Fire protective flexible composite insulating system

Flexible composite materials which are suitable for use as fire barriers for either static or dynamic joints are cost effective and easy to install. In one preferred embodiment the flexible composite includes (a) a first layer material having first and second major surfaces, the first layer material including inorganic fibers and a binder in the form of a flexible mat; (b) a second layer material adhered to the first major surface of the first layer material, the second layer material consisting essentially of metal foil, the second layer material having a melting temperature of at least about 350.degree. C.; and (c) a third layer adhered to the second major surface of the first layer material, the third layer material including an intumescent fire retardant composite material.

FIELD OF THE INVENTION 
This invention pertains to flexible composite materials suitable for use in 
deterring the spread of fire, smoke, and fumes as may happen in a fire in 
a multi-floor building. 
BACKGROUND ART 
Fire, smoke, and fumes in confined spaces, such as multi-floor buildings, 
can be extremely life threatening. Frequently, if fire originates in the 
space between a floor and ceiling of such a structure, the fire, and 
resultant smoke and fumes, will tend to spread to other open spaces in the 
building, especially to open spaces above the point of origin of the fire. 
The reasons behind this spread of fire, smoke, and fumes to higher areas 
are varied. The areas between conduits, piping, and the like, and 
floors/ceilings through which they pass, are known as 
"through-penetrations". If not fire protected, through-penetrations offer 
areas of low resistance to fire, smoke, and fumes, and in essence serve as 
"chimneys". These areas may be filled with commercially available fire 
retardant and intumescent putties, caulks, wraps, or mats, known in the 
art as "firestops". Representative firestop products are disclosed in 
product brochure number 98-0701-3508-6 (published 1990) from Minnesota 
Mining and Manufacturing Company (3M). The 3M products are currently known 
under the trade designations "CP 25WB" "CP 25N/S" "CP 25S/L" and "Firedam" 
(caulks); "MPP-4S" and "MPS-2" (moldable putties); "FS-195" and "CS-195" 
(moldable strips); and "Interam" and "Interam E-5" (mats). These products 
are variously described in assignee's U.S. Pat. Nos. 3,916,057; 4,273,879; 
4,305,992; 4,364,210; 4,433,732; and 4,467,577. 
The above firestop products and others have been widely used for reducing 
or eliminating the chimney effect for through-penetrations and pass the 
rigorous American Society of Testing Materials (ASTM) fire endurance test 
(ASTM E-814) after intumescing and charring. However, even if the fire is 
contained in the space between one floor and the next highest floor by a 
firestop, serious hazards remain. This is because many multi-level 
buildings will have joints between exterior walls and floors constructed 
as illustrated in side elevation in FIG. 1. Shown is "vision" or 
"spandrel" (i.e., ornamental) glass 10, which may form the exterior of a 
building. (Alternatively, 10 may be concrete, marble, and the like.) 
Typically, an inorganic fibrous material 12 is installed for thermal 
insulation (referred to in the art as a "curtain wall"). The inorganic 
fibrous material may be glass fiber, mineral wool, and the like. Thermal 
insulation 12 is fastened to a "mullion" 13 (term of art for the metal 
frame system for the exterior glass and thermal insulation) with screws or 
other means as shown at 16 and 18. Also shown is a concrete floor slab 20 
which is typically supported by an I-beam 22. A "safing" material 14 is 
also typically installed, which may be glass fiber, mineral wool, or other 
type of inorganic fibrous material insulation. One or more Z-clips 15 is 
typically provided for mechanically supporting safing 14. 
It is important to note that an air space 24 is left in the construction 
illustrated in FIG. 1, between the mullion, thermal insulation, and the 
vision or spandrel glass (typically about 2.5 cm gap). As heat is 
generated in the interior of the building in the vicinity of such a 
wall/floor joint, if the temperature is high enough, the binder in mineral 
wool insulation will oxidize, exposing the air space 24 to fire, smoke, 
and fumes, and allow the chimney effect discussed above. (Glass fiber 
insulation will begin to disintegrate at about 565.degree. C., causing 
similar problems.) Heat from the fire may then distort the mullion system, 
cause the concrete floor to deform, and may ultimately cause the vision or 
spandrel glass (or other exterior wall material) to shatter. Obviously, 
falling debris present a hazard to people outside of the building, such as 
fire control personnel and on-lookers, and fire hoses may be cut by 
falling glass chards and other debris. Thus, it would be highly 
advantageous to keep the temperature of the thermal insulation as low as 
possible, for all of these reasons. 
As explained by Nicholas, J. D., in "Making Joint Systems Fire-Resistive" 
NFPA Journal, March/April (1991), pp. 98-102, at 100: 
The crucial difference between joints such as those illustrated in FIG. 1! 
and through-penetrations is movement. Firestops are designed for static 
applications because the movement of penetrating items, such as pipes, is 
normally absorbed by bellows joints and directed away from the firestop. 
Thus, the firestop remains relatively static. However, joints do move, 
responding to expansion, contraction, shear, and rotational joint 
movements caused by thermal variations, seismicity, settlement, and wind 
sway . . . If the fire barrier deteriorates, permanently deforms, or 
cannot cycle, it may not be able to maintain its fire rating. (Emphasis 
supplied) 
Note that the terms "firestop" and "fire barrier" have different and 
precise meanings in the art, the former describing materials used in 
through-penetrations and other static joints, the latter used to denote 
materials used in movable (dynamic) joints. 
