Note: Descriptions are shown in the official language in which they were submitted.
CA 02554754 2006-08-23
1714CAN
METALLIZED POLYMERIC
FILM REFLECTIVE INSULATION MATERIAL
FIELD OF THE INVENTION
This invention relates to metallized polymeric reflective insulation material,
particularly, bubble pack insulation material for use in an environment that
requires a Class A
standard insulation material, particularly, as packaging, and in vehicles,
and, more
particularly, in residential, commercial and industrial buildings and
establishments
comprising a framed structure, walls, crawl spaces and the like, and wrapping
for water
heaters, pipes and the like.
BACKGROUND OF THE INVENTION
Insulation materials are known which comprise a clean, non-toxic, heat barrier
made
of aluminum foil bonded to polymeric materials.
Examples of such insulation materials, includes aluminum foil backing with
foam
materials selected from closed cell foams, polyethylene foams, polypropylene
foams and
expanded polystyrene foams (EPS).
Alternative insulation materials in commercial use are made from aluminum foil
bonded to a single or double layer of polyethylene-formed bubbles spaced one
bubble from
another bubble in the so-called "bubble-pack" arrangement. Such non-foil
bubble-packs are
used extensively as packaging material, whereas the metal foil bubble-pack is
used as thermal
insulation in wood frame structures, walls, attics, crawl spaces, basements
and the like and as
wrapping for hot water heaters, hot and cold water pipes, air ducts and the
like. The reflective
surface of the metal, particularly, aluminum foil enhances the thermal
insulation of the air-
containing bubble pack.
Organic polymers, such as polyethylene, are generally considered to be high-
heat-
release materials. They can easily initiate or propagate fires because, on
exposure to heat,
they undergo thermal degradation to volatile combustible products. If the
concentration of the
degradation products in the air is within flammability limits, they can ignite
either
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spontaneously, if their temperature is large enough, or by the effect of an
ignition source such
as a spark or flame. The ignition of polyethylene can be delayed and/or the
rate of its
combustion decreased by means of fire retardant materials.
The ultimate aim of fire retardants is to reduce the heat transferred to the
polymer
below its limit for self-sustained combustion or below the critical level for
flame stability.
This can be achieved by decreasing the rate of chemical and/or physical
processes taking
place in one or more of the steps of the burning process. One or a combination
of the
following can achieve fire extinguishing:
1. creation of a heat sink by using a compound that decomposes in a highly
endothermic reaction giving non-combustible volatile products, which perform a
blanketing
action in the flame, e.g., aluminum or magnesium hydroxide;
2. enhancements of loss of heat and material from the surface of the burning
polymer
by melt dripping, e.g., mixture of halogenated compounds with free radical
initiators;
3. flame poisoning by evolution of chemical species that scavenge H and OH
radicals
which are the most active in propagating thermo-oxidation in the flame, e.g.,
hydrogen
halides, metal halides, phosphorus-containing moieties;
4. limitation of heat and mass transfer across the phase boundary, between
thermal
oxidation and thermal degradation by creation of an insulating charred layer
on the surface of
the burning polymer, e.g., intumescent chart; or
5. modification of the rate of thermal volatilization of the polymer to
decrease the
flammability of the volatile products; which approach strongly depends on the
chemical
nature of the polymer.
Fire retardant materials are generally introduced to the polyethylene as
merely
additives or as chemicals that will permanently modify its molecular
structure. The additive
approach is more commonly used because it is more flexible and of general
application.
Generally, low density polyethylene films of 1-12 mil, optionally, with
various
amounts of linear low density polyethylene in admixture when additional
strength is required,
are used for the above applications. The insulating properties of the bubble
pack primarily
arise from the air in the voids. Typically, bubble diameters of 1.25 cm, 0.60
cm and 0.45 cm
are present.
Regardless of the application method of fire retardant material(s), a
satisfactory
insulative assembly must have a fire rating of Class A with a flame spread
index lower than
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16, and a smoke development number smaller than 23. Further, the bonding of
the organic
polymer films and their aging characteristics must meet the aforesaid
acceptable standards.
Yet further, the fabrication method(s) of a new fire retardant system or
assembly should be
similar to the existing technology with reasonable and cost effective
modifications to the
existing fabrication system/technology. Still yet further, other physical
properties of an
improved fire standard system must at least meet, for example, the standard
mechanical
properties for duct materials as seen by existing competitive products.
Fire retardant polyethylene films, wires and cables containing a fire
retardant material
in admixture with the polyethylene per se are known which generally satisfy
cost criteria and
certain fire retardant technical standards to be commercially acceptable.
Conventional fire retardant additives are usually compounds of small molecular
weights containing phosphorus, antimony, or halogens. The most effective
commercially
available fire retardant systems are based on halogen-containing compounds.
However, due
to concerns over the environmental effects of such halogenated compounds,
there is an
international demand to control the use of such halogenated additives.
Some of the most common halogenated agents are methyl bromide, methyl iodide,
bromochlorodifluoromethane, dibromotetrafluoroethane, dibromodifluoromethane
and
carbon tetrachloride. These halogenated fire retarding materials are usually
available
commercially in the form of gases or liquids. Unlike chlorine and bromine,
fluorine reduces
the toxicity of the material and imparts stability to the compound. However,
chlorine and
bromine have a higher degree of fire extinguishing effectiveness and,
accordingly, a
combination of fluorine and either chlorine or bromine is usually chosen to
obtain an
effective fire-retarding compounds.
Other commercially available fire retardant materials that do not include
halogens
include boric acid and borate based compounds, monoammonium phosphonate, and
urea-
potassium bicarbonate.
Intumescent compounds which limit the heat and mass transfer by creating an
insulating charred layer on the surface of the burning polymer are also
considered fire
retardant materials. A typical intumescent additive is a mixture of ammonium
polyphosphate
and pentaerythritol.
Fire retardant additives are often used with organic polymer/resins.
Typically, a
brominated or chlorinated organic compound is added to the polymer in
admixture with a
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metal oxide such as antimony oxide. Halogenated compounds are also sometimes
introduced
into the polymer chain by co-polymerization. Low levels i.e. less than 1% W/W
are
recommended to make adverse effects of halogen-based systems negligible.
