Patent Application
20140170389
The present invention relates to three-dimensional (“3D”) fabrics. More particularly, the invention relates to multi-layered fabrics having a traditional fabric outer layer; and a dimensional layer formed of polymer foam, wherein the dimensional layer provides a variable physical depth to the fabric.
Camouflage suits for bow-hunting deer typically are made with fabrics having printed patterns intended to blend in with colors and patterns in the hunter's background. More elaborate camouflage suits, such as the ghillie suit, are also available. There is a need for improved camouflage suits that blend into the background. The materials and methods developed for camouflage suits have broad applicability in other areas as well.
Materials and methods for 3D fabrics are disclosed. The 3D fabrics have multiple layers including an outer layer of traditional fabric and a dimensional layer integrated with outer layer. The 3D fabrics have variable depth, typically ranging from between about 0.25 inches to about 2.0 inches. The 3D fabrics are produced from a molding process that creates the dimensional layer while adhering it to the outer layer. The 3D fabrics have unique visual properties which make them desirable for a variety of applications.
The accompanying drawings, which are incorporated into and constitute a part of this specification, illustrate one or more embodiments of the present invention and, together with the detailed description, serve to explain the principles and implementations of the invention.
In the drawings:
Embodiments of the present invention are described herein in the context of compositions of three dimensional (3D) fabrics and methods for making 3D fabrics and articles using 3D fabrics. Those of ordinary skill in the art will realize that the following detailed description of the present invention is illustrative only and is not intended to be in any way limiting. Other embodiments of the present invention will readily suggest themselves to such skilled persons having the benefit of this disclosure. Reference will now be made in detail to implementations of the present invention as illustrated in the accompanying drawings. The same reference indicators will be used throughout the drawings and the following detailed description to refer to the same or like parts.
In the interest of clarity, not all of the routine features of the implementations described herein are shown and described. It will, of course, be appreciated that in the development of any such actual implementation, numerous implementation-specific decisions must be made in order to achieve the developer's specific goals, such as compliance with application- and business-related constraints, and that these specific goals will vary from one implementation to another and from one developer to another. Moreover, it will be appreciated that such a development effort might be complex and time-consuming, but would nevertheless be a routine undertaking of engineering for those of ordinary skill in the art having the benefit of this disclosure.
“Traditional fabrics” are essentially flat, single layer materials such as cotton cloth, wool cloth, synthetic or synthetic blend cloth, and felt. While these fabrics have a dimension of thickness or depth, the thickness is typically small (less than about 3 mm) and uniform.
“Three dimensional fabric” of “3D fabric” refers to a multilayer fabric having an outer fabric layer and a dimensional layer that gives the fabric variable physical depth, where the outer layer is integrally bonded to the dimensional layer.
It is within the invention to produce molds and fabrics intermediate and in combination between those embodiments depicted in
In both embodiments, the outer fabric layer 8 or 28 is preferably colored or patterned on the outer surface side. The optional inner fabric layer 12 or 32 is typically not visible when the 3D fabric 5 or 26 is incorporated into an article of clothing.
The dimensional layer 10 or 30 comprises a flexible, open-cell polyurethane foam with a preferred density between about 2.0 and 4.0 pounds/cubic foot, and more preferably a density between about 2.8 and 3.4 pounds/cubic foot. The foam is formed by a polymerization reaction between an isocyanate component and a polyol component that are mixed immediately prior to molding. Mixing the components produces a viscous dense liquid, which will be referred to herein as the “foam mixture.” As the polymerization reaction progresses, gases are produced which form the cells in the foam and results in an increase in volume of the mixture. The “rise time” is the period of volume expansion. In the context of the present invention, the two parts of the mold must be positioned during the rise time, thereby confining the dimensional layer before the end of the rise time.
The properties of the foam mixture dictate certain aspects of the manufacturing process.
