WO2012166624A1

WO2012166624A1 - Fabric assembly including leather substrate

Info

Publication number: WO2012166624A1
Application number: PCT/US2012/039643
Authority: WO
Inventors: Young-Hwa Kim; Young-Kwon Kim
Original assignee: Higher Dimension Materials, Inc.
Priority date: 2011-05-27
Filing date: 2012-05-25
Publication date: 2012-12-06

Abstract

In some aspects, the disclosure relates to composite fabric assembly comprising a leather substrate including a top surface; a woven, nonwoven, or knitted fabric substrate including a top surface and a bottom surface; and a plurality of cured polymer plates attached to the top surface of the fabric, wherein the plates are separated by gaps between directly adjacent plates on the top surface of the fabric substrate, wherein the bottom surface of the fabric is attached to the top surface of the leather substrate.

Description

FABRIC ASSEMBLY INCLUDING LEATHER SUBSTRATE

TECHNICAL FIELD

[0001] In some examples, the disclosure relates to products including leather substrates.

BACKGROUND

[0002] None.

SUMMARY

[0003] In general, the disclosure relates to fabric assemblies including leather substrates. In some examples, the assembly may include a leather substrate and a fabric layer attached to a surface of the leather substrate, e.g., via an adhesive layer. A plurality of cured polymer plates separated by gaps may be provided on the surface of the fabric layer opposite that of the leather layer. In some examples, fabric and/or cured polymer plates may improve properties of the leather substrate, such as, e.g., cut and abrasion resistance.

[0004] In some examples, the disclosure relates to a leather substrate including a top surface; a woven, nonwoven, or knitted fabric substrate including a top surface and a bottom surface; and a plurality of cured polymer plates attached to the top surface of the fabric, wherein the plates are separated by gaps between directly adjacent plates on the top surface of the fabric substrate, wherein the bottom surface of the fabric is attached to the top surface of the leather substrate.

[0005] In some examples, the disclosure relates to a method of making a fabric assembly, the method comprising attaching a bottom surface of a fabric to a top surface of a leather substrate, wherein the fabric includes a woven, nonwoven, or knitted fabric substrate including the top surface and a bottom surface, wherein the fabric includes a plurality of cured polymer plates attached to the top surface of the fabric, wherein the plates are separated by gaps between directly adjacent plates on the top surface of the fabric substrate.

[0006] The details of one or more embodiments of the invention are set forth in the accompanying drawings and the description below. Other features, objects, and advantages of the invention will be apparent from the description and drawings, and from the claims.

BRIEF DESCRIPTION OF THE DRAWINGS

[0007] FIG. 1 is a conceptual diagram illustrating an example fabric assembly in accordance with an example of the disclosure.

[0008] FIG. 2 is a diagram illustrating a plan view of an example fabric assembly in accordance with an example of the disclosure where the gaps between the guard plates are more clearly illustrated.

[0009] FIGS. 3A-C are a series of photos illustrating the removal of oil deposited on the surface of a leather substrate.

[0010] FIGS. 4A-C are a series of photos illustrating the removal oil deposited on the surface of a fabric assembly in accordance with an example of the disclosure.

DETAILED DESCRIPTION

[0011] As described above, in some examples, the disclosure relates to fabric assemblies including leather substrates. In some examples, the assembly may include a leather substrate and a fabric layer attached to a surface of the leather substrate, e.g., via an adhesive layer. A plurality of cured polymer plates separated by gaps may be provided on the surface of the fabric layer opposite that of the leather layer. In some examples, fabric and/or cured polymer plates may improve properties of the leather substrate, such as, e.g., cut and/or abrasion resistance.

