Patent Grant
6863090
The present invention involves woven carpet backings and a method of manufacturing and using such backings.
Conventional carpets are generally constructed by inserting a piling yarn through a primary backing fabric (also referred to herein as “primary carpet backing” or “primary backing”) to form tufts of yarn which project from the surface of the fabric. The piling yarn may be inserted through the use of a tufting needle, which penetrates the primary carpet backing. The primary backing is then coated with an adhesive to secure the yarn to the primary backing, and to allow a secondary carpet backing (or “secondary backing”) to be affixed to the primary backing. A primary backing may be made of a woven fabric, or may be made of a non-woven fabric.
One type of conventional primary carpet backing may comprise a woven fabric, made of warp yarns and fill yarns using a traditional weave, such as a plain weave. The term “fill yarn” may also be known as a “weft yarn” or “woof yarn.” Woven carpet backings are easier to process through tufting than non-woven carpet backings, and have the ability to “heal” from tufting penetrations. The term “heal” refers to the hole caused by a tufting needle closing once the needle is removed from the backing.
Another conventional primary carpet backing comprises a non-woven fabric. A non-woven fabric is usually defined as an assembly of textile fibers joined by mechanical interlocking in a random web or mat. Fibers may also be joined by fusing (in the case of thermoplastic fibers) or by bonding with a cementing medium, such as starch, glue, casein, rubber, latex, a cellulose derivative, or a synthetic resin. Non-woven fabrics generally have greater dimensional stability than woven fabrics.
Conventional carpet may suffer from a drawback, e.g., requiring both a primary carpet backing and a secondary carpet backing. This construction requires two backings to manufacture the carpet, thereby increasing materials, costs, and time for constructing a carpet.
An object of the invention is to overcome this and other drawbacks in existing carpets.
Another object of the invention is to provide a woven carpet backing (“carpet backing” or “backing”) comprising monofilament warp yarns and alternating monofilament and multifilament fill yarns.
Another object of the invention is to provide a woven carpet backing with the look of a primary carpet backing on one side of the woven carpet backing and the look of a secondary carpet backing on the other side of the woven carpet backing.
Another object of the invention is to provide a carpet with similar dimensional stability to conventional carpeting without requiring the use of a secondary carpet backing.
Another object of the invention is to provide a woven carpet backing where substantially all of the multifilament fill yarns are placed on one side of the woven carpet backing and substantially all of the monofilament fill yarns are placed on the other side of the carpet backing.
Another object of the invention is to provide a woven carpet backing where the fill yarn coverage factor is large enough to cause adjacent fill yarns to physically contact at least a portion of each other.
Another object of the invention is to provide a carpet using the woven carpet backing of the present invention.
These and other objects of the invention are accomplished according to various embodiments of the invention. One embodiment of the invention provides a woven carpet backing. The woven carpet backing comprises monofilament warp yarns and alternating multifilament and monofilament fill yarns. The woven carpet backing is woven using a weave, preferably a non-traditional weave, that places substantially all of the multifilament fill yarns on one side of the carpet backing and substantially all of the monofilament fill yarns on the other side of the carpet backing. In one embodiment, substantially all of the multifilament fill yarns are placed on the face of the carpet backing and substantially all of the monofilament fill yarns are placed on the back of the carpet backing. The carpet backing may be overstuffed such that the monofilament fill yarn coverage factor, and/or the fill yarn coverage factor are greater than one hundred percent.
Another embodiment of the invention provides a method of using a floor covering comprising tufted pile yarns inserted into a woven carpet backing. The method comprises forming a woven carpet backing comprising monofilament warp yarns and alternating monofilament and multifilament fill yarns. The woven carpet backing includes substantially all of the monofilament fill yarns on one side of the woven carpet backing and substantially all of the multifilament fill yarns on the other side of the woven carpet backing. Subsequently, carpet yarns are tufted through the carpet backing to form the floor covering, which is placed on an area of the floor. Preferably, an adhesive agent, such as a conventional latex mixture or cementing medium, such as starch, glue, casein, rubber, latex, a cellulose derivative, or a synthetic resin, or any adhesive conventionally used in floor coverings is then applied to the face of the carpet backing. The adhesive agent is believed to improve carpet stability and improve tuft bind, i.e., locks in carpet yarns. The woven carpet backing may be overstuffed such that the monofilament fill yarn coverage factor, and/or the fill yarn coverage factor are greater than one hundred percent.
