U.S. patent application number 10/956143 was filed with the patent office on 2005-02-24 for waste carpet as backing filler for floor coverings.
This patent application is currently assigned to Mohawk Brands, Inc.. Invention is credited to Bell, Michael E..
Application Number | 20050042413 10/956143 |
Document ID | / |
Family ID | 32961222 |
Filed Date | 2005-02-24 |
United States Patent
Application |
20050042413 |
Kind Code |
A1 |
Bell, Michael E. |
February 24, 2005 |
Waste carpet as backing filler for floor coverings
Abstract
The amount of waste carpeting that is landfilled or otherwise
disposed of is significantly reduced, as is the need for the mining
mineral fillers, by utilizing specially processed waste carpeting
as a filler in the production of new hot melt carpet backcoating,
roofing materials, or other similar products. Waste carpeting (post
consumer and/or waste from new carpet manufacture) is collected and
size reduced, typically in a first coarse size reduction, and then
after densification to a finer size reduction. The size reduced
waste carpeting is added as filler to at least one other material,
such as polymers in standard latex, EVA, or PVC carpet
backcoatings, to provide a hot melt composite used in the
manufacture of a useful product (like carpet backcoating), and then
the composite material is used to make the useful product (such as
carpet backcoating, which is used as a primary or secondary
backcoating in the manufacture of new carpeting). The waste
carpeting may provide between about 40 100% of the filler of carpet
backcoating, with any remainder made up by conventional fillers,
such as calcium carbonate.
Inventors: |
Bell, Michael E.;
(Lexington, VA) |
Correspondence
Address: |
NIXON & VANDERHYE, PC
1100 N GLEBE ROAD
8TH FLOOR
ARLINGTON
VA
22201-4714
US
|
Assignee: |
Mohawk Brands, Inc.
Wilmington
DE
|
Family ID: |
32961222 |
Appl. No.: |
10/956143 |
Filed: |
October 4, 2004 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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10956143 |
Oct 4, 2004 |
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10376298 |
Mar 3, 2003 |
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6814826 |
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Current U.S.
Class: |
428/95 |
Current CPC
Class: |
B29B 17/0412 20130101;
Y10T 156/1005 20150115; B32B 2471/00 20130101; D06N 7/0078
20130101; D06N 2205/106 20130101; D06N 7/0076 20130101; Y02P 70/649
20151101; Y02W 30/625 20150501; Y02P 70/62 20151101; B29L 2031/7322
20130101; B32B 5/022 20130101; B32B 27/12 20130101; B32B 5/024
20130101; B32B 2272/00 20130101; Y10T 428/23979 20150401; D06N
2205/18 20130101; B32B 27/20 20130101; Y02W 30/62 20150501; B29B
17/0042 20130101; Y02P 70/651 20151101; D06N 7/0071 20130101 |
Class at
Publication: |
428/095 |
International
Class: |
B32B 033/00 |
Claims
1-17. (Canceled)
18. Carpeting having a face, primary backing, primary backcoating,
and at least one secondary backcoating; and wherein at least one of
said primary and secondary backcoatings comprises a polymer and
filler, and wherein at least about 40% of said filler is
size-reduced waste carpeting, at least one of said primary
backcoating or secondary backcoating including a hot melt compound
applied as a molten mixture of polymers and fillers and cooled to
form said one backcoating.
19. Carpeting as recited in claim 18 wherein at least one of said
backcoatings comprises a molten mixture of about 5-18% EVA
copolymer, about 32-45% resin, about 20-50% size-reduced waste
carpeting filler, and about 0-30% calcium carbonate filler.
20. Carpeting as recited in claim 18 wherein said size-reduced
waste carpeting comprises size-reduced post-consumer waste
carpeting, and wherein said filler has a particle size and range of
about 200-325 mesh, nominally.
21. Carpeting as recited in claim 18 wherein said secondary
backcoating includes the hot melt compound of polymers and fillers
together with a fabric material laminated therewith and to the
primary backing.