[0012] Even though leather has been in use for a very long time and is still commonly used for footwear, handbags, luggage and furniture, it can be easily scuffed, cut or stained. The disclosure describes how leather can be protected by applying small cured polymer plates to the surface of the leather. In particular, small thermosetting or thermoplastic resin plates applied to the surface may greatly improve abrasion and cut resistance of the leather substrate. If the plates are printed directly onto the leather surface, however, the plates may not attach well to the leather substrate and may be easily removed. It has been determined that by first applying the resin to a fabric surface, curing the resin to form cured resin plates on the surface of the fabric substrate, and then laminating the resulting fabric substrate with cured polymer plates to the surface of the leather, the plate may be securely attached to the leather substrate via the farbic. In other examples, the fabric may first be attached to the surface of the leather, followed by the formation of the cured polymer plates on the surface of the fabric.

[0013] In this manner, an assembly is obtained that includes the leather substrate with one surface attached to an array of cured polymer plates that are held together by the fabric substrate. Using such an assembly, in some examples, leather products be can used in traditional roles, such as in footwear, while making them more attractive, giving them interesting colors and making the resulting surface resistant to cuts and abrasion. Another advantage of this disclosure, in some examples, may be the ability to use more of the leather surface since cosmetic defects (scars, etc.) in the leather are not visible in the final construction.

[0014] FIG. 1 is a conceptual diagram illustrating an example fabric assembly 100. Fabric assembly 100 may be used to form all or portions of footwear or other apparel. For example, the fabric assembly 100 may be used as the upper outer portion of a shoe or boot, or on the boot shaft in boots. As another example, the fabric assembly 100 may also be used to cover elbows or knees to provide abrasion resistance with the cushioning of leather. As another example, the fabric assembly 100 may be advantageously used in handbags and luggage to provide a protective and decorative exterior and a high quality soft leather interior.

[0015] As shown, assembly 100 includes a plurality of discrete guard plates 102 on the top surface of fabric substrate 108. Fabric 108 may be a woven, non- woven, and/or knitted fabric. As shown, guard plates 102 protrude above the surface of the fabric 108 by a height 106 and have an overall thickness 107 (penetration depth plus protrusion height). In the example shown, plates 102 partially penetrate 105 into fabric 108.

[0016] Fabric 108 is attached to the surface of leather substrate 101. Leather substrate 101 may be formed of artificial leather or real leather (e.g., leather made from animal hide such as cowhide). In some examples, artificial leather may be made of various plastic materials such as polyurethane and PVC. Artificial leather may include those leathers referred to as "leatherette", "faux leather", "patent leather", "Naugahyde", and "pleather." One example, leather substrate 101 may include artificial leathers referred to as "amara" and "clarino" which are supplied by Kuraray America, Clorino Division, New York, New York, 10022.

[0017] Leather substrate 101 may be attached to fabric 108 using any suitable technique, including those techniques used in the footwear industry. In some examples, leather substrate 101 may be attached to fabric 108 via an adhesive layer 104. Adhesive layer 104 may be formed of any suitable material for adhering (e.g., laminating) fabric 108 to leather substrate 101. In some examples, adhesive layer 104 may be hot-melt adhesive such as, e.g., those sold by Keuchel

Associates, Inc., Ohio under the name of Spunfab®. For applications using a hot melt adhesive, fabric 108 and leather substrate 101, with adhesive between the two layers, may be passed though through a laminating apparatus that applies pressure and heat to melt the adhesive. A suitable lamination machine for laminating fabric 108 to leather 102 may include lamination machines sold by Reliant Machine, Ltd., Bedfordshire, UK.

[0018] The lamination process may be performed with or without plates 102 applied to fabric 108. In some examples, plates 102 may be applied to surface of fabric 108 after fabric 108 is laminated to leather substrate 101, e.g., in cases in which the lamination temperature may be greater than the heat curing temperature of the polymer material of plates 102. In other examples, plates 102 may be applied to surface of fabric 108 before fabric 108 is laminated to leather substrate 101, e.g., in cases in which the melt temperature of the adhesive is less than the heat cure temperature of plates 102.

