Note : Les descriptions sont présentées dans la langue officielle dans laquelle elles ont été soumises.
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FIRE-RETARDANT MATTRESS
Background of the Invention
The systems and methods described herein relate to fire retardant mattresses
and
methods for manufacturing fire retardant mattresses.
In general, mattresses are manufactured by covering an assembly of coil
springs with a
combination of polyurethane form and/or matting which is then enclosed in a
cover
ticking or other material. This combination provides a light durable and
comfortable
mattress at a reasonable cost.
to
Every home, hotel, dormitory, hospital and many other facilities have several
to
dozens of mattresses, and mattresses tend to be large items that are kept in
mainly
living areas. Recently, fire prevention efforts have directed some attention
to
developing new mattresses that have a reduced likelihood to catch on fire or
burn
1s during a fire. To this end, mattress manufacturers have developed a number
of
different fire retardant mattresses, each of which offers some benefits for
reducing the
likelihood that a fire will start or spread because the material used in the
construction
of a mattress represents a large amount of fuel able to support that fire.
2o For example, bed pads have been developed that can be placed on top of a
bed and
cover the sides of a bed. These bed pads are generally made of fire retardant
materials
that protect the mattress from exposure to a flame or heat and tend to reduce
the
likeliness that the mattress will catch on fire. Although these bed pads have
been
effective, they are uncomfortable and unsightly. Consequently consumers have a
2s tendency to remove these bed pads after a period of time and once removed
the
efficacy of the bed pad is negated.
To address this issue, other mattress manufacturer have developed mattresses
that
have flame and/or fire retardant material built into the mattress cover.
Typically, these
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fire retardant materials include fiberglass, asbestos, or metal foil and work
well in
reducing the lilcelihood that the mattress will catch on fire. However, these
materials
are uncomfortable to sleep on and are therefore disfavored by consumers. Metal
foils
made of, for example aluminum, have several drawbacks, such as a limited
breathability of the fabric and a reduced cushioning aspect of the upholstered
article.
Other these materials have a tendency to dry out, to become flaky, and to
ultimately
brealc down, malting the visible sleeping surface if not unusable, so at least
unsightly.
Consequently, the life expectancy of a flame retardant mattress that includes
a layer of
fiberglass, asbestos and/or aluminum foil, can be significantly less than the
expectant
1o product life of a normal mattress.
Because of the need for changing the established mattress manufacturing
process to
accommodate the new materials and the perceived reluctance of consumers to
accept
the different feel and/or appearance of the sleeping surface, mattress
manufacturers
have so far been unmotivated to develop fire retardant mattresses.
Accordingly, there is a need in the art for a fn~e retardant mattress that is
facile to
manufacture, has competitive product life and provides the comfort and
durability
expected by consumers purchasing a mattress.
Summary of the Invention
The invention is directed to a fire-retardant quilt panel for a mattress and
to a fwe-
retardant mattress construction. The invention is fixrther directed to a
method for
manufacturing a fire-retardant mattress.
According to one aspect of the invention, a fire-retardant quilt panel for a
mattress
includes a mattress padding layer, an outer ticking forming a sleep surface,
and a fire
barrier fabric disposed between the mattress padding layer and the outer
ticking layer.
According to another aspect of the invention, a fire-retardant mattress
includes a
3o fi~ame, an upholstery topper layer adjacent to at least a top surface of
the frame, an
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outer ticking forniing a sleep surface, and a fire barrier fabric disposed
between the
upholstery topper layer and the outer ticking layer.
Embodiments of the invention may include one or more of the following
features. The
fire barrier fabric can be in direct contact with the outer ticking layer and
more
particularly can be affixed to the outer ticking layer, for example, by gluing
with an
adhesive or by stitching. The fire barrier fabric can also be placed
underneath the
border panel extending around the sides of the mattress frame. The quilt panel
advantageously is constructed to meet regulatory requirements for
flammability, such
to as the California Bureau of Home Furnishings Technical Bulletin 129
Flammability
Test Procedure.
