Note: Descriptions are shown in the official language in which they were submitted.
W~ 94/00043 ~ I~ ~ ~p ~~ ~~ ~~ P~'T/C~93100275
Cd~IRPET C~NST~tUCTION
FIELD OF THE II~T~'ENTION
This invention relates to a new carpet
construction and particularly to a carpet for use with a
hook and loop installation device.
Ea~CRGROtJIeID OF TFiE TN~T'EN°~IO~T
As shown in my U.S. Patent x,822,658, I have
found that it is possible to produce a new carpet to be
installed, as for instance in wall to wall carpeting, by
the,use of a hook and loop system. With this previous
invention, in the preferred embodiment, a carpet is
manufactured with an undersurface substantially covered
with loops, and this carpet is installed with a
complementary tape containing hooks which are
temporarily covered. The tapes are put in place on the
floor and along the edges at intervals corresponding to
the width of the carpet or wherever additional
affixation to the floor is required. The tapes are
covered so that they do not pre-maturely attach to the
loops when the carpet is put in place, cut and fitted.
The tape covering is then pulled off to expose the hooks
and to adhere the carpet to the floor.
My earlier patent also discloses the
possibility of incorporating a foam layer between the
primary layer containing the carpet tufts and the
uriderlying~looped backing.
My earlier patent 4,822,658 shows a carpet
with a foam interposed layer. In-line lamination can
work to achieve a carpet construction as shown in
4,822,658. In such process, the bottom loop layer is
laminated onto the foam while the foam is formed onto
the layer so that the foam cures on the back of the
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carpet resulting in attachment of the underloop layer to
the top tufted layer of the carpet.
t
A principle drawback of such an arrangement is
that the unfinished carpet has to be brought to a foamer
so that the lamination can be done on a foaming line or,
alternatively, the carpet manufacturer has to invest in
foaming machinery for his factory.
Further, there is considerable stress c>n the
foam in use when it is directly attached to the carpet.
Without a covering to give the foam some dimensional
stability, the unsupparted foam can easily shear" tear
or delaminate from the carpet. r
In addition, it would be highly desirable in
many applications if a lower density foam could be used.
However, when this method of direct application of the
foam to a carpet primary layer is used, higher density
foam is normally needed to give the foam enough
stability.
Some carpet does have a backing such as an
"action backing" of polypropylene or jute over the back
of the carpet. Affixing the foam directly to such
backing could reduce the stress on the foam but attempts
to achieve this have caused delamination groblems
between the foam and the action backing.
Finally this application of foam directly to a
carpet primary layer "in-line" normally requires that
any covering or loop backing on the foam be placed there
while the foam is setting which can create additional
disadvantages.
CVO 94/00043 ~ . P~'lr~cA93~'oox~~
3
SAY C1F THE INVENTION
The present invention attempts to create an
improved carpet construction containing an interposed
layer of foam and a loop backing.
It has been discovered that this can be
achieved by manufacturing the foam layer with a fabric
covering on both sides of this layer (the bottom
covering having loops) and then subsequently affixing
this foam sandwich to a carpet backing using
conventional methods. The foam sandwich can b~e secured
to the carpet pile layer at the same time and with the
same material that binds and seals the carpet pile
layer, i.e. "in line" or the foam sandwich can be made,
stored and attached in a subsequent step to the carpet
which had previously been pre-coated with a binder.
This improvement can enable carpet containing
a loop backing to be manufactured with existing
machinery so that a pre-existing, earlier manufactured
foam layer can be attached by a binder or adhesive to
the back of a carpet by the use of currently available
conventional carpet machinery.
Further different thicknesses or gauges of
foam can be retained by a carpet manufacturer for later
attachment to different carpet pile layers, as required.
A fabric covering placed on both sides of a
pre-manufactured foam layer also can increase the
dimensional stability of the foam to allow lower density
foam to be used
and can also allow, in a preferred embodiment, the use
of foam not formed in-line, such as slab foam.
