Patent Application
20080052884
A full and enabling disclosure of the present invention, including the best mode thereof, directed to one of ordinary skill in the art, is set forth more particularly in the remainder of the specification, which makes reference to the appended Figs. in which:
Repeat use of reference characters in the present specification and drawings is intended to represent the same or analogous features or elements of the invention.
Reference will now be made in detail to embodiments of the invention, one or more examples of which are illustrated in the drawings. Each example is provided by way of explanation of the invention, and not meant as a limitation of the invention. For example, features illustrated or described as part of one embodiment can be used with another embodiment to yield still a third embodiment. It is intended that the present invention include these and other modifications and variations.
It is to be understood that the ranges mentioned herein include all ranges located within the prescribed range. As such, all ranges mentioned herein include all sub-ranges included in the mentioned ranges. For instance, a range from 100-200 also includes ranges from 110-150, 170-190, and 153-162. Further, all limits mentioned herein include all other limits included in the mentioned limits. For instance, a limit of up to 7 also includes a limit of up to 5, up to 3, and up to 4.5.
The present invention provides for a fabric and a method of forming a fabric that has a twill weave with a satin face. The fabric can be formed with a float of 3/1 or 4/1 and may have a width of at least 102 inches, and preferably about 124 inches. Other embodiments exist in which the width may be from 102 inches to 131 inches.
The method, in accordance with one exemplary embodiment of the present invention, involves weaving on a loom a polyester warp yarn having about 140-150 denier with about 36-100 filaments in a single-ply form, although two-ply is possible in other embodiments. Also woven is a polyester two-ply yarn of about 140-150 denier weft yarn with between about 36-110 filaments and a pick count of 55. The fabric is woven at a width of about 124 inches. The yarn can be made from either plain polyester or may be made of 100% fire retardant polyester. Alternatively, the yarn can be made with a blend of fire retardant polyester and plain polyester, which is useful for heat transfer printing of fabrics.
The yarn may be put through a sewing and batching process on an A-frame. Here, the yarn is formed into a fabric such as a 3/1 or 4/1 twill weave that has a satin face. The ends of the fabric are single ply in one embodiment. Further, 110 or more ends may be present in accordance with other exemplary embodiments. The warp yarns of the fabric are oriented in the length-wise direction and extend in the machine direction during subsequent processing. The weft yarns of the fabric extend in the cross-direction and hence along the width of the fabric. The width of the fabric may be from 102 to 131 inches in accordance with certain exemplary embodiments. In accordance with one exemplary embodiment, the width of the fabric is 124 inches.
Following weaving, the fabric is then typically taken to a second location and subjected to various procedures such as finishing or preparation steps using conventional protocols. In such procedures the fabric may be, for example, dyed and/or treated so as to be fire retardant. Thereafter, in a subsequent treatment step, the fabric is sanded at a rate of 20 yards per minute. However, it is to be understood that sanding at different rates may be employed in other embodiments. For example, the fabric can be sanded at a rate up to 30 yards per minute or may sanded at a rate up to 15 yards per minute. The longer floats of the fabric result in ends that are not tied down and hence sand more evenly to achieve a more desirable fabric finish.
Sanding is accomplished by passing the fabric surface(s) over a plurality of rollers. The rollers can be provided with a rough surface for treating the fabric. For example, the rollers can have sand paper surfaces in one embodiment. In accordance with one exemplary embodiment of the present invention four rollers with sand paper surfaces are used in order to treat the fabric. However, it is to be understood that any number of rollers can be used in other embodiments and that their surfaces need not be rough. In one embodiment, the fabric is passed over a first roller that rotates in a first direction and has a 120 grit sand paper surface. The first roller presses onto the fabric surface in order to cause 3 inches of compression thereto.
A second roller can be employed and may have a 100 grit sand paper surface. The second roller can rotate in a direction opposite to the first roller and may be tensioned against the fabric so as to cause 7 inches of compression thereto. A third roller may also be employed and can have a 100 grit sand paper surface. The third roller may, as with the second roller, rotate in a second direction. The third roller is tensioned against the fabric in order to cause 7 inches of compression. The fabric may also be passed over a fourth roller that has a 120 grit sand paper surface. The fourth roller, like the first roller, rotates in the first direction. The fourth roller is configured in order to be urged against the fabric so as to cause 5 inches of compression thereto.
