FORM 2
THE PATENTS ACT, 1970
(39 of 1970)
&
THE PATENTS RULES, 2003
COMPLETE SPECIFICATION
(See section 10 and rule 13)
1. Title of the Invention
A MIXTURE CURABLE TO PROVIDE AN INTUMESCENT COATING MATERIAL
2. Applicant(s)
Name Nationality Address
ADVANCED INNERGY LTD British Quedgeley West Business Park Bristol
Road Gloucester Gloucestershire GL2
4PA, United Kingdom
3. Preamble to the description
The following specification particularly describes the invention and the manner in which it is to be performed
2
TECHNOLOGICAL FIELD
5
Examples of the disclosure relate to a mixture curable to provide an
intumescent coating material, a method of providing an intumescent coating material,
an intumescent coating material, an intumescent coating for protecting a substrate, a
method of protecting a substrate with an intumescent coating, and a protected
10 substrate.
BACKGROUND
It is often required to provide an intumescent coating around substrates such as
15 pipework, valves, I-beams, and other process components and structural members, for
example in hydrocarbon facilities on or off shore. There is also a requirement to
provide an intumescent coating around substrates used in transportation, for instance
automotive components and structural members of vehicles.
20 When subjected to a fire event an intumescent coating expands to form a
protective char. The protective Char acts as a physical barrier insulating the substrate
and therefore delaying the effects of a fire and slowing the rate of temperature
increase of the coated substrate. This therefore potentially protects the substrate from
failing or delays the occurrence of failure, thereby providing additional time to permit
25 evacuation, for example, of personnel from a hydrocarbon facility or of the occupants
of a vehicle, and/or for fire fighting.
There is a requirement to provide intumescent coatings which have improved
properties.
30
3
All proportions referred to in this specification are indicated as % by weight of
the total composition.
BRIEF SUMMARY
5
According to various, but not necessarily all, examples of the disclosure there
is provided a mixture curable to provide an intumescent coating material, wherein the
mixture comprises a silane-terminated polymer, a cross-linker for curing the silaneterminated polymer, an epoxy resin, a cross-linker for curing the epoxy resin, and an
10 intumescent package.
The ratio of silane-terminated polymer to epoxy resin may be from 0.75 to
0.25: 0.25 to 0.75, and may be from 0.6 to 0.4:0.4 to 0.6, and may be 1:1.
15 The mixture curable to provide an intumescent coating material may be a twopart mixture. Possibly, a first part of the two-part mixture comprises the epoxy resin
and the intumescent package, and a second part of the two-part mixture comprises the
silane-terminated polymer, the cross-linker for curing the silane-terminated polymer,
and the cross-linker for curing the epoxy resin.
20
The silane-terminated polymer may comprise silane-terminated polyether or
silane-terminated polyurethane. The mixture may comprise 10 to 30 % by weight of
the silane-terminated polymer, and preferably may comprise 14 to 20 % by weight of
the silane-terminated polymer.
25
The cross-linker for curing the silane-terminated polymer may comprise a
multifunctional silane, such as an amino silane. The mixture may comprise 1 to 3 %
by weight of the cross-linker for curing the silane-terminated polymer, and preferably
may comprise 1.4 to 2 % by weight of the cross-linker for curing the silane30 terminated polymer.
4
The mixture may comprise 6 to 25 % by weight of the epoxy resin, and
preferably may comprise 12 to 17 % by weight of the epoxy resin.
The epoxy resin may comprise bisphenol A epoxy resin, bisphenol F epoxy
5 resin, or a combination of bisphenol A epoxy resin and bisphenol F epoxy resin. The
epoxy resin may further comprise an epoxy functionalised reactive diluent, or a
plurality of different epoxy functionalised reactive diluents. The epoxy resin may
comprise bisphenol A epoxy resin, bisphenol F epoxy resin, or a combination of
bisphenol A epoxy resin and bisphenol F epoxy resin, and an epoxy functionalised
10 reactive diluent. The epoxy resin may comprise bisphenol A epoxy resin, bisphenol F
epoxy resin, or a combination of bisphenol A epoxy resin and bisphenol F epoxy
resin, and a plurality of different epoxy functionalised reactive diluents.
The mixture may comprise 5 to 15 % by weight of the bisphenol A epoxy
15 resin, bisphenol F epoxy resin, or a combination of bisphenol A epoxy resin and
bisphenol F epoxy resin. Preferably the mixture may comprise 9 to 12 % by weight of
the bisphenol A epoxy resin, bisphenol F epoxy resin, or a combination of bisphenol
A epoxy resin and bisphenol F epoxy resin. The mixture may comprise 1 to 10 % by
weight of the epoxy functionalised reactive diluent or the plurality of different epoxy
20 functionalised reactive diluents, and preferably may comprise 3 to 5 % by weight of
the epoxy functionalised reactive diluent or the plurality of different epoxy
functionalised reactive diluents.
The cross-linker for curing the epoxy resin may comprise a monomeric amine,
25 a polymeric amine, or an anhydride curative. The cross-linker for curing the epoxy
resin may be isophorone diamine. The mixture may comprise 1.5 to 6 % by weight of
the cross-linker for curing the epoxy resin, and preferably may comprise 2 to 4 % by
weight of the cross-linker for curing the epoxy resin.
30 The mixture may comprise 45 to 75 % by weight of the intumescent package,
and preferably may comprise 50 to 65 % by weight of the intumescent package.