Another
common fire retardant additive is diglycidyl ether of bisphenol-A with
MoO3. Other
additives to improve the fire retarding properties of polyethylene include,
for example, beta-
cyclodextrin, magnesium hydroxide and alumina trihydrate, tin oxide, zinc
hydroxystannate,
and chlorosulphonated polyethylene.
United States Patent No. 6,322,873, issued November 27, 2001 to Orologio,
Furio,
describes a thermally insulating bubble pack for use in framed structures,
walls, crawl spaces
and the like; or wrapping for cold water heaters, pipes and the like wherein
the bubbles
contain a fire retardant material. The improved bubble pack comprises a first
film having a
plurality of portions wherein each of the portions defines a cavity; a second
film in sealed
engagement with the first film to provide a plurality of closed cavities; the
improvement
comprising wherein the cavities contain a fluid or solid material. The flame
retardant-
containing bubble pack provides improved fire ratings, flame spread indices
and smoke
development numbers. The preferred embodiments include a layer of metal or
metallized
film adjacent at least one of the films. However, the efficacious manufacture
of the fire
retardant-filled bubbles still represents a challenge.
Aforesaid bubble-packs not containing fire retardant materials and having a
nietallized film layer are known and used for external insulation around large
self-standing
structures, such as tanks, silos and the like, particularly in the oil and
chemical industries,
which insulation assembly does not have to meet the rigorous fire retardant
standards for
insulation in framed structures of residential, commercial and industrial
buildings, crawl
spaces and the like or wrappings for cold water heaters, pipes and the like,
therein.
Metallized films and their methods of production are well-known in the art.
One
technique is to evaporate an extremely thin layer of nearly pure aluminum onto
a surface of
the non-porous plastics material under vacuum by a so-called 'vacuum
metallizer'. Preferred
metallized films of use in the practise of the invention are metallized
aluminum coated
polymer films, preferably, for example, 48 gauge PET (polyethylene
terephthalate).
There is, however, always the need for insulation assembly, having improved
fire
retardant standards, particularly when safety building codes are being
continually improved.
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Standards for many products are generally being raised to enhance safety. This
is true
for reflective insulation materials for use in buildings, which must meet
minimum surface
burning characteristics to satisfy codes, such as CAN/ULC S201, UL723, ANSI
No. 2.5,
NFPA No. 255 and 286, UBC 42-1, ASTM E84-05 and others. These tests cover two
main
parameters, mainly, Flame Spread and Smoke Developed Values.
Such reflective insulation materials are classified as meeting the ratings as
follows:-
Interior Wall and Ceiling Finish Flame Speed Value Smoke Developed Value
Class A 0-25 0-450
Class B 26-75 0-450
Class C 76-200 0-450
The classification determines the environmental allowability of the reflective
niaterials insulation.
The standard ASTM E84 and its variations tests, todate, have included,
typically, the
use of a hexagonal 50mm steel wire mesh with 6mm diameter steel rods spaced at
610mm
intervals to support the insulation materials.
Without being bound by theory, the skilled persons in the art have discovered
that the
aforesaid use of the wire mesh support in the tests has enabled some
reflective insulation
materials to satisfy the Class A standard, whereas removal of the support in
the test has
caused these materials not to meet the standard.
Surprisingly, I have discovered that substitution of metallic foil,
particularly,
aluminum foil, with a metallized, particularly, aluminum, coating on an
organic polymer
layer, e.g. polyethylene and more particularly PET (polyethylene teraphthate),
favourably
enhances the surface burning characteristics of the reflective insulation in
the aforesaid
ASTM E84 test in the absence of the wire mesh support. The reason for this
discovery is not,
as yet, understood.
Further, I have discovered that the presence of a fire retardant compound in
or on one
or more of the polymer layers of a reflective insulation assembly further
favourably enhances
the surface burning characteristics of the insulation, and in preferred
embodiments
significantly enhances the safety of the assemblies as to satisfy the criteria
set in the most
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stringent "Full Room Bum Test for Evaluating Contribution of Wall and Ceiling
Finishes to
Room Fire Growth - NFPA 286.
Metallized polymeric films having an outer lacquer coating are known in the
foodstuff
packaging industry in order to provide physical protection to the ink printed
on the outer
metallic surface. Manual contact with the unprotected inked material surface
would cause
inconvenience to the person and possibly contamination of the foodstuffs, such
as
confectionary and potato chips when handed by the person. The lacquer-coated
outer metallic
surface overcomes this problem in the foodstuff art.
Surprisingly, I have found that the most preferred metallized polymeric film
reflective
insulation materials, particularly the fire-retardant containing assemblies,
according to the
invention provide improved safety towards fire and also acceptable reflectance
and anti-
corrosive properties.
SUMMARY OF THE INVENTION
It is an object of the present invention to provide metallized polymeric film
reflective
insulation material having Class A thermal insulation properties,
particularly, metallized
bubble pack insulation material for use in an environment that requires a
Class A standard
insulation material, particularly, as packaging, and in vehicles, and more
particularly in
residential, commercial and industrial buildings and establishments having
framed structures,
walls, crawl spaces and the like, and wrapping for water heaters, pipes and
the like having
iinproved fire retardant properties.
It is a further object to provide a method of thermally insulating an
aforesaid vehicle,
building or establishment with a Class A standard metallized polymeric
reflective insulation
material having improved fire-retardant properties.
In yet a further object, the invention provides an improved thermally-
insulated
vehicle, building or establishment having a Class A standard metallized
polymeric reflective
insulation material.
Accordingly, the invention in one aspect provides a method of thermally
insulating an
object that requires a Class A standard insulation material, said method
comprising suitably
locating a metallized polymeric reflective insulation material adjacent said
object, wherein
said polymeric material is selected from a closed cell foam, polyethylene
foam,
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polypropylene foam, expanded polystyrene foam, multi-film layers assembly and
a bubble-
pack assembly.
Without being limiting, the object is preferably selected from the group
consisting of
vehicles and residential, commercial and industrial building and
establishment.
The term 'vehicle' includes, for example, but not limited to, automobiles,
buses,
trucks, train engines and coaches, ships and boats.
The invention provides in a further aspect, a method of thermally insulating a
residential, commercial or industrial building with a metallized polymeric
material, said
method comprising locating said metallized polymeric material within a frame
structure,
crawl space and the like, or wrapping water heaters, pipes, and the like,
within said building,
wherein said polymeric material is selected from a closed cell foam,
polyethylene foam,
polypropylene foam, expanded polystyrene foam and a bubble-pack assembly.
