Note: Descriptions are shown in the official language in which they were submitted.
2178033
- ~.
A glazing panel having solar screening properties and a process for
making such a panel.
The present invention relates to a glazing panel having solar screening
properties and to a process for making such a panel.
Reflective transparent solar control glazing panels have become a useful
material for architects to use for the exterior facade of buildings.Such
panels have
aesthetic qualities in reflecting the immediate environment and, being
available in a
number of colours, in providing a design opportunity. Such panels also have
technical advantages by providing the occupants of a building with protection
against
solar radiation by reflection and/or absorption and eliminating the dazzling
effects of
intense sunshine, giving an effective screen against glare, enhancing visual
comfort
and reducing eye fatigue.
From a technical point of view, it is desired that the glazing panel shall
not pass too great a proportion of total incident solar radiation in order
that the
interior of the building shall not become overheated in sunny weather. The
transmission of total incident solar radiation may be expressed in terms of
the "solar
factor". As used herein, the term "solar factor" means the sum of the total
energy
directly transmitted and the energy which is absorbed and re-radiated on the
side
away from the energy source, as a proportion of the total radiant energy
incident of
the coated glass.
Another important application of reflective transparent solar control
glazing panels is in vehicle windows, especially for motor cars or railway
carriages,
where the objective is to protect the vehicle occupants against solar
radiation. In this
case the main energy factor to be considered is the total energy directly
transmitted
(TE), since the energy which is internally absorbed and re-radiated (AE) is
dissipated
by the movement of the vehicle. The essential aim of the vehicle panel is thus
to have
a low TE factor.
The properties of the coated substrate discussed herein are based on
the standard definitions of the International Commission on Illumination -
Commission Internationale de 1 E'clairaye ("CIE").
The standard illuminants quoted herein are CIE Illuminant C and
Illuminant A. Illuminant C represents average daylight having a colour
temperature of
6700 K. Illuminant A represents the radiation of a Planck radiator at a
temperature of
about 2856 K.
The "luminous transmittance" (TL) is the luminous flux transmitted
2178033
2.
through a substrate as a percentage of the incident luminous flux.
The "luminous reflectance" (RL) is the luminous flux reflected from a
substrate as a percentage of the incident luminous flux.
The "selectivity" of a coated substrate for use in a building glazing
panel is the ratio of the luminous transmittance to the solar factor (TUFS).
The " purity" (p) of the colour of the substrate refers to the excitation
purity measured with Iltuminant C. It is specified according to a linear scale
on which
a defined white light source has a purity of zero and the pure colour has a
purity of
100%. The purity of the coated substrate is measured from the side opposite
the
coated side.
The term "refractive index" (n) is defined in the CIE International
Lighting Vocabulary, 1987, page 138.
The "dominant wavelength" RD) is the peak wavelength in the range
transmitted or reflected by the coated substrate.
The "emissivity" (e) is the ratio of the energy emitted by a given surface
at a given temperature to that of a perfect emitter (black body with
emissivity of 1.0)
at the same temperature.
A number of techniques are known for forming coatings on a vitreous
substrate, including pyrolysis. Pyrolysis generally has the advantage of
producing a
hard coating, which precludes the need for a protective layer. The coatings
formed by
pyrolysis have durable abrasive- and corrosion-resistant properties. It is
believed that
this is due in particular to the fact the process involves depositing of
coating material
onto a substrate which is hot. Pyrolysis is also generally cheaper than
alternative
coating processes such as sputtering, particularly in terms of the investment
in plant.
The deposit of coatings by other processes, for example by sputtering, led to
products
with very different properties, in particular a lower resistance to abrasion
and
occasionatly a different refractive index.
A wide variety of coating materials have been proposed for glazing
panels, and for several different desired properties of the glazing. Tin
oxide, SnO2,
has been widely used, often in combination with other materials such as other
metal
oxides.
GB patent 1455148 teaches a method for pyrolytically forming a
coating of one or more oxides on a substrate, primarily by spraying compounds
of a
metal or silicon, so as to modify the light transmission and/or light
reflection of the
substrate, or to impart antistatic or electrically conductive properties. Its
examples of
specified oxides include Zr02, SnO2, Sb203, Ti02, Co304, Cr203, Si02 and
mixtures
thereof. Tin oxide (SnO2) is seen as advantageous because of its hardness and
its
abitity to have antistatic or electrically conductive properties. GB patent
2078213
2273033
3.
relates to a sequential spray method for pyrolytically forming a coating on a
vitreous
support and is particularly concerned with tin oxide or indium oxide as the
main
coating constituents. When its metal coating precursor is tin chloride this is
advantageously doped with a precursor selected from ammonium bifluoride and
antimony chloride in order to increase the electrical conductivity of the
coating.