Because of the density and viscosity of the foam mixture, it is presently preferable that the foam mixture be applied to the top of the outer fabric layer. This can be done manually, though mixing of the components of the foam mixture and application of the foam mixture over the outer fabric layer are preferably done by machine. A variety of mixing heads are presently available to mix the components. Specialty automated processes and robots may be designed to apply the foam mixture in desired amounts at particular points depending on the desired product. If the dimensional layer is to be of uniform thickness as in
Though it is presently preferred to produce the 3D fabrics by applying the foam mixture to the bottom of the outer fabric layer, it is also possible to produce the fabrics by applying the foam mixture to the top of an inner fabric layer and then apply the outer fabric layer over the foam mixture, allowing the foam mixture to rise to fit the contours of a contoured upper mold. Further, it is possible to produce the 3D fabrics in an arrangement where the inner and outer fabric layers are vertical and the foam mixture is applied between them in a continuous process.
Manufacture of 3D fabrics may be done by producing individual sheets having defined sizes using substantially planar fixed molds as depicted in
Manufacture of the 3D fabric 5 or 26 may also be performed in a continuous process, as shown in
Referring to
It is essential to the invention that the outer fabric layer 8 and the dimensional layer 10 are integrally bonded to each other. If an inner fabric layer 12 is present, the inner fabric layer 12 is also preferably integrally bonded with the dimensional layer 10. In a presently preferred embodiment, such bonding is achieved by the molding process. The outer fabric layer 8 is preferably breathable and porous, allowing adhesion of the fabric layer and foam mixture before the foam mixture sets. When the resin sets and forms the dimensional layer, it also binds the dimensional layer 10 to the outer fabric layer 8. The dimensional layer 10 is preferably an open-cell foam. Polyurethane at a density of about three pounds per cubic foot is a preferable material for its lightness, washability, breathability, and durability.
Bleeding and staining are two potential problems in the manufacturing of the 3D fabrics of the invention. Bleeding results in the foam mixture penetrating the outer layer before the polymerization reaction is complete, and results in visible foam on the outer surface of the fabric. Staining is less obvious than bleeding, but results in discoloration of the outer fabric layer. Several variables may affect these problems. The variables include: 1. type of fabric (cotton, polyester, blend, etc.); 2. Porosity of fabric (woven vs. knit, tightness of weave or knit, thread count, etc. . . . ); 3. Fabric treatments (waterproofing, starch, etc. . . . ); 4. type of foam mixture; 5. amount of foam mixture; 6. timing and temperature during molding; 7. pressure on foam during molding; and 8. use of catalysts or other chemical additives in the foam mixture. As described in the examples, tests have been carried out to determine the effects of these variables.
Based upon the test results described in the examples, fabrics may be placed in one of several categories. “High porosity” fabrics are those having significant bleed-through during the molding process with no pressure exerted by an upper mold portion. “Medium porosity” fabrics are those means having no significant bleed-through with no pressure, but significant bleed-through under low pressure. “Low porosity” fabrics are those having no significant bleed-through during the molding process under low pressure. “Impermeable” fabrics are those that have no significant bleed-through under high pressure. Though high porosity and medium porosity fabrics are useful for some applications of the invention, for applications where the prevention of bleed-through is important as well as breathability, the most preferred fabrics are low porosity fabrics including: tightly-woven synthetic microfibers, tightly-knit synthetic microfibers, tightly-woven natural microfibers, tightly-knit natural microfibers, and tightly-woven cotton/polyester blends with a thread count above 150. Such preferences apply to both the inner fabric layer and the outer fabric layer. Specifically preferred fabrics for the outer layer include Amerisuede 2-bar 100% polyester with a warped knit and brushed face and a weight of 220 grams per square meter, Amerisuede 3-bar 100% polyester with a warped knit and brushed face and a weight of 280 grams per square meter and 100% polyester knit fleece.