5
The intumescent package may comprise a phosphorus containing compound, a
gas source, and a carbon source. The intumescent package may comprise a
phosphorus containing compound and a gas source. Possibly, the intumescent
5 package does not comprise a carbon source. The intumescent package may comprise
an infrared blocker. Possibly, in some examples of the disclosure the intumescent
package does not comprise boric acid or borate salts. In other examples of the
disclosure, the intumescent package may comprise boric acid or borate salts.
10 The mixture may comprise 25 to 65 % by weight of the phosphorus containing
compound, and preferably may comprise 30 to 45 % by weight of the phosphorus
containing compound. The phosphorus containing compound may comprise a fire
retardant comprising a phosphate group, a phosphite group, or phosphonate group.
Possibly, the fire retardant comprising a phosphate group is ammonium
15 polyphosphate, triphenyl phosphate, or melamine polyphosphate. The phosphorous
containing compound may comprise ammonium polyphosphate.
The mixture may comprise 5 to 30 % by weight of the gas source, and
preferably may comprise 10 to 20 % by weight of the gas source. The gas source may
20 comprise melamine, tris-(2-hydroxyethyl) isocyanurate (THEIC), or boric acid. The
gas source may comprise melamine.
The mixture may comprise 0.1 to 15 % by weight of the carbon source, and
preferably may comprise 1 to 5 % by weight of the carbon source. The carbon source
25 may comprise pentaerythritol or dipentaerythritol.
The mixture may comprise 1 to 15 % by weight of the infrared blocker, and
preferably may comprise 1.5 to 5 % by weight of the infrared blocker. The infrared
blocker may comprise titanium dioxide.
30
6
The mixture may comprise reinforcing fibres. The mixture may comprise 1 to
6 % by weight of the reinforcing fibres, and preferably may comprise 2 to 3 % by
weight of the reinforcing fibres. The reinforcing fibres may comprise basalt fibres,
ceramic fibres, carbon fibres, mineral fibres or glass fibres, and may be of any length
5 between 50µm to 15mm. The ceramic fibres may comprise enfil ceramic fibres or
lapinus fibres.
In other examples, the mixture does not comprise reinforcing fibres.
10 The mixture may comprise a rheology modifier. The mixture may comprise
0.1 to 4 % by weight of the rheology modifier, and preferably may comprise 0.1 to 2
% by weight of the rheology modifier. The rheology modifier may comprise an
organoclay, fumed silica, fibres, liquid rheological additives, or hollow glass
microspheres. The organoclay may comprise garamite.
15
The mixture may comprise a moisture scavenger. The moisture scavenger
may comprise molecular sieves or vinyl silane. The molecular sieves may be
synthetic zeolite or natural zeolite. The mixture may comprise 0.01 to 4 % by weight
of the moisture scavenger, and preferably may comprise 0.1 to 1 % by weight of the
20 moisture scavenger.
The mixture may comprise a reactive diluent. The reactive diluent may
comprise vegetable oil. The vegetable oil may comprise castor oil. The mixture may
comprise 0.1 to 5 % by weight of the reactive diluent, and preferably may comprise
25 0.1 to 1 % by weight of the reactive diluent.
The mixture may comprise a solvent. The solvent may comprise xylene,
dimethyl carbonate, or benzyl alcohol. The mixture may comprise 0.01 to 15 % by
weight of the solvent, and preferably may comprise 1 to 9 % by weight of the solvent.
30
7
The mixture may comprise a wetting or dispersing aid. The wetting or
dispersing aid may comprise organosilane or alkoxy siloxane. The mixture may
comprise 0.01 to 3 % by weight of the wetting or dispersing aid, and preferably may
comprise 0. 1 to 1.5 % by weight of the wetting or dispersing aid.
5
The mixture may comprise a boron containing compound. The boron
containing compound may comprise zinc borate, boric acid, or boric oxide. The
mixture may comprise 1 to 10 % by weight of the boron containing compound, and
preferably may comprise 3 to 7 % by weight of the boron containing compound.
10
Possibly, the mixture does not comprise plasticiser.
According to various, but not necessarily all, examples of the disclosure there
is provided a method, wherein the method comprises:
15 mixing a silane-terminated polymer, a cross-linker for curing the silaneterminated polymer, an epoxy resin, a cross-linker for curing the epoxy resin, and an
intumescent package;
allowing the mixture to cure to provide an intumescent coating material.
20 Possibly the method comprises providing the mixture as a two-part mixture.
Possibly, the epoxy resin and the intumescent package are provided in a first
part of the two-part mixture, and the silane-terminated polymer, the cross-linker for
curing the silane-terminated polymer, and the cross-linker for curing the epoxy resin
25 are provided in a second part of the two-part mixture, wherein the method comprises
mixing the first and second parts and allowing the mixture of the first and second
parts to cure to provide an intumescent coating material.
The mixture may be allowed to cure by exposure to an atmosphere which
30 comprises moisture. The mixture may be allowed to cure by exposure to moisture
already present in the mixture, which moisture may be already present in the
8
intumescent package. The mixture may be allowed to cure at ambient temperature,
that is, any temperature between 5°C and 50°C. To reduce cure time, the mixture may
be allowed to cure at elevated temperatures, that is, above 50°C.