According to yet another embodiment of the invention, a method of
manufacturing a
fire-retardant mattress includes the acts of providing a mattress frame,
placing an
15 upholstery topper layer adjacent to at least a top surface of the frame,
placing a fire
barrier fabric on the upholstery topper layer, and placing an outer ticking
over and in
direct contact with the fire barrier fabric, said outer ticking layer forming
a sleep
surface.
2o Further features and advantages of the present invention will be apparent
from the
following description of preferred embodiments and from the claims.
Brief Description of the Drawings
25 The following figures depict certain illustrative embodiments of the
invention in
which like reference numerals refer to like elements. These depicted
embodiments are
to be understood as illustrative of the invention and not as limiting in any
way.
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FIG. 1 is an illustrative partially exploded view of an innerspring
construction,
padding and ticking layers with a fire-barrier layer
FIGS. 2A and 2B show in greater detail exemplary embodiments of a mattress
cover
with a fire-barrier layer;
FIG. 3 shows the sample weight loss of the tested mattress during the test;
FIG. 4 shows the heat release rate of the tested mattress during the test; and
to
FIG. 5 shows the total heat release of the tested mattress during the test.
Description of the Illustrated Embodiments
15 A mattress construction with a quilted ticking is described that
incorporates an
effective fire-retardant barrier without changing the appearance and feel of
the
mattress sleeping surface. In particular, described herein are mattresses,
toppers and
methods for malting mattresses-that provide bedding products having improved
resistance to open flame ignition. Although the systems and methods described
herein
2o relate to mattress and other bedding products, it will be apparent to those
of sltill in
the art that other products may result from the methods described herein,
without
departing from the scope of the invention.
Referring first to FIG. 1, a mattress 10, shown here in a partially exploded
view,
25 consists of an innerspring indicated by reference numerals 11 and 13 having
at least
one upholstery topper layer 16, and a second optional layer 18 and at least
one quilt
layer 12 about the top and bottom surfaces of the innerspring. The level of
support and
comfort provided by such a mattress, often referred to as "firmness," is a
function of
both the number and characteristics of the upholstery topper and the quilting
panel
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layers about the top and bottom of the innerspring and of the performance
characteristics of the innerspring.
The innerspring (not shown in detail) generally comprises border wires forming
a
s rectangular structure and, within the structure, a plurality of
interconnected coil
springs. The coil springs are generally disposed in rows and columns over the
entire
area of the rectangular structure. When designing an innerspring, a number of
variables which affect innerspring performance must be taken into
consideration.
Some of these variables include the coil count, the coil density, the coil
shape, the
1 o number of turns of the coil, the gauge of the wire, the heat treatment of
the wire, the
technique used to assemble the innerspring, and the edge treatment. The
innerspring
construction may be an open-coil construction as illustrated, or may also be a
poclceted-coil type as identified in U.S. Pat. No. 4,234,933 to Stumpf, which
is
incorporated herein by reference. However, any suitable innerspring or
innercore
15 may be employed. For example, the innercore may be foam, latex, open coil,
pocketed coil, or a combination thereof. The size of the innercore may vary
according
the application and for example, may support the entire sleeping surface, or
may be
somewhat smaller and provide space for one or more edge supports that sit at
the
peripheral edge of the mattress. Examples of edge supports may include foam
rails
2o placed along the side of the mattress or pocketed springs having a selected
firmness.
As depicted, each upholstery topper layer commonly includes an insulating
layer 18 of
material in direct contact with the innerspring 11 which may mask or insulate
from the
sleeper the noise produced by the interaction between the components of the
25 innerspring and also to prevent softer upholstery materials from falling or
pocketing
into the innerspring. This insulating layer 18 can be constructed of, for
example, wire
mesh, plastic mesh, woven fabric, or non-woven fabric, or any suitable
material. Each
upholstery topper layer can further include a layer of padding material 16
which
affects the firmness of the mattress. This layer of padding material may be
located
3o directly adjacent to the insulating layer 18 and can be constructed of
natural fibers
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such as, for example, cotton, synthetic fibers, foam, or a fiber/foam
combination. It
should be understood that additional layers of padding can be provided for
each
upholstery topper layer, the number of padding layers depending upon the
comfort
level and quality of the mattress. The upper layer or the topper may include a
layer 14
of a woven material that adds to the firmness of the mattress 10.