It is also known that where a coating of tin oxide is formed by pyrolysis
of SnC4, the presence of a dopant such as antimony chloride SbC15, directly
mixed
with the tin chloride SnC4, improves the absorption and reflection of some
near solar
infrared radiation.
It is an object of the present invention to provide a pyrolytically formed
glazing panel having solar screening properties.
We have discovered that this and other useful objectives can be
achieved by utilising chemical vapour deposition (CVD) to apply a pyrolytic
coating
comprising tin and antimony oxides in a specific relative ratio.
Thus, according to a first aspect of the present invention, there is
provided a glazing panel comprising a vitreous substrate carrying a
tin/antimony
oxide coating layer containing tin and antimony in a Sb/Sn molar ratio of from
0.01
to 0.5, the said coating layer having been pyrolytically formed by chemical
vapour
deposition, whereby the so-coated substrate has a solar factor FS of less than
70%.
The substrate is preferably in the form of a ribbon of vitreous material,
such as glass or some other transparent rigid material. In view of the
proportion of
incident solar radiation which is absorbed by the glazing panel, especially in
environments where the panel is exposed to strong or long-term solar
radiation, there
is a heating effect on the glass panel which may require that the glass
substrate be
subsequently subjected to a toughening process. However, the durability of the
coating enables the glazing panel to be mounted with the coated face
outermost, thus
reducing the heating effect.
Preferably, the substrate is clear glass, although the invention also
extends to the use of coloured glass as the substrate.
The Sb/Sn molar ratio in the coating layer is preferably at least 0.03,
most preferably at least 0.05. This assists in ensuring a high level of
absorption. On
the other hand the said ratio is preferably less than 0.21, with a view to
achieving a
high level of luminous transmittance (TL). Most preferably the ratio is less
than 0.15,
since above this level the coating layer displays an unduly high level of
absorption,
coupled with poor selectivity.
Coated substrates according to the invention offer the advantage of a
luminous reflectance (RL) of less than 11%. This low level of reflection in a
building
glazing panel is much favoured by architects. It avoids the panels creating
glare in the
2178033
4.
vicinity of the building.
It may be useful to prevent interaction between the glass of the
substrate and the tin/antimony oxide coating layer. As an example, it has been
found
that in the pyrolytic formation of a tin oxide coating from tin chloride on a
soda-lime
glass substrate, sodium chloride tends to become incorporated into the coating
as a
result of reaction of the glass with the coating precursor material or its
reaction
products, and this leads to haze in the coating.
Thus, an intermediate haze-reducing coating layer is preferably
positioned between the substrate and the tin/antimony oxide coating layer. The
haze-
reducing layer may be pyrolytically formed in an incompletely oxidized state
by
contacting the substrate in an undercoating chamber with undercoat precursor
material in the presence of oxygen in insufficient quantity for full oxidation
of the
undercoat material on the substrate. The expression "incompletely oxidized
material"
is used herein to denote a true sub-oxide, that it to say an oxide of a lower
valency
state of a multivalent element (for example V02 or TiO), and also to denote an
oxide
material which contains oxygen gaps in its structure: an example of the latter
material
is SiOx where x is less than 2, which may have the general structure of Si02
but has a
proportion of gaps which would be filled with oxygen in the dioxide.
We prefer the haze-reducing coating layer to comprise a silicon oxide
having a geometric thickness such as about 100 nm. The presence of a silicon
oxide
undercoating on soda-lime glass has the particular benefit of inhibiting the
migration
of sodium ions from the glass whether by diffusion or otherwise into the
tin/antimony
oxide coating layer either during formation of that upper layer or during a
subsequent
high temperature treatment.
Alternatively, the undercoat may be constituted as an "anti-reflection"
undercoating such as, for example, an oxidised aluminium/vanadium layer as
described in GB patent specification 2248243.
The glazing panels according to the invention have a solar factor of less
than 70%, preferably less than 60% and in some instances preferably less than
50%.