5 According to various, but not necessarily all, examples of the disclosure there
is provided an intumescent coating material, wherein the intumescent coating material
is the cured reaction product of a mixture comprising a silane-terminated polymer, a
cross-linker for curing the silane-terminated polymer, an epoxy resin, a cross-linker
for curing the epoxy resin, and an intumescent package.
10
According to various, but not necessarily all, examples of the disclosure there
is provided a body of intumescent coating material, wherein the body of intumescent
coating material is the cured reaction product of a mixture comprising a silaneterminated polymer, a cross-linker for curing the silane-terminated polymer, an epoxy
15 resin, a cross-linker for curing the epoxy resin, and an intumescent package.
According to various, but not necessarily all, examples of the disclosure there
is provided an intumescent coating for protecting a substrate, the intumescent coating
comprising an intumescent coating material, wherein the intumescent coating material
20 is the cured reaction product of a mixture comprising a silane-terminated polymer, a
cross-linker for curing the silane-terminated polymer, an epoxy resin, a cross-linker
for curing the epoxy resin, and an intumescent package.
The intumescent coating may comprise a plurality of layers of the intumescent
25 coating material.
The intumescent coating may comprise a mesh. The mesh may be provided
between respective layers of the intumescent coating material. The mesh may
comprise stainless steel, basalt, silica, carbon or glass fibre.
30
Alternatively, the intumescent coating may not comprise a mesh.
9
The substrate may be metallic or non-metallic. The substrate may comprise a
non-metallic coating, and the intumescent coating is provided on the non-metallic
coating. The non-metallic coating may be an anti-corrosion coating.
5
According to various, but not necessarily all, examples of the disclosure there
is provided a method of protecting a substrate, the method comprising:
applying an intumescent coating material to the substrate, wherein the
intumescent coating material is the cured reaction product of a mixture comprising a
10 silane-terminated polymer, a cross-linker for curing the silane-terminated polymer, an
epoxy resin, a cross-linker for curing the epoxy resin, and an intumescent package.
The substrate may be metallic or non-metallic.
15 In some examples, the method may comprise coating the substrate with the
mixture and allowing the mixture to cure to provide an intumescent coating
comprising the intumescent coating material.
The mixture curable to provide an intumescent coating material may be
20 applied to a non-metallic coating on the substrate. The non-metallic coating may be an
anti-corrosion coating.
In other examples, the method may comprise applying a body of intumescent
coating material to the substrate to provide an intumescent coating comprising the
25 intumescent coating material, wherein the body of intumescent coating material is the
cured reaction product of the mixture. The body of intumescent coating material may
be a sheet of intumescent coating material.
The body of intumescent coating material may be applied to a non-metallic
30 coating on the substrate. The non-metallic coating may be an anti-corrosion coating.
10
The method may comprise providing the substrate with a plurality of layers of
the intumescent coating material. The method may comprise providing a mesh
between respective layers of the intumescent coating material. The mesh may
comprise stainless steel, basalt, silica, carbon or glass fibre.
5
The method may comprise applying a top seal to the intumescent coating. The
top seal may provide weather protection and/or be decorative.
According to various, but not necessarily all, examples of the disclosure there
10 is provided a protected substrate, the substrate comprising an intumescent coating
comprising an intumescent coating material, wherein the intumescent coating material
is the cured reaction product of a mixture comprising a silane-terminated polymer, a
cross-linker for curing the silane-terminated polymer, an epoxy resin, a cross-linker
for curing the epoxy resin, and an intumescent package.
15
The substrate may be metallic or non-metallic. The substrate may comprise a
non-metallic coating, and the intumescent coating is provided on the non-metallic
coating. The non-metallic coating may be an anti-corrosion coating.
20 According to various, but not necessarily all, examples of the disclosure there
may be provided examples as claimed in the appended claims.
BRIEF DESCRIPTION
25 For a better understanding of various examples that are useful for
understanding the detailed description, reference will now be made by way of
example only.
DETAILED DESCRIPTION
30
11
Examples of mixtures according to the disclosure (E1 to E4) are provided in
Table 1 below, along with a comparative example (C1).
5
Table 1
Component Specific example of
component
E1
(wt%)
E2
(wt%)
E3
(wt%)
E4
(wt%)
C1
(wt%)
silane-terminated
polymer
silane-terminated
polyether (trade
name Geniosil STPE10 available from
Wacker)
16.44 19.58 15.12 14.1 16.89
cross-linker for
curing the silaneterminated polymer
amino silane 1.66 1.96 1.52 1.41 1.64
epoxy resin bisphenol A epoxy
resin (trade name
DER331 available
from DOW) and
epoxy functionalised
reactive diluent
(trade name
DER732P available
from DOW)
16.44 13.04 15.12 14.1 0
cross-linker for
curing the epoxy
Isophorone diamine
(IPD)
3.25 2.57 3 2.85 0
12
resin
phosphorus
containing
compound
ammonium
polyphosphate
41.29 39.11 35.37 37.23 36.5
gas source melamine 14.45 15.32 12.37 12.98 12.78
carbon source pentaerythritol 1.99 0.99 3.69 3.88 10.93
infrared blocker titanium dioxide 1.99 3.96 3.69 3.88 10.93
reinforcing fibres enfil ceramic fibres 2.49 2.48 3.67 0 2.51
rheology modifier garamite 0 0.99 0.92 0.25 0
plasticiser (nonreactive diluent)
bis(2-Ethylhexyl)
adipate (DOA) and
triethyl phosphate
(TEP)
0 0 0 0 7.82
solvent xylene 0 0 0 8.1 0
moisture scavenger molecular sieves 0 0 0 0 0
wetting/dispersing
aid
organosilane 0 0 0 1.01 0
reactive diluent vegetable oil 0 0 0 0.25 0
boron containing
compound
zinc borate 0 0 5.53 0 0
As exemplified in Table 1, examples of the disclosure provide a mixture
curable to provide an intumescent coating material. The mixture comprises a silaneterminated polymer, a cross-linker for curing the silane-terminated polymer, an epoxy
5 resin, a cross-linker for curing the epoxy resin, and an intumescent package. An
intumescent package may otherwise be known as an intumescent ingredient.
