Molded composite fabrics and methods of making

Warren; Roger D. ;   et al.

Patent Application Summary

U.S. patent application number 11/267358 was filed with the patent office on 2006-08-24 for molded composite fabrics and methods of making. Invention is credited to Asli Begenir, Rick Kelley, Roger D. Warren.

Application Number20060189238 11/267358
Document ID /
Family ID36283156
Filed Date2006-08-24

United States Patent Application 20060189238
Kind Code A1
Warren; Roger D. ;   et al. August 24, 2006

Molded composite fabrics and methods of making

Abstract

A molded composite fabric and methods of making are provided. The molded composite fabric has a polyethylene foam layer and a first fabric layer adhered to a first side of the polyethylene foam layer to define a composite fabric. The molded composite fabric also includes a feature molded in the composite fabric. The first fabric layer has a non-woven fabric with a web of randomly disbursed fibers. The method includes selecting a non-woven fabric having a web of randomly disbursed fibers, exposing the non-woven fabric to mechanical agitation, laminating the non-woven fabric to a first side of a polyethylene foam layer to a composite fabric, compressing the composite fabric between a top mold and a bottom mold, and maintaining the composite fabric between the top and bottom molds for a predetermined dwell time.


Inventors: Warren; Roger D.; (Claremont, NC) ; Kelley; Rick; (Germantown, NC) ; Begenir; Asli; (Winston-Salem, NC)
Correspondence Address:
    Charles N.J. Ruggiero, Esq.;Ohlandt, Greeley, Ruggiero & Perle, L.L.P.
    10th Floor
    One Landmark Square
    Stamford
    CT
    06901-2682
    US
Family ID: 36283156
Appl. No.: 11/267358
Filed: November 4, 2005

Related U.S. Patent Documents

Application Number Filing Date Patent Number
60625491 Nov 5, 2004
60669604 Apr 8, 2005

Current U.S. Class: 442/182 ; 442/221; 442/328; 442/370
Current CPC Class: B32B 2250/02 20130101; Y10T 442/3325 20150401; Y10T 442/601 20150401; Y10T 442/647 20150401; B29C 51/08 20130101; Y10T 442/60 20150401; B32B 2307/738 20130101; D04H 1/558 20130101; A41C 5/005 20130101; B32B 2437/00 20130101; D04H 1/559 20130101; B29K 2105/04 20130101; B32B 5/08 20130101; B32B 5/24 20130101; B32B 2266/025 20130101; B29C 51/145 20130101; B29L 2031/4885 20130101; A41C 3/00 20130101; Y10T 442/3008 20150401; A41C 3/0014 20130101; B32B 5/022 20130101; B32B 5/245 20130101
Class at Publication: 442/182 ; 442/370; 442/328; 442/221
International Class: B32B 5/24 20060101 B32B005/24; D03D 15/08 20060101 D03D015/08; D04H 13/00 20060101 D04H013/00

Claims



1. A molded composite fabric, comprising: a polyethylene foam layer; a first fabric layer adhered to a first side of said polyethylene foam layer to define a composite fabric, said first fabric layer comprising a non-woven fabric having a web of randomly disbursed fibers; and a feature molded in said composite fabric.

2. The molded composite fabric of claim 1, wherein said web of randomly disbursed fibers comprises a uniform fiber orientation in all directions.

3. The molded composite fabric of claim 1, wherein said web of randomly disbursed fibers comprises fibers that are bonded to and/or entangled with one another.

4. The molded composite fabric of claim 1, wherein said web of randomly disbursed fibers comprises fibers selected from the group consisting of mono-component fibers, multi-component fibers, and any combinations thereof.

5. The molded composite fabric of claim 1, wherein said web of randomly disbursed fibers comprises fibers selected from the group consisting of nylon fibers, polypropylene fibers, polyester fibers, cotton fibers, wool fibers, hemp fibers, and any combinations thereof.

6. The molded composite fabric of claim 1, wherein said web of randomly disbursed fibers comprises fibers having two or more different diameters.

7. The molded composite fabric of claim 1, wherein said first fabric layer comprises multi-component fibers having a blend of a low-melting temperature polymer and a high-melting temperature polymer.