The preference for a solar factor of less than 60% arises when the panels
according to
the invention are positioned with the coated side facing the exterior, i.e.
facing the
energy source. Generally, this positioning leads to a improved solar factor
compared
with the positioning of the panel with the coated side away from the energy
source.
The need for a solar factor of less than 50% arises for buildings in parts of
the world
with high levels of solar energy. For vehicle sunroofs an even lower solar
factor may
be desirable.
The use of coloured glass is one way of providing a lower solar factor,
and is commonly employed in both building glass and vehicle glass. In
comparing the
2178033
5.
effectiveness of coating layers it is therefore necessary to take into account
any
differences between the types of glass on which the respective coatings are
deposited.
Thus one example of a coating according to the invention on clear glass gave a
solar
factor of 63%, whereas an equivalent coating on a green coloured glass gave a
solar
factor of 44.5%.
It is also desired that the glazing panel shall also transmit a reasonable
proportion of visible light in order to allow natural illumination of the
interior of the
building or vehicle and in order to allow its occupants to see out. Thus it is
desirable
to increase the selectivity of the coating, that is to increase the ratio of
the
transmittance to the solar factor. Indeed it is preferred that the selectivity
be as high as
possible.
In general it is preferred that the luminous transmittance (TL) of the
panel according to the invention is between 40 and 65%. Nevertheless, a panel
having a light transmittance below 40% may be used as a roofing panel, for
example
as a vehicle sunroof.
Preferably, the tin/antimony oxide coating has a thickness of from 100
to 500 nm. Thick layers of tin/antimony oxide, particularly layers having a
low Sb/Sn
molar ratio, can provide a glazing panel with the advantageous combination of
a low
solar factor (FS) and low emissivity. Another way of obtaining this
combination is to
deposit on the tin/antimony oxide layer of the invention a low-emissivity
layer of
doped tin oxide, for example tin oxide doped with fluorine. However this is
disadvantageous in the sense that it makes necessary the deposition of a
supplementary layer, which is time-consuming and expensive.
In principle, another way to provide a combination of low solar factor
and low emissivity could be to form a tin/antimony oxide layer containing a
doping
agent such as fluorine. For example GB patent 2200139 teaches a method of
forming
a pyrolytic tin oxide coating by spraying a solution which in addition to the
tin
precursor contains compounds which will result in the coating containing
fluorine and
at least one of antimony, arsenic, vanadium, cobalt, zinc, cadmium, tungsten,
te(lurium and manganese.
Thus one could, for instance, form a coating from reactants containing
tin, antimony and fluorine in the ratios Sb/Sn = 0.028, F/Sn = 0.04. However
we
have discovered that the presence of fluorine has the apparent disadvantage of
hindering the incorporation of antimony in the coating rather than effectively
reducing the emissivity. For example reactants containing antimony and tin in
the
ratio Sb/Sn = 0.028 gave a coating with an Sb/Sn ratio of about 0.057, whilst
the
same reactants plus a fluorine-containing reactant in an amount such that F/Sn
=
0.04 gave a coating with an Sb/Sn ratio of about 0.038.
2178033
6.
The invention accordingly presents the advantage of simultaneously
providing a solar factor (FS) below 60%, an emissivity of less than 0.4
(preferably less
than 0.3) and a luminous transmittance (TL) of more than 60%. Thus the coated
product fulfil two important functions. In winter it maintains the heat in the
building,
because of its low emissivity. In summer it resists the passage of solar heat
into the
building and thus avoids overheating inside the building, thanks to its low
solar factor.
This is especially achieved for coatings having an Sb/Sn ratio between 0.01
and 0.12,
especially 0.03 to 0.07, and a thickness between 100 and 500 nm, for example
between 250 and 450 nm.
Preferably the tin/antimony oxide coating layer is an exposed coating
layer and the glazed panel comprises only one such tin/antimony oxide coating
layer.
However, it is possible to provide one or more further coating layers,
whether by pyrolysis or by other coating methods, to achieve certain desired
optical
qualities. It should be noted however, that the tin/antimony oxide layer when
applied
by pyrolysis has sufficient mechanical durability and chemical resistance to
suitably
serve as the exposed layer.
The panels according to the invention may be installed in single or
multi-glazed assemblies. While the coated surface of the panel may be the
inside
surface of the exterior glazing panel so that the coated surface is not
exposed to the
ambient weather conditions which might otherwise more rapidly reduce its life
by
soiling, physical damage and/or oxidation, coatings produced by pyrolysis
generally
have a greater mechanical resistance than coatings produced by other methods
and
they may therefore be exposed to the atmosphere. The panels according to the
invention may usefully be employed in laminated glass structures, for example
where
the coated surface is the inside surface of the exterior laminate.