Thus, the floor covering comprises a single carpet backing having carpet yarns tufted into it. This eliminates the need for a primary carpet backing and a secondary carpet backing considered necessary in conventional carpets.
Another embodiment of the invention provides a process for making a woven carpet backing comprising weaving a woven carpet backing comprising monofilament warp yarns and monofilament and multifilament fill yarns. The woven carpet backing includes substantially all of the monofilament fill yarns on one side of the woven carpet backing and substantially all of the multifilament fill yarns on the other side of the woven carpet backing. The woven carpet backing may be overstuffed such that the monofilament fill yarn coverage factor, and/or the fill yarn coverage factor are greater than one hundred percent.
Yet another embodiment of the invention is directed to a floor covering, such as a carpet, which includes:
(i) a woven carpet backing including warp and fill yarns, wherein the warp yarns comprise monofilament yarns and the fill yarns comprise alternating monofilament and multifilament yarns;
(ii) carpet fibers tufted into the woven carpet backing so that a top portion of the fibers protrudes from a back of the woven carpet backing and, preferably
(iii) a layer of an adhesive agent on a face of the woven carpet backing.
The woven carpet backing of the floor covering may be woven such that substantially all of the monofilament fill yarns are placed on one side of the woven carpet backing and substantially all of the multifilaments fill yarns are placed on the other side of the woven carpet backing. The woven carpet backing may be overstuffed such that the monofilament fill yarn coverage factor, and/or the fill yarn coverage factor are greater than one hundred percent.
Still another embodiment of the invention provides a woven carpet backing comprising a warp and a fill including two yarn types. Either the warp or the fill includes the two yarn types in an alternating fashion. The other of the warp and the fill uses only one of the two yarn types. The woven carpet backing is woven so that substantially all of one of the two alternating yarn types are located on the face of the woven carpet backing, and substantially all of the other of the two alternating yarn types are located on the back of the woven carpet backing. The woven carpet backing may be used in connection with a carpet, where carpet yarns are tufted through the woven carpet backing, and an adhesive agent is applied to the front of the woven carpet backing to secure the carpet yarns. A carpet comprising the woven carpet backing of this embodiment may further be used as a floor covering.
These and other objects of the present invention shall become apparent from the accompanying drawings and detailed description of the invention which follows.
a-4f illustrate examples bulk continuous fiber which may be used in an embodiment of the invention.
a, and 5b are illustrations of cross-sections of a woven carpet backing of
a and 6b are illustrations of cross-sections of a woven carpet backing of
a-7d are illustrations of cross-sections of a woven carpet backing of
The woven carpet backing of the present invention may be used as the only backing in a carpet or floor covering. Nonetheless, the woven carpet backing of this invention can be used with other floor covering components, e.g., with conventional secondary or primary carpet backings.
The woven carpet backing of the invention is used to provide a finished floor covering (e.g., a carpet) with similar dimensional stability compared with a conventional carpet which uses a primary backing and a secondary backing. To make a finished floor covering, the woven carpet backing is tufted with pile yarns in a conventional manner to form a tufted carpet, and an adhesive agent, such as a latex mixture, cementing medium, such as starch, glue, casein, rubber, latex, a cellulose derivative or a synthetic resin, or an adhesive, such as any adhesive conventionally used in floor coverings, is applied to the front of the woven carpet backing having the tufted pile yarns. No separate secondary backing is required. Nonetheless, a secondary backing may be attached to the front of the woven carpet backing having the adhesive agent applied to it.