The first direction that the first and fourth rollers rotate may be the counter clockwise direction. The second direction in which the second and third rollers rotate can be opposite that of the first direction and may be in the clockwise direction. In other versions of the present invention, the first, second, third and fourth rollers may rotate in directions other than those disclosed above. The rollers can be driven so they urge the fabric in the machine direction. Alternatively, the rollers can be free turning so they do not act to urge the fabric in the machine direction. In other configurations, some of the rollers may be driven while others are free turning. Further, although described as having sand paper surfaces, the rollers need not actually have sand paper applied thereto. Instead, the surfaces of the rollers may be rough so as to result in possessing a grit quality much like a piece of sand paper. Although described as imparting a certain amount of compression onto the fabric, the rollers may apply various amount of compression in other embodiments. Additionally, one or more of the rollers need not apply any amount of compression in other versions of the disclosed method.
Heretofore, efforts to sand large width fabrics, defined here as fabrics having a width equal to or in excess of 102 inches have not been commercially viable. Variations in the tension of the fabric and uniformity of the sanding rollers results in uneven areas of the fabric. It has been found that in accordance with the present invention using an exemplary fabric as described above, including fabrics which have been dyed or treated with fire retardant coatings, a large width fabric, such as a 124 inch width fabric can be sanded to result in a fabric having a high quality hand with a uniform finish from edge to edge.
After sanding, the fabric is placed on a tenter frame and stretched a certain percentage of the fabric's relaxed length. For example, the fabric may be stretched 2% of the fabric's relaxed length. The fabric may be stretched along its width. As previously mentioned, the lengthwise direction of the fabric is in the same direction in which the warp yarns extend and is in the same direction as the machine direction of the rollers. The width of the fabric is perpendicular to the lengthwise direction of the fabric and is in the same direction as that in which the weft yarns extend.
In the disclosed method, the fabric can be treated once the fabric is applied to the tenter frame. For example, an agent may be applied to the fabric in order to improve various properties of the fabric such as soil release and pilling. In accordance with one exemplary embodiment, a chemical agent such as 2% LUBRIL® can be applied to the fabric after the fabric is applied to the tenter frame in order to improve soil release and improve pilling properties of the fabric. 2% LUBRIL® is distributed by Resolution Specialty Materials having offices located at 200 Railroad Street, Roebuck, S.C. 29376. The soil release property of the fabric relates to the ease with which dirt and other unwanted particles can be removed from the fabric upon washing. When used in items such as clothing and curtains, it is desirable for the article to easily release dirt contained thereon during cleaning. The pilling property of the fabric relates to the tendency of fibers of the fabric to interlock or knot with one another so as to form clumps on the surface of the fabric. Again, it is usually desirable for fabric used in applications such as clothing and curtains to have a minimum of pilling. Although described as being used in order to improve the soil release and pilling properties of fabric, it is to be understood that in other embodiments different types of agents may be applied to the fabric in order to modify other properties of the fabric.
While on the tenter frame, the fabric may be moved at a speed from 15 to 35 yards per minute. Other speeds are possible in other versions of the method. For example, the fabric may be moved at speeds up to 75 yards per minute in other embodiments.
The fabric is also heated to a temperature of 385 degrees Fahrenheit during application of the agent to the fabric. Heating of the fabric during application of the agent may act to impart durability and optimize performance of the agent. In other embodiments, the fabric may be heated before, after and/or during application of the agent. Further, the temperature to which the fabric is heated may vary. For example, the fabric may be heated to a temperature of from 380-420 degrees Fahrenheit. The tenter frame holds the fabric and maintains its stretch so that when dried the fabric does not shrink.
By employing rollers and a tenter frame that have elongated widths, the fabric is capable of being formed so that its width is about 124 inches. As such, the fabric can be formed with a desired width for a particular application without the need to sew two or more pieces of fabric together to achieve the desired width. This ability may be advantageous in that print patterns on two or more pieces of fabric do not need to be aligned with one another in forming a resultant fabric with a desired width. Further, as the fabric can be made to have a desired width the fabric can also be made without the presence of seams.
Twill weave fabrics with a satin face generally have fewer interlacings and allow for more yarns per square inch to be used. These types of weaves also normally result in fabrics with better hand properties, more wrinkle resistance, more soil resistance, and more durability than plain weave fabrics. Also, twill weave fabrics with a satin face tend to have a more defined face and backside.