There is thus a requirement for a flexible composite material which can be 
used in conjunction with conventional thermal insulation to form a system 
which provides not only adequate thermal insulation under static 
conditions, but which also provides the required fire barrier properties 
for dynamic joints such as illustrated in FIG. 1. The present invention is 
drawn toward meeting this need. Currently, as explained by Nicholas at 
page 100, there exists no fire endurance standards for fire barriers since 
standard tests have not been available. 
U.S. Pat. No. 4,977,719 (LaRoche et al.) describes an expansion joint for 
interior or exterior use including a fire barrier comprised of a fire 
resistant inorganic refractory fabric sheet which supports resilient fire 
resistant inorganic refractory fibers. German patent application DE 
3632648 (Figen et al.) describes a rain-proof and fire-resistant movable 
profile system for a freely movable connection of an available building 
wall, especially a wall of an older building, and a butt-jointing 
attachable exterior wall, consisting of three individual profiles which 
can be moved with respect to each other. Neither reference suggests the 
composites, systems, or methods of the present invention. 
SUMMARY OF THE INVENTION 
It has now been determined that wall/floor joints such as those illustrated 
in FIG. 1, and other "dynamic" (subject to movement) joints, may be 
brought into compliance with an equivalent of ASTM E-119 through their 
entire cycle of expansion and contraction. Certain preferred embodiments 
of the novel flexible composite materials and systems of this invention 
provide this long felt need. These preferred embodiments will not only 
pass the rigors of a fire endurance test comparable to ASTM E-119, but 
will also pass the hose stream test of this standard. Construction joints 
(static joints between two floor slabs) would also benefit from these 
constructions; however, as movement is not a problem in this type of 
joint, other preferred flexible composite materials and system embodiments 
within the invention will be sufficient to pass the E-119 test. 
In its broadest embodiment, the invention comprises a flexible composite 
material suitable for use in static joints, the flexible composite 
comprising: 
(a) a first layer of material having first and second major surfaces, the 
first layer material comprising inorganic fibers and a binder in the form 
of a flexible mat; and 
(b) a second layer material adhered to the first major surface of the first 
layer material, the second layer material consisting essentially of metal 
foil adhered to the first layer by an adhesive, the second layer material 
having a melting temperature of at least about 350.degree. C. These 
flexible composite embodiments are suitable for use as a fire barrier in 
static conditions. 
Preferably, when used as a fire barrier for dynamic joints, such as 
wall/floor joints experiencing thermal expansion/contraction cycling, the 
flexible composite material includes a third layer (c) adhered to the 
second major surface of the first layer material, the third layer material 
comprising a flexible intumescent fire retardant composite. This 
embodiment may also be used in static joints. 
In all embodiments of the invention the inorganic fibers of the first layer 
are selected from the group consisting of alumina-silicate fibers, mineral 
wool fibers, glass fibers, and refractory filaments such as 
zirconia-silica fibers and crystalline alumina whiskers. Mixtures of these 
inorganic fibers are also usable within the invention. The first layer may 
optionally include up to about 65 weight percent (More preferably from 
about 40 to about 65 weight %) unexpanded vermiculite. Binders may be 
organic and/or inorganic. 
An alternate embodiment of the flexible composite material of the 
invention, also suitable for use as a fire barrier for static joints, 
comprises: 
(a) a first layer material having first and second major surfaces, the 
first layer material comprising inorganic fibers and a binder in the form 
of a flexible mat, as above described; 
(b) a second layer material adhered to the first major surface of the first 
layer material, the second layer material comprising a flexible 
intumescent fire retardant composite material as above described; 
(c) a third layer adhered to the second layer, the third layer comprising 
inorganic fibers which are the same or different than the first layer as 
above described; and 
(d) a fourth layer adhered to the third layer, the fourth layer comprising 
a flexible intumescent fire retardant composite material. 
Another alternate embodiment of the flexible composite material of the 
invention suitable for use with static joints comprises: 
(a) a first layer material having first and second major surfaces, the 
first layer material comprising inorganic fibers and a binder, formed as a 
flexible mat, as above described; 
(b) second and third layers adhered to the first and second major surfaces 
of the first layer, respectively, the second and third layers comprising 
inorganic fibers which are different from those of the first layer; 
(c) fourth and fifth layers adhered to the second and third layers, 
respectively, the fourth and fifth layers comprising a flexible 
intumescent fire retardant composite material. 
Systems for thermally insulating and providing fire barrier properties for 
an exterior wall and/or an exterior wall/floor joint of a building are 
also presented. All systems of the invention are designed to be installed 
in buildings wherein the wall comprises mullion and exterior material, and 
wherein the floor comprises a material which is rigid at room temperatures 
but experiences deformation due to thermal expansion (especially at fire 
temperatures) and contraction, seismic activity, and the like. 
The first preferred class of systems according to the invention may be 
described generally as "long" versions, since the fire barrier extends the 
entire length of the insulating component. This embodiment of the system 
comprises: 
(a) an insulating component positioned substantially within the shape 
defined by the mullion upon attachment to the mullion and having interior 
and exterior facing surfaces, the insulating component comprising an 
inorganic material capable of providing thermal insulation for the 
building; 
(b) a safing component positioned substantially between an exterior butt 
end of the floor and the insulating component; and 
(c) a fire barrier comprising a flexible composite material, the fire 
barrier having first and second portions, the first portion positioned 
adjacent and substantially parallel to the insulating component, and the 
second portion positioned substantially adjacent the safing component 
upper surface, the second portion having first and second ends, the first 
end attached to the top surface of the butt end of the floor and the 
second end attached to the first portion, and the first portion of the 
fire barrier attached to the mullion, wherein the second portion has at 
least one curved portion which provides slack, thus allowing the fire 
barrier to effectively lengthen and shorten during relative movement of 
the wall and floor. 