According to an embodiment of the invention, the woven carpet backing may be woven using any weave, preferably a non-traditional weave, to provide the carpet backing of this invention.
According to one broader embodiment of the invention, a woven carpet backing including a warp and a fill may include two yarn types. Either the warp or the fill may include the two yarn types in an alternating fashion. The other of the warp and the fill uses only one of the two yarn types. The woven carpet backing is woven so that substantially all of one of the two alternating yarn types is located on the face of the woven carpet backing, and substantially all of the other of the two alternating yarn types is located on the back of the woven carpet backing.
In any embodiment of the invention, these yarns are woven using any weave which produces the carpet backing of the invention, preferably a non-traditional weave with a typical construction of about 10 to about 40 ends (i.e. yarns) per inch, preferably about 20 to about 30 ends per inch, more preferably about 22 to about 26 ends per inch, and most preferably about 24 ends per inch (warp yarns), and about 10 to about 50 picks (i.e. yarns) per inch, preferably about 20 to about 40 picks per inch, more preferably about 21 to about 30 picks per inch and most preferably about 22 picks per inch (fill yarns). In one embodiment of the invention, warp yarns of the woven carpet backing may range in size from about 100 to about 900 denier, preferably about 250 to about 750 denier, more preferably about 350 denier to about 600 denier, and still more preferably about 475 denier. Fill yarns may range in size from about 250 to about 2000 denier, preferably about 500 to about 1500 denier, more preferably about 750 denier to about 1250 denier, and still more preferably about 1050 denier for monofilament yarns and about 250 to about 3000 denier, preferably about 500 to about 2500 denier, more preferably about 1000 denier to about 2000 denier, and still more preferably about 1700 denier for multifilament yarns.
The monofilament and multifilament yarns may be made of synthetic fibers, such as polypropylene, nylon, polyester, or polyethylene. In one embodiment, the monofilament warp yarns are made of polypropylene, and monofilament fill yarns are made of polypropylene. The monofilament warp yarns may be made of the same or different material than the monofilament fill yarns. According to an embodiment of the invention, multifilament yarns may be spun yarn, ring spun yarn, open end spun yarn, continuous filament yarn or other types of multifilament yarn. The monofilament yarns may be single, untwisted filaments, tape yarn, or other types of monofilament yarn. The monofilament warp yarns may have the same or a different structure than the monofilament fill yarns.
According to a preferred embodiment of the invention, the woven carpet backing comprises a warp and a fill. The warp consists of monofilament tape yarns and the fill consists of alternating monofilament tape yarns and multifilament open end spun fibers. The woven carpet backing is woven with a construction consisting of about 22 picks per inch, and about 24 ends per inch.
According to an embodiment of the invention, multifilament yarns may be bulk continuous filaments, wherein the filaments have a body.
According to an embodiment of the invention, the monofilament and multifilament yarns in the woven carpet backing may have similar characteristics, such as similar shrinkage characteristics. An adhesive may be applied to the woven carpet backing for installation of the carpet, or for attaching another backing to the woven carpet backing. Applying the adhesive exposes the woven carpet backing to heat, and may result in shrinking and curling of the yarns in the woven carpet backing. Further, the woven carpet backing is often exposed to heat during the dying process for the carpet. Again, this heat may result in shrinking and curling of the yarns used. To minimize the shrinking and curling that may occur when the woven carpet backing is exposed to heat, the yarns used in the woven carpet backing may be heat-set (e.g. applying heat to the yarns to set the shrinkage characteristics). Heat-setting is the process of using either moist or dry heat to confer dimensional stability and other desirable properties to manufactured fibers, yarns, and fabrics. These other properties include wrinkle resistance and improved heat resistance.