8. The molded composite fabric of claim 1, wherein said first fabric layer comprises at least two mono-component fibers, one of said at least two mono-component fibers having a low-melting temperature polymer and another of said at least two mono-component fibers having a high-melting temperature polymer.

9. The molded composite fabric of claim 1, wherein said first fabric layer is substantially rigid.

10. The molded composite fabric of claim 1, wherein said first fabric layer is elastic.

11. The molded composite fabric of claim 1, further comprising a second fabric layer adhered to a second side of said polyethylene foam layer.

12. The molded composite fabric of claim 1, further comprising a plurality of holes defined through said polyethylene foam layer.

13. The molded composite fabric of claim 1, wherein said feature is selected from the group consisting of a breast cup, a kneepad, a plurality of expanded sections, a pattern, a design, and any combinations thereof.

14. The molded composite fabric of claim 1, wherein said first fabric layer is adhered to said polyethylene foam layer by a material selected from the group consisting of a solvent-based adhesive, a web adhesive, a film adhesive, a dot adhesive, a sonic weld, and any combinations thereof.

15. The molded composite fabric of claim 1, wherein said first fabric layer is adhered to said polyethylene foam layer continuously or discontinuously.

16. A brassiere comprising: a garment body; and a pair of molded breast cups having a first fabric layer adhered to a first side of a polyethylene foam layer, said first fabric layer comprising a non-woven fabric having a web of randomly disbursed fibers.

17. The brassiere of claim 16, wherein said garment body comprises one or more layers of a woven fabric and/or a non-woven fabric.

18. The brassiere of claim 17, wherein said pair of molded breast cups comprise a pair of inserts secured to said garment body.

19. The brassiere of claim 16, wherein said garment body comprises said first fabric layer.

20. The brassiere of claim 16, further comprising a second fabric layer adhered to a second side of said polyethylene foam layer.

21. The brassiere of claim 16, further comprising a plurality of holes defined through said polyethylene foam layer.

22. A method of forming a molded non-woven fabric, comprising: selecting a non-woven fabric having a web of randomly disbursed fibers; exposing said non-woven fabric to mechanical agitation; laminating said non-woven fabric to a first side of a polyethylene foam layer to a composite fabric; compressing said composite fabric between a top mold and a bottom mold; and maintaining said composite fabric between said top and bottom molds for a predetermined dwell time.

23. The method of claim 22, wherein exposing said non-woven fabric to mechanical agitation comprises agitating said non-woven fabric in the presence of a wetting agent.

24. The method of claim 23, wherein said wetting agent comprises water and/or a fabric softener.

25. The method of claim 22, further comprising punching a plurality of holes through said polyethylene foam layer before laminating said non-woven fabric to said first side of said polyethylene foam layer.

26. The method of claim 22, further comprising heating said composite fabric to a molding temperature of less than about 375 degrees Fahrenheit.

27. The method of claim 26, wherein said predetermined dwell time is less than about 30 seconds.

28. The method of claim 22, further comprising heating said composite fabric to a molding temperature of about 300 degrees Fahrenheit, and wherein said predetermined dwell time is about 20 seconds.
Description



CROSS REFERENCE TO RELATED APPLICATIONS

[0001] This application claims the benefit of U.S. Provisional Application Ser. No. 60/625,491 filed on Nov. 5, 2004 and U.S. Provisional Application Ser. No. 60/669,604 filed on Apr. 8, 2005, the contents of both of which are incorporated by reference herein.

BACKGROUND OF THE INVENTION

[0002] 1. Field of the Invention

[0003] The present invention is related to molded composite fabrics and methods of making. More particularly, the present invention relates to composite fabrics having a layer of non-woven fabric and a layer of foam, where the composite fabrics include one or more features molded therein.

[0004] 2. Description of Related Art

[0005] A variety of apparel garments or items include one or more molded features. For example, brassieres include breast cups molded in a composite fabric that has a fabric layer and a foam layer. Similarly, protective products such as, but not limited to, kneepads, elbow pads, and the like include features molded in a composite fabric of fabric and foam.

[0006] In addition, a variety of non-apparel products such as, but not limited to, automotive interiors, home furnishings, and others can include such molded composite fabrics.

