the substrate from a chromium metal target in an atmosphere of 50% by mass of argon and 50% by mass of nitrogen. The thickness of the layer is in the order of 45 nm. A barrier layer (30) of SiO2 with a thickness in the order of 25 nm, then a TiO2 layer (40) with a thickness in the order of 40 nm, and then a last layer of SiO2 (50) with a thickness in the order of 5 nm are successively deposited in the same conditions as described in Example 1. The coated substrate is then subjected to a thermal treatment under the same conditions as described in Example 1. The light reflection factor (LR) integrated over the entire, visible range Is measured in accordance with the standard SAE J 964 with an integrating photometer. The substrate coated according to Example 2 has a LR of 43%, while the same coating stack of Si02 / TiO2 / Si02 on a chromium metal layer of the same thickness would have given a LR of 56% (see Figure 4). The reflected colour of the coating stack is determined by the colorimetric coordinates L, a, b* on the basis of illurninant D65. The values obtained are collared in the table below. The negative values for b* and the very slightly negative values for a* show that the coating stack has a slightly greenish reflected blue colour. The- light transmission (LT) integrated over the visible range is 1,5%. Exnmple 3 : A coating stack comprising glass / CrNy / SiOj, / TlOa / SiO2;, of neutral colour, as also shown in Figure. 1, is formed on a clear soda-lime glass (10) with a thickness of 2 rnm by cathodic magnetron sputtering in the same conditions as in example 2. The thickness of the layers are : 75 nm for the CiNy layer (20), 55 nm for the SiO2 barrier layer (30), 50 nm for the TiO2 layer (40) and around 5 nm for the SIO:, top layer (50). Tha coated substrate is then subjected to a thermal treatment under the same conditions as described in Example 1. Thin level of nirriclation of the CrxNy layer has been analysed. The index x is evaluated at 0.7 and y at 0.3. The substrate coated according to Example 3 has a LR of 68%, while the same coating stack of SiO., / TiCX / SlO2 on a chromium metal layer of the same thickness would have given a LR of 76% (see Figure 5), The colorirnetric coordinates L,' 3, b* of the reflected colour are collated in the table below. The very low values for a* and b* show that the coating stack does not have any significant reflected colour. (Table Removed) WE CLAIM: 1. Reflective article comprising a substrate (10), a titanium dioxide-basec photocatalytic layer (40) disposed on the front face of the reflective article and a reflective layer (20) disposed between the photocatalytic layer and the substrate or disposed on the rear face of the substrate, said article being characterized in that reflective layer (20) is composed of an oxidized or nitride metal in an under-stoichiometic state such that the total light reflection integrated over the entire visible range of the composite article is in the range of between 40 and 75%. 2. Article as claimed in claim 1, wherein the layers are disposed on the same face of the substrate. 3. Article as claimed in claim 1, wherein the reflective layer (20) is disposed on the rear face and the photocatalytic layer (40) on the front face. 4. Article as claimed in any one of the preceding claims, wherein it comprises a barrier layer (30) between the photocatalytic layer (40) and the substrate (10). 5. Article as claimed in the preceding claim, wherein the barrier layer (30) is composed of silicon oxide. 6. Article as claimed in any one of the preceding claims, wherein the metal of the reflective layer (20) is selected from Cr, Ti, Al, Si, Zr and the alloys of these metals. 7. Article as claimed in any one of the preceding claims, wherein it comprises a surface layer (50) on the front face. 8. Article as claimed in the preceding claim, wherein the surface layer (50) is composed of silicon oxide. 9. Article as claimed in any one of the preceding claims, wherein the thickness of the reflective layer (20) is in the range, of between 20 and l00nm and preferably between 30 and 60 nm. 10. Article as claimed in any one of the preceding claims, wherein the thickness of the photocatalytic layer (40) is in the range of between 20 and 120 nm and preferably between 40 and 75 nm. 11. Article as claimed in any one of the preceding claims, wherein that the thickness of the surface layer (50) is in the range of between 2 and 10 nm and preferably between 3 and 6 nm. 12. Article as claimed in any one of the preceding claims, wherein the thickness of the barrier layer (30) is in the range of between 10 and 80 nm and preferably between 20 and 60 nm. 13. Article as claimed in any one of the preceding claims, wherein the light reflection integrated over the entire visible range lies between 45 and 70%.

