Title of Invention

GLAZING ASSEMBLY PROVIDED WITH A THIN FILM MULTILAYER THAT REFLECTS INFRARED RADIATION AND/OR SOLAR RADIATION

Abstract A glazing assembly comprising at least one transparent substrates, especially made of glass, provided with a thin-film multiplayer comprising, in the following order starting from the substrate, at least: (a) a first dielectric layer comprising a barrier layer acting as a barrier to the diffusion of oxygen and chosen from silicon nitrides; (b) a lower stabilizing layer made of a metal or metal alloy X such as herein described; (c) a functional layer having reflection properties in the infrared and/or in the solar radiation, especially a metal layer such as herein described; (d) an upper metal blocking layer made of metal or metal alloy Y such as herein described; (e) a second dielectric layer comprising a barrier layer acting as a barrier to the diffusion of oxygenand chosen from silicon nitrides; and (f) optionally, a protective oxide layer; in which multiplayer the metal or alloy X of the lower stabilizing layer is different from the metal or alby Y of the upper blocking layer; in which multiplayer the metal or alby X of the bwer stabilizing layer is different from the metal or alby Y of the upper blocking layer.
Full Text GLAZING ASSEMBLY PROVIDED WITH A THIN-FILM MULTILAYER
THAT REFLECTS INFRARED RADIATION AND/OR SOLAR RADIATION
The invention relates to transparent substrates, preferably rigid substrates
of the glass type, which are provided with thin-film multilayers that include at least
one layer of metallic behavior that can act on solar radiation and/or long-
wavelength infrared radiation for the purpose of forming glazing assemblies.
The invention relates to multilayers, comprising alternations of silver-based
layers and layers made of a transparent dielectric material of the oxide or metal or
nitride compound type, allowing the glazing assemblies to have solar-protection or
low-emissivity properties (double glazing for buildings, laminated windshields for
vehicles, etc.). It relates more particularly to glass substrates that are provided
with such multilayers and have to undergo conversion operations involving a heat
treatment at 500°C or higher: these may especially be a toughening treatment, an
annealing treatment or a bending treatment.
Rather than deposit the layers on the glass after its heat treatment (which
poses problems that increase the manufacturing costs), it was firstly sought to
adapt the multilayers so that they are able to undergo such treatments while still
maintaining most of their thermal properties. The object was therefore to prevent
the functional layers, especially the silver layers, from deteriorating. One solution,
disclosed in patent EP-506 507, consists in protecting the silver layers by flanking
them with metal layers for protecting the silver layers adjacent the dielectric oxide
layers. This therefore is a bendable or toughable multilayer insofar as it is just as
effective in reflecting infrared or solar radiation after the bending treatment or
toughening treatment as before said treatment. However, oxidation and
modification of the layers that have protected the silver layers from the effect of
heat, result in the optical properties of the multilayer being substantially modified,
especially resulting in an increase in light transmission and a change in the
colorimetric response in reflection. Furthermore, this heating also tends to create
optical defects, namely pits and/or various small impairments resulting in a
significant level of haze (the expression "small impairments" is generally
understood to mean defects having a size of less than 5 microns, whereas "pits"
are understood to mean defects larger in size than 50 microns, especially between
50 and 100 microns, with the possibility, of course, of also having defects of
intermediate size, i.e. between 5 and 50 microns).
Secondly, it was therefore attempted to develop such thin-film multilayers
that are capable of preserving both their thermal properties and their optical
properties after heat treatment, while still minimizing the appearance of optical
defects. The challenge was thus to produce thin-film multilayers of fixed
optical/thermal properties, whether or not they are to undergo heat treatments.
A first solution was proposed in patent EP-718 250. It recommends using,
on top of the silver-based functional layer or layers, oxygen barrier diffusion layers,
especially those based on silicon nitride, and placing the silver layers directly on
the subjacent dielectric coating, without interposition of priming layers or protective
metal layers. It proposes multilayers of the Si3N4/ZnO/Ag/Nb/ZnO/Si3N4 or