A particularly preferred system of this class of systems is the system 
wherein the first portion of the fire barrier has an upper and a lower 
terminus and is positioned substantially adjacent and parallel to the 
interior facing surface of the insulating component. The lower terminus of 
the first portion is attached to the mullion in a fashion which completely 
covers the insulating component. The upper terminus of the first portion 
is attached to the second fire barrier portion. The upper terminus extends 
between the insulating and safing components in this embodiment. The 
second portion most importantly includes an S-shaped curved portion or 
like accumulation which is positioned substantially adjacent the upper 
surface of the safing; intumescent caulk is applied to seal the fire 
barrier to the insulation and to the safing, and the safing is supported 
by one or more Z-clips or similar clips. This system is particularly 
preferable as a retrofit or original installation when the insulating 
component is glass fiber. These "long" versions also prolong the life of 
the exterior glass or other material, as well as the mullion. 
A second, less expensive class of systems for thermally insulating and 
providing fire barrier properties for dynamic exterior wall/floor joints 
of buildings is presented. In this class of systems (which may be 
described generally as "short" versions), the fire barrier is attached to 
that portion of the insulating component positioned above the safing, and 
is also attached to the floor. These systems comprise: 
(a) an insulating component positioned substantially within the shape 
defined by the mullion upon attachment to the mullion and having interior 
and exterior facing surfaces, the insulating component comprising an 
inorganic material capable of providing thermal insulation for the 
building; 
(b) a safing component positioned substantially between an exterior butt 
end of the floor and the insulating component; and 
(c) a fire barrier comprising a single length of flexible composite 
material, the fire barrier having first and second ends, the first end 
positioned substantially adjacent and fastened to the insulating component 
and mullion at a point no lower than the safing, the second end fastened 
to the top surface of the exterior butt end of the floor, wherein the 
flexible composite has at least one curved portion which provides slack to 
allow the fire barrier to effectively lengthen and shorten during relative 
movement between the floor and wall. These embodiments are advantageously 
used when the portion of the insulating component below the safing is 
mineral wool or other high temperature resistant material. The "short" 
fire barriers cannot be employed with glass fiber insulation installed 
below the safing since glass fiber insulation will begin to disintegrate 
at about 565.degree. C., as previously mentioned. (The time-temperature 
curve of the ASTM E-119 test reaches temperatures of about 925.degree. C.) 
A method of making the three layer version of the flexible composite 
materials of the invention is also presented as another aspect of the 
invention. The method includes the steps of 
i) providing a laminate comprising a first layer comprising inorganic 
fibers and a binder formed into a mat, the first layer having on one major 
surface thereof a second layer consisting essentially of metal foil 
adhered to the first layer by an adhesive; 
ii) coating an intumescent precursor solution comprising solvent and an 
intumescent fire retardant material onto the second major surface of the 
first layer to produce a wet coated composite material; and 
iii) exposing the wet coated composite material to conditions sufficient to 
cure the intumescent fire retardant material, thereby forming a flexible 
third layer comprising a the intumescent fire retardant material. 
Preferably the solvent is water or an organic solvent, and the step of 
exposing the wet coated composite material to conditions sufficient to 
cure the intumescent fire retardant material is by the application of 
heat. 
Methods of fireproofing a dynamic wall/joint with the long and short 
systems of the invention are also presented. In some methods, the 
insulation has been previously installed, for example, when an older 
building is to have a fire barrier installed. These are "retrofit" 
methods. 
In one method of installing a long version of the system, insulating 
material is first positioned in the mullion. The flexible composite having 
three layers is then placed substantially adjacent and parallel to the 
surface of the insulation facing the interior of the building, securing 
the lower end of the composite to the mullion, being sure that the 
flexible composite completely covers the lower terminus of the insulation. 
With the intumescent fire retardant side of the composite facing toward 
the interior of the building, the composite is positioned between the 
insulation and safing, after which the composite is accumulated in an "S" 
shape (or the like) on top of the safing. The previously unfastened end of 
the composite is then fastened to the floor slab. Intumescent caulk is 
used to seal the composite to the safing and insulation, as described 
herein. 
The three layer flexible composite materials of the invention, and long and 
short systems employing them, remedy a long felt need to both thermally 
insulate and provide fire barrier properties for dynamic wall/floor 
joints, joints which heretofore have provided chimneys for growing fires 
in multi-level buildings. The other flexible composite materials and 
systems of the invention provide new means to fireproof construction gaps. 
Other advantages of the invention will become apparent from the detailed 
description which follows.

DESCRIPTION OF PREFERRED EMBODIMENTS 
In order to meet the shortcomings in building standards for dynamic joints 
noted by Nicholas, above, I have invented the flexible composites of FIGS. 
2 and 3. Thermal insulation (as shown in FIG. 1 at 12) is required by 
building codes for its thermal insulation and moisture barrier properties 
only. There are currently no codes or standards for fire barrier 
construction for dynamic joints because there has heretofore been no 
method to test dynamic joints for fire safety. 
