BRIEF DESCRIPTION OF THE DRAWINGS
The invention will now be further described by way of example only and with reference to the drawings, which are briefly described as follows:
FIG. 1 is schematic view illustrating apparatus and process for forming various polyurethane-backed surface coverings.
FIG. 2 is a cross-sectional illustration of an exemplary polyurethane-backed surface covering incorporating a tufted face structure;
FIG. 3 is a cross-sectional illustration of an exemplary polyurethane-backed surface covering incorporating a woven face structure;
FIG. 4 is a cross-sectional illustration of an exemplary polyurethane-backed surface covering incorporating a non-woven face structure;
FIG. 5 is a cross-sectional illustration of an exemplary polyurethane-backed surface covering incorporating a bonded pile face structure;
FIG. 6 is schematic view illustrating apparatus and process for forming various surface coverings incorporating backed polyurethane;
FIG.7 is a cross-sectional illustration of an exemplary surface covering incorporating a tufted face structure in contacting relation to a backed polyurethane layer;
FIG. 8 is a cross-sectional illustration of an exemplary surface covering incorporating a woven face structure in contacting relation to a backed polyurethane layer;
FIG. 9 is a cross-sectional illustrational of an exemplary surface covering incorporating a non-woven face structure in contacting relation to a backed polyurethane layer;
FIG. 10 is a cross-sectional illustration of an exemplary surface covering incorporating a bonded pile face structure in contacting relation to a backed polyurethane layer;
FIG. 11 is schematic view illustrating apparatus and process for forming various surface coverings incorporating stabilized polyurethane;
FIG. 12 is a cross-sectional illustration of an exemplary surface covering incorporating a tufted face structure in contacting relation to a stabilized polyurethane layer;
FIG. 13 is a cross-sectional illustration of an exemplary surface covering incorporating a woven face structure in contacting relation to a stabilized polyurethane layer;
FIG. 14 is a cross-sectional illustration of an exemplary surface covering incorporating a non-woven face structure in contacting relation to a stabilized polyurethane layer;
FIG. 15 is a cross-sectional illustration of an exemplary surface covering incorporating a bonded pile face structure in contacting relation to a stabilized polyurethane layer;
FIG. 16 is schematic view illustrating apparatus and process for forming various surface coverings incorporating stabilized and backed polyurethane;
FIG. 17 is a cross-sectional illustration of an exemplary surface covering incorporating a tufted face structure in contacting relation to a stabilized and backed polyurethane backing;
FIG. 18 is a cross-sectional illustration of an exemplary surface covering incorporating a woven face structure in contacting relation to a stabilized and backed polyurethane backing;
FIG. 19 is a cross-sectional illustration of an exemplary surface covering incorporating a non-woven face structure in contacting relation to a stabilized and backed polyurethane backing; and
FIG. 20 is a cross-sectional illustration of an exemplary surface covering incorporating a bonded pile face structure in contacting relation to a stabilized and backed polyurethane backing;
FIG. 21 is a cross-sectional illustration of an exemplary surface covering like that of FIG. 2 with the addition of a backing such as a coating, film, or the like;
FIG. 22 is a cross-sectional illustration of an exemplary surface covering like that of FIG. 7 with the addition of a backing such as a coating, film, or the like;
FIG. 23 is a cross-sectional illustration of an exemplary surface-covering like that of FIG. 12 except that the stabilizing layer or material is adjacent or abutting the tufts;
FIG. 24 is a cross-sectional illustration of an exemplary surface covering like that of FIG. 13 except that the stabilizing layer or material is near or on the bottom of the polyurethane backing;
FIG. 25 is a cross-sectional illustration of an exemplary surface covering like that of FIG. 3 except that it is inverted as constructed using an exemplary apparatus and process as shown in FIG. 27;
FIG. 26 is a cross-sectional illustration of an exemplary surface covering like that of FIG. 8 except that it is inverted like in FIGS. 25 and 27; and,
FIG. 27 is a schematic illustration of an exemplary apparatus and process for forming polyurethane backed surface coverings in accordance with another embodiment of the present invention.