SnO2/ZnO/Ag/Nb/Si3N4 type. An Si3N4/Nb/Ag/Nb/Si3N4 multilayer is also described
in that document.
A second solution was proposed in patent EP-847 965; this is directed more
toward multilayers that include two silver layers, and it describes the use both of a
barrier layer on top of the silver layers (as previously) and of an absorbent or
stabilizing layer that is adjacent said silver layers and allows them to be stabilized.
It describes multilayers of the following type:
SnO2/ZnO/Ag/Nb/Si3N4/ZnO/Ag/Nb/WO3 or ZnO or SnO2/Si3N4.
It should be noted in both solutions that there is a metal layer, in this case
made of niobium, on the silver layers, preventing the silver layers from coming into
contact with an oxidizing or nitriding reactive atmosphere during deposition by
reactive sputtering of the ZnO layer or Si3N4 layer, respectively.
Another publication relating to multilayers containing one or two silver
layers, with adjusted optical properties without a major change in the optical
behavior in the event of heat treatment is the document WO-02/48065. This
describes multilayers in which at least one layer absorbent in the visible is inserted
between two dielectric layers, for example of the following type:
Si3N4 / ZnO / Ag / ZnO / Si3N4 / TiN or NbN / Si3N4 / ZnO / Ag / ZnO / Si3N4
or
Si3N4 / ZnO / Ag / Ti / ZnO / TiN / Si3N4 / ZnO / Ag / Ti / ZnO / TiN / Si3N4.
Document WO 01/40131 describes laminated glazing assemblies or
insulating glazing units of the low-emissivity type, that are capable of withstanding
a heat treatment in such a way that the treated glazing has an appearance similar
to or compatible with the untreated glazing: the treated and untreated glazing
assemblies may be fitted together in a glazed system forming a homogeneous unit
relatively uniform to the naked eye (what is called "matchable" glazing). This
relatively small change in property of the multilayer as a result of the heat
treatment is characterized by a change in colorimetric response in reflection, AE,
of less than about 5 (where ?E = (?L*2 + ?a*2 + ?b*2)½) and a change ?a* of less
than about 0.8.
Such glazing assemblies are provided with a multilayer comprising, starting
from the glass, a silicon nitride layer, an essentially thin metal layer based on
nickel or nickel alloy (1 to 2 nm in thickness), a silver layer, a thin essentially
metallic layer (1-2 nm) based on nickel or nickel alloy, and a silicon nitride layer.
However, the relatively small change in colorimetric response is
accompanied by an increase of at least 4% in the light transmission (change in
light transmission ?TL = 4%, especially 5%) with in particular a TL initially within the
63 to 73% range, but after heat treatment within the 68 to 78% range. A change in
light transmission of this order of magnitude is far from being an advantage from
the standpoint of combining, side by side, an untreated glazing assembly with a
thermally treated glazing assembly, since the difference in appearance between
the two is clearly detectable by the naked eye.
Document WO 97/48649 also describes a multilayer of the above type that
can be toughened, with two thin metal "blocking" layers, this time based on
niobium, with a thickness of 0.7 to 2 nm.
When this glazing assembly is connected to a toughening heat treatment,
the appearance of an intense uniform haze, and also corrosion spots, are
observed.
These two prior solutions, which rely on the use of a metal "blocking"
underlayer and overlayer, made from the same metal, therefore have significant
drawbacks.
The object of the invention is to alleviate these drawbacks by seeking to
improve the thin-film multilayers described above, especially by seeking to
improve their behavior with regard to heat treatments of the bending and/or
toughening type, in particular as regards optical changes and the appearance of
optical defects.
The subject of the invention is a glazing assembly comprising at least one
transparent substrate, especially made of glass, provided with a thin-film multilayer
comprising, in the following order starting from the substrate, at least:
(a) a first dielectric layer;
(b) a lower stabilizing layer made of a metal or metal alloy X;
(c) a functional layer having reflection properties in the infrared and/or in the solar
radiation, especially a metal layer;
(d) an upper metal blocking layer made of a metal or metal alloy Y;
(e) a second dielectric layer; and
(f) optionally, a protective oxide layer;
in which multilayer the metal or alloy X of the lower stabilizing layer is different
from the metal or alloy Y of the upper blocking layer.
Although the prior art teaches, unambiguously, how to protect the functional