All flexible composite embodiments of the invention (except embodiment 40 
of FIG. 4) utilize a flexible intumescent fire retardant composite layer 
or layers. The flexible intumescent fire retardant composite preferably 
comprises from about 15 to about 80 weight percent hydrated alkali metal 
silicate, from about 15 to about 40 weight percent of an organic binder, 
at most about 40 weight percent of an organic char-forming component, and 
at most about 50 weight percent filler. The organic binder may be formed 
from a binder precursor which is either thermally or radiation curable, or 
mixture of thermally and radiation curable binder precursors. Examples of 
typical and preferred intumescent fire retardant composites are disclosed 
in U.S. Pat. No. 4,273,879, which is expressly incorporated by reference 
herein. This composition is a flexible rubbery material in its unexpanded 
state, but once subjected to temperatures on the order of 110.degree. C. 
and higher, intumesces up to 10 times it original volume and becomes a 
rigid char which is capable of sealing penetrations in which it is 
contained against the passage of smoke, vapors, and water. Other 
intumescent fire retardant materials may be used, such as those known 
under the trade designations " Palusol" (BASF) and "Expantrol" (3M). 
The inorganic fiber layer preferably comprises up to 98 percent by weight 
of inorganic fibers, and from about 2 to about 20 weight percent organic 
and/or inorganic binder. Useful inorganic fibrous materials include 
alumina-silicate fibers commercially available under the trade 
designations "Cerafiber" from Manville Corporation, "Kaowool" from Thermal 
Ceramics, and "Fiberfrax" from Carborundum Company, soft glass fibers 
commercially available under the trade designation "E-glass" from Manville 
Corporation, mineral wool, and refractory filaments such as 
zirconia-silica fibers and crystalline alumina whiskers. Suitable organic 
binders include rubber latices such as natural rubber, styrenebutadiene, 
butadiene-acrylonitrile, acrylates, an methacrylates. Suitable inorganic 
binders include bentonite and colloidal silica. Small amounts of 
surfactants, foaming agents, and flocculating agents may also be used if 
necessary. 
A particularly preferred inorganic fiber layer useful in flexible 
composites of the invention is a mixture of 50 weight percent mineral wool 
and 50 weight percent alumina-silicate fibers, bound together at points of 
mutual contact by an acrylic latex binder. An example of a method of 
making such an inorganic fiber layer is presented as Example 1. 
FIGS. 2 and 3 illustrate cross-sectional views of the flexible composites 
of the invention useful in systems of the invention for both dynamic and 
static joints. FIG. 2 shows a flexible composite 21 which includes a first 
layer 28 of inorganic fibers and binder, a second layer 26 of metal foil 
adhered to the first layer by a suitable adhesive, and a third layer 29 of 
a flexible intumescent fire retardant composite. Third layer 29 is 
partially intermingled between individual fibers of inorganic fiber layer 
28 during a coating process (described below) and requires no adhesive to 
bond to the first layer. 
The adhesive used to bond the metal foil layer 26 to the inorganic fiber 
layer 28 may be a pressure-sensitive adhesive or a thermoplastic material. 
For ease of processing, the metal foil and adhesive are preferably in the 
form of an aluminum foil/acrylic pressure-sensitive adhesive tape, such as 
that known under the trade designation "T-49" from 3M 
Preferred pressure-sensitive adhesives, because of their extended shelf 
life and resistance to detackifying under atmospheric conditions, are the 
acrylic-based copolymer adhesives, such as those disclosed in U.S. Pat. 
No. Re 24,906. 
It may be preferable to use thermoplastic or thermosetting polymeric 
adhesives, for example, in environments where an acrylic-based adhesive 
might prematurely crack. Thermoplastic polymers useful and preferred as 
adhesives include polyethylene and polypropylene. Thermosetting polymeric 
adhesives which are useful and preferred include the reaction product of a 
diisocyanate (such as toluene diisocyanate {TDI} and the like) and a 
polyester. One example of this latter adhesive found useful in the present 
invention is available from Morton Chemical Company, Chicago, Ill., under 
the trade designation "Adcote". 
Embodiment 30 of FIG. 3 is similar in all respects to embodiment 21 of FIG. 
2, except that the first or middle layer 32 includes unexpanded 
vermiculite. Unexpanded vermiculite will expand to up to 10 times its 
original volume upon exposure to a temperature of about 300.degree. C. As 
noted previously, unexpanded vermiculite comprises no more than about 65 
weight percent of the total weight of layer 32. 
FIG. 4 illustrates in cross-section a flexible composite embodiment 
suitable for use as a fire barrier for static joints and may be used in 
"short" versions of the systems of the invention, as illustrated in FIGS. 
10-14, and described further below. Illustrated is layer 28 of inorganic 
fibers and binder with a coating of metal foil 26 laminated thereto, as 
above described. 
In embodiments 20, 30, and 40, the metal foil is preferably either aluminum 
or one of the stainless steels, such as type 304, and the like. The foil 
thickness may range from about 10 micrometers to about 200 micrometers, 
preferably from about 30 to about 70 micrometers. Thickness of metal foil 
may increased to provide a stronger flexible composite and for lessening 
the chance of breaking the inorganic fiber/foil laminate in the process of 
coating the intumescent fire retardant coating thereon. However, metal 
foils having thickness above about 200 micrometers significantly reduces 
the flexibility of the flexible composites, thus making the task of 
installation more difficult. Thicker foils are also not preferred from an 
economic standpoint. 