Some examples of the disclosure do not comprise plasticisers. A plasticiser is
a non-reactive diluent.
10
13
In some examples of the disclosure, the intumescent package comprises a
phosphorus containing compound, a gas source, and a carbon source. The
intumescent package may also comprise an infrared blocker. In some examples, the
carbon of the intumescent package may be provided by the carbon content of the
5 polymer system.
In examples 1 (E1), 3 (E3) and 4 (E4) the ratio of silane-terminated polymer to
epoxy resin is 1:1. In example 2 (E2), the ratio of silane-terminated polymer to epoxy
resin is 0.6 to 0.4. Ratios are calculated on the basis of % by weight. Accordingly, in
10 example 2 the curable mixture comprises 19.58 % by weight of silane-terminated
polymer and 13.04 % by weight of epoxy resin, which is a ratio of 0.6 to 0.4. In other
examples, the ratio of silane-terminated polymer to epoxy resin may be from 0.75 to
0.25 to 0.25 to 0.75.
15 The mixture may comprise 1.5 to 6 % by weight of the cross-linker for curing
the epoxy resin, and 1 to 3 % by weight of the cross-linker for curing the silaneterminated polymer. However, the mixture may comprise an amount sufficient to
cure the epoxy resin and silane-terminated polymer.
20 Examples of the disclosure also provide a method. The method comprises
mixing a silane-terminated polymer, a cross-linker for curing the silane-terminated
polymer, an epoxy resin, a cross-linker for curing the epoxy resin, and an intumescent
package. The method comprises allowing the mixture to cure to provide an
intumescent coating material. Accordingly, examples of the disclosure also provide
25 an intumescent coating material, that is, the reaction product that results from curing
of the curable mixture. The reaction product that results from curing of the curable
mixture may be referred to as a cured intumescent coating material. The cured
intumescent coating material is a hybrid polymer system in that it comprises the cured
polymer reaction products of two different materials, namely: silane-terminated
30 polymer and epoxy resin.
14
In some examples, the curable mixture may also comprise reinforcing fibres,
for instance E1, E2 and E3 in Table 1 above.
Reinforcing fibres support the char which forms when the intumescent
5 coating material expands when subjected to a fire event. The char may have a
thickness many times the thickness of the intumescent coating. The protective char
acts as a physical barrier insulating the substrate and therefore delaying the effects of
a fire and slowing the rate of temperature increase of the coated substrate. This
therefore protects the substrate from failing or delays the occurrence of failure.
10
The curable mixtures of examples E1, E2 and E3, once cured, provide an
intumescent coating material suitable for protecting substrates in a hydrocarbon
facility, for instance, when provided around pipework, valves, I-beams, and other
process components and structural members. In such applications the intumescent
15 coating thickness may be from 4 to 18 mm, and more particularly may be from 8 to 12
mm. In such examples, reinforcing fibres are required to support the structural
integrity of the relatively thick char which forms when the intumescent coating
material expands when subjected to a fire event. Furthermore, the presence of
reinforcing fibres in the mixture allows a relatively thick coating to be applied more
20 quickly because of the increased viscosity of the mixture.
In some examples, the curable mixture does not comprise reinforcing fibres,
for instance, example 4 (E4) in Table 1 above. The curable mixture of E4, once
cured, provides an intumescent coating material suitable for substrates used in
25 transportation, for instance, automotive components and structural members of
vehicles. In such applications the intumescent coating thickness may be from 0.1 to 2
mm, and more particularly may be from 0.3 to 1 mm. In such applications the
thickness of the intumescent coating (and thickness of the resulting char) may be less
than for applications in hydrocarbon facilities because the effects of a fire need be
30 delayed for less time. Accordingly, in such examples reinforcing fibres may not be
required to support the structural integrity of the relatively thin char.
15
In automotive applications, a relatively thin intumescent coating reduces
weight and thus improves fuel economy. The absence of reinforcing fibres further
reduces the weight of the intumescent coating.
5
Furthermore, space may be limited around substrates in automotive
applications, thus a relatively thin intumescent coating is required.
The application of a relatively thin intumescent coating, for example by
10 spraying, may be hindered by the presence of reinforcing fibres which increase the
viscosity of the mixture, making it more difficult to spray onto a substrate and to
provide a uniform thickness.
To facilitate spraying of the mixture and to enable the application of a uniform
15 thickness, example mixtures may comprise a solvent, a wetting or dispersing aid
and/or a reactive diluent. These additives are particularly beneficial where a
relatively thin intumescent coating is required. Such additives reduce viscosity, for
instance. In examples of the disclosure, a reduction in viscosity is achieved without
plasticisers.
20
In some examples, the curable mixture may also comprise a rheology
modifier to optimise flow properties of the mixture, for instance E2, E3 and E4 in
Table 1 above.