layer by flanking it between two metal layers b and d of identical nature, the
inventors of the present invention have demonstrated a very substantial
improvement in the resistance to heat treatment as regards the optical properties
of the glazing assembly when two different metals are chosen to form said layers b
and d.
According to the present invention, it is considered that an alloy of two or
more metals is a different material from each of the constituent metals in the pure
state. However, it may be preferable for an alloy layer to contain only metals
different from the associated second metal layer. Moreover, it will be considered
that two alloys are different if they do not have the same quantitative or qualitative
composition; however, it will be preferable for at least one metal to differ between
these alloys, or even for each alloy to be based on different metals.
The improvement obtained according to the invention is a slight optical
variation characterized by a change in light transmission ?TL of at most 3% and/or
a change in the colorimetric response in external reflection ?E* between the case
before heat treatment and the case after heat treatment of at most 3, with neither
haze nor pitting.
The combination of good optical quality and of limited optical changes is
obtained by the judicious choice of different metal layers. One explanatory
hypothesis is based on the observation that the wetting of a metal drop A on a
metal layer X will be different from the wetting of X on A. This effect is due to
different surface energies in the case of A and X. It is therefore judicious to choose
the metals X and Y so as to obtain the best wetting on either side of the silver (or
other) functional layer so as to have the best adhesion and to obtain maximum
protection during the heat treatment.
The first dielectric layer (a) comprises an oxygen diffusion barrier layer
chosen from silicon nitrides, optionally containing at least one other metal, such as
aluminum.
This dielectric layer essentially has the function of blocking the diffusion of
oxygen into the multilayer, including at high temperature. Since nitrides are largely
inert when exposed to an oxidizing attack, they undergo no appreciable structural
modification or chemical modification (of the oxidative type) during a heat
treatment of the toughening type, and therefore cause virtually no optical
modification of the multilayer in the event of heat treatment, especially in terms of
light transmission level. This layer may also act as a diffusion barrier preventing
species from migrating from the glass, especially alkali metals. Furthermore,
thanks to its refractive index of about 2, it is readily placed in a multilayer of the
low-emissivity type.
This layer may generally be deposited with a thickness of at least 5 nm,
especially at least 10 nm, for example between 15 and 70 nm, especially around
30 to 60 nm.
The lower metal layer (b) may be made of a metal X chosen from titanium,
nickel, chromium, niobium, zirconium, tantalum, aluminum or a metal alloy
containing at least one of these metals. Among such choices, a nickel chromium
alloy proves to be particularly satisfactory.
Advantageously, the thickness of the layer (b) is chosen with a sufficient
value for the metal layer to oxidize only partly during a heat treatment, such as the
toughening treatment. Preferably, this thickness is less than or equal to 6 nm,
between 1 and 6 nm and preferably at least 1.5 nm.
A lower metal chosen from metals that have a low affinity for oxygen makes
it possible to limit the diffusion of residual oxygen through the silver layer and
helps to prevent the appearance of defects of the haze or pitting type. Since the
lower metal barely oxidizes at all during the heat treatment, its thickness is
advantageously chosen in such a way that most of the light absorption by the
multilayer is provided by this metal.
The functional layer (c) is typically a silver layer, but the invention applies in
the same way to other layers of reflective metals, such as silver alloys, especially
those containing titanium or palladium, or layers based on gold or copper. Its
thickness is especially from 5 to 13 nm, preferably around 6 to 12 nm.
The upper metal layer (d) may be made of a metal Y chosen from titanium,
nickel, chromium, niobium, zirconium, tantalum, aluminum and metal alloys
containing at least one of these metals, different from the metal or alloy X of the
layer (b). Advantageously, the metal Y is chosen from titanium, niobium, aluminum
and zirconium; it is preferably titanium.
Advantageously, the thickness of the layer (d) is chosen with a value
sufficient for the metal layer to oxidize only partly during a heat treatment, such as
