Note: Descriptions are shown in the official language in which they were submitted.
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BACKGROUND OF THE INVENTION
This invention relates to recyclable carpet and a
method of making recyclable carpet.
In the past, carpet has not been recyclable in the
sense that trimmed pieces of carpet, or used or wasted
carpet, could not be melted together and the resulting
material used to form new carpet. In ~he past, carpet has
been made with typically three or four main components.
These were the pile, the primary backing, the binder and in
some cases a secondary backing. These components each
served a separate and distinct purpose or function.
; ~ Therefore, materials for these components were chosen to
best provide the characteristics for fulfilling that
particular function or purpose. Because the functions and
purposes of the various components are different, the
materials of the various components have always been
different, such as nylon for one function and polypropylene
for a second and jute for a third. In some situations, two
of the components were sometimes made from the same
material. However, all of the three or four components were
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never made from the same material.
Because the various materials had different
characteristics in order to better provide the desired
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results, the various materials could not be softened
together to form a suitable single material that could be
suitably used to make new carpet, or suitably used for some
other purpose. Therefore, scrap cuttings from past carpet,
and even used carpet, could not be satisfactorily recycled.
Also, the binders that were used in past carpets,
often included components, such as glues or solvents, that
may possibly be considered hazardous or harmful to the
health of some people. Also, many binders included
materials or were made form materials that are not
recyclable, such as latex.
Also, some people are sensitive to some materials
that were used in past carpet. One such material was jute.
SUMMARY OF THE INV~NTION
Accordingly, it is an object of this invention to
at least partially overcome the dlsadvantages of the past
carpets. Alsol it is an object of this invention to provide
an alternative type of carpet that is recyclable in the
sense that the carpet, or pieces of the carpet, can be
melted and the resulting material can be reused to make
other carpet or be used for other purposes.
Accordingly, in one of its broad aspects, this
invention resides in providing recyclable carpet comprising
primary backing having first and second surfaces, and
wherein the backing is made from a first material having a
soEtening point wlthin a range from about 118 ~C to about
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270 C and having an ability to adhere to itself and
materials of substantially the same generic class when
softened and cooled; pile extending from at least the first
surface of the primary backing and made from a material that
is of substantially the same generic class as the first
material; and binder adhering to at least the second
surface of the primary backing and made from a material that
is of substantially the same generic class as the -Eirst
material.
Further aspects of the invention reside in
providing a method of manufacturing recyclable carpet,
comprising connecting to a primary backing having first and
second surfaces, and wherein the backing is made from a
first material having a softening point within a range from
about 118 C to about 270 C and having an ability to adhere
to itself and materials of substantilly the same generic
class when softened and cooled, a pile extending from at
least the first surface of the primary backing and wherein
the pile is made from a material that is of substantially
the same generic class as the first material; bringing
suitably softened binder made from a material that is of
: substantially the same generic class as the first material
into contact with at least the second surface of the primary
backing; softening a surface portion of the primary
backing; and cooling the binder and the primary backing so
as to allow the binder t~ adhere to the primary backing.
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Further aspects of the invention will become
apparent upon reading the following detailed desciption and
the drawings which illustrate the invention and preferred
embodiments of the invention.
BRIEF DESCRIPTION OF THE DRAWINGS
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In the drawinys:
Figure 1 is a schematic cross-sectional drawing of
a carpet of the invention.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
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OF THE INVENTION
As shown in Figure 1, recyclable carpet 10
according to the invention includes primary backing 12r pile
14 and a binder 16.
The primary backing 12 may be in a form that is
commonly used, in that the primary backing 12 may be woven
or non-woven, and it may be a film or a sheet. Preferrably,
the primary backing 12 is made from a material that is a
polyolefin, a polyamide or a polyester. ~owever, the
important characteristics of the the primary backing 12 are
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20 that it~be made from a material that has a softening point
within the range of about 118 C to about 270 C degrees,
and that the material has the ability to adhere to itself,
and other materials of the same generic class, when softened
~- and cooled. The phrase substantially the same generic
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class" is intended to mean and include those materials that
have substantially the same characteristics so as to permit
the two materials to be softened together and then, ~hen
cooled, to form one material.
When the material is softened, in addition to
being softened by heat, it is intended that !'softened~ may
also mean and includes being treated chemically or otherwise
so as to put the material into a condition which allo~s the
material to adhere to itself or other materials of the same
generic class.
S~itable materials will most likely be synthetic
materials. Preferrably, the primary backing 12 is be made
~ from polyethylene or butylene, and most preferrably from
- polypropylene. Also, the primary backing 12 could be made
from a nylon (a polyamide) such as nylon 6, nylon 6,6 or
nylon 12,12. Also, the primary backing 12 could be made
from a polyester.