25 In some examples, for instance E3 in Table 1 above, the mixture comprises a
boron containing compound to further improve char strength.
In some examples of the disclosure, the mixture curable to provide an
intumescent coating material is a two-part mixture. In some examples, a first part
30 comprises the epoxy resin and the intumescent package, and the second part
comprises the silane-terminated polymer, the cross-linker for curing the silane-
16
terminated polymer, and the cross-linker for curing the epoxy resin. Additional
additives may be provided in the first and/or second parts.
A moisture scavenger may be provided in the first and/or second parts to
5 improve stability of the uncured mixture.
The first and second parts are mixed together to initiate curing, which
subsequently provides the intumescent coating material as a cured reaction product.
The first part may be prepared by mixing in a high-speed disperser. The second part
10 may be prepared by mixing in a high-speed disperser. In some examples, the first and
second parts are subsequently mixed and allowed to cure at ambient temperature, that
is any temperature between 5°C and 50°C, in the presence of atmospheric moisture.
The pot life is around 20 to 30 minutes. Full cure is achieved after 12 hours.
15 The pot life can be tailored, for example, by selecting specific ratios of αsilane-terminated polyether and γ-silane-terminated polyether. The higher the γ-silane
content, the slower the pot life of the material.
The silyl groups of silane-terminated polyethers are coupled to the ends of the
20 polyether backbone, and generally via an alkylene unit and a urethane group. The
alkylene unit can either be a methylene group, in which case it is an α-silaneterminated polyether, or a propylene group, in which case it is a γ-silane-terminated
polyether.
25 Accordingly, in some examples the silane-terminated polyether is a mixture of
α-silane-terminated polyether and γ-silane-terminated polyether. In other examples,
the silane-terminated polyether is α-silane-terminated polyether, or alternatively γsilane-terminated polyether
30 Alternatively, or additionally, the pot life can further be tailored by selecting
an epoxy curing agent which gives the desired pot life.
17
In some examples, the mixture is allowed to cure by exposure to moisture
already present in the mixture (internal moisture). The moisture may be already
present in the intumescent package, that is, the powders of the intumescent package.
5 This allows the mixture to cure in less humid environments. In some examples, the
mixture is allowed to cure by exposure to atmospheric moisture and moisture already
present in the mixture.
Silane-terminated polymer and the cross-linker for curing the silane10 terminated polymer can be provided in the same part, provided moisture is not
present. The epoxy resin and the cross-linker for curing the epoxy resin are provided
in separate parts, as otherwise the epoxy resin would cure. Surprisingly, the crosslinker for curing the epoxy resin has been found not to cure the silane-terminated
polymer, and these materials can therefore be provided in the same part. In examples
15 where the mixture comprises reinforcing fibres and rheology modifiers, these
materials may be provided in the second part as otherwise the first part may be too
viscous.
Examples of the disclosure also provide an intumescent coating for protecting
20 a substrate. The intumescent coating comprises an intumescent coating material as
described above. Examples of the disclosure also provide a method of protecting a
substrate.
In some examples, the method comprises coating the substrate with a mixture
25 as described above which is curable to provide an intumescent coating material as
described above. The method also comprises allowing the mixture to cure to provide
an intumescent coating comprising the intumescent coating material.
In practice, the mixture described above is applied to the substrate, for
30 example by spraying, brushing, rolling, trowelling or moulding. In some examples,
the intumescent coating may comprise a plurality of layers of the intumescent coating
18
material. Accordingly, in such examples a first layer of intumescent coating material
is applied to the substrate, the mixture is allowed to cure, or at least partially cure, and
then a second layer of intumescent coating material is applied on top of the first layer.
Subsequent additional layers may be applied. In some examples, the intumescent
5 coating comprises a mesh. The mesh is provided between respective layers of the
intumescent coating material. The mesh may comprise stainless steel, basalt, silica,
carbon or glass fibre.
In some examples, the substrate is a metallic substrate, for example, structural
10 steel or aluminium. The metallic substrate may comprise a non-metallic coating, such
as an anti-corrosion coating. Accordingly, in examples of the disclosure the curable
mixture is either applied directly to the metallic substrate or applied to the nonmetallic coating of the metallic substrate.
15 In other examples the substrate may be non-metallic. Example non-metallic
substrates include: plastics, polymers, polymeric materials, composites, foams,
fibrous insulation materials, other passive insulation materials, concrete and other
construction materials, or materials used in transportation, for instance automotive
components and structural members of vehicles.
20
As an alternative to coating the substrate with a curable mixture, in some
examples the method may comprise applying a body of intumescent coating material
to the substrate to provide an intumescent coating comprising the intumescent coating
material, wherein the body of intumescent coating material is the cured reaction
25 product of the mixture. The body of intumescent coating material may be a sheet,
film or panel of intumescent coating material, that is, a pre-cured film, sheet or panel.
Multiple bodies (sheets, films or panels) of intumescent coating material may be
applied to the substrate to provide an intumescent coating comprising a plurality of
layers of the intumescent coating material.
30
19
In some examples, the body of intumescent coating material may be applied to
an area bridging two or more separate substrates. For example, the body of
intumescent coating material may be applied to an area comprising a joint between
two separate substrates.
5
In some examples, the method also comprises applying a top seal to the
intumescent coating. The top seal may provide weather protection and/or be
decorative.