toughening. Preferably, this thickness is less than or equal to 6 nm, it may be as
thin as about 0.4 nm and in particular lies within the range of around 0.4 to 4 nm.
An upper metal chosen from metals with a high affinity for oxygen
furthermore makes it possible to block the diffusion of oxygen through the
multilayer and therefore to provide effective protection of the functional silver layer.
However, this oxidation of the upper metal causes a change in the light
transmission ATl, and the maximum thickness of the upper metal layer (d) may be
chosen so as to limit this change.
When the lower layer (b) is made of a barely oxidizable metal, such as
nickel-chromium, and the upper layer (d) is made of a metal with a high affinity for
oxygen, such as titanium, niobium or zirconium, the thickness of the lower metal
layer (b) is advantageously chosen so as to be greater than that of the overlayer
(d). Choosing the thicknesses of the metal layers in this way makes it possible to
reduce the change in light transmission even more effectively.
Advantageously, the functional layer (c), typically made of silver, is in direct
contact with the metal coatings (d) and (b) placed above and below it.
The second dielectric layer (e) has a function similar to that of the layer (a).
It comprises an oxygen diffusion barrier layer chosen from silicon nitrides,
optionally containing at least one other metal such as aluminum, etc.
This layer may generally be deposited with a thickness of at least 5 nm,
especially at least 10 nm, for example between 15 and 70 nm. especially around
30 to 60 nm. It may in particular have a thickness greater than that of the first
dielectric layer (a).
Advantageously, at least one (in particular each) of the dielectric coatings
may comprise a layer based on one or more metal oxides. In particular, the upper
dielectric layer (e) may comprise, on its outer surface, an oxide layer (f) that
improves the scratch resistance of the multilayer.
It may be a layer based on zinc oxide or on a mixed oxide consisting of zinc
and another metal (of the Al type). It may also be based on oxides comprising at
least one of the following metals: Al, Ti, Sn, Zr, Nb, W, Ta. An example of a zinc-
based mixed oxide which can be deposited as a thin film according to the
invention is a mixed zinc tin oxide containing an additional element such as
antimony, as described in WO 00/24686.
The thickness of this oxide layer may be from 0.5 to 6 nm.
One nonlimiting embodiment of the invention consists in providing a
multilayer comprising, on glass, the following sequence:
.../silicon nitride/nickel chromium/Ag/titanium/silicon nitride/...
(a) (b) (c) (d) (e)
the silicon nitride possibly containing another element, of the Al type, in a minor
amount relative to Si.
In particular, the multilayer may comprise the double sequence
(a)/(b)/(c)/(d)/(e)/(a')/(b')/(c')/(d')/(e'), where a' is identical to or different from a, and
likewise in the case of b, b' c, c' d, d' and e, e', and in which the intermediate
dielectric layers (e) and (a') may merge as a single layer of the same dielectric.
This variant is illustrated by the multilayer, on glass: .../silicon nitride/nickel-
chromium/silver/titanium/silicon nitride/ nickel-chromium/silver/titanium/silicon
nitride.
As a variant, it is possible to associate with the silicon nitride layers, for
example, an oxide layer (SnO2, a mixed zinc tin oxide, etc.), reducing the
thickness of the silicon nitride layer accordingly.
The multilayer configuration according to the invention makes it possible to
eliminate essentially all the optical defects, especially defects of the haze or pitting
type, on the thin-film multilayer after heat treatment.
The coated substrates according to the invention have, when they are fitted
as a double-glazing unit with another substrate, a light transmission of between 40
and 70%, especially from 40 to 60%, and a selectivity of between 1.25 and 1.45,
especially around 1.4 (the selectivity being the light transmission/solar factor ratio,
where the solar factor is the ratio of the total energy entering a room through the
glazing assembly to the incident solar energy according to the Parry Moon
calculation for an air mass equal to 2).
They have a color in external reflection in the blue-green shades.
They may undergo heat treatments at a temperature of at least 100°C,
especially about 130°C, for the purpose of assembling a laminated glass, or more
than 500°C for the purpose of bending, toughening or annealing in particular (even
bending treatments that differ from one point on the substrate to another), while
maintaining a high light absorption even after toughening. This small optical