DETAILED DESCRIPTION
Referring to FIG. 1 of the drawings, an exemplary formation system 10 is illustrated for use in the production of surface coverings or polyurethane backed products such as carpeting, carpet tile, area rugs, roll goods, and/or floor mats. According to the illustrated and potentially preferred embodiment, the formation system 10 includes an endless belt 12 formed from a material such as PTFE woven fiberglass or the like. As shown according to the illustrated process, a mass of uncured polyurethane composition 14 is preferably deposited directly onto the belt 12 and then adjusted to a desired height by a leveller 16 such as a doctor blade, air knife, or the like. The thickness of the levelled polyurethane composition is preferably in the range of about 0.10 inches to about 1.0 inches, more preferably about 0.16 inches to about 0.60 inches although higher or lower thickness levels may likewise be used. While direct application of the polyurethane composition onto the belt 12 may be preferred, it is likewise contemplated that a release layer, film, paper or the like (not shown) or other deposit surface may likewise be used if desired.
By way of example only, one contemplated polyurethane composition is believed to be disclosed in U.S. Pat. No. 5,104,693 to Jenkines, the teachings of which are incorporated herein by reference in their entirety. Fillers, agents, additives, extenders, and the like such as calcium carbonate, coal fly ash, sand, used foundry sand, crushed glass, crushed recycled glass, crushed gypsum, caster oil, foam chips, recycled carpet tile, natural and/or synthetic fibers, colorants, anti-microbial agents, flame retardants, blowing agents, catalyst, water, recycled materials, renewable materials, bio-based materials, post-consumer recycled materials, post-industrial recycled materials, and/or the like. Fillers may be added at amounts of about 0.0% to about 99% by weight, most preferably about 10% to about 90% by weight, and more preferably from about 20% to about 80% by weight. Fillers, agents, additives, extenders, and/or the like may be added in combination with air mixing to provide density levels as desired. A froth density of about 887 grams per litre has been found to provide good results.
In accordance with one example of an indoor/outdoor polyurethane backed area rug having a construction like that of FIG. 2 of the drawings, a preferred polyurethane backing which serves as precoat and backing is a mechanically frothed MDI based polyurethane having an about 750 gram cup weight and an about 27 oz/yd2 add on.
Potentially preferred filler examples include:
Used foundry sand—50% to 80% by weight
Crushed glass—65% by weight
Calcium carbonate—50% to 65% by weight
Coal fly ash—50% by weight
Blend of used foundry sand and calcium carbonate—% by weight
- 13% UFS and 44% calcium carbonate
- 21 % UFS and 40% calcium carbonate
- 26% UFS and 37% calcium carbonate
Blend of calcium carbonate and 40 mesh ground tires (SBR)—% by weight 55% calcium carbonate and 10% SBR As illustrated, once the polyurethane composition 14 is set to a desired level, a textile face structure 20 with a fibrous underside is preferably delivered into direct contacting relation with the polyurethane composition. For polyurethane backed products such as carpet, area rugs and mats, preferably, no intermediate layer is disposed between the polyurethane and the underside of the textile face structure (see FIGS. 2-5). According to one contemplated practice, the textile face structure 20 may be pre-treated at a steam box 22 to relieve internal stresses by application of moisture and heat. Such treatment permits the face structure 20 to remain substantially tensionless during subsequent curing of the polyurethane composition 14 as will be described further hereinafter. The elimination of tension in the face structure 20 facilitates the avoidance of undue levels of cupping or curling in the final structure. It is preferred that the polyurethane backing be thin, dense, and flexible and that the face material or fabric be substantially tensionless. Such a product lies flat on the floor, can be bent or rolled, and the like.
Following introduction of the textile face structure 20 across the polyurethane composition 14, the resulting composite structure may thereafter be moved through an elevated temperature curing range 26. The temperature in the curing range is set to prove substantially complete curing of the polyurethane composition 14. By way of example only and not limitation, such a curing range 26 having, for example, heated platens below belt 12, a platen temperature setting of about 250 degrees F. in a first zone, and with a setting of about 290 degrees F. in subsequent zones has been found to provide good curing results when the belt 12 is operating at a rate of about 30 feet per minute. Of course, these setting may be readily adjusted as desired. For example, certain polyurethane backings may cure at room temperature.