10 Examples of the disclosure also provide a protected substrate. The substrate
comprises an intumescent coating. The intumescent coating comprises an
intumescent coating material, wherein the intumescent coating material is the cured
reaction product of the mixture described above. In some examples, the protected
substrate comprises a non-metallic layer underlying the intumescent coating, which
15 may be an anti-corrosion layer and/or a top seal overlying the intumescent coating,
which may provide weather protection and/or be decorative.
There is thus described a mixture curable to provide an intumescent coating
material, a method of providing an intumescent coating material, an intumescent
20 coating material, an intumescent coating for protecting a substrate, a method of
protecting a substrate, and a protected substrate with a number of advantages as
detailed above and as follows.
In examples of the disclosure, the combination of silane-terminated polymer
25 and epoxy resin, once cured, provides an intumescent coating material with an
optimum balance of passive fire resistance, flexibility, toughness, and adhesiveness
for use as an intumescent coating (or as a part of an intumescent coating) around
substrates such as pipework, valves, I-beams and other process components, structural
members, for example in hydrocarbon facilities on or off shore.
30
20
In examples of the disclosure, the combination of silane-terminated polymer
and epoxy resin, once cured, also provides an intumescent coating material with an
optimum balance of passive fire resistance, flexibility, toughness, and adhesiveness
for use as an intumescent coating (or as a part of an intumescent coating) around
5 substrates used in transportation, for instance automotive components and structural
members of vehicles. An intumescent coating may be provided on a substrate
covering an area used to accommodate components of a vehicle which may present a
fire risk, for instance batteries.
10 In such automotive applications, even though the intumescent coating may be
relatively thin it still provides the desirable properties as described above.
Without being bound by theory, subsequently cured silane-terminated polymer
contributes significantly to the flexibility of the intumescent coating material, and
15 particularly to cold flexibility. For example, epoxy based intumescent coating
materials (which do not comprise cured silane-terminated polymer) cannot withstand
movement of a substrate, for example, a rig, in cold climates (for example at or below
-50°C, such as encountered in the Arctic circle). Such known materials therefore
have a tendency to crack and/or fall off. Intumescent coating materials according to
20 examples of the disclosure demonstrate improved flexibility on account of the
presence of cured silane-terminated polymer. Accordingly, intumescent coating
material according to examples of the disclosure may better move with the substrate,
and therefore do not crack and/or fall off the substrate.
25 Known materials based on silane-terminated polymer, but which do not
comprise epoxy resin and may instead comprise a plasticiser, may be easily damaged
in use, for instance if such materials are impacted, because of a relatively low
toughness. Intumescent coating materials according to examples of the disclosure are
less likely to be damaged in use because the presence of cured epoxy resin
30 significantly increases toughness.
21
The presence of cured epoxy resin in intumescent coating materials according
to the disclosure also improves adhesion of the intumescent coating material to other
materials, for example, to anti-corrosion coatings and top seals if present.
5 Furthermore, the presence of epoxy resin in mixtures according to the
disclosure permits a significant amount of intumescent package to be provided in the
mixture, which leads to improved fire resistance properties in the subsequently cured
intumescent coating material.
10 Furthermore, intumescent coating materials according to examples of the
disclosure demonstrate excellent environmental stability.
Furthermore, the use of epoxy resin (i.e. reactive epoxy) in the curable
reaction mixture instead of plasticiser considerably improves durability and reduces
15 moisture absorption of the resulting cured intumescent material.
When subjected to a fire event an intumescent coating according to examples
of the disclosure expands to form a protective char. The protective Char acts as a
physical barrier insulating the substrate and therefore delaying the effects of a fire and
20 slowing the rate of temperature increase of the coated substrate. This therefore
protects the substrate from failing or delays the occurrence of failure, thereby
providing additional time to permit evacuation, for example, of personnel from a
hydrocarbon facility or of the occupants of a vehicle and/or fire fighting.
25 Although embodiments of the present invention have been described in the
preceding paragraphs with reference to various examples, it should be appreciated that
modifications to the examples given can be made without departing from the scope of
the invention as claimed.
30 Features described in the preceding description may be used in combinations
other than the combinations explicitly described.

Although functions have been described with reference to certain features,
those functions may be performable by other features whether described or not.
5 Although features have been described with reference to certain embodiments,
those features may also be present in other embodiments whether described or not.
The term “comprise” is used in this document with an inclusive not an
exclusive meaning. That is any reference to X comprising Y indicates that X may
10 comprise only one Y or may comprise more than one Y. If it is intended to use
“comprise” with an exclusive meaning then it will be made clear in the context by
referring to “comprising only one…” or by using “consisting”.
In this brief description, reference has been made to various examples. The
15 description of features or functions in relation to an example indicates that those
features or functions are present in that example. The use of the term “example” or
“for example” or “may” in the text denotes, whether explicitly stated or not, that such
features or functions are present in at least the described example, whether described
as an example or not, and that they can be, but are not necessarily, present in some of
20 or all other examples. Thus “example”, “for example” or “may” refers to a particular
instance in a class of examples. A property of the instance can be a property of only
that instance or a property of the class or a property of a sub-class of the class that
includes some but not all of the instances in the class. It is therefore implicitly
disclosed that features described with reference to one example but not with reference
25 to another example, can where possible be used in that other example but does not
necessarily have to be used in that other example.