variation is characterized by a light transmission change ATL (measured under
illuminant D6s) between the case before bending and after bending of at most 3%,
especially at most 2 to 2.5%, in particular at most 2%, and/or a change in
colorimetric response in reflection ?E* between the case before bending and after
bending of at most 3, especially at most 2.5, where ?E* is expressed, in the
(L,a*,b*) colorimetry system, as follows: ?E* = (?L*2 + ?a*2 + ?b*2)y'.
The generally accepted criterion of toughenability in terms of change of
colorimetric response in external reflection is that ?E* between the case before
heat treatment and after heat treatment must be less than or equal to 2. However,
it appears that a slightly higher value than 2 (but less than 3) is acceptable from
the standpoint of the combined use of toughened and nontoughened volumes on
one and the same curtain wall, if this change in colorimetric response is
accompanied by a reasonable reduction in the level of reflection, preferably a
change in absolute value limited to 2 (l?Rextl = 2), in particular a change of at most
1.5 (l?Rextl = 15).
Double glazing units thus formed also exhibit a small change in colorimetric
response between normal incidence and non-normal incidence, both in the initial
state and in the toughened state.
The coated substrate may be used as laminated glazing, it being possible
for the multilayer to be placed beside the intermediate film within the laminated
assembly on the side facing the outside of the space defined by the glazing
assembly (face 2) or on the inside of the space defined by the glazing assembly
(face 3). In such a glazing assembly at least one substrate may be toughened or
hardened, especially the one bearing the multilayer. The coated substrate may
also be combined with at least one other glass pane via a gas space in order to
make an insulating multiple glazing (double glazing) unit. In this case, the
multilayer preferably faces the intermediate gas space (face 2). A double glazing
unit according to the invention may incorporate at least one laminated glass pane.
Advantageously, once the substrate has been provided with the thin-film
multilayer, it undergoes a heat treatment at more than 500°C in order to toughen it,
with, after toughening, a color in external reflection characterized by a* b* The present invention also relates to a glazed unit incorporating several
glazing assemblies according to the invention and especially to a glazed assembly
incorporating at least one glazing assembly that has undergone a heat treatment
and at least one glazing assembly that has not undergone heat treatment.
The invention will now be described in greater detail by means of the
nonlimiting examples that follow.
In all the following examples, the layers are deposited by magnetically
enhanced sputtering on a clear silica-soda-lime glass pane 4 mm in thickness of
the PLANILUX type (glass sold by Saint-Gobain Glass).
The silicon-nitride-based layers are deposited from Al-doped Si targets in a
nitriding atmosphere. The Ag-based layers are deposited from Ag targets in an
inert atmosphere and the Ti-based layers from a Ti target, also in an inert
atmosphere. The NiCr layers are deposited in an inert atmosphere from nickel-
chromium alloy targets in portions of 80/20 by weight.
EXAMPLES 1 and 2
These examples relate to a multilayer:
Glass/AI:Si3N4/NiCr/Ag/Ti/AI:Si3N4,
where AI:Si3N4 means that the nitride contains aluminum.
Table 1 below repeats the multilayer, with the thicknesses indicated in
nanometers for each of the two examples:
These coated glass assemblies were subjected to a toughening operation
at above 600°C.
The overall optical quality of the glass after heat treatment was evaluated
by observing if any defects, whether localized or not, of the pitting or haze type
appeared. The glazing assembly was aluminated with an intense light coming, for
example, from a halogen spot. A qualitative rating was assigned according to the
following parameters:
The change in appearance of the glass panes before and after the heat
treatment was then evaluated by measuring the change in light transmission ?TL
and the level of reflection as a percentage (averaged change; under illuminant D65;
standard observer at 2°) and the change in appearance AE* (a unitless quantity,
the formula for which was mentioned above) in external reflection, internal
reflection and in transmission. These values, and the light transmission values T
(again under illuminant D65 at 2°) in %, of external light reflection Rext and internal
light reflection Rint, also in %, the values of I*, a* and b* in external reflection and
internal reflection (a unitless quantities), the dominant wavelength and the purity in