As shown, upon exiting the curing range 26, the composite structure with cured polyurethane may thereafter be removed from the belt 12 and sent to a cutter 30 for segmentation to a length and width as desired based on the final intended use or rolled to be cut later. Cutter 30 may be a clicker for carpet tiles, a cut table for mats or rugs, or a slitter. Accordingly, the formation system 10 may be used to form carpet, carpet tile, area rugs, roll goods, and/or floor mats as may be desired. In this regard, it is to be understood that the density and thickness levels of polyurethane may be adjusted depending upon the product being produced. Specifically, it is contemplated that the mass per unit area of polyurethane may be slightly higher for carpeting than for floor mats. By way of example only, it has been found that a polyurethane mass per unit area of about 26 to 28 ounces per square yard with a thickness of about 63 mils may be suitable for carpeting while a mass per unit area of about 25 ounces per square yard with a thickness of about 100 mils may be more suitable for dust control mats.
As previously noted, the textile face structure 20 may have any number of suitable constructions. By way of example only, FIGS. 2-5 illustrate a number of polyurethane-backed constructions such as may be formed on the system 10 using various face structures.
FIG. 2 illustrates a tufted textile face structure 20 incorporating an arrangement of yarn elements 36 tufted through a so called “primary backing” 38 such as a woven material, a scrim, a non-woven material, combined woven and non-woven material, or the like. As shown, the cured polyurethane composition 14 extends substantially to the primary backing 38 thereby aiding in locking the yarn elements 36 in place.
FIG. 3 illustrates a woven textile face structure 20A disposed in contacting relation to the cured polyurethane composition 14. As shown, the cured polyurethane composition 14 extends substantially to the surface of the woven textile face structure 20A and preferably migrates at least partially into the interstices between yarn elements forming the woven textile face structure 20A so as to promote good adhesion.
FIG. 4 illustrates a non-woven textile face structure 20B such as a needle punched, flocked, spunbond or other non-woven construction disposed in contacting relation to the cured polyurethane composition 14. As shown, the cured polyurethane composition 14 extends substantially to the surface of the non-woven textile face structure 20B and preferably migrates at least partially into the interstices between fiber elements forming the non-woven textile face structure 20B so as to promote good adhesion.
FIG. 5 illustrates a bonded yarn textile face structure 20C incorporating an arrangement of yarn elements 37 bonded in place across a primary backing or substrate layer 44 by an adhesive 42 disposed across the upper surface of the primary backing layer 44. Although a loop pile is shown, the pile may be loop, cut, or cut and loop. As shown, the cured polyurethane composition 14 preferably extends substantially to the primary backing 44.
As indicated previously, it is also contemplated that one or more backing or release layers may be applied across the underside of the cured polyurethane facing away from the textile face structure. By way of example only, FIG. 6 illustrates a formation system 110 for production of surface coverings incorporating backed polyurethane, such as felt backed polyurethane, wherein elements corresponding to those previously described are designated by like reference numerals increased by 100. As will be appreciated, the formation system 110 is substantially identical to the system illustrated and described in relation to FIG. 1 but with the addition of backing material, such as felt 140 across the belt 112 at a position upstream of the location at which the polyurethane composition 114 is deposited.
By way of example only, one felt that may be particularly preferred is a needle punched felt formed from polyester and/or polypropylene as described in U.S. Pat. No. 5,540,968 hereby incorporated by reference herein. Of course other woven and/or non-woven backings may likewise be utilized as desired.
The textile face structure 120 may have any number of suitable constructions. By way of example only, FIGS. 7-10 illustrate a number of backed polyurethane constructions such as may be formed on the system 110 using various face structures.
FIG. 7 illustrates a tufted textile face structure 120 incorporating an arrangement of yarn elements 136 tufted through a primary backing 138 such as a woven, a non-woven or the like. As shown, the cured polyurethane composition 114 extends substantially between the backing, such as non-woven felt 140 and the primary backing 138 thereby aiding in locking the yarn elements 136 in place.