The invention provides in a further aspect a method of thermally insulating a
residential, commercial or industrial building with a bubble-pack assembly,
said method
comprising locating said bubble pack within a framed structure, wall, crawl
space and the
like, or wrapping water heaters, pipes and the like within said building; and
wherein said
bubble-pack assembly comprises a first thermoplastic film having a plurality
of portions
wherein each of said portions defines a cavity; a second film in sealed
engagement with said
first film to provide a plurality of closed said cavities; and at least one
layer of metallized
thermoplastic film.
The terms "cavity" or "cavities" in this specification include voids, bubbles
or other
like closed spaces. The cavities may be formed of any desired suitable shapes.
For example,
semi-cylindrical, oblong or rectangular. However, a generally, hemi-spherical
shape is
preferred.
Most surprisingly, I have found that the use of at least one layer of
metallized
thermoplastic film provides enhanced fire retardant properties over those
having only a
corresponding layer(s) of aluminum foil, in the bubble-pack assembly.
In a further aspect, the invention provides a method as hereinabove defined
wherein
said bubble-pack assembly comprises
(i) a first bubble pack having a first thermoplastic film having a plurality
of portions
wherein each of said portions defines a cavity and a second thermoplastic film
in sealed
engagement with said first film to provide a plurality of closed said
cavities; and
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(ii) a second bubble-pack having a third thermoplastic film having a plurality
of portions
wherein each of said portions defines a cavity and a fourth thermoplastic film
in sealed
engagement with said third film to provide a plurality of closed said
cavities; provided that
when said at least one of said layers of metallized thermoplastic film is
interposed between
and bonded to said first bubble pack and said second bubble pack, said
assembly comprises at
least one further metallized thermoplastic film.
In a further aspect, the invention provides a method as hereinabove defined
wherein
said bubble-pack assembly comprises
(i) a first bubble pack having a first thermoplastic film having a plurality
of portions
wherein each of said portions defines a cavity and a second thermoplastic film
in sealed
engagement with said first film to provide a plurality of closed said
cavities; and
(ii) a second bubble-pack having a third thermoplastic film having a plurality
of portions
wherein each of said portions defines a cavity and a fourth thermoplastic film
in sealed
engagement with said third film to provide a plurality of closed said
cavities;
(iii) a metallized thermoplastic film interposed between and bonded to said
first bubble
pack and said second bubble pack; and wherein at least one of said first
second, third, fourth
or additional thermoplastic films contains an effective amount of a fire-
retardant material.
The assembly, as hereinabove defined, may have at least one outer layer of
metallized
thermoplastic film, or, surprisingly, one or more inner, only, layers:
The assembly may, thus, further comprise at least one or a plurality of
additional
thermoplastic films.
Further, I have found that the use of a fire-retardant material in any or all
of the
thermoplastic films of the assembly enhances the fire-retardant properties of
the assembly.
Accordingly, in a further aspect, the invention provides a bubble-pack
assembly
comprising
(i) a first thermoplastic film having a plurality of portions wherein each of
said portions
defines a cavity;
(ii) a second film in sealed engagement with said first film to provide a
plurality of closed
said cavities; and
(iii) at least one layer of a metallized thermoplastic film; and wherein at
least one of said
first or second films contains an effective amount of a fire-retardant.
In a further aspect, the invention provides a bubble-pack assembly comprising
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(i) a first bubble pack having a first thermoplastic film having a plurality
of portions
wherein each of said portions defines a cavity and a second thermoplastic film
in sealed
engagement with said first film to provide a plurality of closed said
cavities; and
(ii) a second bubble-pack having a third thermoplastic film having a plurality
of portions
wherein each of said portions defines a cavity and a fourth thermoplastic film
in sealed
engagement with said third film to provide a plurality of closed said
cavities.
Further, the metallized thermoplastic film may also contain a fire-retardant
material to
further enhance the assemblies' fire-retardant properties.
The thermoplastic films may be formed of any suitable polymer or copolymer
niaterial. The first and second film may be formed of the same or different
material. Most
preferably, the bubble pack has each of the films formed of a polyethylene.
The metallized thermoplastic film is preferably a polyester, and, more
preferably, a
polyethylene terephthate having a metal coating.
The fire retardant material may be a compound or composition comprising one or
more compounds having acceptable fire retardant properties.
The amount of fire retardant material is such as to provide an efficacious
amount in
relation to the amount of plastic and other components present in the bubble
pack. Thus, the
amount of fire retardant material required will depend on the application of
the assembly, the
type and effectiveness of the fire retardant material used, the final
properties required e.g.
flame spread index, slow burning or self-extinguishing, and the bubble size.
The fire retardant
is generally present in an amount selected from 0.1-70% w/w, more preferably,
10-60% w/w,
preferably 15-20% w/w in relation to the thermoplastic film.
Examples of suitable fire retardants of use in the practice of the invention,
include
those classes and compounds as hereinbefore described. Preferably, the fire
retardant
compound is selected from alumina trihydrate (ATH, hydrated aluminum oxide,
A1203.3H20), oxides of antimony, decabromodiphenyl oxide and mixtures of these
compounds, optionally with a dimethyl siloxane fluid (DC200).
The bubble-pack further comprises one or more organic polymer films metallized
with a suitable metal, for example, aluminum to enhance reflection of infra-
red radiation.
Thus, while the most preferred plastics material for the bubble and laminated
layers is
polyethylene, particularly a low-density polyethylene, optionally, in
admixture with a linear
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low density polyethylene, of use as aforesaid first and second films, the
metallized organic
polymer is a polyester, preferably polyethylene teraphthalate.
The number, size and layout of the bubbles in the pack according to the
invention may
be readily selected, determined and manufactured by the skilled artisan.
Typically, in a single
pack, the bubbles are arrayed in a coplanar off-set arrangement. Each of the
hemi-spherical
bubbles may be of any suitable diameter and height protruding out of the plane
of the bonded
films. Typically, the bubble has a diameter selected from 0.5 cm -5 cm,
preferably 0.8-1.5
cm; and a height selected from 0.2 cm -1 cm, preferably 0.4-0.6 cm. A
preferred bubble pack
has an array of about 400 bubbles per 900 cm2.