A more detailed description of the type of
material that is a suitable material and the reasons for
select:ing that type of material is given later in this
disclosure after a fuller description of the overall carpet
10 is given.
The primary backing 12 has a first surface 12a and
~- a second surface 12b. Extending from at least the first
surface 12a of the primary backing 12 is pile 140 The pile
14 may also extend to a lesser extent from the second
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surface 12b of the primary backing 12. The pile 14 may be
in a form that is common such as i~ filament form or in spun
form.
The pile 14 is made from a material that is of
substantially the same generic class as the material from
which the primary backing 12 is made. It is expected that
the primary backing 12 will be made from a material that
includes some additives that give the material
characteristics that make the material better suited for its
particular purpose. However, it is contemplated that the
amounts and quantities of those additives would not
substantially affect the abilities of the materials to be
softened and then formed together into one acceptable
material.
Many of the additives that are added to the
materials are trade secrets of the particular material
manufacturer. For example, the manufacturer of the primary
backing 12 may add certain ingredients to give colour,
abrasion resistance, U~ light stability or flammability.
Similarily, the manufacturer of the primary backing 12 would
also add certain secret ingredients to give the primary
backing 12 preferred characteristics. Thus, it is not
possible to list all of the possible ingedients that could
be added to the various materials and not substantially
affect the characteristics of the materials for the purpose
of this invention. In any case, it is intended that a
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material that includes additives is included within the
meaning of a material of substantially the same generic
class if those materials have substantially the same
characteristics so as to permit the two materials to be
S softened and then, when cooled, to form one material~
The binder 16 adheres to at least the second
surface 12b of the primary backing 12. The binder 16 may
also adhere to the first surface 12a of the primary backing
12 and/or the pile 14.
The binder 16 is made from a material that is of
substantially the same generic class as the material from
which the primary backing 12 is made. However, once again,
it is contemplated that the material from which the binder
16 is made will include certain additives that are kept
secret by the manufacturers of binders. Provided that the
material allows the binder 16 to perform in accordance with
the requirements of the invention, it will be an acceptable
material.
he requirements of the invention are that the
~ 20 material of the pile 14 will adhere to the material of the
; primary backing 12 when the two are softened and cooled;
and that the material of the binder 16 will adhere to the
material of the primary backing 12 when the two are softened
and cooled.
~referrably, the material of the primary backing
12 is a polyolefin, p~rticularily polyethylene or butylene,
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and most preferably polypropylene.
Preferably, if the primary backing 12 is made from
polypropylene, the pile 14 and the binder 16 are made from
polypropylene also. As discussed above, even though all
three of the primary backing 12, pile 14 and binder 16 are
made from polypropylene, there may be, and most likely will
be, different additives in each of the parts. However,
provided the materials of each of the primary backing 12,
pile 14 and binder 16 is of substantially the same generic
10 class as the material of the others so as to allow the
materials to adhere when softened and cooled to the
respective component, the carpet 10 will fall within the
scope of the invention.
The binder 16 may also be made from a polyamide or
15 a polyester. Preferrably, when the primary backing 12 is
; made from a polyolefin, the pile 14 and the binder 16 are
also made from a polyolefin. Similarily, when the primary
backing 12 is made from a polyamide, the pile 14 and the
binder 16 are made from polyamides. Similarily, when the
20 primary backing 12 is made from a polyester, the pile 14 and
the binder 16 are made from polyesters.
Another aspect of the invention is a method of
manufacturing carpet, particularily recyclable carpet, such
as the carpet 10 as described above.
The method includes connecting to a primary
backing, preEerably a primary Dack1ng 12 as deRcribed above,
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a pile, preferably a pile 14 as described above. The pile
14 extends from at least the first surface l~a of the
primary backing 12 and is made from a material that is of
substantially the same generic class as the material o~ the
5 primary backing 12. The pile 14 may be connected to the
primary backing 12 in known manners such as by tufting,
needling or fusing, or otherwise.
The next step in the method is to bring suitably
softened binder into contact with at least the second
10 surface 12b of the primary backing 12. Preferably, the
binder is made from a material that is of substantially the
same generic class as the material of the primary backing
12. Preferably, the binder is a binder 16 as described
above.
Because the binder 16 is softened, it will cause a
softening of the material with which it comes in contact~
For example, if the softened binder 16 comes in contact with
the primary backing 12, the primary backing 12 will become
~ softened, either through the direct transfer of heat or
i 20 through the transfer of softening chemical. The amount of
softening of the material which comes into contact with the
already softened material depends on many factors. For
example, if the binder 16 comes in contact with the primary
backing 12, the extent of softening of the primary backing
12 will depend on the temperature of the binder 16 or the
amount and type of softening chemical apile 141ied to the
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binder 16, and the amount of time the binder 16 remains in
its softened state. Thus, the cooling rate of the binder 16
will also be a factor. The suitable selection of the
parameters of the vacious factors is well within the scope
of persons skilled in the art, particularily with some
experimentation with the various combinations of materials
and the various factors.