During the rise time, the pressure exerted by the mold portions against the polyurethane is dependent upon a number of factors. Though it is possible to control the mold portions to a set pressure point, in practice it is preferable to rigidly fix the distance between the mold portions. In such an arrangement, the pressure exerted against the mold portions by expansion of the foam mixture during the rise time is dependent upon the amount of foam mixture applied and the reaction conditions. It is presently preferred that foam mixture be applied in amount so the that the reaction conditions result in a pressure against the mold portions during the rise time between about 0.02 psi and 0.10 psi, and more preferably between about 0.03 psi and 0.06 psi. Selection and application of the foam mixture must also result in a dimensional layer of the desired density.
Presently preferred polyurethanes include 3 lb. FlexFoam-iT!® by Smooth-On.
The molding process can be carried out in a variety of ways, depending on the requirements of the application. The basic requirements are: (1) a dimension portion of the compression mold; (2) a second portion of the compression mold, which may be flat as in
Silicon molds may be used low volume applications of the manufacturing process. For high volume applications, especially where temperature control is critical, molds made of metals such as aluminum are preferable.
The 3D fabrics of the invention are easily sewable using conventional equipment, as the dimensional layer is compressible during the sewing process. However, in some applications where thick dimensional layers are desired in portions of the fabric, it may be desirable to design and manufacture the fabric to have thinner areas of the dimensional layer in accordance with specific patterns. In some cases, the 3D fabric may include areas without the dimensional layer for application-specific needs.
The 3D fabrics of the invention have a wide variety of applications. They may be used for camouflage hunting apparel. They may be used for military camouflage apparel. They may be used for producing ordinary apparel (such as coats, pants, hats, shoes, etc.) with interesting visual effects. They may be used for producing ordinary apparel for their insulating properties. They may be used for furniture coverings. They may be used in wall coverings. They may be used in set designs. Specialty outer and inner fabric layers may be incorporated for properties such as sonic insulation, thermal insulation, heat retention, heat reflectivity, indetectability to remote sensors (radar, sonar, infra-red detectors, and the like). Electronics may be molded into the dimensional layer for purposes of communication, monitoring of body functions, lighting and the like). Other applications of the fabrics will also become apparent over time.
The present invention includes materials and methods to produce unique wearable three-dimensional (3-D) fabrics 5. The fabrics 5 comprise an optional inner fabric layer 12, a dimensional layer 10 made of breathable foam, and a patterned outer layer 8. The dimensional layer 10 may be molded to have contours matching the pattern of the outer layer 8, with the resulting multilayer fabric 5 or 26 having both physical and graphical depth.
One application of this technology is to create camouflaged clothing articles. For example, a suit comprising a jacket and pants may have a tree or woods motif, where the dimensional layer is specifically contoured to match graphically patterned branches and leaves on the outer fabric layer. Preferably, the depth of the 3D fabric varies from about 0.25 inches to about 4.0 inches, and more preferably from about 0.25 inches to about 2.0 inches. Outer fabric layer patterns may include trees, leaves, branches, grassland vegetation, and the like. The patterns may be selected from different types of outdoor environments: oak woods, pine forests, maple forests, and the like.
In a presently preferred embodiment, the articles of clothing are constructed out of pattern panels (e.g., sleeves, collar, back, etc. . . . ) that are formed in molded sections. Each section includes all the pattern panels for the given article of clothing. The pattern panels will be arranged on the molded sections to minimize waste. Clothing articles made of 3D fabrics include normal clothing features such as pockets and zippers.
In another presently preferred embodiment, the printed or graphical patterns on the outer fabric layer are selected or designed to match the physical depth of the 3D fabric, i.e., a printed branch on the pattern will correspond with the shape of the branch on the 3D fabric. This is useful for camouflage and other applications. However, it is within the scope of the invention to have 3D physical patterns that do not match the graphical patterns.
In one aspect, the invention is a three-dimensional fabric.
In another aspect, the invention is an article of clothing incorporating a three-dimensional fabric.
In another aspect, the invention is a process of making a three-dimensional fabric.
In another aspect, the invention is a process of making an article of clothing incorporating a three-dimensional fabric.