In a further aspect, the invention provides a vehicle or a residential,
commercial or
industrial building or establishment insulated with a multi-film layer or
bubble-pack
assembly, according to the invention
Surprisingly, I have also discovered that a clear polymeric lacquer coating
applied to
the metallic layer having the higher reflectivity (bright) surface as the
outer layer provides a
protective layer to manual handling without significant loss of reflectance.
Thus, I also have
found that a suitable and effective thickness of the lacquer polymeric coating
can provide
satisfactory anti-corrosion protection to the metal surface and still allow of
sufficient
reflectance as to meet the emissivity standard as set by the industry. A
reflectance of greater
than 95% has been maintained for preferred embodiments of the clear lacquer-
coated
metallized polymeric reflective insulation materials, according to the
invention. A preferred
lacquer comprises an acrylic polymer or copolymer. More preferably, the
acrylic polymer is
polymethyl methacrylate, particularly having a molecular weight of 80,000 -
150,000.
Accordingly, in a further aspect the invention provides a metallized polymeric
reflective film insulation material, as hereinabove defined and having a
metallic coating outer
layer having a clear lacquer coating.
The clear lacquer coating may be applied to the highest reflectance surface,
i.e. the
bright side, of the metallic surface by techniques, such as by brushing,
spraying, deposition
and the like, as is well-known in the art. Preferred lacquers are clear, cross-
linked polymers
well-known in the art.
1 have also found that preferred embodiments of the aforesaid lacquer-coated,
metallized polymeric insulative materials according to the invention provide
satisfactorily
meet the industry's corrosivity standards.
CA 02554754 2006-08-23
BRIEF DESCRIPTION OF THE DRAWINGS
In order that the invention may be better understood, preferred embodiments
will now
be described by way of example only, with reference to the accompanying
drawings wherein
Fig. I represents diagrammatic, exploded section views of a metallized-double
bubble-white polyethylene, with fire retardant, assembly according to the
invention (Example
1);
Fig. 2 represents the assembly of Fig. I without fire retardant being present,
according
to the invention (Examples 2 and 3);
Fig. 3 represents a diagrammatic, exploded sectional view of a metallized-
single
bubble-white polyethylene without fire retardant assembly, according to the
invention
(Example 4);
Fig. 4 represents a diagrammatic, exploded sectional view of a metallized-
double
bubble-metallized assembly without fire retardant, according to the invention
(Example 5);
Fig. 5 represents a diagrammatic, exploded sectional view of a metallized-
double
bubble-metallized assembly with fire retardant, according to the invention
(Example 6);
Fig. 6 represents a diagrammatic, exploded view of an aluminum foil-single
bubble-
aluminum foil-scrim without fire retardant according to the prior art (Example
7);
Fig. 7 represents a diagrammatic, exploded view of an aluminum foil-single
bubble-
aluminum foil with fire retardant reflective insulation assembly, not
according to the
invention (Example 8);
Fig. 8 represents a diagrammatic, exploded view of an aluminum foil-single
bubble-
white poly with fire retardant not according to the invention (Example 9);
Fig. 9 represents an exploded view of a metallized-double bubble-metallized-
double
bubble-metallized assembly having fire retardant, according to the invention
(Example 10);
Fig. 10 represents an exploded view of a metallized double bubble-white
polythene
with fire retardant assembly, according to the invention (Example 11);
Fig. 11 represents an exploded view of a metallized-single bubble-metallized
without
fire retardant assembly, according to the invention (Example 12);
Fig. 12 represents an exploded view of an aluminum foil-single bubble
containing fire
retardant not according to the invention (Example 13);
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Fig. 13 represents an exploded view of an aluminum foil-double bubble-aluminum
foil, according to the prior art (Examples 14 and 15);
Figs. 14, 15 and 16 are diagrammatic, exploded sectional views of a bubble-
pack,
scrim laminated insulation blanket, according to the invention; and
Fig. 17 is a clear lacquer-coated metallized embodiment of Fig. 3.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
Fig. 14 is a bubble-pack-scrim laminated blanket assembly having polyethylene
layers
112, 114, 116 and 118 and scrim layer 126 with nylon tapes 124 laminated
between layers
112 and 114. Adhered to outer layer 112 is a metallized PET layer 12.
Figs. 15 and 16 represent the embodiment of Fig. 14 but, additionally, having
an
aluminum foil layer 122 laminated to layer 112 in Fig. 15 and to layer 118,
via a polyethylene
layer 136 in Fig. 16.
The following numerals denote the same materials throughout the drawings, as
follows:-
12 - 48 gauge aluminum metallized polyester (PET) film;
14 - adhesive;
16 - 1.2 ml polyethylene film;
18 - 2.0 ml polyethylene film (bubbled);
20 - 1.2 ml ethylene vinyl acetate - polyethylene film;
22 - 2.0 ml polyethylene film;
24 - aluminum foil;
26 - polyester scrim;
FR denotes 18% w/w antimony oxide fire retardant;
W denotes presence of TiO2 pigment (white).
The bubble pack layer is preferably of a thickness selected from 0.5 Cm to
1.25 cm.
The other polyethylene layers are each of a thickness, preferably, selected
from 1 to 6mls.
The fire retardant material of use in the preferred embodiments was antimony
oxide at
a concentration selected from 10-20% w/w.
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Insulation material No. 1 was a prior art commercial single bubble pack
assembly of a
white polyethylene film (1.2 mil) laminated to a polyethylene bubble (2.0 mil)
on one side
and aluminum foil (0.275 mil) on the other.
Insulation material No. 2 was a metallized polymeric material of use in the
practise of
the invention in the form of a bubble pack as for material No. 1 but with the
aluminum foil
substituted with metallized aluminum on polyethylene terephthalate (PET) film
(48 gauge)
adhered to the polyethylene bubble.
Test
A blow torch was located about 10 - 15 cm away from the insulation material (5
cm x
10 cm square) and directed at each of the aluminum surfaces.
Results
Single Bubble Aluminum Foil. Material No.l started to burn immediately and
continued burning until all organic material was gone. Flame and smoke were
extensive.
Single Bubble Metallized Aluminum Material. For material No. 2, where the
flame was
directly located, a hole was produced. However, the flame did not spread
outwards of the
hole or continue to burn the material. Flame and smoke were minimal.
C'onclusion. Single Bubble metallized material reacts better to the flame,
that is the material
burned where the flame was situated but did not continue to burn.