According to a second aspect of the invention, there is provided a
process of forming a glazing panel comprising the chemical vapour deposition
of a
tin/antimony oxide layer from a reactant mixture on to a vitreous substrate,
said
reactant mixture comprising a source of tin and a source of antimony, the
Sb/Sn
molar ratio in said mixture being from 0.01 to 0.5, whereby the so-coated
substrate
has a solar factor FS of less than 70%.
When it is desired to manufacture pyrolytically coated flat glass, it is
best to do so when the glass is newly formed. To do so has economic benefits
in that
there is no need to reheat the glass for the pyrolytic reactions to take
place, and it
also has benefits as to the quality of the coating, since it is assured that
the surface of
the glass is in pristine condition. Preferably, therefore, said coating
precursor material
is brought into contact with an upper face of a hot glass substrate
constituted by
freshly-formed flat glass.
2178033
7.
Thus, the glazing panels according to the invention may be
manufactured as follows. Each pyrolytic coating step may be carried out at a
temperature of at least 400 C, ideally from 550 C to 750 C. The coatings can
be
formed on a sheet of glass which moves in a tunnel oven or on a glass ribbon
during
formation, whilst it is still hot. The coatings can be formed inside the lehr
which
follows the glass ribbon forming device or inside the float tank on the top
face of the
glass ribbon whilst the latter is floating on a bath of molten tin.
The coating layers are applied to the substrate by chemical vapour
deposition (CVD). This is a particularly beneficial method because it provides
for
coatings of regular thickness and composition, such uniformity of the coating
being
particularly important where the product is to cover a large area. CVD offers
many
advantages over pyrolysis methods using sprayed liquids as the reactant
materials.
With such spray methods it is difficult both- to- control the- vaporisation
process and to
obtain a good uniformity of coating thickness. Moreover, the pyrolysis of
sprayed
liquids is essentially limited to the manufacture of oxide coatings, such as
SnO2 and
TiO2. It is also difficult to make multi-layer coatings using sprayed liquids
because
every coating deposition produces a significant cooling of the substrate.
Furthermore,
chemical vapour deposition is more economic in terms of raw materials, leading
to
lower wastage.
The product with a CVD coating is physically different from those with
coatings obtained by spraying. Notably a spray coating retains traces of the
sprayed
droplets and of the path of the spray gun, which is not the case with CVD.
To form each coating, the substrate is brought into contact, in a coating
chamber, with a gaseous medium comprising the reactant mixture in the gaseous
phase. The coating chamber is fed with the reactant gas through one or more
nozzles,
the length of which is at least equal to the width to be coated.
Methods and devices for forming such a coating are described for
example in French patent No 2 348 166 (BFG Glassgroup) or in French patent
application No 2 648 453 Al (Glaverbel). These methods and devices lead to the
formation of particularly strong coatings with advantageous optical
properties.
To form the coatings of tin/antimony oxide, two successive nozzles are
used. The reactant mixture comprising the sources of tin and antimony are fed
in at
the first nozzle. Where this mixture comprises chlorides which are liquid at
ambient
temperature, it is vaporised in a current of anhydrous carrier gas at an
elevated
temperature. Vaporisation is facilitated by the atomization of these reagents
in the
carrier gas. To produce the oxides, the chlorides are brought into the
presence of
water vapour conducted to the second nozzle. The water vapour is superheated
and
is also injected into a carrier gas.
21780,33
8.
Advantageously, nitrogen is used as the substantially inert carrier gas.
Nitrogen is sufficiently inert for the purposes in view, and it is inexpensive
when
compared with the noble gases.
Undercoatings of silicon oxide Si02 or SiOX may be deposited from
silane SiH4 and oxygen in accordance with the descriptions in British patent
specifications GB 2234264 and GB 2247691.
If a glass substrate bearing an incompletely oxidised coating is exposed
to an oxidizing atmosphere for a sufficiently long period of time, it may be
expected
that the coating will tend to become fully oxidized so that its desired
properties are
lost. Therefore, such undercoat is over-coated with the tin/antimony oxide
coating
layer while it is still in an incompletely oxidized state, and while the
substrate is still
hot, thereby to preserve such undercoat in an incompletely oxidized state. The
time
during which the freshly undercoated glass substrate may be exposed to an
oxidizing
atmosphere such as air and before the undercoat is over-coated, without
damaging
the properties of the undercoat, will depend on the temperature of the glass
during
such exposure and on the nature of the undercoat.