Full Text

The present invention relates to reflective article.
The present invention relates to a reflective articsie, in particular for the
rear-view mirrors for motor vehicles, having hydrophilic properties and an attenuated
reflection factor. The present invention also relates to a process, for the production of,
such an article.
Mirrors comprising a metal layer (generally made of silver, aluminium or chromium) applied either to- the rear face of a transparent substrate, i.e. pn the face remote from the observer, or on the front face of the substrate, thus the face directed towards the observer, are known. With a metal layer of chromium having a thickness In the order of 40 to 60 nm, a light reflection of about 65% Is obtained, which is perfectly satisfactory for use as a rear-view mirror. However, with mpre significant light reflections the rear-view mirror has the disadvantage of .causing glare for the driver.
Mirrors with a surface, which has been rendered hydrop.hil.ic, are also known (see EP 689 962, EP 1 022 588 or JP 20.01033607, for example)
The hydrophilic character, -of a surface increases its surface energy,, which allows drops of water to spread in a film instead of forming droplets; On a
non-hydrophilic mirror the rain forms droplets, whichrqbstruct visibility; On a mirrqr
with a hydrophilic surface, the water spreads to form a film to allow better visibility. Various materials are known for their inherent hydrophilic properties, , in particular titanium oxide and silicon oxide,
In addition to Its hydrophilic properties, titanium oxlde, particularly when crystallised in the form of anatase, is also well known ,for its inherent photocatalytic properties, i,e, it is able to degrade organic matter when stimulated by light or UV irradiation.
Patent applications EP 978 494 and EP 1 099 671 describe anti-fog mirrors comprising a reflective metal film respectively on the rear and front face and
a TiO2/SlO2 coating stack on the front face.

Since the Ti02 layer has a high refractive index (n-2.4), the reflection factor of the coating stack in the visible range is elevated, in the order to 80% for a stack of neutral colouration. To reduce glare, the thicknesses of the layers must be selected so that the wavelength of the reflected light has a peak between 400 and 510 nm, which gives a reflected blue colour and a light refection in the order of 60%. EP 1 099 671 provides that a reflection-adjusting layer can be added between the reflective film and the T102 layer to prevent excessive reduction of the light reflection.
Coating stacks with alternating layers of high and low refractive index are commonly used to increase the light reflection. Documents EP 456 488 and EP 1 040 963 describe mirrors with high light reflection (>70%) using a metal layer as reflective layer, and a succession of low index layers (SiO2) and high index layers (TiO2) to increase reflection.
There is a need to provide a reflective article with a photocatalytic and hydrophiiic effect to allow good visibility in the case of rain, white rnaintalning a moderate reflection factor to decrease glare. It must be possible in a simple manner to provide such an article with moderate reflection in neutral reflected- tones as well as in coloured tons, e.g. in the blue range.
The aim of the invention is to remedy the disadvantage described above. In particular, an aim of the present invention is to provide a retkcttvs article, which has hydrophiiic and photocatalytic properties, and a light reflection, which !s maintained at a level of reflection that is not excessive evcn with a neutral colouration.
The subject of the present invention is a composite article comprising a substrate, a reflective iayer (generally referred to as reflector) composed of an oxidised or nitrided metal, possibly in an under-stoichifpmetrie state, possibly covered by a barrier layer, then a titanium dioxide-based layer with photocatalytic properties, then possibly a fine porous hydrophiiic layer composed in particular of silicon oxide. This surface layer can be discontinuous.