transmission, and also the solar factor SF (Parry Moon, mass 2) are given in
Tables 2 and 3 below.
The optical changes were measured on double glazing units comprising a 6
mm thick substrate according to the invention, the substrate being separated by a
12 mm thick argon space, the multilayer-coated surface of the substrate according
to the invention being turned toward the associated substrate.
The light transmission and reflections were measured using an integrating-
sphere measurement apparatus that measures the light flux in all directions on
one side of the substrate or on the other.
The multilayer according to Examples 1 and 2 after toughening exhibits very
good optical quality with no haze or corrosion pitting, receiving the rating +++.
The colorimetric behavior of the glazing assembly demonstrates a relatively
small change with regard to the angle of incidence, as indicated in Table 4 below
which presents the change in appearance in external reflection for various angles
of incidence, this change being calculated between toughened and nontoughened
Moreover, a* and b* vary only slightly with the angle of incidence, and also
in the direction of limiting the change in appearance when the observer moves
away from normal incidence, so that the toughenability criteria are even better
satisfied. This is an appreciable advantage, especially for the production of large
glazed units for which it is desirable to see the same color at all angles of
observation.
COMPARATIVE EXAMPLE 1
This is a multilayer according to document WO 01/40131 in which the two
metal blocking layers are made of nickel chromium. It is identical to Example 1,
except that the Ti layer (d) is replaced with an NiCr layer 1.2 nm in thickness.
When it undergoes a toughening heat treatment such as that carried out on
the previous examples, this multilayer manifests a light transmission change of
greater than 4%, being around 5%, which is more than twice as large as the
observed change with the invention.
COMPARATIVE EXAMPLE 2
This is a multilayer similar to that of Comparative Example 1, in which both
metal layers (b) and (d) are made of titanium.
This multilayer demonstrates, after heating, an intense uniform haze and a
few corrosion pits, penalized by the — rating.
The change in light transmission measured using an integrating sphere is
acceptable, but it drops considerably when it is measured in the direction of
incidence, owing to the strong scattering that gives the haze effect.
EXAMPLE 3
This example according to the invention differs from Example 1 by the fact
that the metal layers (b) and (d) are inverted, thus the titanium layer becomes the
lower layer and the nickel-chromium layer becomes the upper layer.
When this multilayer undergoes a toughening heat treatment, it results in
the following optical changes:
The toughened multilayer has an acceptable optical quality, but exhibits a
light haze, awarded the ++ rating.
Comparing this example with Example 1 shows that it is preferable to place
the metal with a low affinity for oxygen as the lower layer and the metal with a high
affinity for oxygen as the upper layer.
EXAMPLE 4
This example according to the invention differs from Example 1 by the fact
that the metal layer (d) is this time made of niobium with a thickness of 1.5 nm.
The multilayer is the following:
Glass/Si3N4(37)/NiCr(3.2)/Ag(7)/Nb(1.5)/Si3N4(54)
The optical changes are given in Table 6 below.
This multilayer demonstrates, after heating, a very good optical quality
without any haze or corrosion pits, receiving the +++ rating.
COMPARATIVE EXAMPLE 3
This is a multilayer according to document WO 97/48649 in which the two
metal blocking layers are made of niobium. It is identical to Example 1 except that
the layers (b) and (d) are made of Nb with a thickness of between 0.7 and 2 nm.
After heating, this multilayer demonstrates an intense uniform haze and
several corrosion pits, penalized by the — rating.
The change in light transmission measured using an integrating sphere is
acceptable, but drops considerably when it is measured in the direction of
incidence, owing to the strong scattering that gives the haze effect.
These examples show that by choosing two metal layers made of different
metals, a very considerable improvement is made over a multilayer using the
same metal or alloy, even with different thicknesses, on either side of the silver.
These examples must not be regarded as describing the invention in a
limiting manner, the invention also applies to multilayers using another functional
layer, and also several functional layers.
Of course, a person skilled in the art is capable of producing different