Clearly, this test shows the advance of the metallized insulation material
according to
the invention over its prior art aluminum foil counterpart.
EXAMPLES I AND 2 UNDERWENT FULL ROOM BURN TESTS
EXAMPLE l
This Example illustrates the testing of the bubble-pack assembly shown in Fig.
1-
being commonly known as a metallized-double bubble-white poly (FR) in
accordance with
NFPA 286 Standard Methods of Fire Tests for Evaluating Contribution of Wall
and Ceiling
Interior Finish to Room Fire Growth. The test material was mounted on the LHS,
rear, RHS
walls to a height of the test room as well as the ceiling of the test room.
The sample did not
spread flames to the ceiling during the 40 kW exposure. The flames did not
spread to the
extremities of the walls during the 160 kW exposure. The sample did not
exhibit flashover
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conditions during the test. NFPA 286 does not publish pass/fail criteria. This
specimen did
meet the criteria set forth in the 2003 IBC Section 803.2.1.
The test was performed by Intertek Testing Services NA, Inc., Elmendorf,
Texas,
78112 - 984; U.S.A.
This method is used to evaluate the flammability characteristics of finish
wall and
ceiling coverings when such materials constitute the exposed interior surfaces
of buildings.
The test method does not apply to fabric covered less then ceiling height
partitions used in
open building interiors. Freestanding panel furniture systems include all
freestanding panels
that provide visual and/or acoustical separation and are intended to be used
to divide space
and may support components to form complete work stations. Demountable,
relocatable,
full-height partitions include demountable, relocatable, full-height
partitions that fill the space
between the finished floor and the finished ceiling.
This fire test measures certain fire performance characteristics of finish
wall and
ceiling covering materials in an enclosure under specified fire exposure
conditions. It
determines the extent to which the finish covering materials may contribute to
fire growth in
a room and the potential for fire spread beyond the room under the particular
conditions
simulated. The test indicates the maximum extent of fire growth in a room, the
rate of heat
release, and if they occur, the time to flashover and the time to flame
extension beyond the
doorway following flashover.
General Procedure
A calibration test is run within 30 days of testing any material as specified
in the
standard. All instrumentation is zeroed, spanned and calibrated prior to
testing. The
specimen is installed and the diffusion burner is placed. The collection hood
exhaust duct
blower is turned on and an initial flow is established. The gas sampling pump
is turned on
and the flow rate is adjusted. When all instruments are reading steady state
conditions, the
computer data acquisition system and video equipment is started. Ambient data
is taken then
the burner is ignited at a fuel flow rate that is known to produce 40 kW of
heat output. This
level is maintained for five minutes at which time the fuel flow is increased
to the 160 kW
level for a 10-minute period. During the burn period, all temperature, heat
release and heat
flux data is being recorded every 6 seconds. At the end of the fifteen minute
burn period, the
14
CA 02554754 2007-01-12
= ~ _ burner is shut off and all instrument readings are stopped. Post test
observations are made
and this concludes the test.
All damage was documented after the test was over, using descriptions,
photographs
and drawings, as was appropriate.
Digital color photographs and DV video taping were both used to record and
documents the test. Care was taken to position the photographic equipment so
as to not
interfere with the smooth flow of air into the test room.
The test specimen was a metallized/double bubble/white poly (FR) insulation.
Each
panel measured approximately 4 ft. wide x 8 ft. tall x 1/8 in. thick. Each
panel was white in
color. The insulation was positioned using metal C studs every 2 ft. o.c. with
the flat side of
the stud facing the interior of the room. The insulation was attached to the C
studs using
screws and washers.
All joints and corners in the room were sealed to an airtight condition using
gypsum
drywall joint compound and/or ceramic fiber insulation.
The data acquisition system was started and allowed to collect ambient data
prior to
igniting the burner and establishing a gas flow equivalent to 40 kW for the
first 5 minutes and
160 kW for the next 10 minutes. Events during the test are described below:
CA 02554754 2006-08-23
TIME
(min:sec) OBSERVATION
0:00 Ignition of the burner at a level of 40 kW.
0:20 Specimen surface began to melt.
0:45 The specimen began to melt at 4 ft. above the specimen.
0:55 Ignition of the specimen at the melting edge.
1:25 Melting of the specimen at 8 ft. above the test burner.
3:20 Ignition of the specimen at the RHS edge of melt pattern.
3:38 Flaming drops began to fall from the specimen.
4:00 Burning on metal side of specimen only.
5:00 Burner output increased to 160 kW.
5:18 Specimen began to rapidly melt away.
5:25 The specimen began to melt away at 6 ft. from the test corner.
6:20 No burning of the specimen observed.
8:20 Material fell in front of the doorway.
9:00 TC # 5 fell in front of the doorway.
12:00 No new activity.
14:00 No changes observed in the specimen.
15:00 Test terminated.
Post Test Observations:
The specimen was completely melted on the top portions along all three walls.
On the
lower LHS wall, the specimen was still intact and appeared to have no visible
damage. The
lower rear wall appeared to have melting 4 ft. from the test corner, with the
specimen intact
from 4-8 ft from the test corner. The lower RHS wall was melted 4 ft. from the
test corner
and appeared intact from 4 ft. to the doorway. The specimen on the ceiling
panels was
observed to have been 100% melted.
16
CA 02554754 2006-08-23
Conclusion
The sample submitted, installed, and tested as described in this report
displayed low
levels of heat release, and upper level temperatures. The sample did not
spread flames to the
ceiling during the 40 kW exposure. The flames did not spread to the
extremities of the 12-
foot walls during the 106 kW exposure. The sample did not exhibit flashover
conditions
during the test. NFPA 286 does not publish pass/fail criteria. One must
consult the codes to
determine pass fail. This specimen did meet the criteria set forth in the 2003
IBC Section
803.2.1.
EXAMPLE 2
The test described under Example I was repeated but with a metallized double
bubble/white poly not containing fire retardant as shown in Fig. 2.
The sample did not spread flames to ceiling during the 40 kW exposure. The
flames
did spread to the extremities of the walls during the 106 kW exposure. The
sample did not
exhibit flashover conditions during the test. NFPA 286 does not publish
pass/fail criteria.
However, this specimen did not meet the criteria set forth in the 2003 IBC
Section 803.2.1.