[0019] Other adhesive systems could also be used to attach leather substrate 101 to fabric 108 including those used in the footwear industry. Additionally or alternatively, leather substrate 101 may be mechanically attached to fabric 108. For example, leather substrate 101 may be attached to fabric 108 using one or more rivets extending through both leather 101 and fabric 108. As another example, leather substrate 101 may be attached to fabric 108 by sewing leather substrate 101 to fabric 108.

[0020] In some examples of the disclosure, advanced fabric material for forming the top portion (fabric 108 plus plates 102) of assembly 100 may include

SuperFabric®. SuperFabric® (commercially available from Higher Dimension Materials, Oakdale, MN) may be a family of fabric assemblies with a variety of unique features. In some examples, SuperFabric® may comprise a woven or non- woven base fabric material, e.g., fabric 108, onto which cured polymer guard plates, e.g., plates 102, have been attached, e.g., due to the partial penetration of the guard plates into the surface of the substrate before being fully cured.

Examples of articles including a woven or non-woven base fabric material may include one or more examples described in United States Patent No. 6,962,739, entitled "Supple Penetration Resistant Fabric and Method of Making;" United States Patent No. 7,018,692, entitled "Penetration Resistant Fabric with Multiple Layer Guard Plate Assemblies and Method of Making the Same;" published United States Patent Application No. 2004/0192133, entitled "Abrasion and Heat Resistant Fabrics;" and published United States Patent Application No.

2009/014253, entitled "Supple Penetration Resistant Fabric and Method of Making."

[0021] In some examples, SuperFabric® can be fabricated to resist water penetration, oil and other stains and remain flexible and breathable. SuperFabric® may greatly increases the wear resistance properties of the base fabric as measured by Taber Abrasion testing (ASTM 3884). For example, SuperFabric® fabric assemblies provide increased abrasion resistance, as determined by the number of cycles in the Taber Abrasion test, by factors ranging from 2 to over 12 times.

[0022] Example fabric types for fabric 108 may include, but are not limited to, woven, non- woven, or knit fabrics having the ability to permit at least partial penetration of uncured resin used to form polymeric guard plates 102 after deposition of the uncured polymer on fabric substrate. Fabric materials include without limitations cotton and cotton-polyester blends and other natural and man- made fabrics having similar properties. In one example, the flexible fabric substrate may include a tightly woven cotton-polyester blend. In such an example, this type of fabric may be used because resin compositions including heat-cured epoxy resins used to form guard plates have been found to seep into and bond well with this substrate fabric.

[0023] As noted above, in some example, plates 102 may be arranged to provided contiguous, connected gap regions over the surface of base fabric. Plates 102 may range in size and shape, and in overall geometrical arrangement, and guard plates 102 may be identical to one another, or may be made of identical groupings of plates 102. Plates 102 may be arranged in a regular geometric pattern on surface of base fabric 108. Plates 102 may also differ from one another and be arranged in a random pattern on the surface of fabric 108. Plates 102 may partially penetrate into the fabric to ensure good adhesion between plates 102 and fabric 108. Plate dimensions in the plane parallel to the surface plane of fabric 108 may range from about 30 mils to 150 mils, such as, e.g., about 50 mils to 150 mils. In some examples, plates 102 may protrude above the surface of the fabric 108 to a height 106 ranging from about 5 to 40 mils, such as, e.g., about 5 to 20 mils. Protrusion of plate 108 may be less than the largest dimension of plate 102 in a plane parallel to the top surface of fabric 108. Gap widths 103 between adjacent plates 102 may range from about 5 mils to 100 mils, such as, e.g., about 5 mils to 40 mils, about 5 mils to 25 mils, or about 5 mils to 15 mils. Dimesions outside the exemplary ranges described herein are also contemplated. Without loss of generality, assembly 100 may have plates 102 with gap widths that are not uniform over the entire assembly 100 to allow assembly 100 to conform to the curved surfaces, which may be beneficial depending on the application of assembly 100.