According to an embodiment of the invention, both the monofilament yarns and the multifilament yarns may be pre-shrunk by heat-setting before being used in the woven carpet backing. By way of example, as the yarn is formed, it is heat-set by applying heat to the yarn to induce shrinkage. The yarn may then be woven to form a woven carpet backing with reduced shrinking and curling properties. According to an embodiment of the invention, the yarns may be used to make the woven carpet backing and then pre-shrunk by heat-setting (e g., applying heat to the woven carpet backing). Heat-setting yarns individually and heat-setting a woven carpet backing may be performed in any conventional manner known to those of ordinary skill in the art. The yarns used in the present invention may be heat-set to meet certain shrinkage requirements. Regardless of whether the yarns are heat-set individually (before they are woven into a carpet) or a woven carpet backing is heat-set, it is preferred that the extent of heat-setting is such that the shrinkage properties of the heat-set monofilament yarn are substantially similar to those of the heat-set multifilament yarn. Thus, by way of example, the heat-set monofilament yarn used in the woven carpet backing of the present invention may only shrink between zero percent (0%) and two percent (2%) after it has been heated in an oven at 270° Fahrenheit (“F.”) for fifteen minutes. The heat-set multifilament yarn used in the woven carpet backing of the present invention may only shrink between zero percent (0%) and five percent (5%) after it has been heated in an oven at 270° F. for fifteen minutes. Large differentials in the shrinkage between the heat-set monofilament yarn and the heat-set multifilament yarn, when the yarns are used together in the present invention, should be avoided. In the example described above, the shrinkage of the heat-set monofilament yarns and the shrinkage of the heat-set multifilament yarns should differ by no more than three percentage points from each other.
By way of one example for heat-setting monofilament fibers, a material is extruded and stretched to form a monofilament fiber. The fiber is placed on one or more heated cylinders (or “cans”) of varying speeds to heat-set the monofilament fiber. The cans are heated so that the monofilament fiber reaches a temperature of about 300 degrees F. to about 350 degrees F., and preferably about 310 degrees F. to about 320 degrees F., and most preferably to about 315 degrees F. The monofilament fiber is exposed to the heat for about two seconds to about ten seconds, and preferably about three seconds to about four seconds. By way of one example of heat-setting multifilament fibers, multifilament fibers are laid on a belt such that the fibers lay on the belt without tension. The belt, and therefore the multifilament yarns, pass through an oven, where the multifilament yarns are heat-set. The temperature the monofilament and multifilament fibers are exposed to, and the amount of time the fibers are exposed at a particular temperature vary depending on type of material of the fibers and other factors (e.g., a higher temperature may require less exposure time for the yarn to achieve the heat-setting results). By way of another example for heat-setting a polyester yarn, the heating means for heat-setting a yarn may heat the yarn to a sufficiently high temperature, but below its melting point, to stabilize the yarn and increase the crystallization in the yarn material. Hot air, steam, and infra-red heat may be used for heating the fiber in the heat-setting process. Heat-setting a polyester yarn may involve heating the yarn to a temperature of about 125 degrees Celsius to about 185 degrees Celsius. This way of heat-setting a polyester yarn is described in U.S. Pat. No. 4,082,731, the teachings of which are incorporated herein by reference to the extent these teaching are not inconsistent with the present invention. Other ways of creating similar characteristics in the yarns, including similar shrinkage characteristics, may also be used.
The woven carpet backing of the present invention has the appearance of a primary carpet backing on the face of the woven carpet backing, and the appearance of a secondary carpet backing on the back of the woven carpet backing. The face of the woven carpet backing may be defined as the side of the woven carpet backing which, as the woven carpet backing is woven on a loom, faces upward. The face of the woven carpet backing is the side of the woven carpet backing which, once finished into a floor covering, such as a carpet, will be in contact with the floor. The back of the woven carpet backing may be defined as the side of the woven carpet backing which, as the woven carpet backing is woven on a loom, faces downward. The back of the woven carpet backing is the side of the woven carpet backing which, once finished into a floor covering, such as a carpet, will form the walking surface. According to an embodiment of the invention, the appearance of a primary backing on the back of the woven carpet backing and the appearance of a secondary backing on the face of the woven carpet backing may be achieved by placing substantially all of multifilament fill yarns on the face of the woven carpet backing, and substantially all of the monofilament fill yarns on the back of the woven carpet backing.