Advantageously, said undercoating chamber is surrounded by a
reducing atmosphere. The adoption of this feature assists in preventing
ambient
oxygen from entering the undercoating chamber and accordingly allows better
control
of the oxidizing conditions within that undercoating chamber.
The oxygen required for the undercoating reactions may be supplied as
pure oxygen, but this adds unnecessarily to costs, and it is accordingly
preferred that
air is supplied to the undercoating chamber in order to introduce oxygen
thereto.
It will be noted that the Sb/Sn molar ratio which is desirable in the
reactant mixture does not always correspond to that ratio which is desirable
for the
tin/antimony coating layer
Preferably the source of tin is selected from SnC4, monobutyl trichloro
tin ("MBTC") and mixtures thereof. The source of antimony may be selected from
SbCl5, SbCl3, organo antimony compounds and mixtures thereof. Examples of
suitable source materials are Sb(OCH2CH3)36 C11.7Sb(OCH2CH3)1.3,
C12SbOCHCICH3,
CI2SbOCH2CHCH3CI and Cl2SbOCH2C(CH3)2C1.
The invention will now be described in more detail, with reference to
the following non-limiting examples.
In the Examples the Sb/Sn molar ratio in the coating layers was
determined by an X-ray analysis technique in which the number of X-ray counts
of
the respective elements was compared. While this technique is not as precise
as if a
calibration by chemical dosage were made, the similarity of antimony and tin
means
that they respond similarly to X-rays. The ratio of the measured number of
observed
2178033
9.
counts of the respective elements thus provides a close approximation to their
molar
ratio.
Coloured rather than clear glass was employed as indicated in some of
the Examples. The properties of the respective types of coloured glass are
shown in
Table 1 below. In all cases the properties were measured on glass samples
having a
thickness of 4 mm, this being the thickness of glass employed in all the
examples
except Examples 1 to 7 (for which the thicknesses are shown in Table 2). The
initials
in the headings to this and the other following tables (TL, TE etc.) have the
meanings
described above.
With regard to the calculation of the solar factor, it should be noted that
for luminous transmittances (TL) below 60% the effect of low emissivity is not
negligeable and should be taken into account: as the emissivity reduces so
equally
does the solar factor.
Table 1
Glass Type Green A Green B Grey Medium Dark Grey
Grey
%D in transmission (nm) 505.4/508.5 504.9/508.4 470.1/493.9 493.2/502.7
478.9/502.7
[Illuminant: C/A]
Puri (%) 2.9/3.4 2.1/2.5 1.5/0.8 5.6/5.1 2.6/1.8
TL (%) 72.66/71.12 78.44/77.20 55.65/55.56 36.80/35.76 22.41/22.30
[Illuminant: C/A
TE (%) (CIE) 44.0 52.3 56.9 25.9 31.11
FS (%) coated side 56.8 62.9 66.3 43.4 47.3
CIE)
TL/FS 1.28 1.25 0.84 0.85 0.47
[Illuminant: C]
Example 1
Clear soda-lime float glass advancing at a speed of 7 metres per minute
along a float chamber was undercoated at a coating station located at a
position
along the float chamber where the glass was at a temperature of about 700 C.
The
supply line was fed with nitrogen, silane was introduced thereto with a
partial
pressure of 0.25%, and oxygen was introduced with a partial pressure of 0.5%
(ratio
0.5). A coating of silicon oxide Si02 having a thickness of 100 nm was
obtained.
The undercoated substrate, having a thickness of 6 mm was then
immediately coated by CVD pyrolysis using a coating apparatus comprising two
successive nozzles. A reagent comprising a mixture of SnC4 as a source of tin
and
SbCl5 as a source of antimony was used. The Sb/Sn molar ratio in the mixture
was
2178033
10.
about 0.2. The reactant mixture was vaporised in a current of anhydrous
nitrogen gas
at about 600 C, was fed in at the first nozzle. Vaporisation was facilitated
by the
atomization of these reagents in the carrier gas. Superheated water vapour was
conducted to the second nozzle. The water vapour was heated to about 600 C,
and
was also injected into a carrier gas, which was air heated to about 600 C. The
flow
rate of gas (carrier gas + reagent) in each nozzle was 1 m3/cm width of
substrate per
hour, at the operating temperature.