CA 02136210 2001-04-05
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Fabric is preferable to a chemical or
polymer covering because it can impart dimensional
stability to the foam while at the same time providing
some flexibility and protection to the foam from
ripping and breaking.
Further, in the preferred embodiment, the
upper surface fabric covering is a fabric which can
have a rough outer surface, such as a hairy or loopy
fabric, with upstanding threads, which will improve
adhesion to the carpet backing.
While the fabric covering can be placed on
the foam using conventional methods, it is desirable,
in the preferred embodiment, to place the covering on
the surface of the foam after the foam has formed.
This prevents infiltration of the foam into the fabric
covering, which is usually not desirable, particularly
with respect to the lower covering of the foam layer
which has the loops needed to attach the carpet to the
floor.
Thus the present invention in one aspect
consists of a laminated carpet for attachment to a
floor without a separate underpad comprising (i) a
primary layer having pile elements substantially
covering a first side of the primary layer, (ii) a
foam layer having a first fabric covering on an upper
surface of such layer and a second covering having
exposed loops on a lower surface of such layer, (iii)
means for securing the first and second covering to
the foam layer, and (iv) means for securing the upper
surface of the first covering of the foam layer to the
primary layer so that the pile elements and the loops
are exposed on opposite faces of the carpet.
CA 02136210 2001-04-05
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In another aspect the invention consists of
a carpet comprising a primary layer having pile
elements tufted into and through such layer and
substantially covering a first side of the primary
layer, a foam layer having a first fabric covering
exposing threads outstanding from the upper surface of
such layer and a second fabric covering exposing loops
on the lower surface of such layer, and adhesive means
for securing the first fabric covering of the foam
layer to the primary layer so that the outstanding
threads of the upper surface of the first covering and
the tufts extending through the primary layer are
sealed together, and so that the pile elements and the
loops of the lower surface of the foam layer are
exposed on opposite faces of the carpet lamination.
BRIEF DESCRIPTION OF THE DRAWINGS
Certain embodiments of the invention are
described with reference being made to the
accompanying drawings wherein:
FIG. 1 is a sectional elevation of a
preferred laminated carpet embodiment in
accordance with the present invention prior
to the installation of the foam layer onto
the carpet backing; and
FIG. 2 is a sectional elevation of this
preferred laminated carpet embodiment in
which the foam layer and carpet backing have
been attached together.
DETAILED DESCRIPTION OF THE INVENTION
Referring to the drawings, figure 1 shows a
conventional carpet backing 1 of polypropylene or other
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WU 94/00043 PC'f/CA93/0027s
conventional material forming a primary layer containing
yarn 3 needled through the backing to form tufted
bundles 5.
A foam layer 7 is shown. Such foam layer can
be made by any conventional means such as by chemically
blown, frothed ar pre-manufactured slab or any other
means that would produce the necessary resilience, shear
strength and tensile strength. In the preferred
embodiment, a loopy woven or non-woven fabric covering 9
and 11 is affixed to the foam, after the foam is made,
by using adhesives, flame lamination or ultrasound or
any other method which produces a satisfactory
peel-delamination strength without undue infiltration
into the loop fabric covering, thus maintaining a high
degree of flexibility.
However in some cases, it is possible, though
not usually preferable,,to place the covering on the
foam while the foam is being formed or setting up. In
this case, the benefits of gauge control and of
non-penetration of the covering will not be equal to a
carpet construction in which the foam has formed first,
but there will still be advantages derived from the
separate covering and manufacture of the foam as
previously described.
Placing the covering on the foam before the
foam has set has drawbacks in that the loop fabric is
sometimes infiltrated to a degree that is not preferable
and a board-like effect can be created as the foam
hardens around and in the loop fabric.
The infiltration, which can occur may also
destroy or impede all or some of the loops from
performing their function as was intended, due to loss
of directional movement. Further, this method of
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in-line lamination reduces the ability to lower the
weight of the loop fabric by opening the gauge. Opening
the gauge to reduce the weight of the loop fabric can
cause further penetration of liquid foam which could
cause "bleeding" of the liquid foam to the ather side of
the loop fabric thus eliminating the use of some or all
of the loops.