Various fabrics were tested for their suitability and limitations for use in this invention. Referring to
In Table 1, the following abbreviations are used as column headings:
The test results showed that most of the fabrics varied significantly (i.e., had bleed-through or staining) even without the upper mold being applied. Others failed with a low pressure (currently calculated to be about 0.03 psi) being applied. Most of the fabrics tested failed at a high pressure (currently calculated to be over 0.10 psi) being applied. Though the pressure applied may be measured and calculated to classify fabrics as described in this specification, fabric classification may also be done empirically by comparison between fabrics.
The overall effect of this third embodiment of the 3D fabric 100 is to present an outer surface 102 with a 3D pattern of ridges/veins 104, where the foam segments 106 are largely indistinguishable from the spacer segments 108 and the hubs 112 because of the tendency of the foam segments 106 to hold the traditional fabric 102 of the spacer segments 108 and the hubs 112 in a three-dimensional conformation.
The foam layer 106 is comprises a polymer foam. Polyurethane is a preferred material. Polyurethane foams are forms from reacting two components (isocyanate and polyol). When the two components are mixed, a polymerization reaction occurs. The reaction includes a period when the foam begins to expand and air pockets form. The time from the mixing to the time of the foam reaching its largest volume is the “rise time.” After the rise time, the foam remains tacky and problematic to handle for a period. The time from the mixing to the time when the foam has lost its tackiness is called the tack free time.
Because of the density and viscosity of the foam mixture, it is preferable that the foam mixture be applied to the top of the outer fabric layer during manufacturing. This can be done manually, though mixing of the components of the foam mixture and application of the foam mixture over the outer fabric layer are preferably done by machine. A variety of mixing heads are presently available to mix the components. Specialty automated processes and robots may be designed to apply the foam mixture in desired amounts at particular points depending on the desired product.
The process begins by placing the outer fabric layer 102 pattern side down over the mold 120 and securing it in place.
Manufacture of the 3D fabric 100 requires fitting an essentially two dimensional traditional fabric 102 into a 3D shape 100. Stretching of the fabric 102 is not desirable because it may make the fabric more porous and lead to bleeding and/or staining. Another problem may be bunching of the fabric in certain areas, resulting in a less appealing appearance. To reduce and avoid stretching and bunching, it is sometimes desirable to form different foam segments 106 in a sequence as opposed to forming all of them at the same time.
The essential function of the fabric holders 126 is to keep the fabric 102 in contact with the groove 122 of the mold 120 when forming a foam segment 106. Because of the tackiness of the foam mixture before the tack free time, it is desirable to avoid the foam mixture from contacting the fabric holders 126.
Fabric holders 126 can be designed in any configuration as long as they perform their function.
Manufacture of 3D fabrics 100 may be done by producing individual sheets having defined sizes. For large scale production, however, it is desirable that the manufacture of the 3D fabric 100 be performed in a continuous process, as shown in
The operations shown in
It is essential to the invention that the outer fabric layer 102 and the dimensional layer 106 are integrally bonded to each other. Such bonding is achieved by the molding process. The outer traditional fabric layer 102 is breathable and porous, allowing adhesion of the fabric layer and foam mixture before the foam mixture sets. When the foam mixture sets and forms the dimensional layer 106, it also binds the dimensional layer 106 to the outer fabric layer 102. The dimensional layer 106 is preferably polyurethane. Polyurethane at a density of about or below three pounds per cubic foot is a preferable material for its light weight, washability, and durability. Presently preferred polyurethanes include 3 lb. FlexFoam-iT!® by Smooth-On.
The polymer foam may be a closed-cell foam to deter the foam from taking on moisture. The polymer foam may be breathable. However, since the 3D fabric 100 has flat areas 102 without foam, the overall fabric may still be breathable even though the foam segments are not.