FIG. 8 illustrates a woven textile face structure 120A disposed in contacting relation to the cured polyurethane composition 114. As shown, the cured polyurethane composition 114 extends substantially between the backing, such as non-woven felt 140 and the surface of the woven textile face structure 120A and preferably migrates at least partially into the interstices between yarn elements forming the woven textile face structure 120A so as to promote good adhesion.
FIG. 9 illustrates a non-woven textile face structure 120B such as a needle punched, flocked, spun bond or other non-woven construction disposed in contacting relation to the cured polyurethane composition 114. As shown, the cured polyurethane composition 114 extends substantially between the felt backing, such as a non-woven 140 and the surface of the non-woven textile face structure 120B and preferably migrates at least partially into the interstices between fiber elements forming the non-woven textile face structure 120B so as to promote good adhesion.
FIG. 10 illustrates a bonded yarn textile face structure 120C incorporating an arrangement of yarn elements 137 bonded in place across a primary backing or substrate layer 144 by an adhesive 142 disposed across the upper surface of the primary backing layer 144. As shown, the cured polyurethane composition 114 preferably extends substantially between the backing, such as a non-woven felt 140 and the primary backing 144,
The backings 140 of FIGS. 6-10 may be a woven, non-woven, or combined woven and non-woven material or fabric, a film, a scrim, a mesh, or combinations thereof. In accordance with one example, the backing 140 is a non-woven bonded glass material marketed as STABILON TRIAX™ by Milliken & Company of Spartanburg, S.C. It is preferred that the backing 140 be a flexible material which prevents growth and which tends to prevent curling of the surface covering 120 (such as a carpet tile). A glass scrim, mat, or the like may be preferred.
As indicated previously, it is also contemplated that one or more structural support layers may placed within the cured polyurethane. By way of example only, FIG. 11 illustrates a formation system 210 for production of surface coverings incorporating polyurethane with an intermediate structural support layer, wherein elements corresponding to those previously described are designated by like reference numerals in a 200 series.
As will be appreciated, the formation system 210 is substantially identical to the system illustrated and described in relation to FIG. 1 but with the addition of a structural support layer 250, such as a glass mat or scrim, between deposited layers of polyurethane composition 214, 214–. As shown, in the illustrated practice the structural support layer 250 is placed in contacting overlying relation to a first layer of polyurethane composition 214 following a first leveller 216. A second layer of polyurethane composition 214′ is then applied across the structural support layer 250 followed by a leveller 216′ thereby yielding a sandwich structure for application of the textile face structure 220.
With reference to FIGS. 11-15, 23 and 24 of the drawings, the location of support, stabilizing or reinforcement layer or material 250 can be determined by the amount of polyurethane composition added upstream and downstream of the support layer 250. Although it may be preferred that the support layer 250 be located at the top of, in the middle of, or at the bottom of the polyurethane backing (FIGS. 23, 12, and 24, respectively), it may be located anywhere in between by controlling the add of polyurethane 214 and 214′ in the system of FIG. 11.
By way of example only, one structural support layer 250 is in the form of woven or non-woven glass, although other materials including polyester, polypropylene, and the like may also be utilized if desired. The textile face structure 220 may have any number of suitable constructions. By way of example only, FIGS. 12-15 illustrate a number of constructions incorporating a structural support layer 250 such as may be formed on the system 210 using various face structures.
FIG. 12 illustrates a tufted textile face structure 220 incorporating an arrangement of yarn elements 236 tufted through a primary backing 238 such as a scrim, a non-woven or the like. As shown, the upper layer of cured polyurethane composition 214′ extends substantially between the structural support layer 250 and the primary backing 238 thereby aiding in locking the yarn elements 236 in place. The lower layer of cured polyurethane composition 214 extends away from the structural support layer 250 to define a lower surface.
FIG. 13 illustrates a woven textile face structure 220A disposed in contacting relation to the upper layer of cured polyurethane composition 214′. As shown, the upper layer of cured polyurethane composition 214′ extends substantially between the structural support layer 250 and the underside of the woven textile face structure 220A and preferably migrates at least partially into the interstices between yarn elements forming the woven textile face structure 220A so as to promote good adhesion. The lower layer of cured polyurethane composition 214 extends away from the structural support layer 250 to define a lower surface.