Whilst endeavoring in the foregoing specification to draw attention to those
features of the invention believed to be of particular importance it should be
30 understood that the Applicant claims protection in respect of any patentable feature or
23
combination of features hereinbefore referred to and/or shown in the drawings
whether or not particular emphasis has been placed thereon.
24
WE CLAIM:
1. A mixture curable to provide an intumescent coating material, wherein the mixture
comprises a silane-terminated polymer, a cross-linker for curing the silane-terminated
5 polymer, an epoxy resin, a cross-linker for curing the epoxy resin, and an intumescent
package.
2. A mixture according to claim 1, wherein the ratio of silane-terminated polymer to
epoxy resin is from 0.75 to 0.25:0.25 to 0.75.
10
3. A mixture according to claims 1 or 2, wherein the ratio of silane-terminated
polymer to epoxy resin is from 0.6 to 0.4:0.4 to 0.6.
4. A mixture according to any of the preceding claims, wherein the ratio of silane15 terminated polymer to epoxy resin is 1:1.
5. A mixture according to any of the preceding claims, wherein the mixture curable to
provide an intumescent coating material is a two-part mixture.
20 6. A mixture according to claim 5, wherein a first part of the two-part mixture
comprises the epoxy resin and the intumescent package, and a second part of the twopart mixture comprises the silane-terminated polymer, the cross-linker for curing the
silane-terminated polymer, and the cross-linker for curing the epoxy resin.
25 7. A mixture according to any of the preceding claims, wherein the silane-terminated
polymer comprises silane-terminated polyether or silane-terminated polyurethane.
8. A mixture according to any of the preceding claims, wherein the mixture comprises
10 to 30 % by weight of the silane-terminated polymer.
30
25
9. A mixture according to any of the preceding claims, wherein the mixture comprises
14 to 20 % by weight of the silane-terminated polymer.
5 10. A mixture according to any of the preceding claims, wherein the mixture
comprises 1 to 3 % by weight of the cross-linker for curing the silane-terminated
polymer.
11. A mixture according to any of the preceding claims, wherein the mixture
10 comprises 1.4 to 2 % by weight of the cross-linker for curing the silane-terminated
polymer.
12. A mixture according to any of the preceding claims, wherein the mixture
comprises 6 to 25 % by weight of the epoxy resin.
15
13. A mixture according to any of the preceding claims, wherein the mixture
comprises 12 to 17 % by weight of the epoxy resin.
14. A mixture according to any of the preceding claims, wherein the epoxy resin
20 comprises bisphenol A epoxy resin, bisphenol F epoxy resin, or a combination of
bisphenol A epoxy resin and bisphenol F epoxy resin.
15. A mixture according to claim 14, wherein the mixture comprises 5 to 15 % by
weight of the bisphenol A epoxy resin, bisphenol F epoxy resin, or a combination of
25 bisphenol A epoxy resin and bisphenol F epoxy resin.
16. A mixture according to claims 14 or 15, wherein the mixture comprises 9 to 12 %
by weight of the bisphenol A epoxy resin, bisphenol F epoxy resin, or a combination
of bisphenol A epoxy resin and bisphenol F epoxy resin.
30
26
17. A mixture according to any of claims 14 to 16, wherein the epoxy resin further
comprise an epoxy functionalised reactive diluent.
18. A mixture according to claim 17, wherein the mixture comprises 1 to 10 % by
5 weight of the epoxy functionalised reactive diluent.
19. A mixture according to claims 17 or 18, wherein the mixture comprises 3 to 5 %
by weight of the epoxy functionalised reactive diluent.
10 20. A mixture according to any of the preceding claims, wherein the mixture
comprises 45 to 75 % by weight of the intumescent package.
21. A mixture according to any of the preceding claims, wherein the mixture
comprises 50 to 65 % by weight of the intumescent package.
15
22. A mixture according to any of the preceding claims, wherein the intumescent
package comprises a phosphorus containing compound, a gas source, and a carbon
source.
23. A mixture according to claim 22, wherein the mixture comprises 25 to 65 % by
20 weight of the phosphorus containing compound,
24. A mixture according to claims 22 or 23, wherein the mixture comprises 30 to 45
% by weight of the phosphorus containing compound.
25 25. A mixture according to any of claims 22 to 24, wherein the mixture comprises 5 to
30 % by weight of the gas source.
26. A mixture according to any of claims 22 to 25, wherein the mixture comprises 10
to 20 % by weight of the gas source.
30
27
27. A mixture according to any of claims 22 to 26, wherein the mixture comprises 0.1
to 15 % by weight of the carbon source.
28. A mixture according to any of claims 22 to 27, wherein the mixture comprises 1 to
5 5 % by weight of the carbon source.
29. A mixture according to any of the preceding claims, wherein the intumescent
package comprises an infrared blocker.
10 30. A mixture according to claim 29, wherein the mixture comprises 1 to 15 % by
weight of the infrared blocker.
31. A mixture according to claims 29 or 30, wherein the mixture comprises 1.5 to 5 %
by weight of the infrared blocker.
15
32. A mixture according to any of the preceding claims, wherein the mixture
comprises reinforcing fibres.
33. A mixture according to claim 32, wherein the mixture comprises 1 to 6 % by
20 weight of the reinforcing fibres.
34. A mixture according to claims 32 or 33, wherein the mixture comprises 2 to 3 %
by weight of the reinforcing fibres.
25 35. A mixture according to any of claims 1 to 31, wherein the mixture does not
comprise reinforcing fibres.