[0024] In some examples, cured resin plates 102 may be constructed of a variety of composite materials, such as cured epoxies, polyurethanes, hybrid of cured epoxy- polyurethane, etc. composited with wear and strength enhancing materials such as silicon dioxide, aluminum oxide, titanium oxide and other filler materials such as pigments.

[0025] Suitable polymeric compositions for forming plates 102 may include epoxy resin(s). In one embodiment, plates 102 may be formed of heat-cured epoxy resin. Another example of an appropriate resin may be ultra-violet (UV) cured acrylate. Depending on the particular application, plates 102 may have a hardness between about 70 and about 100 Shore D, such as, e.g., between about 80 and about 95 Shore D. The hardness of plates 102 may depend on a number of factors including, but not limited to, the polymeric resin composition used to form the plates and/or the process used to cure the polymeric resin composition after being deposited on the surface of fabric 108. In some embodiments the guard plates may comprise a thermoset epoxy. In some embodiments the guard plates may comprise inorganic filler particles. Thermally cured polymeric materials used for guard plates may be relatively hard and crack-resistant.

[0026] In some example, the polymer resin selected for use to form plates 102 may ensure a strong bond between the plate and the fabric 108. In some examples, a suitable polymer resin for construction of guard plates is a one -part heat-curable epoxy resin formulated to (i) provide abrasion resistance, (ii) be screen printable, (iii) be resistant to fracture, (iv) be bondable to the base material, and (v) have good shape definition during printing and curing of the guard plate material. Such resins may be readily formulated to meet these criteria and are available from, for example, Fielco Industries, Inc., Huntingdon Valley, PA, 19006, which has formulated resins that may meet the characteristics set forth in this paragraph and has given them the designations: TR21 and TR84. Other examples of suitable resin formulations are available from Hexion Specialty Chemicals, Columbus, OH 43215. For example, Hexion Starting Formulation 4019 may be a suitable thermosetting heat curable epoxy base resin formulation. In some examples, abrasion resistance provided by guard plates can be increased by adding small particles (e.g., 1 to 100 micrometers) of silica, alumina, silicon carbide, titanium oxide and the like to the resin.

[0027] In some embodiments, the use of low-wicking resin compositions to form guard plates 102. In some examples, a low-wicking polymeric resin composition may include one or more of an epoxy resin, phenolic resin, e.g., bakelite, polyester resin, polyurethane resin, polyimide resin, allyl resin, and the like. The polymeric resin may be a polymeric resin that irreversibly cross-links via a secondary process, such as, e.g., a thermal and/or UV process. In some examples, the polymeric resin formulation may include thermosetting resins and/or resins such as acrlyates, arylate copolymers, styrenes, and hybrids. Example epoxy resins may include Epon 828, a di-functional glycidyl ether based on bisphenol A, (obtained from Hexion Corporation, Columbus, OH), Epon 161, which is multi-functional gylcidyl epoxy of a novolac oligomer (also available from Hexion), and/or Epon 160, which is a higher molecular weight analog of Epon 161(also available from Hexion). [0028] In some examples, the resin composition may include one or more additives. Additives may include one or more suitable curing agents, rheology modifiers, such as, e.g., one or more thixotropes, surfactants, dispersants, diluents, air release agents, fillers, colorants (dyes), glass beads, and/or the like. In some examples, a rheological modifier may impart yield stress on the resin composition, and may cause the resin composition to exhibit gel-like properties. In some examples, the resin composition may include one or more appropriate rheological modifiers from available from Hexion Corp, Columbus, OH 43215, such as, e.g., Heloxy Modifier 67. In some examples, the resin composition may include BYK 525, 555, which are bubble releasing materials from BYK USA, Wallingford, CT; BYK-9010, which is a wetting/dispersing aid also from BYK; and/or A- 187, which is an epoxy functional silane available from GE Silicones. Examples colorants may include Ti0₂, burnt umber, FD&C blue #2, cardinal pthalo blue, and BK 5099. In some examples, appropriate fillers may be included in the resin composition, such as, e.g., Imsil A30 available from Unimin Specialty Minerals, Inc, New Canaan, CT 06840.