[0007] Typically, molded composite fabrics include a layer of thermoplastic urethane (TPU) foam adhered to a knit fabric. Unfortunately, TPU foam can be expensive and, thus, its use can be cost prohibitive in many consumer product applications. Also, TPU foams are sensitive to ultraviolet radiation present in ambient light. Specifically, ultraviolet radiation tends to cause TPU foams to yellow. In many applications, the yellowing of TPU foam is unacceptable. Therefore, many TPU foams are laminated or faced on both sides with a fabric layer to mask this yellowing. These additional facing layers can add cost and weight to the resultant product.

[0008] The selection of TPU foam and knit fabric are particularly suited for use with one another in a molded composite fabric as both the TPU foam and the knit fabric typically require high molding temperatures and lengthy molding times (e.g., 400 degrees Fahrenheit for about 60 seconds). Unfortunately, the high molding temperatures and lengthy molding times can also make the use of these composite fabrics cost prohibitive in many consumer product applications.

[0009] Accordingly, there is a continuing need for molded composite fabrics and methods of molding that overcome and/or mitigate one or more of the aforementioned and other drawbacks and deficiencies of the prior art.

BRIEF SUMMARY OF THE INVENTION

[0010] It is object of the present invention to provide a molded composite fabric having a layer of non-woven fabric and a layer of foam.

[0011] It is another object of the present invention to provide a molded composite fabric having a layer non-woven fabric laminated to both sides a layer of foam.

[0012] It is another object of the present invention to provide a method of molding a composite fabric having a layer of non-woven fabric and a layer of foam.

[0013] It is yet another object of the present invention to provide a method of manufacturing a composite fabric from a non-woven fabric and a layer of foam.

[0014] The aforementioned and other objects of the present invention are provided by a molded composite fabric. The molded composite fabric has a polyethylene foam layer and a first fabric layer adhered to a first side of the polyethylene foam layer to define a composite fabric. The molded composite fabric also includes a feature molded in the composite fabric. The first fabric layer has a non-woven fabric with a web of randomly disbursed fibers.

[0015] A brassiere is provided that includes a garment body and a pair of molded breast cups having a first fabric layer adhered to a first side of a polyethylene foam layer. The first fabric layer has a non-woven fabric with a web of randomly disbursed fibers.

[0016] A method of forming a molded non-woven fabric is also provided. The method includes selecting a non-woven fabric having a web of randomly disbursed fibers, exposing the non-woven fabric to mechanical agitation, laminating the non-woven fabric to a first side of a polyethylene foam layer to a composite fabric, compressing the composite fabric between a top mold and a bottom mold, and maintaining the composite fabric between the top and bottom molds for a predetermined dwell time.

[0017] The above-described and other features and advantages of the present invention will be appreciated and understood by those skilled in the art from the following detailed description, and drawings.

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS

[0018] FIG. 1 is a cross sectional view of an exemplary embodiment of a molded composite fabric according to the present invention;

[0019] FIG. 2 illustrates a molding step for the composite fabric of FIG. 1 during a heating portion;

[0020] FIG. 3 illustrates the molding step of FIG. 2 during a molding portion;

[0021] FIG. 4 illustrates a manufacturing process for molded composite fabrics according to the present invention;

[0022] FIG. 5 illustrates a first exemplary embodiment of a garment having a molded composite fabric in an unassembled state; and

[0023] FIG. 6 illustrates a second exemplary embodiment of a garment having a molded composite fabric in an unassembled state.

DETAILED DESCRIPTION OF THE INVENTION

[0024] Referring to the drawings and in particular to FIG. 1, a molded composite fabric according to the present invention is illustrated generally by reference numeral 10. Composite fabric 10 includes one or more fabric layers 12 adhered to a foam layer 14, where the fabric and foam layers have been molded to define a molded feature 16.