Events during the test are described below:
17
CA 02554754 2006-08-23
TIME
min:sec OBSERVATION
0:00 Ignition of the burner at a level of 40 kW.
0:14 Specimen surface began to melt.
0:20 The edge of the specimen ignited.
0:38 The specimen began to melt 6 - 7 ft. above the burner/flaming
drops began to fall from the specimen.
1:21 Flame spread at 2 ft. horizontally at 4 ft. above the test burner.
2:31 Flame spread at 4 ft. horizontally at 4 ft. above the test burner.
3:50 The specimen on the ceiling began to fall.
4:24 The specimen began to fall from the corners and ceiling.
5:00 Burner output increased to 160 kW/specimen continuing to fall.
5:57 Flame spread at 6 ft. horizontally at the bottom of the 8ft. wall.
7:10 Flames reached 8 ft. along the 8 ft. wall.
8:38 Flames on the LHS wall reached 10 ft. from the test corner.
9:40 Flames on the LHS wall reached 12 ft. extremity.
10:38 Test terminated.
Post Test Observations:
The specimen was 100% melted from the C studs along all the walls. The gypsum
board behind the specimen was flame bleached and charred in the test corner.
Along the rear
wall, the bottom of the wall was charred the length of the wall. On the RHS
wall, 5 ft. of
specimen was still intact near the doorway. The insulation on the LHS wall was
melted
completely with the exception of a small 2 ft. section attached to the C stud
near the doorway.
The insulation on the ceiling was 100% melted exposing the C studs.
18
CA 02554754 2006-08-23
Conclusion
The sample submitted, installed, and tested as described in this report
displayed low
levels of heat release, and upper level temperatures. The sample did not
spread flames to the
ceiling during the 40 kW exposure. The flames did spread to the extremities of
the 12-foot
walls during the 160 kW exposure. The sample did not exhibit flashover
conditions during
the test. NFPA 286 does not publish pass/fail criteria. One must consult the
codes to
determine pass-fail. This specimen did not meet the very strict criteria set
forth in the 2003
IBC Section 803.2.1.
TEST STANDARD METHOD - ASTME 84-05
Examples 3-6 underwent tests carried out in accordance with Test Standard
Method
ASTME84-05 for Surface Burning Characteristics of Building Materials, (also
published
under the following designations ANSI 2.5; NFPA 255; UBC 8-1 (42-1); and
UL723).
The method is for determining the comparative surface burning behaviour of
building
materials. This test is applicable to exposed surfaces, such as ceilings or
walls, provided that
the material or assembly of materials, by its own structural quality or the
manner in which it
is tested and intended for use, is capable of supporting itself in position or
being supported
during the test period.
The purpose of the method is to determine the relative burning behaviour of
the
material by observing the flame spread along the specimen. Flame spread and
smoke density
developed are reported. However, there is not necessarily a relationship
between these two
measurements.
It should be noted that the use of supporting materials on the underside of
the test
specimen may lower the flame spread index from that which might be obtained if
the
specimen could be tested without such support. This method may not be
appropriate for
obtaining comparative surface burning behaviour of some cellular plastic
materials. Testing
of materials that melt, drip, or delaminate to such a degree that the
continuity of the flame
front is destroyed, results in low flame spread indices that do not relate
directly to indices
obtained by testing materials that remain in place.
19
CA 02554754 2006-08-23
Table 1 gives detailed observations for the experiments conducted in Examples
3
to 15.
EXAMPLE 3
The test specimen consisted of (3) 8 ft. long x 24 in. wide x 1.398 in. thick
17.50 lbs
metallized/double bubble/white poly (No-FR) reflective insulation, assembly of
Fig. 2
secured to 1.75 in. wide x 1 in. thick, aluminum frames using 3/4 in. long,
self-drilling, hex
head screws and washers. The nominal thickness of the reflective insulation
was 5/16 in.
thick. The white poly was facing the flames during the test. The specimen was
self-
supporting and was placed directly on the inner ledges of the tunnel.
The test results, computed on the basis of observed flame front advance and
electronic
smoke density measurements were as follows.
Flame Spread Smoke
Test Specimen Index Developed Index
Mineral Fiber Cement Board 0 0
Red Oak Flooring 85 75
Test Specimen 5 5
This metallized-double bubble-white poly having no fire-retardant assembly of
Fig. 2
was most acceptable in this E84-05 test to permit use in Class A buildings.
During the test, the specimen was observed to behave in the following manner:
The white poly facer began to melt at 0:05 (min:sec). The specimen ignited at
0:07
(min:sec). The insulation began to fall from the aluminum frames at 0:08
(min.sec.). The
test continued for the 10:00 duration. After the test burners were turned off,
a 60 second after
flame was observed.
After the test the specimen was observed to be damaged as follows:
The specimen was consumed from 0 ft.- 9 ft. The white poly facer was melted
from 19 ft. -
24 ft.
CA 02554754 2006-08-23
EXAMPLE 4
This embodiment is a repeat of Example 3, but with a metallized/single
bubble/white
poly (No-FR) reflective insulation assembly as shown in Fig. 3 substituted for
the material
described in Example 3.
Specimen Description
The specimen consisted of (3) 8 ft. long x 24 in. wide x 1.100 in. thick 16.60
lbs
nietallized/single bubble/white poly (No-FR) reflective insulation, secured to
1.75 in. wide x
1 in. thick, aluminum frames using 3/4 in. long, self-drilling, hex head
screws and washers.
The nominal thickness of the reflective insulation was 3/16 in. thick. The
white poly was
facing the test burners. The specimen was self-supporting and was placed
directly on the
inner ledges of the tunnel.
Flame Spread Smoke
Test Material Index Developed Index
Mineral Fiber Cement Board 0 0
Red Oak Flooring 85 75
Specimen 5 0
During the test, the specimen was observed to behave in the following manner:
The poly facer began to melt at 0:03 (min/sec). The poly facer ignited at 0:06
(min:sec).
The insulation began to fall from the aluminum frames at 0:07 (min:sec). The
insulation
ignited on the floor of the apparatus at 0:07 (min:sec). The test continued
for the 10:00
duration.
After the test the specimen was observed to be damaged as follows:
The insulation was consumed from 0 ft. - 20 ft. The poly facer was melted from
20 ft. - 24
ft. The polyethylene bubbles were melted from 20 ft. to 24 ft.