[0029] FIG. 2 is a diagram illustrating a magnified view of top surface 200 of an example of assembly 100 (FIG. 1). As shown, discrete cured polymer plates 202 are arranged in a pattern with gap regions around each discrete guard plate providing a multiplicity of continuous gaps 203 between the plates. As represented by paths 203, the continuous gaps may be formed between guard plates 202 in a straight line and/or in any zigzag pattern along the gap regions.

[0030] EXAMPLE

[0031] To illustrate that fabric assemblies (such as assembly 100) increase cut and abrasion resistance beyond that of the original leather substrate by itself, two sample construction where made and tested. In particular, a sample construction was made by laminating a fabric with printed cured polymer plates on one surface to a sheet of leather. Three sample constructions were made. The first sample (Sample A) included a 100D crepe polyester base fabric (about 41 mils thick) with an hexagonal pattern of guard plates attached laminated onto an artificial leather about 41 mils thick with Spunfab® hot melt adhesive. The plate features were about 70 mils wide with about 25 mils gaps and a protrusion of about 22 mils out of the base fabric. The second sample (Sample B) included a 100D crepe polyester base fabric (about 41 mils thick) with a penta pattern of plates laminated onto an artificial leather about 41 mils thick with Spunfab® hot melt adhesive. The largest plate feature was about 80 mils wide with about 15 mils gaps and a protrusion of about 18 mils out of the base fabric. The third sample (Sample C) included a 100D crepe polyester base fabric (about 41 mils thick) with a penta pattern of guard plates laminated onto an artificial leather about 41 mils thick with Spunfab® hot melt adhesive. The largest plate feature was about 67 mils wide with about 10 mils gaps and a protrusion of about 18 mils out of the base fabric.

[0032] During testing, the leather by itself was found to have a cut resistance ranging from 1 to 1.5 pounds in a test where a new razor blade is passed over the surface with an applied weight. In this test, the weight at which a through cut is obtained is noted. For the three samples assemblies including cured polymer plates on one surface of a fabric laminated to a leather surface, a cut resistance ranges from 6 to 13 pounds was found, depending on the coating weight and thickness of the cured polymer plates and fabric.

[0033] In addition, the protected leather was found to be more abrasion resistant and puncture resistant compared to that of the leather by itself. For example, while unprotected leather abrades was found to abrade very quickly, leather attached to fabric with a plurality of cured polymer plates was found, in some examples, to withstand more than 3000 cycles on a Tabor Abrader. The tensile strength of leather was also found to be improved with the incorporation of fabric including cured polymer plates, as evidenced by its resistance to tearing. Results from the testing are shown in Tables I and II.

[0034] Table I. Mechanical Pro erties of Various Protected Leather Sam les

[0035] Table II. Puncture erformance of Protected and Un rotected Leather

[0036] In some example, the protected leather (leather attached to fabric including a plurality of cured polymer plates) was also found to be less susceptible to staining. For example, an application of oil was applied to unprotected leather and it could not be removed by cleaning. In comparison, oil applied to the Micro Armor material was removed by rinsing. As can be seen in FIGA. 3A-C, starting with a clean leather substrate (FIG. 3A), an oil drop was deposited onto the surface (FIG. 3B). It was found that the oil drop was absorbed into the leather and could not be rinsed off (FIG. 3C). In comparison, starting with a clean leather substrate attached to a fabric including a plurality of cured polymer plates (FIG. 4A), a drop of the same oil was deposited onto the surface of the fabric/plates (FIG. 4B). It was found that the protected surface could easily be rinsed clean of the oil (FIG. 4C).