In particular, the reflective layer is a Cr,Ny wherein x is comprised between 0.67 and 0.9, preferably between 0.7-0.8 and y is comprised between 0.1-0,33, preferably between 0.2-0.3.
Accordinq to an advantageous embodiment shown in Figure 1, ihe layers are disposed on the same face of (the substrate. However, jt is al$o possible to dispose the reflective layer on the rear face, i.e. on the face remote from the observer., and the photocatalytic layer on the front face, as shown In Figure 2,
The thickness of the photocatalytic layer can be in the range of between 20 and 120 nm and preferably between 40 and 75 nm. This thickness of the surface layer is itself generally in ihe range of between 2 and 10 nm and preferably between 3 and 8 nm. This latter layer allows the hydropnilic character of the surface to be preserved for longer after the light irradiation has ceased. The very fine thickness of this outer layer enables the photocatalytic effect of the TiO2 layer to be preserved to some extent.
When a barrier layer is disposed between the reflective layer and the photocatalytic layer, this barrier layer is advantageously composed of silicon oxide. Its thickness can lie between 10 and 80 nm and preferably between 20 and 60 nm, As n result of this barrier layer, the migration of alkaline constituents of the glass, in particular Na+ ions, towards the titanium oxide layer can be reduced or prevented, and also the titanium oxide layer can be separated from the reflector.
The metal of the reflective layer can be selected from titanium, chromium, aluminium, silicon, zirconium and alloys of these metals. Advantageously, the reflective layer is composed of partially oxidised or nitrlded chromium. Its thickness can lie between 20 and 150 nrn, preferably between 40 and 120 nm.
It is advantageous if the above-described reflective article has a light reflection (integrated over the entire visible range} in the range of between 40 and 75% and preferably between 45 and 70% of the incident visible light.
When the reflected colour of the article according to the invention is neutral (i.e. when the coefficients a* and b* of the Lab system lie between -5 and 5), it is advantageous if the reflection factor lies between 55 and 75%, preferably

between 60 and 70%, and when the reflected colour is within the blue range (i,e. a* lies between -10 and 0 and b* is less than -10}, it is advantageous if the refaction factor lies between 40 and 55%, preferably between 40 and 50%. The coefficients a* and b* are measured with the illuminant D65 at an angle of incidence of 2°.
The light transmission of the article must be very low and preferably less than 3%, indeed less than 2%.
Thf present invention also relates to a process for the production of a reflective and hydrophilic article, which comprises the following steps;
the deposit of a lightly oxidised or nitrided metal layer (20) on the front or rear face of a support by catliodtc magnetron sputtering In a controlled reactive atmosphere with a metal target;
possibly the deposit of an SiO2 barriei layer on the front face of the support by cathodic magnetron sputtering in a reactive atmosphere with ar, Si target;
the deposit of o TiO2K layer on the front face by cathodic magnetron sputtering, e.g. in a reactive atmosphere with a Ti target;
thermal treatment at a temperature in the range of between 300 and 500"C, in particular between 350 and 450°C, for a period that may vary from 15 minutes to 6 hour.', in particular from 30 minutes to 4 hours, which allows the TiO2 to crystallise in the form of anatase while preventing crazing of. the TiO2 and the haze which would result therefrom.
In particular, a process according to the invention also comprises a Step of depositing a fine surface layer of SiO2, by magnetron sputtering in a reactive atmosphere with an Si target.
When the reflective layer is disposed on the rear face, this is advantageously deposited first. The barrier and photocatalytic layers and the surface layer are then deposited on the opposite face. The entire covered substrate can then be subjected to a thermal treatment.
The present invention is described below by non-restrictive practical examples.
Example 1:

A coating slack comprising glass / CrxOy/ SiCX, / TlO2 / SlO2 of neutral colouration, as shown in Figure 1, is formed on a clear soda-lime glass (10) with a thickness of 2 rnrn by cathodic magnetron sputtering.
The conditions of depositing the different layers forming the stack are as follows:
A first layer (20) of lightly oxidised chromium is deposited on the substrate (10) from a chromium rneta! target in an atmosphere of 80% by mass of argon and 20% by mass of oxygen. The thickness of the layer is in the order of 45 nrn.
A barrier layer (30) of SiO2, is deposited on the first layer from an Si metal target in an atmosphere of 75% by mass of argon and 25% by mass of oxygen. The thickness of the layer is in the order of 40 nrn.
A layer of TiO2 (40) is deposited on the barrier layer from tin oxidised titanium target in an atmosphere of 75% by mass of argon and 25% by mass of oxygen. The thickness of the layer is in the order of 60 nm.
A last very fine layer of SiO2(50) is then deposited on the coaling stack. The deposit is performed from an Si metal target in an atmosphere of 75% by mass of argon and 25% by mass of oxygen. The thickness of the layer is. in the order of 5 nm.
The coated substrate is then subjected to a thermal treatment for 1 hour at 400°C. The rise in temperature occurs rapidly but cooling is conducted very progressively (approximately 3°C per minute).
The light reflection factor (LR) integrated over the entire visible range is measured in accordance with the standard SAE J 964 with an integrating photometer. The substrate coated according to Example 1 has a LR or 05%, while the sam« stack of S1O2 / Ti02 / SiO2 on a chromium metal layer of the same thickness would have given a LR of 80% and would therefore have given too much glare for use as a rear-view mirror (see Figure 3).
The reflected colour of the coating stack Is determined by the colorimetric coordinates L*, a*, b* on the basts of illuminant D65 with an angle of incidence of 2°. The values obtained are collated in the table below. The very low