The coating process was continued until the geometrical thickness of
the tin/antimony oxide coating superimposed on the undercoated substrate was
185
nm.
Examples 2 to 7
In Examples 2 to 7, the procedure of Example 1 was followed but with
variations in such parameters as the reactant mixture, the presence or absence
of an
undercoat oxide, the ratio of Sb/Sn in the coating and in the reactant mixture
and the
thickness of the glass substrate. For instance, compared with Example 1, in
Example
2 no undercoating was applied and the tin/antimony oxide coating layer had a
thickness of 210 nm. The reactant mixtures were as follows:
Examples 2 and 3: the same as in Example 1 (but with a lower
concentration of the reactant mixture in the carrier gas in Example 3);
Example 4: MBTC and Cl1.7Sb(OCH2CH3)1,3;
Example 5: MBTC and C12SbOCH2CHCH3Cl;
Example 6: MBTC and C12SbOCH2C(CH3)2C1;
Example 7: MBTC and SbCI3.
The variations in operating parameters for Examples 1 to 7 and the
results obtained are given in the accompanying Table 2.
The glazing panels according to Examples 3 to 7 had a pleasant blue
colour in transmission: the dominant wavelength in transmission in the visible
wavelength lay within the range of 470 to 490 nm.
Example 6 provided a glazing panel with the combination of a low solar
factor FS and low emissivity.
In a variant of Example 6 the SiO2 undercoating was replaced by an
anti-reflection undercoating of silicon oxide SiOX according to the procedure
of GB
patent 2247691. In another variant the Si02 undercoating was replaced by an
oxidised aluminium/vanadium layer according to GB patent 2248243. In these
variants the glazing panel had no purple aspect in the reflection from the
uncoated
side.
Example 8
Coloured float glass "Green A" advancing at a speed of 7 metres per
2 173033
11.
minute along a float chamber was undercoated at a coating station located at a
position along the float chamber where the glass was at a temperature of about
700 C. The supply line was fed with nitrogen, silane was introduced thereto
with a
partial pressure of 0.2%, and oxygen was introduced with a partial pressure of
0.5%
(ratio 0.55). A coating of silicon oxide SiOx, with x approximately equal to
1.8, was
obtained with a refractive index of about 1.7. The thickness of the coating
was 40
nm.
The undercoated substrate, having a thickness of 4 mm, was then
coated by CVD pyrolysis. A reagent comprising a mixture of MBTC as a source of
tin
and Cl1.7Sb(OCH2CH3)1,3 as a source of antimony was used. The Sb/Sn molar
ratio in the mixture was about 0.195 (mass ratio 0.2). The reactant mixture
was
vaporised in a current of anhydrous air at about 200 C, fed in at the nozzle.
Vaporisation was facilitated by the atomization of these reagents in the
carrier gas.
Superheated water vapour was then introduced, heated to about 200 C.
The coating process was continued until the geometrical thickness of
the tin/antimony oxide coating superimposed on the undercoated substrate was
120
nm.
Examples 9 to 14
In Examples 9 to 14, the procedure of Example 8 was followed but with
variations as shown in the accompanying Table 2 in such parameters as the
thickness
of the undercoat, the ratio of Sb/Sn in the coating and in the reaction
mixture, the
thickness of the tin/antimony oxide coating layer and the colour of the glass.
The
results of examples 8 to 14 are set out in Table 3.
s The glazing panels according to the Examples 9 to 14 had a pleasant
blue colour in transmission, the dominant wavelength in transmission in the
visible
wavelength lying within the range of 470 to 490 nm (Illuminant C).
In a variant of Example 9 in which the Green A glass was replaced by
Medium Grey glass, the resultant luminous transmittance (TL) was 20%, the
luminous
reflectance (RL) was 10% and the energy transmission (TE) was 15 %.
Examples 15 to 30
The procedure of Example 1 was followed for further Examples 15 to
30 with variations in the reactant mixture, the colour and thickness of the
glass
substrate, the thickness of undercoat oxide, and the ratio of Sb/Sn in the
reactant
mixture and in the coating. For Examples 15 to 22 the reactant mixture was
MBTC
and Cl1.7Sb(OCH2CH3)1.3 without trifluoroacetic acid whereas for Examples 23
to 30
the reactant mixture was MBTC and C11.7.Sb(OCH2CH3)1.3 with trifluoroacetic
acid.