22. Carpeting as recited in claim 18 wherein the size-reduced waste
carpeting includes latex backed waste carpeting.
23. Carpeting as recited in claim 22 including a fabric material
laminated with the one backcoating.
24. Carpeting as recited in claim 18 wherein the size-reduced waste
carpeting includes post-consumer waste carpeting.
25. Carpeting as recited in claim 18 wherein the size-reduced waste
carpeting includes post-industrial waste carpeting.
26. Carpeting as recited in claim 18 wherein the said secondary
backcoating includes the reduced latex backed waste carpeting, and
a fabric material laminated with the secondary backcoating
containing the size-reduced latex waste carpeting.
Description
BACKGROUND OF THE INVENTION
[0001] In the conventional manufacture of floor coverings, e.g.,
carpeting and carpet tiles, hereafter sometimes collectively called
carpeting, tufted pile yarns or like facings are held in place by a
primary backing, and typically a secondary backing, as well as
possibly other layers. At least some of the carpet backings
(particularly latex, EVA, PVC, or other polymer-based backings) use
filler as an important component thereof. The standard filler that
is used is a mineral filler, typically calcium carbonate, alone, or
in combination with some other common metal salts.
[0002] During the carpet manufacturing process there is waste
carpeting produced, which is typically landfilled or burned. When
new carpets are installed in place of old carpeting, the used,
waste, carpeting (which is post-consumer waste at that point) is
ripped up and also typically landfilled or burned. The calcium
carbonate, or like mineral fillers, that are used in carpet
backings are mined, and therefore have associated therewith the
conventional problems associated with the mining of materials.
BRIEF DESCRIPTION OF THE INVENTION
[0003] According to the present invention methods of recycling
waste carpeting and producing carpeting utilizing recycled
materials, are provided which substantially eliminate or
significantly reduce the problems discussed above. According to the
present invention instead of using calcium carbonate, which is
mined, as the filler for a carpet backing, recycled waste carpet
(from new carpet production and/or from post-consumer waste) is
used as the filler material in a hot melt application process in
which the molten material including these waste products are
applied to the carpet backing to deliver the desired physical
properties such as strength and dimensional stability. This
substantially eliminates, or at least significantly reduces, the
amount of landfilling or other waste disposal that is necessary for
waste carpeting while enabling the manufacture of fresh floor
coverings using the waste materials.
[0004] The invention is also applicable to the production of other
materials containing fillers, including various extruded
thermoplastic and thermoset materials that typically use calcium
carbonate filler, including, but not limited to, roofing materials,
road paving materials, awnings, and tarps.
[0005] In a preferred embodiment according to the present
invention, there is provided a method of manufacturing floor
coverings using waste carpeting as at least part of backing
material for the covering, comprising substantially sequentially
the steps of (a) collecting waste carpeting, (b) effecting size
reduction of the waste carpeting, (c) adding the size-reduced waste
carpeting as a filler to at least one other material to form a
molten mixture for backcoating a primary backing of the floor
covering, (d) applying the molten mixture and a fabric material to
a primary backing to form a laminate on the floor side of the
primary backing and (e) cooling the laminate on the primary backing
to form a floor covering having the backcoating containing the
waste carpeting on a floor side of the primary backing.
[0006] In the method step a) may be practiced to collect
substantially only post-consumer waste carpeting, substantially
only waste carpeting from new carpeting manufacture, or a blend of
both. Post-consumer waste carpeting can be cleaned by any
conventional cleaning technique before use, if desired or
necessary. While the method is typically practiced utilizing all of
the face yarn and primary backing, and backcoatings, under some
circumstances the method may further comprise, between a) and b),
separating the face yarn and primary backing from waste carpeting
backcoating to produce a substantially face yarn and primary
backing-free waste carpeting backcoating, and using substantially
only the waste carpeting backcoating in step b). Also, various
carpet backcoatings may be separated from each other so as to use
only one particular carpet backcoating, such as the primary or
secondary backcoating.