values for a* and b* show that the coating stack does not have any significant reflected colour.
The light transmission (L.T; integrated over the visible range is 0.0%.
Exitmpie 2:
A coating stack comprising glass / CxNy / Si02 / TiO2 / SiO2 uf blue colouration, as also shown in Figure 1, is formed on a clear soda-lirne glass (10) with a thickness of 2 mm by cathodic magnetron sputtering.
The conditions of depositing the different layers forming the stack are as follows:
A first layer (20) of lightly nitridcd chromium is deposited an the substrate from a chromium metal target in an atmosphere of 50% by mass of argon and 50% by mass of nitrogen. The thickness of the layer is in the order of 45 nm.
A barrier layer (30) of SiO2 with a thickness in the order of 25 nm, then a TiO2 layer (40) with a thickness in the order of 40 nm, and then a last layer of SiO2 (50) with a thickness in the order of 5 nm are successively deposited in the same conditions as described in Example 1.
The coated substrate is then subjected to a thermal treatment under the same conditions as described in Example 1.
The light reflection factor (LR) integrated over the entire, visible range Is measured in accordance with the standard SAE J 964 with an integrating photometer. The substrate coated according to Example 2 has a LR of 43%, while the same coating stack of Si02 / TiO2 / Si02 on a chromium metal layer of the same thickness would have given a LR of 56% (see Figure 4).
The reflected colour of the coating stack is determined by the colorimetric coordinates L*, a*, b* on the basis of illurninant D65. The values obtained are collared in the table below. The negative values for b* and the very slightly negative values for a* show that the coating stack has a slightly greenish reflected blue colour.
The- light transmission (LT) integrated over the visible range is 1,5%.

Exnmple 3 :
A coating stack comprising glass / CrNy / SiOj, / TlOa / SiO2;, of neutral colour, as also shown in Figure. 1, is formed on a clear soda-lime glass (10) with a thickness of 2 rnm by cathodic magnetron sputtering in the same conditions as in example 2.
The thickness of the layers are : 75 nm for the CiNy layer (20), 55 nm for the SiO2 barrier layer (30), 50 nm for the TiO2 layer (40) and around 5 nm for the SIO:, top layer (50).
Tha coated substrate is then subjected to a thermal treatment under the same conditions as described in Example 1.
Thin level of nirriclation of the CrxNy layer has been analysed. The index x is evaluated at 0.7 and y at 0.3.
The substrate coated according to Example 3 has a LR of 68%, while the same coating stack of SiO., / TiCX / SlO2 on a chromium metal layer of the same thickness would have given a LR of 76% (see Figure 5),
The colorirnetric coordinates L*,' 3*, b* of the reflected colour are collated in the table below. The very low values for a* and b* show that the coating stack does not have any significant reflected colour.
(Table Removed)