FIG. 14 illustrates a non-woven textile face structure 220B such as a needle punched, flocked, spun bond or other non-woven construction disposed in contacting relation to the upper layer of cured polyurethane composition 214′. As shown, the upper layer of cured polyurethane composition 214′ extends substantially between the structural support layer 250 and the underside of the non-woven textile face structure 220B and preferably migrates at least partially into the interstices between fiber elements forming the non-woven textile face structure 220B so as to promote good adhesion. The lower layer of cured polyurethane composition 214 extends away from the structural support layer 250 to define a lower surface.
FIG. 15 illustrates a bonded yarn textile face structure 220C incorporating an arrangement of yarn elements 237 bonded in place across a primary backing or substrate layer 244 by an adhesive 242 disposed across the upper surface of the primary backing layer 244. As shown, the upper layer of cured polyurethane composition 214′ extends substantially between the structural support layer 250 and the underside of the primary backing layer 244. The lower layer of cured polyurethane composition 214 extends away from the structural support layer 250 to define a lower surface.
It is also contemplated that combinations of structural support layers and backings, such as felt backings, may be utilized. By way of example only, FIG. 16 illustrates a formation system 310 for production of surface coverings incorporating polyurethane with an intermediate structural support layer and with a backing. In this figure and related figures, elements corresponding to those previously described are designated by like reference numerals within a 300 series. As will be appreciated, the formation system 310 is substantially identical to the system illustrated and described in relation to FIG. 11 but with the addition of a layer of backing such as felt 340 across the belt 312 at a position upstream of the location at which the polyurethane composition 314 is deposited.
As shown, in the illustrated practice a first layer of polyurethane composition 314 is deposited over the backing material or layer 340 and levelled by a first leveller 316. The structural support layer 350 is placed in contacting overlying relation to the first layer of polyurethane composition 314 following a first leveller 316. A second layer of polyurethane composition 314′ is then applied across the structural support layer 350 followed by a leveller 316′ thereby yielding a stabilized and backed sandwich structure for application of the textile face structure 320.
The textile face structure 320 may have any number of suitable constructions. By way of example only, FIGS. 17-20 illustrate a number of constructions incorporating a structural support layer 350 and a backing 340 such as may be formed on the system 310 using various face structures.
FIG. 17 illustrates a tufted textile face structure 320 incorporating an arrangement of yarn elements 336 tufted through a primary backing 338 such as a woven, a non-woven or the like. As shown, the upper layer of cured polyurethane composition 314′ extends substantially between the structural support layer 350 and the primary backing 338 thereby aiding in locking the yarn elements 336 in place. The lower layer of cured polyurethane composition 314 extends away from the structural support layer 350 to the backing layer 340.
FIG. 18 illustrates a woven textile face structure 320A disposed in contacting relation to the upper layer of cured polyurethane composition 314′. As shown, the upper layer of cured polyurethane composition 314′ extends substantially between the structural support layer 350 and the underside of the woven textile face structure 320A and preferably migrates at least partially into the interstices between yarn elements forming the woven textile face structure 320A so as to promote good adhesion. The lower layer of cured polyurethane composition 314 extends away from the structural support layer 350 to the backing layer 340.
FIG. 19 illustrates a non-woven textile face structure 320B such as a needle punched, flocked, spun bond or other non-woven construction disposed in contacting relation to the upper layer of cured polyurethane composition 314′. As shown, the upper layer of cured polyurethane composition 314′ extends substantially between the structural support layer 350 and the underside of the non-woven textile face structure 320B and preferably migrates at least partially into the interstices between fiber elements forming the non-woven textile face structure 320B so as to promote good adhesion. The lower layer of cured polyurethane composition 314 extends away from the structural support layer 350 to the backing layer 340.
FIG. 20 illustrates a bonded yarn textile face structure 320C incorporating an arrangement of yarn elements 337 bonded in place across a primary backing or substrate layer 344 by an adhesive 342 disposed across the upper surface of the primary backing layer 344. As shown, the upper layer of cured polyurethane composition 314′ extends substantially between the structural support layer 350 and the underside of the primary backing layer 340. The lower layer of cured polyurethane composition 314 extends away from the structural support layer 350 to the layer of felt 340.