[0025] Feature 16 can be any desired feature as required by the end use of composite fabric 10. For example, composite fabric 10 can find use in a garment, such as a brassiere that requires breast cups. In this example, feature 16 can define the breast cups of the brassiere. In another example, composite fabric 10 can find use in a protective apparel item, such as a kneepad that requires shaping to approximate the shape of the protected body part. In yet another example, composite fabric 10 can find use in an insulating apparel garment, such as a coat, jacket, or sweatshirt. In this example, feature 16 can be a plurality of expanded sections. In yet another example, composite fabric 10 can find use in a decorative garment where feature 16 is provided to add a pattern or design to the garment.

[0026] It should be recognized that composite fabric 10 is described above by way of example in use as a garment. Of course, it is contemplated by the present disclosure for composite fabric 10 to find use in other non-garment applications.

[0027] Fabric layer 12 can be adhered to foam layer 14 by any known method. Preferably, fabric layer 12 is adhered to foam layer 14 by a solvent-based adhesive 18 such as, but not limited to, a web adhesive, a film adhesive, a dot adhesive, and others. Of course, it is contemplated by the present disclosure for fabric layer 12 and foam layer 14 to be adhered to one another by other methods such as, but not limited to, sonic welding. It is further contemplated by the present disclosure for fabric layer 12 and foam layer 14 to be adhered one another continuously or discontinuously across their mating surfaces.

[0028] For purposes of clarity, composite fabric 10 is described herein having fabric layer 12 adhered to one side of foam layer 14. However, it is also contemplated by the present disclosure for composite fabric 10 to have a second fabric layer (not shown) adhered to the opposite side of foam layer 14 so that the composite fabric defines a three layer structure having a middle foam layer.

[0029] Feature 16 is molded in composite fabric 10 after fabric layer 12 and foam layer 14 are adhered to one another. Advantageously, the materials of fabric layer 12 and foam layer 14 are configured for use with one another in composite fabric 10 as both can be molded at low molding temperatures and short molding times. Preferably, fabric layer 12 is made of materials that can be molded at temperatures of less than about 300 degrees Fahrenheit for about 20 seconds. Similarly, foam layer 14 is made of a material that can withstand the molding temperatures composite fabric 10 is exposed to during the molding process.

[0030] In an exemplary embodiment, fabric layer 12 is a non-woven fabric having a web of randomly disbursed fibers or filaments (hereinafter "fibers"), where the web preferably has uniform fiber orientation in all directions. It is also preferred that the fibers be bonded to and/or entangled with one another. The individual fibers can be mono-component, multi-component, or any combinations thereof.

[0031] Fabric layer 12 can be substantially inelastic or inextensible (hereinafter "rigid") or can be substantially elastic depending on the end use of composite fabric 10. In one exemplary embodiment, fabric layer 12 provides hand feel acceptable for soft fabric applications. The hand feel, as well as other physical characteristics (e.g., elasticity) of fabric layer 12 can be affected by the structure of the individual fibers, the composition of the fiber materials, the size of the individual fibers, or any combinations thereof.

[0032] For example, fabric layer 12 can include about 100% of a polymer such as, but not limited to, nylon, polypropylene, polyester, and other polymers. It is also contemplated by the present invention for at least a portion of the fibers in fabric layer 12 to be natural fibers (e.g., cotton, wool, hemp).

[0033] In another example, fabric layer 12 includes multi-component fibers having a blend of polymers such as fibers having a blend of a low-melting temperature polymer and a high-melting temperature polymer. The low-melting temperature polymer allows the non-woven fabric to be molded, while the high-melting temperature polymer introduces structural stability to the fabric. By way of example, the low-melting temperature polymer allows the non-woven fabric to be molded at temperatures of less than about 300 degrees Fahrenheit. In yet another embodiment, fabric layer 12 can include at least two different mono-component fibers. One of the mono-component fibers has a low-melting temperature polymer, while another of the mono-component fibers has a high-melting temperature polymer. In still another example, fabric layer 12 can include fibers having two or more different diameters.

[0034] Accordingly, it is contemplated by the present disclosure for fabric layer 12 to have individual fibers sized, positioned, configured, and composition of materials sufficient to provide the physical characteristics desired for composite fabric 10.

[0035] Fabric layer 12 can be produced using a non-woven process such as, but not limited to, a melt-blowing process, a spun-bonding process, a hydroentanglement process, a carding process, or any combinations thereof.