The F/Sn ratio in the reactant mixture for these examples was 0.04.
2 l 73033
12.
The variations in operating parameters, and the results obtained, are
set out in the accompanying Table 4 for Examples 15 to 22 and in the
accompanying
Table 5 for Examples 23 to 30. The silicon oxide SiOx used in Examples 15 to
30 had
a value of x approximately equal to 1.8.
13.
Table 2
Example 1 2 3 4 5 6 7
Tin/antimony oxide thickness (nm) 185 210 105 120 105 445 110
Undercoat oxide Si02 absent absent SiO2 Si02 SiO2 Si02
Undercoat thickness (nm) 100 0 0 70 70 70 70
Sb/Sn ratio in coating 0.48 0.48 0.46 0.19 0.15 0.06 0.18
Sb/Sn ratio in reactants 0.20 0.20 0.20 0.20 0.20 0.10 0.20
Haze (%) 0.07 2.09 4.36 to 7.01 low low low low
N
TL (%) 45.7 44.3 65.5 51.0 61.6 47.5 55.0 --i
RL (%) (coated side) 9.0 12.0 18.8 12.0 11.7 6.6 13.7 co
0
t.N
FS (%) (coated side) (CIE) 55.3 56.9 66.0 58.4 62.2 47.2 59.6
TUFS 0.83 0.78 0.99 0.87 0.99 1.01 0.92
~.p in transmission (nm) 587.5 -560 480.1 478.8 481.0 483.0 479.3
Colour purity in transmission (%) 3.4 3.9 4.9 11.5 8.7 8.0 10.3
%.p in reflection from the coated side (nm) 472.3 494.5 575.3 579.5 577.6
490.0 577.0
Colour purity (%) in reflection froin the 36.9 7.0 19.1 35.0 35.2 6.0 33.1
coated side
Emissivity >0.7 >0.7 >0.7 0.84 0.71 0.25 0.79
Glass thickness (m-n) 6 6 6 5 5 5 5
14.
Table 3
Example 8 9 10 11 I2 13 14
Tin/antimony oxide thickness (nm) 120 120 320 470 470 320 470
Undercoat oxide Si02 Si02 SiO2 SiO2 SiO2 SiO2 SiO2
Undercoat thickness (nm) 40 70 40 40 40 40 40
Sb/Sn ratio in coating 0.10 0.18 0.09 0.09 0.09 0.09 0.09
Sb/Sn ratio in reactants 0.07 0.20 0.07 0.07 0.07 0.07 0.07
Haze (%) 0.36 0.1 1.0 1.8 1.8 1.0 1.8
TL (%) [Illuminant A/Illuminant C] 53/55 39/20 31/32 31/32 9/9 40/41 36 [A] N
RL (%) (coated side) [Illuminant A/C] 9/10 11/11 7/7 7/7 7/7 8/7 7 [A] Co
RL (%) (uncoated side) [Illuminant C] 8 8 6 6 5 7 - C=)
TE (%) (CIE) 31 25 25 18 9 21 27
FS (%) (coated side) (CIE) 45 41 41 36 29 39 43
TUFS 1.2/1.2 0.95/0.98 0.76/0.78 0.86/0.89 0.31/0.31 1.02/1.05 5.4 [A]
2.p in transmission (nm) 505.5/498.6 497.2/487.0 494.8/481.9 497.2/487.2
494.2/480.0 501.0/491.6 493.4 [A]
Colour purity in transmission (%) 4.4/4.2 6.2/8.9 4.9/8.1 7.6/10.8 7.0/11.8
7.2/8.6 5.4 [A]
~.p in reflection from the coated side (nm) 487.9/478.1 -572.5/566.9 -
511.8/512.2 -576.9/559.8 -555.4/550.1 -512.5/513.6 -576.0 [A]
Colour purity (%) in reflection from the 7.4/14.6 2.2/2.9 17.2/16.3 6.0/1.2
2.1/6.6 15.4/14.5 1.5 [A]
coated side
Emissivity 0.71 0.85 0.44 0.35 0.35 0.44 0.35
Colour of glass Green A Green A Grey Green B Dark grey Green A Clear soda
lime
15. '
Table 4