Thus, when the suitably softened binder 16 is
brought into contact with the primary backing 12, a portion
of the surface of the primary backing 12 will become
softened. The depth or penetration or extent of the
softening of the second material will depend on the
appropriate factors as generally discussed above. The
critical feature of the selection of materials and factors
is that the primary backing 12 cannot be softened to such an
extent that it completely melts or loses its ability to
function as either a primary backing, pile or binder as
appropriate. Qn the other hand, the primary backing 12, or
other appropriate material, must be softened sufficiently so
as to allow the binder 16 to adhere to the primary backing
12 when the binder 16 and the primary backing 12 are
cooled. Thus, throughout this disclosure and throughout the
claims, when the phrases "suitably softened" or "softened"
are used, it is intended that the phrase refers to and
includes all materials that are sof~ened, either directly by
heat or chemically, whlch will not result in the various
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materials meltin~ or losing their ability to function
properly and at the same time will allow the material to
adhere to another.
In a preferred embodiment of the invention, there
is an additional step in the method of making the carpet
10. The additional step involves suitably softening and
cooling the pile 14 and thereby adhering the pile 14 to the
primary backing 12 or binder 16, or both. Preferably, the
pile 14 is softened by bringing the pile 14 into contact
with the softened binder 16 or the softened primary backing
12. Thus, preferably, the pile 14 would be softened at
approximately the same time as the suitably softened binder
16 makes contact with the primary backing 12. In this
embodiment, some of the suitably softened binder 16 will
15 come into contact with the pile 14 and soften the pile 14.
When the pile 14 is cooled, it will be adhered to either the
binder 16 or primary backing 12, or both.
In a further embodiment of the invention, a
primary backing, preferably a primary backing 12 as
20 described above, is provided in a suitably softened state.
Pile, preferably pile 14 as described above and made from a
material that is of substan~ially the same generic class, is
brought into contact with the suitably softened primary
backing 12. Thus, a surface portion of the pile 14 is
25 softened. The pile 14 and the primary backing 12 are then
cooled so as to allow the pile 14 to adhere to the primary
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backing 12.
Also, suitably softened binder, preferably binder
16 as described above and made from a material that is of
substantially the same generic class, is brought into
; 5 contact with at least the second surface 12b of the the
primary backing 12. The binder 16 and the primary backing
12 are then cooled so as to allow the binder 16 and the
primary backing 12 to adhere to each other.
Preferably, there is an additional step to the
method whereby the binder 16 softens a surface portion of
the pile 14, and the binder 16 and the pile 14 are cooled so
as to allow the binder 16 to adhere to the pile 14.
Preferably, the step of bringing the pile 14 into
~ contact with the softened primary backing 12 takes place at
: 15 about the same time as the step of bringing the softened
binder 16 into contact with the primary backing 12.
Another aspect of the invention resides in
:~ providing a method of manufacturing carpet, particularily
recyclable carpet, comprising attaching the binder,
-~ 20 preferably a binder 16 as described above, to at least the
second surface 12b of a primary backing, preferably a
primary backing 12 as described above, and then attaching
pile, preferably a pile 14 as described above, to at least
the first surface of the primary backing 12.
~: 25 Preferably, in this method, the primary backing 12
and the binder 16 are softened, cooled and adhered together
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in a manner similiar to those disclosed above. However, the
primary backing 12 and the binder 16 may be attached by
other suitable means.
After the primary backing 12 has been adhered to
the binder 16, this primary backing/binder combination can
be transported to another area of the same mill or to
another mill to have the pile 14 attached. It is also
possible to have the pile 14 attached simulataneously or
almost simultaneously with the step of adhering the
binder 16 to the primary backing 12.
If the primary backing/binder combination is
cooled before the pile 14 is be attached, the pile 14 may be
attached by methods such as needling, tufting, fusing or
otherwise. Preferably, the pile 14 is attached to at least
the first surface of the primary backing 12 by softening,
cooling and adhering the pile 14 to the primary
backing 12. In this situation, it may be necessary to
resoften at least the first surface 12a of the primary
backing 12.
The above teachings respecting other methods of
; manufacturing carpet, particularily recyclable carpet lO,
are also applicable to this aspect o the invention.
It will be understood that, although various
features of the invention have been described with respect
to one or another of the embodiments of the invention, the
various features and embodiments of the invention may be
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combined or used in conjunction with other features and
embodi.ments o~ the i.nvention as described and illustrated
herein.
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 these particular embodiments. Rather~ the invention
includes all embodiments which are functional, chemical or
mechanical equivalents of the specific embodiments and
features that have been described and illustrated herein.
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