[0037] Various embodiments of the invention have been described. These and other embodiments are within the scope of the following claims.

Claims

CLAIMS:

1. A composite fabric assembly comprising:

a leather substrate including a top surface;

a woven, nonwoven, or knitted fabric substrate including a top surface and a bottom surface; and

a plurality of cured polymer plates attached to the top surface of the fabric, wherein the plates are separated by gaps between directly adjacent plates on the top surface of the fabric substrate,

wherein the bottom surface of the fabric is attached to the top surface of the leather substrate.

2. The assembly of claim 1, wherein the plates protrude out of the top surface of the fabric substrate to define a thickness between approximately 5 mils and approximately 1 millimeter.

3. The assembly of claim 2, wherein the plates protrude out of the top surface of the fabric substrate to define a thickness between approximately 5 mils and approximately 40 mils.

4. The assembly of claim 1, wherein the cured polymer plates comprise a cured polymer resin partially penetrating into the surface of the fabric substrate to a depth less than a thickness of the woven fabric substrate to provide a mechanical bond between the fabric substrate and the guard plates.

5. The assembly of claim 1, wherein the gaps between plates have a substantially uniform width.

6. The assembly of claim 1, wherein the width of the gaps is between 5 and 25 mils.

7. The assembly of claim 1, wherein the fabric substrate is selected from the group consisting of polyester, nylon, cotton, aramid, polyethylene, or blends thereof.

8. The assembly of claim 1, wherein the plurality of plates are arrayed in a pattern such that a plurality of continuous gaps are defined between adjacent plates.

9. The assembly of claim 1, further comprising a hot melt adhesive between the bottom surface of the fabric substrate and top surface of the leather substrate, wherein the bottom surface of the fabric substrate and top surface of the leather sheet substrate are attached to each other via the hot melt adhesive.

10. The assembly of claim 1, wherein the leather substrate comprises one of an artificial leather sheet or a cowhide leather.

11. A method of making a fabric assembly, the method comprising attaching a bottom surface of a fabric to a top surface of a leather substrate, wherein the fabric includes a woven, nonwoven, or knitted fabric substrate including the top surface and a bottom surface, wherein the fabric includes a plurality of cured polymer plates attached to the top surface of the fabric, wherein the plates are separated by gaps between directly adjacent plates on the top surface of the fabric substrate.

12. The method of claim 11 , wherein the plates protrude out of the top surface of the fabric substrate to define a thickness between approximately 5 mils and approximately 1 millimeter.

13. The method of claim 12, wherein the plates protrude out of the top surface of the fabric substrate to define a thickness between approximately 5 mils and approximately 40 mils.

14. The method of claim 11 , wherein the cured polymer plates comprise a cured polymer resin partially penetrating into the surface of the fabric substrate to a depth less than a thickness of the woven fabric substrate to provide a mechanical bond between the fabric substrate and the guard plates.

15. The method of claim 11, wherein the gaps between plates have a substantially uniform width.

16. The method of claim 11, wherein the width of the gaps is between 5 and 25 mils.

17. The method of claim 11, wherein the fabric substrate is selected from the group consisting of polyester, nylon, cotton, aramid, polyethylene, or blends thereof.

18. The method of claim 11 , wherein the plurality of plates are arrayed in a pattern such that a plurality of continuous gaps are defined between adjacent plates.

19. The method of claim 11, further comprising a hot melt adhesive between the bottom surface of the fabric substrate and top surface of the leather substrate, wherein the bottom surface of the fabric substrate and top surface of the leather sheet substrate are attached to each other via the hot melt adhesive.

20. The method of claim 11, wherein the leather substrate comprises one of an artificial leather sheet or a cowhide leather.

21. The method of claim 11 , further comprising depositing the plurality of cured polymer plates on the top surface of the fabric.

22. The method of claim 21 , wherein the plurality of cured polymer plates are deposited on the top surface of the fabric prior to attaching the fabric to the leather substrate.