As shown in more detail in FIG. 2A, a quilt panel layer 21 is provided
adjacent to
each upholstery layer 28. The quilt panel layer 21 of the mattress 10 provides
the
direct contact with the sleeper and thus the immediate perception of softness
or "feel."
Each quilt panel layer 21 commonly includes a layer of mesh or cloth bottom or
backing material 28, a layer of foam material 26 positioned over the backing
material
28, a layer of fiber or filler material (quilt fill) may optionally be
positioned over the
foam 26, and finally a layer of ticking forming the cover 22. The number of
layers of
foam and quilt fill 26 in the quilt panel layer can vary depending on the
desired
1 s comfort level, quality, and expense of the mattress. The entire layer can
be stitched
together, typically in a conventional quilting machine (not shown) with thread
to form
a quilt pattern. The quilt pattern holds the components of the layer together
and
provides a composite structure to the quilt panel layer.
2o In the exemplary fire-retardant mattress, a fire barrier fabric 24 which
can be
incorporated in the quilt panel structure 21 during the quilting operation is
interposed
between the layer of fiber or filler material 26 and the ticlcing 22. The
ticking layer 22
may be a conventional ticking layer, or a layer of lace, cotton fabric or any
other
suitable material. The fire barrier fabric 24 can also be attached to one of
the layers,
2s for example, the cover, with an adhesive, or bonded in some other way to
the lower
surface of the ticking 22. The fire barrier fabric 24, when used as the
backing material,
can significantly reduce the fire hazard due to the material properties of the
fire barrier
fabric 24 that will hinder the propagation of a fire to the entire mattress
body. For
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added fire protection, the fire barrier fabric 24 can also be placed directly
under the
border ticking layer.
As described above, the fire barrier layer 24, in any embodiment, may be
applied to
the top surface, as well as the border panels, including header and footer and
optionally, the lower surface.
FIG. 2B depicts an alternate embodiment of the mattresses described herein. In
particular, FIG. 2B depicts a mattress topper 21 that includes a foam/fill
layer 26 that
is disposed between two opposing layers of ticking 22 and two opposing layers
of fire
1o barrier material 24. The mattress topper 21 depicted in FIG. 2B may be a
pillow top
topper of the type commonly attached to the upper surface of a mattress,
including a
mattress 10 having a fire barrier layer disposed beneath the ticking layer 22
on the
exterior surface of the mattress. As described with reference to FIG. 2B, the
fire
barrier layers 22, may be stitched, glued or other wise bonded to the ticking
layer, to
~ 5 facilitate providing a quitable layer of material that provides for a
mattress tops that
meets the aesthetic expectations of the consumer. The joining of the fire
barrier and
the ticking material forms a laminate that reduces the likelihood that an open
flame
will ignite the inner material of the mattress 10, and at the same time
provides a
cosmetically appealing exterior surface.
2o The exemplary quilted mattress cover depicted in FIGS. 2A and 2B and tested
in the
manner described below included Ultrawool, 3/4 " P7L and 3/8 " P34 polyester
over 1
3/4 " convoluted foam, as well as 1/2" P-34 Poly and S4-FI fiber next to the
coil unit.
The dimensions of the tested mattress were 38" x 741/2" with a total mattress
weight
of 46 lbs. The fire blocking layer consists of Firegard~ LWB, sold by Chiquola
2s Industrial Products, LLC, Honea Path, SC, USA, and extends over the
mattress panels
and the borders.