36. A mixture according to any of the preceding claims, wherein the mixture
comprises a rheology modifier.
30
28
37. A mixture according to claim 36, wherein the mixture comprises 0.1 to 4 % by
weight of the rheology modifier.
38. A mixture according to claims 36 or 37, wherein the mixture comprises 0.1 to 2 %
5 by weight of the rheology modifier.
39. A mixture according to any of the preceding claims, wherein the mixture
comprises a moisture scavenger.
10 40. A mixture according to claim 39, wherein the mixture comprises 0.01 to 4 % by
weight of the moisture scavenger.
41. A mixture according to claims 39 or 40, wherein the mixture comprises 0.1 to 1 %
by weight of the moisture scavenger.
15
42. A mixture according to any of the preceding claims, wherein the mixture
comprises a reactive diluent.
43. A mixture according to claim 42, wherein the mixture comprises 0.1 to 5 % by
20 weight of the reactive diluent.
44. A mixture according to claims 42 or 43, wherein the mixture comprises 0.1 to 1 %
by weight of the reactive diluent.
25 45. A mixture according to any of the preceding claims, wherein the mixture
comprises a solvent.
46. A mixture according to claim 45, wherein the mixture comprises 0.01 to 15 % by
weight of the solvent.
30
29
47. A mixture according to claims 45 or 46, wherein the mixture comprises 1 to 9 %
by weight of the solvent.
48. A mixture according to any of the preceding claims, wherein the mixture
5 comprises a wetting or dispersing aid.
49. A mixture according to claim 48, wherein the mixture comprises 0.01 to 3 % by
weight of the wetting or dispersing aid.
10 50. A mixture according to claims 48 or 49, wherein the mixture comprises 0.1 to 1.5
% by weight of the wetting or dispersing aid.
51. A mixture according to any of the preceding claims, wherein the mixture
comprises a boron containing compound.
15
52. A mixture according to claim 51, wherein the mixture comprises 1 to 10 % by
weight of the boron containing compound.
53. A mixture according to claims 51 or 52, wherein the mixture comprises 3 to 7 %
20 by weight of the boron containing compound.
54. A method, wherein the method comprises:
mixing a silane-terminated polymer, a cross-linker for curing the silaneterminated polymer, an epoxy resin, a cross-linker for curing the epoxy resin, and an
25 intumescent package;
allowing the mixture to cure to provide an intumescent coating material.
55. A method according to claim 54, wherein the method comprises providing the
mixture as a two-part mixture.
30
30
56. A method according to claim 55, wherein the epoxy resin and the intumescent
package are provided in a first part of the two-part mixture, and the silane-terminated
polymer, the cross-linker for curing the silane-terminated polymer, and the crosslinker for curing the epoxy resin are provided in a second part of the two-part mixture,
5 wherein the method comprises mixing the first and second parts and allowing the
mixture of the first and second parts to cure to provide an intumescent coating
material.
57. A body of intumescent coating material, wherein the body of intumescent coating
10 material is the cured reaction product of a mixture comprising a silane-terminated
polymer, a cross-linker for curing the silane-terminated polymer, an epoxy resin, a
cross-linker for curing the epoxy resin, and an intumescent package.
58. An intumescent coating for protecting a substrate, the intumescent coating
15 comprising an intumescent coating material, wherein the intumescent coating material
is the cured reaction product of a mixture comprising a silane-terminated polymer, a
cross-linker for curing the silane-terminated polymer, an epoxy resin, a cross-linker
for curing the epoxy resin, and an intumescent package.
20 59. An intumescent coating according to claim 58, wherein the intumescent coating
comprises a plurality of layers of the intumescent coating material.
60. An intumescent coating according to claims 58 or 59, wherein the intumescent
coating comprises a mesh.
25
61. An intumescent coating according to claim 60 when dependent on claim 59,
wherein the mesh is provided between respective layers of the intumescent coating
material.
30 62. A protected substrate, the substrate comprising an intumescent coating comprising
an intumescent coating material, wherein the intumescent coating material is the cured
31
reaction product of a mixture comprising a silane-terminated polymer, a cross-linker
for curing the silane-terminated polymer, an epoxy resin, a cross-linker for curing the
epoxy resin, and an intumescent package.
5 63. A protected substrate according to claim 62, wherein the substrate comprises a
non-metallic coating, and the intumescent coating is provided on the non-metallic
coating.
64. A protected substrate according to claim 63, wherein the non-metallic coating is
10 an anti-corrosion coating.
65. A method of protecting a substrate, the method comprising:
applying an intumescent coating material to the substrate, wherein the
intumescent coating material is the cured reaction product of a mixture comprising a
15 silane-terminated polymer, a cross-linker for curing the silane-terminated polymer, an
epoxy resin, a cross-linker for curing the epoxy resin, and an intumescent package.

66. A method according to claim 65, wherein the method comprises coating the
substrate with the mixture and allowing the mixture to cure to provide an intumescent
20 coating comprising the intumescent coating material.
67. A method according to claim 65, wherein the method comprises applying a body
of intumescent coating material to the substrate to provide an intumescent coating
comprising the intumescent coating material, wherein the body of intumescent coating
25 material is the cured reaction product of the mixture.
68. A method according to any of claims 65 to 67, wherein the method comprises
providing the substrate with a plurality of layers of the intumescent coating material.

69. A method according to claim 68, wherein the method comprises providing a mesh
between respective layers of the intumescent coating material.