[0007] The invention may also further comprise, between steps b)
and c), step f) densifying the size reduced carpeting, and
effecting a further size-reducing thereof. Also step c) may be
practiced so as to provide between approximately 40-100% of the
filler of the carpet backcoating as size-reduced waste carpeting.
For example in one embodiment of the invention, steps c) and d) are
practiced to produce a carpet backcoating with about 5-18% EVA
copolymer, about 32-45% resin, about 20-50% size-reduced waste
carpeting filler, and about 0-30% calcium carbonate filler. Also in
the practice of the method, steps b) and f) may be practiced to
produce waste carpet coating have a particle size and range
substantially the same as calcium carbonate filler.
[0008] The method includes latex carpet backcoatings and is not
restricted to thermoplastic resin such as PVC carpet backcoatings,
EVA, or other polymer-based backcoatings.
[0009] The invention also further typically comprises making new
carpeting with the carpet backcoating.
[0010] Alternatively according to the present invention, steps c)
and d) may be practiced to produce extruded thermoplastic or
thermoset products and/or to produce awnings, roofing materials,
road paving materials, or tarps, with a particle size of the waste
carpeting filling between about 20-100 mesh.
[0011] According to another aspect of the present invention there
is provided carpeting having a face and primary backing, primary
backcoating, and at least one secondary backcoating; and at least
one of the primary and secondary backcoatings comprising a polymer
and filler, and wherein at least about 40% of the filler is
size-reduced waste carpeting, at least one of the primary
backcoating or secondary backcoating including a hot melt compound
applied as a molten mixture of polymers and fillers. At least one
of the backcoatings may comprise about 5-18% EVA copolymer, about
32-45% resin, about 20-50% size-reduced waste carpeting filler, and
about 0-30% calcium carbonate filler. The size-reduced waste
carpeting may comprise size-reduced post consumer waste carpeting,
and the filler may have a particle size and range substantially the
same as calcium carbonate filler.
[0012] It is the primary object of the present invention to produce
new materials including floor coverings utilizing recycle waste
carpeting to eliminate disposal problems, while at the same time
reducing the mining or other production of filler materials
typically used in carpet backing, or other products. These and
other objects of the invention will become clear from an inspection
of the detailed description of the invention and from the appended
claims.
BRIEF DESCRIPTION OF THE DRAWINGS
[0013] FIG. 1 is a schematic cross-sectional view of conventional
carpeting, or carpeting produced according to the present
invention; and
[0014] FIG. 2 is a block diagram illustrating various method steps
that may be practiced according to the present invention.
DETAILED DESCRIPTION OF THE INVENTION
[0015] A standard construction of carpeting is illustrated
schematically by reference numeral 10 in FIG. 1. The carpeting
includes face yarn 11, tufted into a woven or spun bonded fabric 14
known as a primary backing. The primary backing 14 has pile yarns
11 tufted therethrough extending outwardly from one face, a primary
backcoating or precoat 12 on the opposite face, and at least one
secondary backcoating or main coat 13. Other layers may also be
associated with the carpeting 10. The primary backcoating or
precoat 12 typically comprises latex, PVC, EVA, or other
polymer-based material, and the secondary backcoating 13 may also
comprise or include polymers in conjunction with a secondary
backing material 15 such as a fabric woven from polypropylene
yarns. Typically one or both of the primary backcoatings 12 and
secondary backcoating(s) 13 include filler. The most common filler
is mineral filler, typically calcium carbonate, although other
fillers may be utilized, or calcium carbonate can be used with
other common metal salts. According to the invention, new carpeting
10 may be produced with the filler of one or both of the primary
backcoating 12 and secondary backcoating(s) 13 as size-reduced
waste carpeting instead of calcium carbonate as all or part of the
filler.