It is advantageous to have the loop layer
maintain its ability to stretch in length and width. A
more open gage and less penetration of the foam into the
loop layer can allow the loop layer to give. This can
allow completed carpet product with its attached
interposed foam pad to be rolled more easily and be more
flexible.
Additionally, the in-line method of depositing
foam while attaching it to the carpet yarn backing does
not produce the most efficient form of foam gauge
control. Since the in-line lamination requires the
manufacturing of the foam at the same time as its
attachment to the back of the carpet, it is difficult to
control the exact gauge or height of the foam during
this process.
Nevertheless the principal advantages of the
invention can be achieved by covering the foam on both
sides with fabric as described, and it may initially be
easier for some manufacturers, with their existing
machinery, to add this covering while the foam is
setting up notwithstanding the other disadvantages.
Preferably the loop fabric 11 is a locked loop
by which is meant that the loops are firmly set into the
loop backing either by the adhesive used to attach the
covering to the foam, the form of loopy material that is
used, or (in the non-preferred embodiment) by the
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WO 94/00043 ~'O'f/~CA~3/00275
_ g _
infiltration of the foam into the fabric. It has been
found that a knit is ideal, especially a warp or tricot
knit, for having the proper degree of locked loop in the
fabric. Such a warp or tricot knit is preferably used
for both loop layers, however a woven or other material
may also be used. The term "fabric" means any woven,
non-woven, pressed material of natural or artificial
fibres.
The loop layers 9 and 11 do not need to be of
the same material or strength. The loop layer 9 is less
critical and preferably has loops or upstanding threads
to assist adhesion to the backing 5. Many coverings
would be suitable if they have the desired strength,
flexibility and ability to adhere to the foam.
As previously stated, the upper loop covering
9 is preferably a knit or other "locked loop" material
but it could also be a fabric which has upstanding
threads rather than loops such as many needle punched
materials or felt or other kinds of loopy fabric in
which the loops are not firmly locked in place. It is
thought that the upstanding threacls fill in the carpet
primary layer and assist in adhesion of the foam layer
to the carpet primary layer. Normally the carpet will
have a "backing" of polypropylene but the invention
would work equally well with a carpet without a distinct
backing in which the warp and weft of the carpet forms
the primary'layer.
With the embodiment of figure 1 the foam
material can be transported and stored, after it is
covered on bath sides with a loopy fabric, in an easier
way than with uncovered foam. Uncovered foam rips,
tears and soils easily and is not as suitable for
handling, transportation and storage. In addition, the
loop covering on both sides of the foam gives the foam
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greatly increased sheer and tensile strength while
retaining and possibly even improving the foam's natural
resilience.
The preferred construction uses slab foam
because gauge or thickness control is easier with slab
foam than with other methods of foam manufacture.
Figure 2 shows the carpet with the foam
installed on a carpet backing. The foam can be
installed using conventional techniques by the u:ae of
any binder or adhesive 13. If a loopy fabric is used it
is preferable if the adhesive infiltrates and seals the
loop material 9 and the carpet tufts 5 together.
This adhesive can be applied using
conventional carpet machinery in either a one pass
system in which the binder being used does both the job
of encapsulation, tuft-bind and secondary backing
lamination of the pre-manufactured covered foam layer,
or in an end of line or post-laminate off-line system
whereby a conventional primary backing with yarn needled
through is backed using a light coat (e.g. "kiss-coat")
of adhesive binder to laminate the pre-manufactured slab
foam sandwich. The resulting product can have increased
dimensional stability, better tuft-bind and more
flexibility.
The~carpet can be manufactured as tiles or in
rolls for wall-to-wall installation. However, the
invention finds its greatest benefit in wall-to-wall
installation where the dimensional stability of long
runs of carpet and the difficulties of installation are
more significant problems.