The hubs 112 and spacer segments 108 of the 3D fabric 100 allow for flexibility and comfort when the fabric is incorporated into items of apparel. Without the hubs 112 and spacers 108, a similar 3D fabric would be somewhat rigid. The hubs 112 and spacers 108, combined with relatively short vein segments 104, allow the fabric to conform to the contours of the body and easily bend with movement. Flexibility of the foam component also contributes to flexibility of the overall 3D fabrics 100. Low density, flexible foams are highly preferable to high density, rigid foams in this regard. Example 2 describes stiffness testing of a preferred embodiment of the invention. A k value may be calculated from the example. It is presently preferable that the veins of the 3D fabrics of the invention are between about 0.5 and 2.0 times the k value in example 2.
A body may have a rotational stiffness, k, given by
where
M is the applied moment
θ is the rotation. (from Wikipedia)
A prototype 3D fabric 100 having acceptable flexibility was tested for stiffness. The vein segment 104 tested included the outer fabric layer 102 and the foam layer 106. The vein segment 104 was about ¼ inch in diameter (thickness) and 4 inches in length. The fabric 102 was Amerisuede and the foam 106 was Flex Foam-It III (Closed cell polyurethane 3 lb density). The vein segment was easily compressible and bendable.
In the testing, one end of the vein segment 104 was secured and the rest of the segment was unsupported. Quarters were placed on the vein segment 104 two inches from the secured end and the resulting bending was measured. The weight of each quarter was about 5.67 grams. The first quarter resulted in a 5 degree angle. Each subsequent quarter produced an additional 5 degrees of bending as follows: 2 quarters=10 degrees, 3 quarters=15 degrees, etc. A maximum of 6 quarters were added, which produced a 30 degree angle.
When used for ordinary items of apparel, the 3D effect invites touching. Softness of the outer fabric 102 is also important to the invention. Preferable 3D fabrics 100 are soft to the touch because of the qualities of the traditional fabric layer.
220 grams per square inch Amerisuede (universal name is 3-bar) having a brushed polyester outer layer is an acceptably soft outer fabric. Preferable outer fabrics for use with the invention are at least as soft as this fabric.
Bleeding and staining are two potential problems in the manufacturing of the 3D fabrics of the invention. Bleeding results in the foam mixture penetrating the outer layer before the polymerization reaction is complete, and results in visible foam on the outer surface of the fabric. Staining is less obvious than bleed, but results in discoloration of the outer fabric layer. Several variables may affect these problems. The variables include: 1. type of fabric (cotton, polyester, blend, etc.); 2. Porosity of fabric (woven vs. knit, tightness of weave or knit, thread count, etc. . . . ); 3. Fabric treatments (waterproofing, starch, etc. . . . ); 4. type of foam mixture; 5. amount of foam mixture; 6. timing and temperature during molding; 7. pressure on foam during molding; and 8. use of catalysts or other chemical additives in the foam mixture.
For applications where the prevention of bleed-through and staining are important,
preferred fabrics include: tightly-woven synthetic microfibers, tightly-knit synthetic microfibers, tightly-woven natural microfibers, tightly-knit natural microfibers, and woven cotton/polyester blends with a thread count above 150. “Tightly-woven” means impermeable to the foam mixture at a rise-time pressure less than about 0.10 psi. Specifically preferred fabrics include Ultrasuede and 100% polyester knit fleece.
Silicon molds may be used for low volume applications of the manufacturing process. For high volume applications, especially where temperature control is critical, molds made of metals such as aluminum are preferable.
The 3D fabrics 5, 26 and 100 of the invention are easily sewable using conventional equipment, as the dimensional layer is compressible during the sewing process. However, in some applications where thick dimensional layers are desired in portions of the fabric, it may be desirable to design and manufacture the fabric to have thinner areas of the dimensional layer in accordance with desired applications.
The 3D fabrics of the invention have a wide variety of applications. They may be used for camouflage hunting apparel. They may be used for military camouflage apparel. They may be used for producing ordinary apparel (such as coats, pants, hats, shoes, etc.) with interesting visual effects. They may be used for producing ordinary apparel for their insulating properties. They may be used for furniture coverings. They may be used in wall coverings. They may be used in set designs. Specialty outer and inner fabric layers may be incorporated for properties such as sonic insulation, thermal insulation, heat retention, heat reflectivity, indetectability to remote sensors (radar, sonar, infra-red detectors, and the like). Electronics may be molded into the dimensional layer for purposes of communication, monitoring of body functions, lighting and the like). Other applications of the fabrics will also become apparent over time.