[0016] The carpeting 10 may also have any number of other layers,
depending upon use. For example the carpeting 10 may have a
conventional secondary backing (typically a woven or needle-punched
fabric adapted to contact the floor or padding). Thus, the primary
backcoating 12 may include a filler of size-reduced waste carpeting
with one or more secondary backcoating 13 layers including or not
filler of size-reduced waste carpeting. Preferably, however, the
secondary backcoating 13 includes the filler of size-reduced waste
carpeting in conjunction with a fabric material laminated to the
primary backcoating 12.
[0017] FIG. 2 schematically illustrates an exemplary process
according to the present invention. In the process, firstly used
carpeting is initially collected as indicated at 20 in FIG. 2. The
collection may comprise post-consumer waste carpeting collection,
collection of waste carpeting from the standard procedures
associated with the manufacture of new carpeting, or both. If the
used carpeting collected at 20 is contaminated in any significant
manner it may be cleaned using any suitable conventional technique
(either before or after size-reduction as hereinafter
described).
[0018] It is contemplated that according to the present invention
the waste carpeting that is subsequently employed in the
manufacture of new carpeting utilizes substantially all components
of waste carpeting, including the face yarns, primary backing, and
primary and secondary backcoatings, and perhaps other components.
However under some circumstances for either part or all of the
waste carpeting it may be desirable to separate the face and
primary backing and backcoatings from each other before further
procedures. The optional separation of the carpet components is
illustrated schematically at 21 in FIG. 2. The separation may be
accomplished, depending upon whether the face and all backings and
backcoatings are to be separated, utilizing any suitable
conventional technique, such as generally described in U.S. Pat.
No. 5,728,741 (the disclosure of which is hereby incorporated by
reference herein). If only a certain backing or backcoating is
used, an attempt may be made to match it with the manufacture of
new backing or backcoating of substantially the same type (e.g.
latex backcoating).
[0019] Whether or not procedure 21 is utilized, the waste carpeting
is subjected to size-reduction. As illustrated at 22 in FIG. 2, the
size reduction preferably comprises a first coarse size-reduction,
which may be accomplished utilizing any suitable conventional
chopping equipment, such as disclosed in U.S. Pat. Nos. 5,728,741
and 5,814,673.
[0020] While under some circumstances only the size-reduction 22
may be utilized, oftentimes it is necessary or desirable to effect
densification and further size-reduction of the waste carpeting.
Densification, as illustrated at 23 in FIG. 2, comprises increasing
the density or specific gravity of the size-reduced waste carpeting
from 22, to make it easier to handle the material during further
processing. The size-reduced particles from 22 in FIG. 2 may be too
large and fluffy to be handled easily, and may not blend
sufficiently during subsequent processing. Therefore densification
at 23 is desired. Densification at 23 may be practiced utilizing
any suitable conventional technique, such as condux densification
or use of a granulator, as described in U.S. Pat. No.
5,728,741.
[0021] Preferably after densification at 23, there is a second,
finer, size-reduction of the waste carpeting, as indicated at 24 in
FIG. 2. In many circumstances the second size-reduction at 24 is
practiced so as to produce waste carpeting having a particle size
and range that is substantially the same as calcium carbonate
filler, e.g. in the range of about 200-325 mesh, nominally. The
second size reduction at 24 may be practiced using techniques that
are conventional per se, such as pulverizing or acting upon with
roller mills.
[0022] In the preferred procedure according to the present
invention, the size-reduced waste carpeting from 20 through 24 is
used as a filler with other standard carpet backcoating components,
either for primary backcoating, or a secondary backcoating, or
other backing elements of carpeting (typically collectively
referred to as main coats). For example latex, EVA, or PVC
backcoatings of conventional construction are particularly suitable
for utilization of the waste carpeting filler from 20 through 24 in
FIG. 2. The waste carpeting can be used as substantially the only
filler, or can replace a significant amount of the filler that is
utilized.