WE CLAIM:
1. Reflective article comprising a substrate (10), a titanium dioxide-basec
photocatalytic layer (40) disposed on the front face of the reflective
article and a reflective layer (20) disposed between the photocatalytic
layer and the substrate or disposed on the rear face of the substrate,
said article being characterized in that reflective layer (20) is
composed of an oxidized or nitride metal in an under-stoichiometic
state such that the total light reflection integrated over the entire
visible range of the composite article is in the range of between 40 and
75%.
2. Article as claimed in claim 1, wherein the layers are disposed on the
same face of the substrate.
3. Article as claimed in claim 1, wherein the reflective layer (20) is
disposed on the rear face and the photocatalytic layer (40) on the front
face.
4. Article as claimed in any one of the preceding claims, wherein it
comprises a barrier layer (30) between the photocatalytic layer (40)
and the substrate (10).
5. Article as claimed in the preceding claim, wherein the barrier layer
(30) is composed of silicon oxide.
6. Article as claimed in any one of the preceding claims, wherein the
metal of the reflective layer (20) is selected from Cr, Ti, Al,
Si, Zr and the alloys of these metals.
7. Article as claimed in any one of the preceding claims, wherein it
comprises a surface layer (50) on the front face.
8. Article as claimed in the preceding claim, wherein the surface layer
(50) is composed of silicon oxide.
9. Article as claimed in any one of the preceding claims, wherein the
thickness of the reflective layer (20) is in the range, of between 20 and
l00nm and preferably between 30 and 60 nm.
10. Article as claimed in any one of the preceding claims, wherein the
thickness of the photocatalytic layer (40) is in the range of
between 20 and 120 nm and preferably between 40 and 75 nm.
11. Article as claimed in any one of the preceding claims, wherein that
the thickness of the surface layer (50) is in the range of between 2 and
10 nm and preferably between 3 and 6 nm.
12. Article as claimed in any one of the preceding claims, wherein the
thickness of the barrier layer (30) is in the range of between
10 and 80 nm and preferably between 20 and 60 nm.
13. Article as claimed in any one of the preceding claims, wherein the light
reflection integrated over the entire visible range lies between 45 and
70%.

Documents:

588-DELNP-2005-Abstract-(15-07-2008).pdf

588-DELNP-2005-Abstract-(30-06-2008).pdf

588-delnp-2005-abstract.pdf

588-DELNP-2005-Claims-(15-07-2008).pdf

588-DELNP-2005-Claims-(30-06-2008).pdf

588-delnp-2005-claims.pdf

588-delnp-2005-correspondence others.pdf

588-DELNP-2005-Correspondence-Others-(10-07-2008).pdf

588-DELNP-2005-Correspondence-Others-(30-06-2008).pdf

588-delnp-2005-description (complete)-15-07-2008.pdf

588-delnp-2005-description (complete)-30-06-2008.pdf

588-delnp-2005-description (complete).pdf

588-DELNP-2005-Drawings-(30-06-2008).pdf

588-delnp-2005-drawings.pdf

588-DELNP-2005-Form-1-(10-07-2008).pdf

588-DELNP-2005-Form-1-(15-07-2008).pdf

588-DELNP-2005-Form-1-(30-06-2008).pdf

588-delnp-2005-form-1.pdf

588-delnp-2005-form-18.pdf

588-DELNP-2005-Form-2-(15-07-2008).pdf

588-DELNP-2005-Form-2-(30-06-2008).pdf

588-delnp-2005-form-2.pdf

588-DELNP-2005-Form-3-(30-06-2008).pdf

588-delnp-2005-form-3.pdf

588-delnp-2005-form-5.pdf

588-delnp-2005-form-gpa.pdf

588-delnp-2005-form-pct-101.pdf

588-delnp-2005-form-pct-210.pdf

588-delnp-2005-form-pct-220.pdf

588-delnp-2005-form-pct-409.pdf

588-DELNP-2005-GPA-(30-06-2008).pdf

588-DELNP-2005-Others-Document-(10-07-2008).pdf

588-DELNP-2005-Others-Document-(14-07-2008).pdf

588-DELNP-2005-Petition-137-(30-06-2008).pdf

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Patent Number

222074

Indian Patent Application Number

588/DELNP/2005

PG Journal Number

32/2008

Publication Date

08-Aug-2008

Grant Date

17-Jul-2008

Date of Filing

16-Feb-2005

Name of Patentee

AGC FLAT GLASS EUROPE SA

Applicant Address

CHAUSSEE DE LA HULPE, 166, B-1170 BRUXELLES (WATERMAEL-BOITSFORT), BELGIUM.

Inventors:

#	Inventor's Name	Inventor's Address
1	LAURENT AUMERCIER	51 RUE DU MOULIN, F-57635 BROUVILLER, FRANCE
2	PIERRE-ANDRE DREIDEMY	31, RUE DE VERDUN, F-57200 REMELFING, FRANCE

PCT International Classification Number

G02B 1/11

PCT International Application Number

PCT/EP2003/050692

PCT International Filing date

2003-10-06

PCT Conventions:

#	PCT Application Number	Date of Convention	Priority Country
1	02/12820	2002-10-10	France