embodiments of the invention without thereby departing from the scope of the
patent as defined by the claims.
WE CLAIM:
1. A glazing assembly comprising at least one transparent substrate,
especially made of glass, provided with a thin-film multiplayer comprising, in
the following order starting from the substrate, at least:
(a) a first dielectric layer comprising a barrier layer acting as a barrier
to the diffusion of oxygen and chosen from silicon nitrides;
(b) a bwer stabilizing layer made of a metal or metal alloy X such as
herein described;
(c) a functional layer having reflection properties in the infrared and/or
in the solar radiation, especially a metal layer such as herein
described;
(d) an upper metal blocking layer made of a metal or metal alloy Y
such as herein described;
(e) a second dielectric layer comprising a barrier layer acting as a
barrier to the diffusion of oxygen and chosen from silicon nitrides;
and
(f) optionally, a protective oxide layer;
in which muitiplayer the metal or alloy X of the lower stabilizing layer is
different from the metal or alloy Y of the upper blocking layer.
2. The glazing assembly as claimed in claim 1, wherein the thickness of the
dielectric layer (a) and (e) respectively, is at least 5 nm, especially between
15 and 70 nm.
3. The glazing assembly as claimed in any one of the preceding claims,
wherein the stabilizing lower metal layer (b), respectively the upper metal
layer (d), is made of a metal or alloy X, respectively Y, chosen from titanium,
nickel, chromium, niobium, zirconium, tantalum, aluminium or metal alloy
containing at least one of these metals.
4. The glazing assembly as claimed in claim 3, wherein the stabilizing
lower metal layer (b) is made of a nickel-chromium alloy.
5. The glazing assembly as claimed in any one of the preceding claims,
wherein the thickness of the layer (b) is between 1 and 6 nm.
6. The glazing assembly as claimed In any one of the preceding claims, the
layer (c) is a metal layer based on silver, titanium, palladium or gold.
7. The glazing assembly as claimed in claim 6 wherein the layer (c) has a
thickness of 6 to 12 nm.
8. The glazing assembly as claimed in claim 3, wherein the upper metal
blocking layer (d) is made of a metal Y chosen from titanium, zirconium,
niobium and aluminum.
9. The glazing assembly as claimed in any one of the preceding claims
wherein the thickness of the layer (d) in the range of 0.4 to 6 nm.
10. The glazing assembly as claimed in one of the preceding claims,
wherein the thickness of the layer (b) is greater than that of the layer (d).
11. The glazing assembly as claimed in any one of the preceding claims
wherein at least one (in particular each) of the dielectric coatings may
comprise a layer based on one or more metal oxides.
12.The glazing assembly as claimed in any one of the preceding claims,
wherein it comprises an outer layer (f) based on an oxide of at least one
metal chosen from Zn, Al, Ti,Sn, Zr, Nb, W, Ta.
13. The glazing assembly as claimed in any one of the praceding claims,
wherein the multiplayer comprises, on glass, the sequence:
.../silicon nitride/nickel-chromium/Ag/titanium/silicon nitride/...
(a) (b) (c) (d) (e)
14. The glazing assembly as claimed in claim 13, wherein the multiplayer
comprises the sequence.
....../silicon nitricte/nickel-chromium/Ag/titanium/silicon nitride/nickel-
chromium/Ag/titanium/silicon nitride/...
15. The glazing assembly as claimed in any one of the preceding claims,
wherein it is mounted with another substrate as a double glazing assembly and
The unit has a light transmission of between 40 and 70%.
16. The glazing assembly as claimed in any one of the preceding claims,
wherein it has a selectivity defined by the ratio of the light transmission to the
solar factor, TL/SF, of between 1.25 and 1.45.
17. The glazing assembly as claimed in any one of the preceding claims,
Wherein it has a blue-green color in reflection.
18. The glazing assembly as claimed in any one of the preceding claims
wherein the substrate, once it has been provided with the thin-film multiplayer,
undergoes a heat treatment at more than 500°C, of the bending, toughening or
annealing type, especially with an average ligh transmission change ?T,
induced by the heat treatment of at most 3%, preferably around 2%, and/or an
average change in colorimetric response in reflection induced by the heat
treatment ?E* of at most 3, especially 2.5.
19. A glazed unit incorporating several glazing assemblies as claimed in any
one of claims 1 to 8.
20. The glazed unit as claimed in the preceding claim, wherein it incorporates
at least one glazing assembly that has undergone a heat treatment and at toast
one glazing assembly that has not undergone heat treatment.