21
CA 02554754 2006-08-23
EXAMPLE 5
This embodiment is a repeat of Example 3, but with a metallized/double
bubble/metallized (No FR) reflective insulation substituted for the material
described in
Example 3.
Specimen Description
The specimen consisted of (3) 8 ft. long x 24 in. wide x 1.230 in. thick 17.40
lbs
metallized/double bubble/metallized no FR reflective insulation assembly of
Fig. 4, secured
to 1.75 in. wide x 1 in. thick, aluminum frames using 3/4 in. long, self-
drilling, hex head
screws and washers. The nominal thickness of the reflective insulation was
5/16 in. thick.
The specimen was self-supporting and was placed directly on the inner ledges
of the tunnel.
Flame Spread Smoke
1'est Material Index Developed Index
Mineral Fiber Cement Board 0 0
Red Oak Flooring 85 75
Test Specimen 5 5
During the test, the specimen was observed to behave in the following manner:
The metallized insulation began to melt at 0:06 (min:sec). The metallized
insulation began to
fall from the aluminum frame at 0:10 (min.sec.). The metallized insulation
ignited at 0:11
(min.sec). The test continued for the 10:00 duration. After the test burners
were turned off, a
19 second after flame was observed.
After the test, the specimen was observed to be damaged as follows:
The metallized insulation was consumed from 0 ft. - 16 ft. The polyethylene
bubbles were
melted from 16 ft. - 24 ft. Light discoloration was observed to the metallized
facer from 16
ft. - 24 ft.
This metallized-double bubble-metallized assembly of Fig. 4 met the E84
standard for
building reflective insulation.
22
CA 02554754 2006-08-23
EXAMPLE 6
This embodiment is a repeat of Example 5, but with a metallized/double
bubble/metallized (FR) reflective insulation assembly as seen in Fig. 5
substituted for the
material described in Example 5, Fig. 4.
The specimen consisted of (3) 8 ft. long x 24 in. wide x 1.325 in. thick 17.70
lbs
nletallized/double bubble/metallized (FR) reflective insulation assembly,
secured to 1.75 in.
wide x 1 in. thick, aluminum frames using 3/4 in. long, self-drilling, hex
head screws and
washers. The nominal thickness of the reflective insulation was 5/16 in.
thick.
Flame Spread Smoke
Test Materials Index Developed Index
Mineral Fiber Cement Board 0 0
Red Oak Flooring 85 75
T'est Specimen 5 15
During the test, the specimen was observed to behave in the following manner:
The metallized facer began to melt at 0:04 (min:sec.). The specimen ignited at
0:06
(min:sec.). The metallized insulation began to fall from the aluminum frames
at 0:11
(min:sec). The floor of the apparatus ignited at 6:41 (min:sec). The test
continued for the
10:00 duration. After the test burners were turned off, a 60 second after
flame was observed.
After the test the specimen was observed to be damaged as follows:
The insulation was consumed from 0 ft. - 16 ft. The polyethylene bubbles were
melted from
16 ft. - 24 ft. Light discoloration was observed to the metallized facer from
16 ft. - 24 ft.
The metallized-double bubble-metallized (FR) reflective insulation assembly of
Fig. 5
passed this ASTM E84-05 test for Class A building insulation.
In the following embodiments Examples 7-9, less stringent ASTM E84 test
conditions
were employed.
23
CA 02554754 2006-08-23
EXAMPLE 7
An aluminum foil-single bubble-aluminum foil/poly with polyester scrim
reflective
insulation assembly, without a fire-retardant was stapled to three 2 x 8 ft.
wood frames with
L-bars spaced every 5 feet O.C. was tested. The reflective insulation was
secured to the L-
bars by using self-drilling screws.
Flame Spread Index 50
Smoke Developed Index 50
This material failed this ASTM E84 test.
EXAMPLE 8
Aluminum foil-single bubble-aluminum foil with fire-retardant reflective
insulation
assembly was stapled to (3) 2 x 8 ft. wood frames, L-bar cross members on 5
ft. centers,
stapled to wood on sides and screwed to L-bar. The sample was self-supporting.
This
assembly as shown in Fig. 7, failed this E84 test conditions for building
insulations, for
having a flame spread index of 55 and a smoke developed index of 30.
EXAMPLE 9
Aluminum foil-single bubble-white poly (FR) as shown in Fig. 8 was attached to
nominal 2 x 2 wood frames with L-bar cross members spaced every 5 ft. O.C. The
sample
was self-supporting.
The specimen had a flame speed index of 65 and a smoke developed index of 75
to
not be acceptable as Class A building material.
The following embodiments describe ASTM 84-05e1 Surface Burning
Characteristics
of Building Materials.
24
CA 02554754 2006-08-23
EXAMPLE 10
The following modified ASTM E84-05el test was designed to determine the
relative
surface burning characteristics of materials under specific test conditions.
Results are again
expressed in terms of flame spread index (FSI) and smoke developed (SD).
Summary of Test Procedure
The tunnel was preheated to 150 F, as measured by the floor-embedded
thermocouple
located 23.25 feet downstream of the burner ports, and allowed to cool to 105
F, as measured
by the floor-embedded thermocouple located 13 ft. from the burners. At this
time, the tunnel
lid was raised and the test sample placed along the ledges of the tunnel so as
to form a
continuous ceiling 24 ft. long, 12 inches. above the floor. The lid was then
lowered into
place.
Upon ignition of the gas burners, the flame spread distance was observed and
recorded every 15 seconds. Flame spread distance versus time is plotted
ignoring any flame
front recessions. If the area under the curve (A) is less than or equal to
97.5 min.-ft., FSI =
0.515 A; if greater, FSI = 4900/(195-A). Smoke developed is determined by
comparing the
area under the obscuration curve for the test sample to that of inorganic
reinforced cement
board and red oak, arbitrarily established as 0 and 100, respectively.
The reflective insulation was a metallized-double bubble-metallized assembly
with
fire-retardant, as shown in Fig. 9. The material had a very acceptable OFSI
and 85 SD.
Observations of Burning Characteristics
The sample began to ignite and propagate flame immediately upon exposure to
the
test flame.
The sample did not propagate past the base line.
Maximum amounts of smoke developed were recorded during the early states of
the
test.
CA 02554754 2006-08-23
EXAMPLE 11
The test conditions were as for Example 10 but carried out with a
metallized/bubble/single bubble, white (FR) as shown in Fig. 10, substituted
for the material
of Example 10.