[0036] An exemplary non-woven fabric suitable for fabric layer 12 used in soft fabric applications includes EVOLON, which is commercially available from Freudenberg Nonwovens of Durham, N.C. EVOLON is made using a spunbonding and hydroentangling process. The spunbonded fibers are multi-component fibers having 70% PET and 30% NYLON. During the hydroentanglement portion of the process, the fibers are split into segments.

[0037] It has been found that the low molding temperatures afforded by the use of non-woven fabric layer 12 advantageously allows foam layer 14 to be made of foams also having a low molding temperature such as, for example, polyethylene foam. Preferably, foam layer 14 is low-density polyethylene foam. Polyethylene foam is cheaper than the TPU foams used in the prior art. In addition, polyethylene foam does not yellow or discolor when exposed to ultraviolet radiation present in ambient light and, thus, composite fabric 10 eliminates the need for facing of foam layer 14 with additional protective layers. As such, composite fabric 10 can be made lighter and less expensive than prior art faced foams.

[0038] The thickness, softness and level of stretch of foam layer 14 and/or fabric layer 12 can be selected to match the desired end-use of composite fabric 10.

[0039] Referring now to FIGS. 2 and 3, a molding step according to the present invention for feature 16 is illustrated generally by reference numeral 20. Composite fabric 10 is illustrated in FIG. 2 before the molding of feature 16 and is illustrated in FIG. 3 during the molding of the feature.

[0040] Molding step 20 includes a heating station 22 and a molding station 24. Heating station 22 can include, for example, one or more radiant heating plates for heating composite fabric 10 as it is moved past the heating station in a machine direction 26 towards molding station 24.

[0041] Heating station 22 heats composite fabric 10 so that the composite fabric is heated to a predetermined temperature. For example, heating station 22 heats composite fabric 10 to a temperature of less than about 375 degrees Fahrenheit. In a preferred embodiment, heating station 22 heats composite fabric 10 to about 300 degrees Fahrenheit.

[0042] Next, molding step 20 moves the heated composite fabric 10 to molding station 24. Molding station 24 includes a molding cavity 28 having a desired shape. In the illustrated embodiment, molding cavity 28 has a shape for forming a breast cup for a brassiere. Preferably, molding station 24 is a vacuum molding station that draws the heated composite fabric 10 into cavity 28 in a molding direction 30. Molding station 24 maintains composite fabric 10 in cavity 28 for a predetermined dwell time. For example, molding station 24 maintains composite fabric 10 in cavity 28 for less than about 30 seconds. In a preferred embodiment, molding station 24 maintains composite fabric 10 in cavity 28 for about 20 seconds.

[0043] Advantageously, the predetermined temperature and dwell time of molding step 20 (e.g., 300 degrees Fahrenheit for about 20 seconds) are less than those currently used in the manufacture of composites having TPU foam and knit fabric (e.g., 400 degrees Fahrenheit for about 120 seconds). Thus, molding step 20 can form composite fabric 10 into the desired shape faster and more economically than prior processes.

[0044] Referring now to FIG. 4, a manufacturing process according to the present invention for making composite fabric 10 is illustrated generally by reference numeral 40. In addition to molding step 20 described above, manufacturing process 40 includes a washing or agitation step 42 and a lamination step 44. During process 40, fabric layer 12 is first exposed to agitation step 42, then the fabric layer and foam layer 14 are adhered to one another during lamination step 44 to define composite fabric 10, and finally the composite fabric is molded during molding step 20.

[0045] Preferably, agitation step 42 exposes the desired non-woven fabric 12 to mechanical agitation, more preferably in the presence of a wetting agent such as, but not limited to, water and/or fabric softener. For example, it is contemplated for agitation step 42 to be carried out in a typical household washing machine or a typical industrial dyeing process (processed with or with out dyes). In this manner, agitation step 42 subjects fabric layer 12 to agitation in the presence of the wetting agent to permit the individual fibers of the non-woven fabric to achieve a desired position with respect to each other as discussed immediately below.