FIGS. 5 and 6 illustrate, again in cross-sectional views, flexible 
composites 50 and 60 in accordance with the present invention. Flexible 
composites 50 and 60 are suitable for use fire barriers for static and 
dynamic joints, but only the "short" embodiments of the latter (see 
discussion of FIGS. 10-14, below). Flexible composite 50 includes layer 28 
of inorganic fibers and binder, as in the previous embodiments, and two 
layers 29 of flexible intumescent fire retardant composite. Between the 
two layers 29 is a layer 34 of inorganic fabric, which lends strength to 
the flexible composite. Flexible composite 60, illustrated in 
cross-section if FIG. 6, includes a layer 28 of inorganic fiber and 
binder, as in all embodiments, sandwiched between two layers 34 of 
inorganic fabric. Composite 60 is completed by having two layers 29 of 
flexible intumescent fire retardant composite material as the external 
layers. As with flexible composite 50, the inorganic fabric layers 34 
increase the strength of the flexible composite so that the flexible 
composites withstand the hose stream test of ASTM E-119. 
The inorganic fabric in embodiments 50 and 60 preferably comprises glass 
fiber. 
FIGS. 7-9 illustrate "long" systems of the invention. System embodiment 70 
of FIG. 7 is one particularly preferred system of the invention. Either of 
the flexible composite embodiments 21 or 30 of FIGS. 2 and 3 may be used 
with this system to pass the time-temperature test utilized in ASTM E-119 
and E-814 tests, or their equivalent (test described in Example 6. FIG. 7 
shows essentially the same features as FIG. 1 with the addition of the 
flexible composite, denoted as having two portions 72 and 74. First 
portion 72 extends from mullion attachment pin 17 horizontally and then 
vertically past attachment pin 18, between the insulation 12 and safing 
14. Second portion 74 of the flexible composite includes the "S" shaped 
portion which is accumulated over the upper surface of safing 14, being 
attached to floor 20 by attachment pin 19. It will of course be understood 
by those of skill in the art that a plurality of attachment pins 17, 18, 
and 19 may be required, and that configurations other than "S-shaped" 
accumulations of flexible composite may be employed. 
Installation of the system shown in FIG. 7 may be either as a retrofit, 
wherein the thermal insulation 12 and safing 14 have been previously 
installed, for example, in an older building. Alternatively, the 
insulation, safing, and fire barrier may be installed as new construction. 
In either case, installation is simple and cost effective. The flexible 
composite 72 is first attached to the mullion 13 via pin 17. If the safing 
is already present, one must remove at least a portion of the safing to 
"thread" flexible composite 72 up to the next floor of the building. 
Thereafter safing 14 is inserted, and flexible composite portion 74 is 
accumulated over the safing, care being taken that the intumescent fire 
retardant side faces the interior of the building. It should be apparent 
to those skilled in the art that the terms "first" and "second" portions 
of the flexible composite do not mean that the flexible composite is 
necessarily in two separate pieces. As this embodiment illustrates, 
portions 72 and 74 are actually portions of a single flexible composite 
sheet. 
Intumescent caulk 75 is placed where shown in FIG. 7 to provide additional 
fume and smoke barriers. Preferably, a flexible intumescent fire retardant 
caulk is used having composition similar to the intumescent fire retardant 
composite described previously. Caulks known under the trade designations 
"CP 25WB" "CP 25N/S" "CP 25S/L" and "Firedam" available from 3M, are 
particularly well suited for this purpose. 
After caulk is in place the unattached end of flexible composite 74 is 
attached to the floor 20 via pin(s) 19. 
The system shown in FIG. 8 as embodiment 80 of the invention is an 
alternative to the embodiment of FIG. 7. In embodiment 80, safing 14 
extends from the butt end of the floor to the exterior glass, with thermal 
insulation 12 positioned above and below safing 14. In this system, all 
thermal insulation 12 can be glass fiber as long as safing 14 is mineral 
wool or similar high temperature resistant material. A first portion of 
flexible composite 72 of either FIGS. 2 or 3 is installed substantially 
parallel to the exterior glass of the building, intumescent side facing 
toward the exterior glass. A second portion 74 is attached to the first 
portion with caulk, as previously described, and accumulated over the 
upper surface of safing 14 and attached as illustrated to floor 20. In 
this embodiment, safing 14 is thus partially supported by Z-clip(s) 77 and 
by the lower thermal insulation panel 12. 
As a fire develops in the vicinity of safing 14, underneath floor slab 20, 
if thermal insulation 12 is glass fiber it will eventually disintegrate as 
heat builds. However, the flexible intumescent layer of the first portion 
of flexible composite 72 will intumesce and fill the gap between the 
exterior glass and safing, thus ensuring that no fire, smoke, or fumes 
enter the space above floor 20. This is true even if the wall and floor 
deform since slack exists in flexible composite portion 74. 