The white face was exposed to the flame source . The material had a very
acceptable
0 FSI and 65 DS.
Observations of Burning Characteristics
The sample began to ignite and propagate flame immediately upon exposure to
the
test flame.
The sample did not afford a flame front propagation.
Maximum amounts of smoke developed were recorded during the early states of
the
test.
EXAMPLE 12
The test conditions were as for Example 10 but carried out with a metallized-
single
bubble as shown in Fig. 11, substitute for the material of Example 10.
The test material had a very accept 0 FSI and 30 SD.
Observations of Burning Characteristics
The sample began to ignite and propagate flame immediately upon exposure to
the
test flame.
The sample did not afford a flame front propagation.
Maximum amounts of smoke developed were recorded during the early states of
the
test.
EXAMPLE 13
The test conditions were as for Examples 7-9, with a self-supporting aluminum
foil-
single bubble containing fire retardant as shown in Fig. 12. An unacceptable
FSI of 30 and a
SDI of 65 was observed.
26
CA 02554754 2006-08-23
EXAMPLE 14
The test was conducted under ASTM E84-OOa Conditions in January 22, 2002, with
layers of aluminum foil-double bubble-aluminum foil, according to the prior
art as shown in
Fig. 13. The specimen consisted of a 24" wide x 24' long x 5/16" thick
(nominal) 3.06 lbs
sheet of reflective insulation - foil / double PE bubble / foil. The specimen
was tested with a
1/8" wide x 24' long second of the foil facer removed from the center to
expose the core
material directly to the flames.
RESULTS
7'est Specimen Flame Spread Smoke Developed
Index Index
Mineral Fiber Cement Board 0 0
Red Oak Flooring n/a 100
Sample 115 20
During the test, the specimen was observed to behave in the following manner:
Steady ignition began at 0:35 (min:sec). Flaming drops began to fall from the
specimen at
0:45 and a floor flame began burning at 0:46. The test continued for the 10:00
duration.
Upon completion of the test, the methane test burners were turned off and an
after flame
continued to burn for 0:19.
After the test, the specimen was observed to be damaged in the following
manner:
The specimen was slightly burned through from 1 ft. to 3 ft. The PE bubble was
melted from
0 ft. to 24 ft. and the foil facer had a black discoloration on it from 2 ft.
to 24 ft.
The sample was supported on '/4" steel rods and 2" galvanized hexagonal wire
mesh
id not meet the criteria see for this E84-OOa test for a building insulation.
EXAMPLE 15
This example was a repeat of Example 14.
27
CA 02554754 2006-08-23
RESULTS
Test Specimen Flame Spread Smoke Developed
Index Index
Mineral Fiber Cement Board 0 0
Red Oak Flooring n/a 100
Sample 65 35
During the test, the specimen was observed to behave in the following manner:
Steady ignition began at 0:54 (min:sec). Flaming drops began to fall from the
specimen at
0:58 and a floor flame began burning at 1:03. The test continued for the 10:00
duration.
After the test, the specimen was observed to be damaged as follows:
The foil was 80% consumed from I ft. to 3 ft. and lightly discoloured from 3
ft. to 24 ft. The
bubble core was melted/collapsed from 0 ft. to 24 ft.
Although the results were an improvement over Example 14 material, they were
still
not satisfactory.
28
CA 02554754 2006-08-23
TABLE
EXAMPLE 3 4 5 6 7 8 9 13 14 15
Specimen
Data
Time to 7 6 11 6 7 32 8 9 35 54
Ignition (sec.)
T'ime to Max 23 22 26 23 64 81 38 28 284 191
FS (see.)
Maximum FS 0.6 0.8 0.6 1.0 10.7 11.8 12.1 5.5 19.5 14.5
(feet)
T'ime to 980 F NR NR NR NR NR NR NR NR NR NR
(sec)
Max 447 416 482 476 470 561 582 520 728 711
T'emperature
( F)
Time to Max 597 600 596 565 599 82 48 594 316 127
T'emperature
(sec)
T'otal Fuel 51.44 51.26 51.57 51.17 50.75 50.65 50.81 50.61 39.47 35.82
Burned (cubic
feet)
FS* Time 6.0 7.4 6.2 9.6 99.8 104.2 117.1 53.5 153.1 121.0
Area (ft* min)
Smoke Area 2.3 1.1 3.2 10.8 41.7 26.5 65.0 53.4 22.2 33.4
('YoA* min)
Fuel Area 3971.3 3668.6 4283.0 4324.4 4271.2 5035.3 5032.7 4554 5608.3 5556.9
( F* min)
Fuel 0 0 0 0 0 0 0 0 9 8
C'ontributed
Value
LJnrounded 3.1 3.8 3.2 4.9 51.5 54.0 62.9 27.5 117.0 66.2
FSI
*Never
Reached
Calibration
Data
T'ime to 44 44 44 44 41 41 41 41 50 55
Ignition of
Last Red Oak
(sec.)
Red Oak 62.50 62.50 62.50 62.50 85.0 85.0 85 85 100.00 101.02
Smoke Area
(%A* min)
Red Oak Fuel 8972 8972 8972 8972 8128 8128 8128 8128 8548 9763
Area ( F*
min)
Glass Fiber 5065 5065 5065 5065 5443 5443 5443 5443 5311 5178
Board Fuel
Area ( F*
min)
29
CA 02554754 2006-08-23
EXAMPLE 16
Standard Surface Emittance (reflectivity) tests (ASTM C 1371-04a - "Standard
Test
Method for Determination of Emittance of Materials near Room Temperature Using
Portable
Emissometers") with the embodiments shown in Fig. 3 and Fig. 17 gave a
measured
emittance of 0.30 (65% reflectance) for the dull surface of the metallized
coated PET material
and a value of 0.06 (96% reflectance) for the shiny surface.
The 0.5 ml thick lacquer coated metallized coated PET surface also gave an
acceptable reflectance of 96%.
The lacquer layer 150 provides suitable, anti-corrosion protection.
Although this disclosure has described and illustrated certain preferred
embodiments
of the invention, it is to be understood that the invention is not restricted
to those particular
embodiments. Rather, the invention includes all embodiments, which are
functional or
niechanical equivalence of the specific embodiments and features that have
been described
and illustrated.