The present invention includes materials and methods to produce unique wearable three-dimensional (3-D) fabrics. The fabrics comprise a dimensional layer made of foam and an outer layer of traditional fabric, which may be patterned or dyed. The dimensional layer may be molded to have contours matching the pattern of the outer layer, with the resulting multilayer fabric having both physical and graphical depth.
One application of this technology is to create camouflaged clothing articles. For example, a suit comprising a jacket and pants may have a tree or woods motif, where the fabric is specifically contoured to provide physical depth to graphically patterned branches and leaves. Preferably, the depth of the veins of the 3D fabric varies from about 0.25 inches to about 4.0 inches, and more preferably from about 0.25 inches to about 2.0 inches. Outer fabric layer patterns may include trees, leaves, branches, grassland vegetation, and the like. The patterns may be selected from different types of outdoor environments: oak woods, pine forests, maple forests, and the like.
In a presently preferred embodiment, the printed or graphical patterns on the outer fabric layer are selected or designed to match the physical depth of the 3D fabric, i.e., a printed branch on the pattern will correspond with the shape of the branch on the 3D fabric. This is useful for camouflage and other applications. However, it is within the scope of the invention to have 3D physical patterns that do not match the graphical patterns.
In one aspect, the invention is a three-dimensional fabric 100 comprising: a traditional fabric outer layer 102; and a dimensional layer 106 formed of polymer foam integrally bonded with the outer layer 102, said dimensional layer 106 having a variable thickness, where the 3D fabric 100 has flat areas without a dimensional layer 106, vein segments 104 having a dimensional layer 106, and spacer segments 108 without a dimensional layer between the vein segments. The dimensional layer 106 preferably has a (optionally) variable thickness between about 0.25 and 4.0 inches. The dimensional layer more preferably has a (optionally) variable thickness between about 0.25 and 2.0 inches. The density of the foam is preferably between about 1 and 4 pounds per cubic feet. The density of the foam is more preferably between about 2.5 and 3.5 pounds per cubic feet. The stiffness of the vein segments 104 is preferably between about 0.5 and 4 times the k value calculated from example 1. The stiffness of the vein segments is more preferably between about 0.5 and 2 times the k value calculated from example 1. The vein segments 104 are preferably between about 1 and 8 inches in length. The vein segments 104 are more preferably between about 2 and 5 inches in length. The spacer segments 108 are preferably between about 0.5 and 2 inches in length. The spacer segments 108 are more preferably between about 0.5 and 1 inch in length. The outer layer 102 may plain-colored. The outer layer may have be patterned. The pattern may have graphical depth. The physical depth of the dimensional layer may match the graphical depth of the pattern. The fabric may further comprise hub segments 112. The outer side of the traditional fabric layer is preferably at least as soft to the touch as 220 grams per square inch Amerisuede (universal name is 3-bar) having a brushed polyester outer layer.
In another aspect, the invention is an article of clothing incorporating a three-dimensional fabric.
In another aspect, the invention is a process of making a three-dimensional fabric.
In another aspect, the invention is a process of making an article of clothing incorporating a three-dimensional fabric.
While embodiments and applications of this invention have been shown and described, it would be apparent to those skilled in the art having the benefit of this disclosure that many more modifications than mentioned above are possible without departing from the inventive concepts herein. The invention, therefore, is not to be restricted except in the spirit of the appended claims.
This application claims priority to U.S. Provisional Patent Application No. 61/797,962, filed Dec. 19, 2012, and U.S. Provisional Patent Application No. 61/852,146, filed Mar. 15, 2013, the contents of which are both incorporated by reference herein.
| Number | Date | Country | |
|---|---|---|---|
| 61797962 | Dec 2012 | US | |
| 61852146 | Mar 2013 | US |