FIG. 9 shows another embodiment wherein the "long" flexible composite is 
used, again with either flexible composite embodiment of FIGS. 2 and 3. As 
with the embodiment shown in FIG. 7, thermal insulation 12 and safing 14 
may in this case be either glass fiber or high temperature resistant 
mineral wool or the like. Flexible composite portion 72, beginning at 
attachment pin 16, is positioned substantially adjacent and parallel to 
thermal insulation 12, with metal foil facing the interior of the 
building. Portion 72 is installed so that it hangs down vertically until 
it reaches a point near the safing, where it is formed a "U" shape, and 
attached via pin 19 to floor 20. Note that this construction allows the 
intumescent material to face downward, toward the fire in the vicinity of 
the safing. Additionally fire barrier component 72A can be positioned 
against thermal insulation 12 and attached with attachment pin 18. A 
second portion of flexible composite 74 is accumulated over the upper 
surface of safing 14, as in FIGS. 7 and 8. For added support for safing 
14, a Z-clip is preferably included in the construction as illustrated. 
The five "short" system embodiments of the invention shown in FIGS. 10-14 
may be used with either of the flexible composite embodiments of FIGS. 2 
and 3, and only if the thermal insulation and safing are all high 
temperature materials, such as mineral wool, alumina-silicate, or 
refractory, as glass fiber insulation will not withstand fire 
temperatures. Numerical indications in FIGS. 10-14 are the same as for 
FIGS. 7-9. The systems shown in FIGS. 10 and 11 are especially suited for 
retrofit application, whereas the systems of FIGS. 12-14 require that the 
safing 14 be partially removed, or installed prior to installation of the 
safing. In each embodiment, the intumescent side of the flexible 
composites of FIGS. 2 and 3 faces the fire or hot side of the joint. 
A method of making the three layer version of the flexible composite 
materials of the invention is also presented as another aspect of the 
invention. The method includes the steps of 
i) providing a laminate comprising inorganic fibers and a binder formed 
into a mat, the first layer having on one major surface thereof a second 
layer consisting essentially of metal foil adhered to the first layer by 
an adhesive; 
ii) coating an intumescent precursor solution comprising solvent and an 
intumescent fire retardant material onto the second major surface of the 
first layer to produce a wet coated composite material; and 
iii) exposing the wet coated composite material to conditions sufficient to 
cure the intumescent fire retardant material, thereby forming a flexible 
third layer comprising a the intumescent fire retardant material. 
Preferably the solvent is water or an organic solvent, the organic solvent 
selected from the group consisting of lower alkyl ketones (e.g. methyl 
ethyl ketone and the like), aromatic hydrocarbons (such as benzene, 
xylene, and the like), and other hydrocarbon solvents. 
The method of making the laminate of step (i) is not within the scope of 
this invention, although an example is presented below which teaches how 
to make one preferred inorganic fiber/metal foil laminate useful in the 
flexible composites of the invention. Briefly, the inorganic fiber mat of 
the laminate is made using conventional paper making techniques, and an 
adhesive used to adhere the metal layer to the inorganic fiber layer. The 
adhesive may either be a pressure-sensitive adhesive or a thermoplastic. 
The latter may be preferred to prolong the life of the flexible composites 
of the invention, as many pressure-sensitive adhesives tend to become 
brittle with the passage of time. 
After the inorganic fiber/metal foil laminate is produced, an intumescent 
precursor solution is coated onto the laminate on the side of the laminate 
not having foil. Coating of the intumescent precursor solution may be 
performed by any of a number of ways within the scope of the invention. 
Preferred methods use horizontal or vertical (tower) coating machines. 
The preferred method of curing the intumescent fire retardant composite is 
by the application of heat, although the use of radiation curable organic 
binders alone or in combination with thermally curable binders may be 
preferred in certain circumstances. 
When thermally curable binders are used to form the intumescent fire 
retardant composite, conventional roll, flow bar, and knife coating 
machines may be utilized to apply the intumescent precursor solution 
(comprising the intumescent fire retardant material and a solvent) to an 
exposed major surface of the inorganic fiber layer. 
The number of drying ovens, temperature of the ovens, number of coats of 
precursor solution applied, and thickness of the individual coats may 
vary. 
The method of the invention may be further understood with reference to the 
following examples, in which all parts and percentages are by weight 
unless otherwise stated. 
EXAMPLES 
Example 1: Production of an Inorganic Layer Comprising Mineral Wool and 
Alumina-silicate Fibers/Aluminum Foil Laminate 
The component ingredients and amounts used to make the preferred inorganic 
fiber layer/metal foil laminate are presented in Table 1. The mineral wool 
was first slushed in a pulper, charging about one half of the total weight 
of mineral wool (300 kg) and 12.7 kiloliters (kl) of water. This charge 
was slushed for 15 seconds, and subsequently pumped to a cyclone cleaner 
(known under the trade designation "Krebs"). The flow through the cyclone 
cleaner was adjusted to about 1 kl/min at 25 psig pressure. The two 
effluents ("accept" effluent and "reject" effluent) from the cyclone 
cleaner were inspected for shot and percent solids after the flow had 
stabilized through the accept effluent conduit using a 2.54 cm diameter 
orifice. The reject rate was about 5-10% of the weight of original mineral 
wool charge. The accept effluent was subsequently fed into a precipitation 
chest. 
The above steps were repeated with the remaining mineral wool, with a 
proportionate amount of water. 
After two batches of mineral wool reached the precipitation chest and 
tested for percent solids, all of the alumina-silicate fibers were fed to 
the pulper with 18.2 kl of water. The alumina-silicate fibers were slushed 
for 60 seconds in the pulper, and then pumped into the precipitation chest 
to form a slurry with the mineral wool. 