A glazing assembly comprising at least one transparent substrates, especially
made of glass, provided with a thin-film multiplayer comprising, in the following
order starting from the substrate, at least: (a) a first dielectric layer comprising a
barrier layer acting as a barrier to the diffusion of oxygen and chosen from
silicon nitrides; (b) a lower stabilizing layer made of a metal or metal alloy X such
as herein described; (c) a functional layer having reflection properties in the
infrared and/or in the solar radiation, especially a metal layer such as herein
described; (d) an upper metal blocking layer made of metal or metal alloy Y such
as herein described; (e) a second dielectric layer comprising a barrier layer acting
as a barrier to the diffusion of oxygenand chosen from silicon nitrides; and (f)
optionally, a protective oxide layer; in which multiplayer the metal or alloy X of
the lower stabilizing layer is different from the metal or alby Y of the upper
blocking layer; in which multiplayer the metal or alby X of the bwer stabilizing
layer is different from the metal or alby Y of the upper blocking layer.

Documents:

2687-KOLNP-2005-FORM 27-1.1.pdf

2687-KOLNP-2005-FORM 27.pdf

2687-KOLNP-2005-FORM-27.pdf

2687-kolnp-2005-granted-abstract.pdf

2687-kolnp-2005-granted-claims.pdf

2687-kolnp-2005-granted-correspondence.pdf

2687-kolnp-2005-granted-description (complete).pdf

2687-kolnp-2005-granted-examination report.pdf

2687-kolnp-2005-granted-form 1.pdf

2687-kolnp-2005-granted-form 18.pdf

2687-kolnp-2005-granted-form 2.pdf

2687-kolnp-2005-granted-form 3.pdf

2687-kolnp-2005-granted-form 5.pdf

2687-kolnp-2005-granted-gpa.pdf

2687-kolnp-2005-granted-reply to examination report.pdf

2687-kolnp-2005-granted-specification.pdf

2687-kolnp-2005-granted-translated copy of priority document.pdf


Patent Number 233842
Indian Patent Application Number 2687/KOLNP/2005
PG Journal Number 16/2009
Publication Date 17-Apr-2009
Grant Date 16-Apr-2009
Date of Filing 23-Dec-2005
Name of Patentee SAINT-GOBAIN GLASS FRANCE
Applicant Address LES MIROIRS, 18 AVENUE D'ALSACE, F-92400 COURBEVOIE
Inventors:
# Inventor's Name Inventor's Address
1 BROCHOT JEAN-PIERRE SAINT-GOBAIN RECHERCHE 39 QUAI LUCIEN LEFRANC, 93303 AUBERVILLIERS
2 BELLIOT SYLVAIN SAINT-GOBAIN RECHERCHE 39 WUAI LUCIEN, 93303 AUBERVILLIERS
PCT International Classification Number C03C 17/36
PCT International Application Number PCT/FR2004/001622
PCT International Filing date 2004-06-25
PCT Conventions:
# PCT Application Number Date of Convention Priority Country
1 03/07749 2003-06-26 France