[0023] While a wide variety of polymers or other materials may be
used to produce the carpet backcoatings according to the present
invention, one exemplary carpet backcoating will be described
below. A standard hot melt backcoating such as the Lees Unibond.TM.
backcoating system may contain, for example [all percentages given
herein are by weight unless other indicated]:
[0024] a. 5-18% EVA copolymer
[0025] b. 32-45% resin, such as ECR-171 from Exxon
[0026] c. 50% calcium carbonate filler, JR-78.
[0027] According to the invention, instead of using all calcium
carbonate as the filler, a significant amount of the calcium
carbonate usually added to the molten resin and copolymer can be
replaced by the size-reduced waste carpeting according to
procedures 20 through 24 of FIG. 2. For example, between about
40-100% of the filler of the carpet backcoating (e.g., precoat 12
or secondary backcoating 13) may be size-reduced waste carpeting.
In the above example, then, about 20-50% of the carpet backcoating
may be size-reduced waste carpeting filler, and about 0-30% calcium
carbonate filler, e.g. about 25% each of size-reduced waste
carpeting (about 200-325 mesh, nominally) and calcium carbonate as
fillers.
[0028] The waste carpeting filler according to the present
invention is mixed with the other component(s) using standard hot
melt mixing equipment and techniques as indicated at 25. In a
preferred embodiment as indicated in FIG. 2 at 26, the hot molten
mixture of polymer, resin and size-reduced waste carpet is applied
to the primary backing or backcoating. A secondary backing
material, such as a woven, felt or needle-punched fabric material,
is also applied to the hot molten mixture, as indicated at 27,
which, together with the application of molten mixture indicated at
26 containing the waste carpeting filler, form a laminate on the
floor side of the primary backing. The molten mixture is applied to
the backside of the primary backing in hot melt form by applicator
rolls to form with the fabric material one or the other or both of
the backcoatings on the floor side of the primary backing as
indicated at 27. The backcoating is then cooled, as indicated at 28
in FIG. 2, again using conventional techniques. Additional
backcoating from 26 may be applied to make the new carpet, again by
conventional techniques. The backing from 27 may be used as the
primary backcoating (12); or a secondary backcoating (13) of the
carpeting with or without but preferably with the fabric material;
or as a filler in all of the backcoatings. It will be appreciated
that the latex-backed waste carpet may also be used in the
foregoing process in lieu of thermoplastic or thermoset
materials.
[0029] While the preferred embodiment of the invention is the
utilization of waste carpeting in new carpet manufacture, other
uses are also possible. For example as illustrated schematically at
30 in FIG. 2, size-reduced waste carpeting from 20-24 may be added
as a filler to other materials to make other useful products, such
as extruded thermoplastic and thermoset materials that typically
use calcium carbonate or other mineral fillers. Again the waste
carpeting used at 30 may be substituted for part or substantially
all of the calcium carbonate conventional filler. A number of other
products that may be made comprise almost all products that
typically can use calcium carbonate (or its equivalents) as the
filler, and some of the new products that can be made--as
illustrated schematically at 31 in FIG. 2--include roofing
materials, awnings, road surfacing materials, and tarps, all of
which contain mineral fillers. For these applications, particle
size may not need to be as small as for carpet backcoatings, e.g.
between about 20-100 mesh.
[0030] During any of the procedures described above various
conventional refinements may be employed. For example screening or
other contaminant removal may be practiced where desired, as can be
testing, sampling, or any other suitable techniques that are
necessary or desirable in order to produce a product with desired
properties.
[0031] It will thus be seen that by practicing the present
invention it is possible to substantially eliminate or
significantly reduce landfilling or other disposal of waste
carpeting, and at the same time to reduce the mining of mineral
fillers, without sacrificing new product quality, by using
processed waste carpeting as a filler for new carpet backcoatings,
roofing materials, or in other situations.
[0032] While the invention has been described in connection with
what is presently considered to be the most practical and preferred
embodiment, it is to be understood that the invention is not to be
limited to the disclosed embodiment, but on the contrary, is
intended to cover various modifications and equivalent arrangements
included within the spirit and scope of the appended claims.
* * * * *