TABLE 1 
______________________________________ 
Ingredient Amount (kg or ml) 
______________________________________ 
water 47.3 
mineral wool 604 
(Bethleham) 
alumina-silicate fibers 
613 
("Cerafiber", Manville 
Corporation) 
sodium aluminate 20.4 
("2372", Nalco Chemical) 
46% solids acrylic latex 
409 
("Rhoplex HA-8", 
Rohm & Haas) 
defoaming agent 0.91 ml 
("Foammaster 
DF-160-LP, 
) 
liquid alum 50.9 ml 
______________________________________ 
The slurry of mineral wool fibers and alumina-silicate fibers was 
precipitated by first adding sodium aluminate with mixing until the pH of 
the slurry reached 8.0 or above. The acrylic latex, defoamer, and liquid 
alum were then added in order, with the pH of the slurry after addition of 
the liquid alum checked to be sure it was 6.5 or below. The slurry was 
then pumped to a machine chest. 
The inorganic fiber layer was produced by a conventional wet lay paper 
technique, dried, and wound on a reel without a liner. After the basis 
weight of a wet 10.2 cm.times.15.2 cm sample of the web reached a target 
weight of about 20-25 gm, a flexible composite of the invention was made 
by forcing aluminum foil tape (known under the trade designation "T-49" 
having aluminum thickness of about 50 micrometers and a polyester/TDI 
adhesive into the nip at the reel, with the adhesive of the tape facing 
the top side of the inorganic fiber layer. 
Example 2: Production of an Inorganic Layer Comprising 100% 
Alumina-silicate Fibers/Aluminum Foil Laminate 
A second laminate was formed in exactly the same manner as in Example 1, 
the only difference being the deletion of mineral wool. 
Example 3: Production of Flexible Composite Using Example 1 Inorganic Layer 
and Water-based Intumescent Precursor Solution 
A length of 45.7 meters of 1.22 meter wide laminate of Example 1 was coated 
with an intumescent precursor solution comprising the ingredients listed 
in Table 2. The intumescent precursor solution was about 76% solids, and 
had a viscosity of about 24,000 centipoise, measured using a Brookfield 
viscometer, Model "RV" #4 spindel, 6 rpm, at about 20.degree. C. This 
intumescent precursor solution was coatable and sprayable. The intumescent 
precursor solution was applied using a horizontal roll coater having three 
heating zones, with the first, second, and third, heating zones having 
temperatures of 120.degree. C., 143.degree. C., and 154.degree. C., 
respectively. The intumescent precursor solution was applied having a dry 
coating weight of 2260 gm/m.sup.2 (gsm). This coating was blistered. 
TABLE 2 
______________________________________ 
Ingredients Amount (parts) 
______________________________________ 
polychloroprene latex 
8619 
antifoam agent 49 
("Foamaster") 
water 49 
surfactant 203 
("Triton X-100") 
surfactant 203 
("Tamol 850") 
agerite 101 
zinc oxide 254 
iron oxide (FeO) 254 
zinc borate/sodium silicate 
4325 
("Expantrol 4B") 
aluminum hydroxide 1524 
glass fibers 509 
______________________________________ 
Example 4: Production of Flexible Composite Using Example 2 Inorganic Layer 
and Water-based Intumescent Precursor Solution 
A length of 36.6 meters of 1.22 meter wide laminate of Example 2 was coated 
using intumescent precursor solution made in accordance with Example 3. 
The intumescent precursor solution was again applied with a horizontal 
roll coater, with the same heating zone temperatures as used in Example 3. 
This coating was also blistered. 
Example 5: Production of Flexible Composite Using Example 2 Inorganic Layer 
and Organic Solvent-based Intumescent Precursor Solution 
A length of 265 meters of 1.22 meter wide laminate of Example 2 was coated 
with an intumescent precursor solution comprising the ingredients listed 
in Table 3. 
TABLE 3 
______________________________________ 
Ingredient Amount (parts) 
______________________________________ 
xylene 22.5 
methyl ethyl ketone 
22.5 
calcium carbonate 
16.6 
polychloroprene latex 
15.7 
sodium silicate 9.3 
zinc borate 1.8 
chlorinated olefins 
4.5 
2-ethylhexyldiphenyl 
2.8 
phosphate 
water 2.6 
______________________________________ 
The intumescent precursor solution had a viscosity of 40,000 centipoise, 
measured using a Brookfield viscometer model "RV" #4 spindel, 6 rpm, at 
about 20.degree. C. A horizontal roll coater was used, as in Examples 3 
and 4. Using first, second, and third heating zone temperatures of 
93.degree. C., 99.degree. C. and 107.degree. C., respectively, and machine 
speed of 3 meters/min, the coating did not cure. The heating zone 
temperatures were then raised to 121.degree. C., 143.degree. C., and 
154.degree. C., which produced cured coatings having coating weight (dry) 
of 1033 gsm. Blistered coatings were produced. 
Example 6: Production of Flexible Composite Using Example 2 Inorganic Layer 
(Containing Vermiculite), and Organic Solvent-based Intumescent Precursor 
Solution 
As earlier disclosed, the inorganic fibrous layer used in the flexible 
composites of the invention may include vermiculite. This Example used a 
commercial mat available under the trade designation "Interam 2100", 
commercially available from 3M, which had aluminum foil adhesive tape 
(known under the trade designation "T-49") laminated thereto. This 
inorganic fibrous layer was essentially the same as that of Example 2, 
except the layer included about 50 weight percent cationically exchanged 
vermiculite, as disclosed in U.S. Pat. No. 4,305,992, which is 
incorporated by reference. The inorganic fibrous layer of this Example was 
coated with an intumescent precursor solution made in accordance with 
Example 5. 