The flammability of the outer ticking was tested under the California Bureau
of Home
Furnishings Technical Bulletin 129 Flammability Test Procedure for Mattresses
for
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Use in Public Buildings. The purpose of this test method is to determine the
burning
behavior of mattresses used in public occupancies by measuring specific fire-
test
responses when the mattress is subjected to a specified flaming ignition
source under
well ventilated conditions. A mattress fails to meet the requirements of this
test
s procedure if any of the following criteria are exceeded: (1) weight loss due
to
combustion of 3 pounds or greater in the first 10 minutes of the test; (2) a
maximum
rate of heat release of 100 kW or greater; or (3) a total heat release of 25
MJ or greater
in the first 10 minutes of the test. The type of ignition chosen (flaming
source) is
common in both accidental and intentional fires, for example, ignition by
cigarettes.
to The recorded test data typically include room smoke opacity; weight loss;
smoke
release rate; total smoke release; carbon monoxide concentration; heat release
rate;
total heat release; and temperature measurements above and around the
mattress.
The fire was simulated by placing a propane burner centrally and parallel to
the
~s bottom horizontal surface at a distance of 1" from the vertical side panel
of the
mattress. The burner was allowed to burn for 180 seconds. Two seconds after
the test
started, the mattress ticking material started to melt and ignited after 4
seconds. A
little more than 1 minute after the start of the test, molten ticking started
to drip onto
the floor. Flames ceased 6 minutes into the test, and after 17 minutes all
smoke and
2o smoldering ceased.
FIG. 3 depicts graphically the weight loss in lbs of the exemplary tested fire-
retardant
mattress during the test duration of 18 minutes. The total weight loss 10
minutes into
the test is less than 0.1 1b, which is significantly smaller than the maximum
total
25 weight loss of 3 lbs permissible under the Bulletin 129 test procedure.
FIG. 4 shows a graph of the heat release rate in kW for the same mattress
during the
test. The maximum heat of approximately 151cW is released 2.5 minutes into the
test.
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Again, this value is significantly smaller than the maximum rate of heat
release of 100
1cW permissible under the Bulletin 129 test procedure.
FIG. 5 shows a graph of the total heat release in MJ during the same test. The
total
heat release during the first 10 minutes into the test is 2.75 MJ, which is
significantly
smaller than the maximum heat release of 25 MJ permissible under the Bulletin
129
test procedure.
The other recorded test data (e.g., temperature, carbon monoxide, smoke and
toxic
gas released) were also all significantly smaller than the maximum values
permitted
under the Bulletin 129 test procedure.
In summary, mattresses constructed with a fire barrier fabric placed between
the quilt
panel layer and the ticking that provides direct contact with the sleeper as
well as
1s underneath the border panel have been shown to withstand ignition and
combustion
by open fire and exceed the requirements of the rigorous California Bureau of
Home
Furnishings Technical Bulletin 129 Flammability Test Procedure.
While the invention has been disclosed in connection with the preferred
embodiments
shown and described in detail, various modifications and improvements thereon
will
2o become readily apparent to those skilled in the art. For example, the fire
barrier fabric
can be applied directly behind the standard ticleing material with an adhesive
or
stitched or quilted, either with standard threads or with fire-retardant
threads.
Additionally, the barrier material can be used to replace current materials
such as a
bottom cover for non-flip products, a top panel for foundations, and/or a
complete, or
2s partial wrap-around cover for foundations. Additionally, in other
embodiments,
barrier materials can be used as the sole filling material beneath the fabric.
Further,
the systems and methods described herein may be employed with mattresses for
conventional beds, day beds, futons and other bedding applications. The
mattresses
may be two-sided or one sided. In the case of one-sided mattresses, the
sleeping
3o surface may comprise a an upper sleeping surface with a topper as described
above
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with reference to FIG. 2. The lower mattress surface, may be formed of a foam
padding selected to minimize compaction, and may be a high density
polyurethane
foam. This provides a relatively rigid bottom layer, that provides a non-
sleeping
surface. Although foam is often employed, other rigid materials may be used in
place
s of the foam layer, such as plastic, wood, or other nonyielding rigid
materials. To the
extent such materials for the lower layer yield to pressure, such materials
must have at
least a high degree of recoverability once the pressure has been removed so
that the
materials are not compacted. Other means known in the art for assembling a
mattress
can also be used when incorporating the fire barrier fabric. Accordingly, the
spirit and
1o scope of the present invention is to be limited only by the following
claims.
to