The term “substantially all of multifilament fill yarns on the face of the woven carpet backing” means that at the interlaces, at least fifty percent (50%) of all multifilament fill yarns are placed on the face of the woven backing. Interlaces refer to the intersections of the warp yarns and the fill yarns. Thus, if at the interlaces at least fifty percent (50%) of multifilament fill yarns are placed on the face of the woven backing (or fabric), then at least fifty percent (50%) of the multifilament fill yarns are located above a warp yarn at the interlaces of the face of the woven carpet backing. According to an embodiment of the invention, the woven carpet backing may be woven such that at the interlaces about fifty percent (50%) to about eighty-three percent (83.3%) of multifilament fill yarns are placed on the face of the woven carpet backing. By way of example, the non-traditional weaves illustrated in
The term “substantially all of monofilament fill yarns on the back of the woven carpet backing” means that at the interlaces at least fifty percent (50%) of monofilament fill yarns are placed on the back of the woven carpet backing. As described with regard to the multifilament fill yarns, the upper limit of the percentage of monofilament fill yarns at the interlaces on the back of the woven carpet backing is only limited by the limitations of machines used to weave the woven carpet backing.
a, and 5b provide another illustration of the weave of the embodiment illustrated in
a and 5b illustrate cross-sections of a woven carpet backing according to an embodiment of the invention, where the fill yarns have been overstuffed. By overstuffing the fill yarns, multifilament fill yarns (12, 16, 12a, 16a) are located above their adjacent monofilament fill yarns (14, 18, 14a, 18a). According to this embodiment of the invention, at least a portion of each multifilament fill yarn (12, 16, 12a, 16a) is in direct contact with at least a portion of each monofilament fill yarn (14, 18, 14a, 18a), as shown in
Thus, as
Overstuffing of the fill yarn is an important aspect of the invention. Overstuffing creates a face of the woven carpet backing with substantially all multifilament fill yarns, and a back of the woven carpet backing with substantially all the monofilament fill yarns. Thus, the woven carpet backing has a face with substantially all multifilament fill yarns accessible, and a back with substantially all monofilament fill yarns accessible. Overstuffing relates to the amount of yarns per inch used in a weave and the coverage factor (or “cover factor”) of the woven carpet backing. The coverage factor is the fraction of the surface area that is covered by the yarns. For example, the width of a monofilament fill yarn may be about 0.1 inches, and a monofilament fill yarn coverage factor of one hundred percent (100%) may be achieved by using monofilament fill yarns at 10 picks per inch (10×0.10 inches=1 inch). Overstuffing places more yarns in the fill to create a coverage factor of greater than 100%, thereby causing the fill yarns to overlap, as illustrated in
The woven carpet backing may have an imaginary face plane (62) and an imaginary back plane (64) (
The back plane (64) of the woven carpet backing is comprised substantially of the monofilament fill yarns. For example, as illustrated in
In any embodiment of the invention, monofilament fill yarns have a width of about 0.08 inches to about 0.12 inches, and preferably about 0.09 inches to about 0.10 inches, and more preferably about 0.095 inches, and a thickness of about 0.010 inches to about 0.050 inches, preferably about 0.015 inches to about 0.030 inches, and more preferably about 0.020 inches. Multifilament fill yarns have a diameter of about 0.01 inches to about 0.15 inches, preferably about 0.03 inches to about 0.1 inches. Monofilament warp yarns have a width of about 0.04 inches to about 0.06 inches, and preferably about 0.045 inches to about 0.055 inches, and more preferably about 0.050 inches, and a thickness of about 0.010 inches to about 0.050 inches, preferably about 0.015 inches to about 0.030 inches, and more preferably about 0.020 inches.