[0046] While not wishing to be bound by a particular theory, it is believed that agitation step 42 introduces an element of freedom to the individual fibers of the non-woven fabric 12. It is believed that this freedom allows the fibers to move and/or slide with respect to one another to mitigate tearing of the fabric during subsequent lamination and molding steps. For example, it is believed that the agitation of agitation step 42 weakens and/or breaks at least some of the bonds and/or entanglements between the individual fibers of the non-woven fabric 12.

[0047] In a preferred embodiment of agitation step 42, the agitation step includes the use of fabric softener as the wetting agent. While not wishing to be bound by a particular theory, it is believed that the fabric softener provides a degree of lubrication to the individual fibers of the non-woven fabric. It is believed that the lubrication of the individual fibers allows the fibers to slide with respect to one another.

[0048] After agitation step 42, fabric layer 12 and foam layer 14 are adhered to one another in lamination step 44. During lamination step 44, fabric layer 12 is adhered to foam layer 14 by, for example, applying an adhesive to the fabric and/or foam layers and compressing the layers together to define composite fabric 10.

[0049] In some embodiments of the present invention, manufacturing process 40 can include a perforating step 46 before lamination step 44. Many of the low molding temperature foams available for use as foam layer 14 (e.g., low-density polyethylene foam) are closed cell foams. Thus, it is contemplated by the present invention for manufacturing process 40 to include perforating step 46 to induce a predetermined level of permeability and/or breathability to foam layer 14. In a preferred embodiment, perforating step 46 removes material from foam layer 14 to provide the desired permeability. For example, perforating step 46 can punch a plurality of holes through foam layer 14.

[0050] After defining composite fabric 10 at lamination step 44, manufacturing process 40 exposes the composite fabric to molding process 20 to define one or more molded features 16 in the composite fabric.

[0051] It should be recognized that process 40 is described above having lamination step 44 before molding step 20. However, it is also contemplated by the present disclosure for the lamination and molding steps to occur simultaneously with one another.

[0052] Advantageously, the composite fabric of the present invention overcomes the expense and weight associated with prior art molded composite fabrics. For example, molded composite fabric 10 can be used in the formation of a brassiere 50 as illustrated in FIG. 5. Brassiere 50 includes a garment body 52 and a pair of breast cups 54. Garment body 52 includes only non-woven fabric layer 12, while breast cups 54 include both the non-woven fabric layer and foam layer 14. Thus, brassiere 50 includes composite fabric 10 only in the areas of the breast cups, which are molded to a desired cup depth. Brassiere 50 can be configured so that foam layer 14 of breast cups 54 is in contact with the user when worn as shown. Alternately, brassiere 50 can be configured so that fabric layer 12 of breast cups 54 is in contact with the user when worn.

[0053] An alternate exemplary embodiment of a brassiere 60 having molded composite fabric 10 is illustrated in FIG. 6. Brassiere 60 includes a garment body 62 and a pair of molded breast cup inserts 64. Garment body 62 can be one or more layers of woven and/or non-woven fabrics. Inserts 64 are formed from composite fabric 10 and, thus, include both non-woven fabric layer 12 and foam layer 14. Inserts 64 can be secured to garment body 62 using any known method such as, but not limited to, sewn seams, adhesives, welds, and others. Preferably, inserts 64 are secured to garment body 62 so that foam layer 14 is in contact with the garment body and fabric layer 12 is in contact with the user when worn as shown in FIG. 6. Alternately, inserts 64 can be secured to garment body 62 so that fabric layer 12 is in contact with the garment body and foam layer 14 is in contact with the user when worn.

[0054] It should also be noted that the terms "first", "second", "third", "upper", "lower", and the like may be used herein to modify various elements. These modifiers do not imply a spatial, sequential, or hierarchical order to the modified elements unless specifically stated.

[0055] While the present disclosure has been described with reference to one or more exemplary embodiments, it will be understood by those skilled in the art that various changes may be made and equivalents may be substituted for elements thereof without departing from the scope of the present disclosure. In addition, many modifications may be made to adapt a particular situation or material to the teachings of the disclosure without departing from the scope thereof. Therefore, it is intended that the present disclosure not be limited to the particular embodiment(s) disclosed as the best mode contemplated, but that the disclosure will include all embodiments falling within the scope of the appended claims.

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