Example 15 16 17 18 19 20 21 22
Tin/antimony oxide thickness (nm) 320 320 320 320 390 390 390 390
Undercoat oxide SiOx SiO., SiO, SiOX SiOX SiOX SiOX SiOx
Undercoat thickness (nm) 60 (approx) 60 (approx) 60 (approx) 60 (approx) 80
(approx) 80 (approx) 80 (approx) 80 (approx)
Sb/Sn ratio in coating 0.053 0.053 0.053 0.053 0.058 0.058 0.058 0.058
Sb/Sn ratio in reactants 0.028 0.028 0.028 0.028 0.028 0.028 0.028 0.028
Haze (%) 0.65 0.65 0.65 0.65 1.2 1.2 1.2 1.2
TL (%) filluminant C] 68.8 55.7 60.1 28.2 61.0 49.2 25.0 53.1
N
RL (%) (coated side) 8.9 8.2 8.4 7.2 9.0 8.0 7.2 6.9
RL (%) (uncoated side) 8.9 7.3 7.8 5.0 7.8 6.5 4.8 8.2 Gt7
CD
TE (%) (CIE) 50.8 28.3 33.1 15.8 43.0 24.5 13.7 28.5
cs.,
FS (%) (coated side) (CIE) 60.3 43.6 47.2 34.4 54.7 40.9 32.9 40.1
TL/TE 1.35 2.00 1.82 1.75 1.42 1.96 1.79 1.86
TUFS 1.15 1.27 1.28 0.82 1.11 1.20 0.76 1.20
?1p in transmission (nm) 524.0 506.2 506.0 494.0 496.0 500.7 493.4 499.5
Colour purity in transmission (%) 0.5 3.1 2.3 5.8 2.2 4.7 7.5 4.1
?.p in reflection from the coated side (nm) 482.9 484.2 484.0 482.9 -495.2 -
493.8 -495.0 -550.3
Colour purity (%) in reflectioti from the 14.5 16.2 15.8 18.0 5.0 4.4 6.4 7.0
coated side
Einissivity 0.29 0.29 0.29 0.29 0.27 0.27 0.27 0.27
Colour of glass Clear Green A Green B Med. grey Clear Green A Med. grey Green
B
16.
Table 5
Example 23 24 25 26 27 28 29 30
Tin/antimony oxide thickness (nm) 290 290 290 290 410 410 410 410
Undercoat oxide SiOx SiOX SiOx SiOx SiOX SiOX SiOx SiOX
Undercoat thickness (nm) 80 (approx) 80 (approx) 80 (approx) 80 (approx) 90
(approx) 90 (approx) 90 (approx) 90 (approx)
Sb/Sn ratio in coating 0.038 0.038 0.038 0.038 0.037 0.037 0.037 0.037
Sb/Sn ratio in reactants 0.028 0.028 0.028 0.028 0.028 0.028 0.028 0.028
Haze (%) 0.82 0.82 0.82 0.82 1.2 1.2 1.2 1.2
TL (%) [Illuminant C] 70.2 56.7 61.0 28.7 64.2 51.9 26.9 56.4
RL (%) (coated side) 10.0 9.0 9.2 8.0 8.8 8.1 7.2 8.3
RL (%) (uncoated side) 9.5 8.0 8.3 5.2 7.7 6.6 4.8 6.9
TE (%) (CIE) 54.3 29.5 34.7 16.6 47.2 26.1 14.6 30.6
FS (%) (coated side) (CIE) 63.0 44.5 48.3 34.9 57.7 42.0 33.6 45.4
TVTE 1.30 1.90 1.74 1.71 1.36 2.00 1.73 1.81
TUFS 1.11 1.27 1.27 0.83 1.10 1.24 0.76 1.24
Xp in tratrsmission (nin) 581.3 538.8 549.4 498.5 568.6 535.9 502.7 543.7
Colour purity in transmission (%) 2.9 2.9 2.7 3.3 3.5 3.7 3.6 3.5
n,p in reflection from the coated side (nm) 510.3 508.6 508.9 507.2 549.3
505.1 491.8 507.0
Colour purity (%) in reflection from the 8.1 10.1 9.6 11.3 3.3 1.1 1.2 1.0
coated side
Emissivity 0.28 0.28 0.28 0.28 0.23 0.23 0.23 0.23
Colour of glass Clear Green A Green B Med. grey Clear Green A Med. grey Green
B