Comparative Example A 
For comparison in the fire rating and hose stream tests (described below), 
a commercially available aluminum foil/mineral wool laminate (known under 
the trade designation "Thermafiber Life Safety System", from United States 
Gypsum Company) was employed as Comparative Example A. 
In making the flexible composites of the invention in the above Examples 
1-6, a horizontal roll coater was employed. A tower knife coater may also 
be employed. It has been found that in the case of a tower knife coater 
(wherein the inorganic fiber/metal foil laminate is threaded and pulled 
vertically through two serially arranged vertical heating zones, with one 
intumescent precursor solution coated onto the laminate in each zone), the 
first vertical heating zone temperature should generally be about 
90.degree. C. while the second vertical heating zone temperature is 
preferably about 110.degree. C. These conditions are appropriate for 
coating an intumescent caulk known under the trade designation "CP 25N/S" 
(3M) diluted to 55% solids with methyl ethyl ketone, at wet thickness of 
0.2 cm, pulling the laminate through the tower coater at a rate of about 
55 meters/hr. Spray coating has also been evaluated for the water-based 
intumescent precursor solutions with some success. 
In some of the flexible composites made by the above procedures (both in 
horizontal and tower coaters), blistering of the flexible intumescent 
coatings during heating occurred. This was believed due to the entrapment 
of solvent in bubbles as the composite passed through the heating zones of 
the dryers. Through suitable adjustment of speed through the zones, and/or 
lowering of the coating thickness, blistering was overcome. It was also 
noted that the location where the precursor slurry was pumped into the 
coating pan was where blistering seemed to occur most. The occurrence of 
blisters was substantially eliminated by judicious placement of the feed 
to the coating pan. 
Another problem was splice failures. High tension was needed to pull the 
coated laminates through the ovens or heating zones. Splices made with 
high temperature adhesive on film backing, with long (60-90 cm) 
longitudinal strips on each side of the splice worked well; however, 
normal, short splices would fail midway through the heating zones, 
especially in vertical tower coaters. Even with a splice failure, however, 
splices could be remade in the oven without a significant loss of product. 
Starting and stopping the horizontal and tower coating processes was also 
performed quickly. The most effective splice tape found for this coating 
process was a 20.3 cm wide pressure-sensitive tape having a high 
temperature polyester/TDI thermoset adhesive. 
Test Method 
A test procedure was developed by the assignee of this invention so that 
systems comprising thermal insulation and the flexible composites of the 
invention could be evaluated in dynamic joints. The test was developed to 
simulate a "real world" fire in which the vertical wall and floor deform. 
Test "specimens" were constructed as shown in FIG. 7. Floor slab 20 was 
concrete and had thickness of 11.43 cm, while in place of spandrel glass 
10, a 10.2 cm thick, vertical concrete slab was used. Two pieces of 5.1 
cm.times.2.54 cm aluminum mullion were installed vertically, separated by 
61 cm, with a 2.54 cm gap between the vertical concrete slab and mineral 
wool insulation, also of 10.2 cm thickness. The safing was 10.2 cm thick 
mineral wool. The flexible composite to be tested was installed as shown 
in FIG. 7, and the structure heated from below using time-temperature 
curves of ASTM tests E-119 and E-814. A thermocouple was placed near the 
"cold" side of the safing (near the thermal insulation) and the 
temperature recorded at 20 minute intervals. The results for Examples 2, 
5, 6, and Comparative Example A are presented in Table 1. 
Hose stream tests in accordance with ASTM E-119 and E-814 were also 
performed on the inventive Examples and Comparative Example A. The water 
spray was 6.1 meters from center, using 45 seconds sweep time and at 0.2 
megaPascals water pressure. The results for the hose stream test (denoted 
"HS") are presented in Table 4 as "P" for "pass" and "F" for "fail". 
TABLE 4 
______________________________________ 
Results of Fire Test and Hose Stream Test 
Temperature (.degree.C.) at Time (min.) 
H 
Example 
20 40 60 80 120 140 160 180 S 
______________________________________ 
2 27 63 88 91 93 96 107 121 P 
5 26 49 66 71 82 96 99 107 P 
6 29 46 63 71 82 116 124 135 P 
A 38 68 96 88 182 204 210 227 F 
______________________________________ 
Whether a fire barrier passes the fire test is determined by noting the 
cold side temperature after 1 hour (ASTM E-814) and 2 hours (ASTM E-119). 
The cold side temperature should be below 163.degree. C.+ambient 
temperature to pass ASTM E-814, and below 121.degree. C.+ambient 
temperature to pass ASTM E-119. As may be seen by the data in Table 4, 
even the aluminum foil/inorganic fibrous laminate of Example 2 would pass 
the fire rating test and hose stream test; however, since intumescent 
layer is not present in Example 2, there would still be a chimney for 
smoke and possibly toxic fumes. Note that the Comparative Example did not 
pass either the equivalent of the ASTM E-119 time-temperature test or the 
hose stream test. 
Various modifications and alterations of this invention will become 
apparent to those skilled in the art without departing from the scope and 
spirit of this invention, and it should be understood that this invention 
is not to be unduly limited to the illustrative embodiments set forth 
herein.