According to an embodiment of the invention, the coverage factor for monofilament fill yarns may be about ninety percent (90%) to about two hundred percent (200%), preferably about one hundred percent (100%) to about one hundred seventy percent (170%), and more preferably about one hundred three percent (103%). The total fill yarn coverage factor (for both the monofilament fill yarns and the multifilament fill yarns) may be about ninety percent (90%) to about three hundred percent (300%), preferably about one hundred percent (100%) to about two hundred percent (200%), and more preferably about one hundred fifty (150%). Other ranges of coverage factor may also be used.
a and 6b provide another illustration of the weave of the embodiment illustrated in FIG. 2. Elements and reference numbers in
Similarly to the embodiment of
Thus, as
a, 7b, 7c, and 7d provide another illustration of the weave of the embodiment illustrated in FIG. 3. Elements and reference numbers in
Similarly to the embodiment of
Thus, as
Placing substantially all of the multifilament fill yarns on one side of the woven carpet backing creates an accessible surface that is primarily multifilament in nature. Conversely, placing substantially all of the monofilament fill yarns on the other side of the woven carpet backing creates an accessible surface that is primarily monofilament in nature. Various factors, as described previously above, may contribute to this characteristic of the woven carpet backing. One such factor may include the close proximity between monofilament fill yarns and multifilament fill yarns. The bias exerted by the monofilament warp yarns on the multifilament fill yarns may also be a factor, thereby causing the multifilament fill yarns to be placed on the face of the woven carpet backing. Overstuffing fill yarns causes neighboring (or adjacent) fill yarns to overlap. Additionally, the alternating of monofilament yarns and multifilament yarns in the fill may be a factor. Other factors may also contribute to the aforementioned characteristics of the woven carpet backing.
The woven carpet backing of the invention may be characterized by certain properties. Measurement of some of such properties is defined in the art, as discussed below. The terms “grabbed” and “pulled” as used herein in connection with the description of the properties of the woven carpet backing of the invention are defined in ASTM Test Method D4632, (1991), discussed more fully below. The properties discussed below were determined in accordance with ASTM Test Method D4632. The woven carpet backing may break when it is grabbed and pulled along the warp yarns at a load of about 50 pounds to about 200 pounds and preferably about 100 to about 150 pounds. A five percent elongation when the woven carpet backing is grabbed and pulled along the warp yarns may occur at a load of about 10 pounds to about 25 pounds. The woven carpet backing may break when it is grabbed and pulled along the fill yarns at a load of about 50 pounds to about 200 pounds and preferably about 75 to about 125 pounds. A five percent elongation when the woven carpet backing is grabbed and pulled along the fill yarns may occur at a load of about 15 pounds to about 40 pounds, and preferably about 20 pounds to about 30 pounds.
Any weave which produces a woven fabric with the characteristics described herein may be used. Persons of ordinary skill in the art will readily understand how to produce the woven carpet backing of the invention from the above description, using conventionally available equipment, such as a loom which is capable of using two different types of fill yarns which are alternating.
Other embodiments and uses of the invention will be apparent to those skilled in the art from consideration of the specification and practice of the invention disclosed herein. The specification and examples should be considered exemplary only. The scope of the invention is defined by the claims appended hereto, and their equivalents.
This application claims priority as a continuation application from U.S. patent application Ser. No. 09/609,068, filed on Jun. 30, 2000 now U.S. Pat. No. 6,510,872, the disclosure of which is incorporated herein by reference, which claimed priority as a Continuation-in-Part application from U.S. patent application Ser. No. 09/348,760, filed on Jul. 7, 1999, now U.S. Pat. No. 6,435,220, the disclosure of which is incorporated herein by reference.
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| Number | Date | Country | |
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| Number | Date | Country | |
|---|---|---|---|
| Parent | 09609068 | Jun 2000 | US |
| Child | 10281224 | US |
| Number | Date | Country | |
|---|---|---|---|
| Parent | 09348760 | Jul 1999 | US |
| Child | 09609068 | US |