With reference to FIG. 21, a tufted face surface covering like that of FIG. 2 is shown with a backing 60 such as a coating, film, or the like. For example, backing 60 may be an adhesive or other friction enhancing coating such as TractionBack coating offered by Milliken & Company of LaGrange, Ga.
Similarly, the tufted face surface covering of FIG. 22 is like that of FIG. 7 with the addition of backing 160 such as a coating, film, or the like.
The tufted face surface covering of FIG. 23 is like that of FIG. 12 except that the support layer 250 is shown just below tufts 236.
The woven face surface covering of FIG. 24 is like that of FIG. 13 except that the support layer 250 is shown at the bottom of polyurethane 214.
FIGS. 25-27 relate to an alternative production process wherein the face material 20, 120, 220 is inverted and then laid on the belt 112. Next, polyurethane composition 114 is poured or applied to the back of the face material 20A or 120A and doctored by blade 116.
With respect to FIGS. 26 and 27, a backing 140 is added over the polyurethane 114 and nip or gauge roll 162 presses backing 140 into the polyurethane 114.
One advantage of the system 110A of FIG. 27 is that the face material 120 tends to keep the belt 112 clean of polyurethane 114.
The face material 20, 20A, 20B, 20C, 120, 120A, 120B, 120C, 220, 220A, 220B, 220C, 320, 320A, 320B, and 320C may be formed of natural or synthetic fibers or materials, or blends thereof. For example, tufts 36 may be Nylon 6, Nylon 6,6, polyolefin, wool, or blends thereof.
If face material 20 must be dyed, it is preferred that it be dyed prior to addition of polyurethane 14.
Polyurethane 14 may include a polyol component, an isocyanate component, a catalyst, and other agents, fillers, additives, and the like. It has been discovered that the catalyst may be eliminated, that the polyol may be replaced with caster oil, or both.
The surface coverings of the present invention may be hardback or cushion back products. One can increase the cushion or resilience of the backing by adding more air, more blowing agent, felt, thickness, or the like. It is possibly preferred that a polyurethane hardback or cushion back product such as a polyurethane hardback or cushion back carpet tile have the structure of one of FIGS. 2-5, 7-10, 12-15, 17-20, and 21-26. It may also be preferred that a polyurethane backed area rug, roll goods, or floor mat of the present invention have the structure of one of FIGS. 2-5, 21, and 25.
In accordance with a particular example of an indoor/outdoor polyurethane backed area rug having a structure like that of FIG. 2, a tufted face greige carpet material (no precoat) had a cut pile, Nylon 6,6, jet dyed, 20 oz/yd2 face yarn, 8th gauge, tufted through a 4 oz/yd2 non-woven, polyester primary backing, was laid over a mechanically frothed, MDI based polyurethane at a 750 gram cup weight and an average add-on of 27 oz/yd2. The uncured polyurethane composition was poured onto a belt, doctored and then joined to the carpet greige goods under a marriage roll. The polyurethane was cured under heat.
In accordance with another example, an indoor/outdoor polyurethane backed area rug had an overall average height of about 7458.03 μm (micrometers), an average polyurethane backing height of about 1507.64 μm (micrometers), and a total weight of about 51.79 oz/yd2.
In accordance with at least selected embodiments of the present invention, a nip, marriage, or gauge roll 62 (FIG. 1), 162, (FIG. 6), 262 (FIG. 11), 362 (FIG. 16) presses the face material 20, 120, 220, 320 into the uncured polyurethane composition and sets the height of the total product (prior to any chemical blowing).
The surface covering of the present invention may in at least one embodiment be 6 foot wide roll goods sometimes referred to a 6 foot broadloom.
While the present invention has been illustrated and described in relation to certain potentially preferred embodiments and practices, it is to be understood that the illustrated and described embodiments and practices are illustrative only and that the present invention includes such embodiments but is not limited thereto. Rather, it is fully contemplated that modifications and variations to the present invention will no doubt occur to those of skill in the art upon reading the above description and/or through practice of the invention. It is therefore intended that the present invention shall extend to all such modifications and variations as may incorporate the broad principles of the present invention within the full spirit and scope thereof.
Patent Application
20080085391