While the present invention has been described in connection with certain preferred embodiments, it is to be understood that the subject matter encompassed by way of the present invention is not to be limited to those specific embodiments. On the contrary, it is intended for the subject matter of the invention to include all alternatives, modifications and equivalents as can be included within the spirit and scope of the following claims.
Experiments were conducted in accordance with various exemplary embodiments of the present invention. One such experiment measured the amount of pilling of the fabric. Pilling of the fabric involves the formation of fuzz balls on the face of the fabric that are formed by abrasion. A rating system is used in order to evaluate the pilling properties of a particular fabric:
Several specimens were tested to evaluate pilling properties as per an ASTM D 3512 testing procedure which is a standard test method for pilling resistance and other related surface changes of textile fabrics. This test method is sometimes known as a random tumble filling tester method. The specimens were treated in a manner as disclosed in the present application. The results were as follows:
Although the 3 specimens tested that were made in accordance with the present invention rated as a class 5, they were found to have a slight degree of fuzzing of their outer surface.
Additional experiments were carried out on fabrics produced in accordance with the method of the present application. Further experiments were directed towards evaluating the wetting property of the fabric. Wetting is a test of the ability of water or another cleaning liquid to pass through the fabric. A rating system was used to evaluate the property of wetting:
A spray test was performed using an AATCC test method 22. Here, water was sprayed against a taut surface of the test specimen under controlled conditions to produce a wetted pattern. The wetted pattern was compared with pictures on a standard chart in order to accomplish the evaluation. The results were as follows:
The wetting properties of fabric made in accordance with the present invention were found to have a wetting score of 0.
An additional experiment was carried out on fabric made in accordance with the present invention to determine fire retardance of the fabric. The test performed was an NFPA 701-2004 TM#1 which is a 2004 edition standard fire test for flame propagation of textiles and films. The minimum requirement for contract drapery is the NFPA 701 testing method. The fabric tested was configured as a single layer and the test results on the fabric were reported immediately after the flame test was conducted so that the fabric was not laundered before its evaluation. The test results were as follows:
The weight loss had a standard deviation (SD) of 6.1 so that 3×SD=18.3. The Mean+(3×SD)=40.6. The approximate weight of the material was measured to be 219 g/m3. The specimens were prepared in the length direction and were preconditioned for a length of time of 30 minutes at a temperature of 220° F. A conversion factor of g/m3+28.35×0.835=oz/yd2 was used.
Failure criteria under the selected test method is as follows:
Based on the failure criteria, the tested specimens pass the NFPA 701-2004 Edition test.
A revised failure criteria was also considered as follows:
In a similar manner, the specimens pass under the revised failure criteria. Although the NFPA document does not factor * Afterflame into the failure criteria reporting requirements, afterflame is recorded. It should be noted that excessive afterflame (15 seconds or more) may be cause for rejection of the product by local fire authorities performing “match” field tests.
Another test was carried out on fabric produced in accordance with the present invention to determine tearing strength. The test used was the ASTM D 2261 test which is a standard test method for tearing strength of fabrics by the tongue (single rip) procedure. The type of machine used in the test is a constant rate of extension tensile testing machine. Results of the test are as follows:
Additional experiments were carried out in order to determine the breaking force of the fabric. The test method employed was the ASTM D 5034 test method that is sometimes known as the grab test and is a standard test method for measuring the breaking force of textile fabrics. The results of this test are as follows:
Additional testing of the fabric was conducted. This additional test was the AATCC test method 135 that ascertained dimensional changes in automatic home laundering of woven and knit fabrics. The fabric was subjected to both one and five laundering cycles and a wash load of four pounds was used. The washing machine used was set at a normal/ctn/sturdy setting with a wash temperature of 160° F.+/−5° F. with a tumble dry of cotton/sturdy. The results are as follows (− indicating shrinkage and + indicating growth):
The ASTM D 4157-02 test was also conducted which is a standard test method for measuring abrasion resistance of textile fabrics and is sometimes known as an oscillatory cylinder method. Wire (steel) screen was selected as an abradant. The surface category into which the fabric falls is a special surface effect which is used for napped, chenille, embossed, textured and like fabrics. The specimen was tensioned at 4 pounds and a head pressure of 3 pounds was applied. The rating system special surface effects are as follows:
The test results obtained through visible observations are as follows:
Class 3 is generally considered to be the minimum passing rate for heavy duty commercial upholstery. Light duty upholstery standards are typically 9,000 rubs with class 3 performance.
