Patent Application
20100011619
This invention relates generally to footwear, and more particularly to a one-piece upper of a shoe and a method of fabricating a one-piece upper of a shoe.
At least some known shoe uppers are constructed of certain materials, including various fabrics and adhesives, that when assembled in layers have limited breathability. Similarly, footwear that is marketed as waterproof and breathable is constructed of multiple layers that might be waterproof and might be moisture vapor permeable but are not air permeable. The waterproof liner most commonly includes a layer of polyurethane or some other material that is not air permeable. This lack of air permeability seals in the wearer's foot without access to fresh air.
Construction of conventional uppers typically involves either the use of a pattern cutout from a material, or multiple pieces cut from a material and either the single piece or the multiple pieces assembled with stitching and adhesives to form a volume shaped to encompass a wearer's foot. Often, uppers are constructed in two parts, a liner and a shoe shell, wherein the waterproof liner must be assembled inside one or more layers of the shoe shell to complete the full upper of the shoe. However, methods used to improve the breathability of the shoe tend to reduce the waterproof capability of the shoe
In one aspect of the invention, a method of fabricating a bootie for use in a footwear item is provided. The method includes laminating a plurality of layers of material together into a single air permeable, moisture vapor permeable, and waterproof sheet, and forming a bootie out of the sheet. The sheet includes a first membrane layer having a first side and a second side; the first layer being air permeable, moisture vapor permeable, and waterproof. The sheet also includes a second protection layer having a first side and a second side. The second layer is positioned between the first layer and an outside environment when the footwear item is completed, and configured to facilitate protecting the first layer from an outside surrounding environment. In addition, the sheet can include a third bonding layer having a first side and a second side. The third layer is positioned between the first layer and the second layer to facilitate bonding of the first layer to the second layer.
In another aspect of the invention, a bootie for use in a footwear item is provided. The bootie includes a body formed of a sheet of a plurality of laminated layers of material that forming a single air permeable, moisture vapor permeable, and waterproof sheet. The sheet includes a first membrane layer having a first side and a second side; the first layer being air permeable, moisture vapor permeable, and waterproof. The sheet also includes a second protection layer having a first side and a second side. The second layer is positioned between the first layer and an outside environment when the footwear item is completed, and configured to facilitate protecting the first layer from an outside surrounding environment. In addition, the sheet can include a third bonding layer having a first side and a second side. The third layer is positioned between the first layer and the second layer to facilitate bonding of the first layer to the second layer.
In yet another aspect of the invention, an article of footwear including an outsole and a bootie attached to an insole is provided. The bootie includes a body formed of a sheet of a plurality of laminated layers of material that forming a single air permeable, moisture vapor permeable, and waterproof sheet. The sheet includes a first membrane layer having a first side and a second side; the first layer being air permeable, moisture vapor permeable, and waterproof The sheet also includes a second protection layer having a first side and a second side. The second layer is positioned between the first layer and an outside environment when the footwear item is completed, and configured to facilitate protecting the first layer from an outside surrounding environment. In addition, the sheet can include a third bonding layer having a first side and a second side. The third layer is positioned between the first layer and the second layer to facilitate bonding of the first layer to the second layer.
A common limitation of footwear that is waterproof and moisture permeable is that such footwear is air impermeable. One example of an embodiment that does not exhibit the common air impermeability limitation is footwear having a one-piece upper made from a multi-layer laminate that is waterproof, moisture vapor permeable, and air permeable. The embodiments described herein include such one-piece upper and a method for constructing such a one-piece upper.
The terms ‘waterproof’ and ‘liquid impermeable’ are used interchangeably throughout the present disclosure. As used herein, ‘liquid impermeable’ is defined as that which upper 104, including the insole, does not leak as indicated by the presence of detectable liquid on the exterior of upper 104 when applied with water having maximum pressure of 200 millibar (2.901 p.s.i.g.) for one minute.
In addition, bootie 106 is moisture vapor permeable, which allows perspiration and other vapors to exit bootie 106 while still remaining impervious to fluids such as water. In an exemplary sense, liquid vapor permeability or the moisture vapor transmission rate (MVTR) of bootie 106 is preferably defined by the test method designated ISO 15496, which provides for moisture vapor transmission of at least 337 grams per square meter (9.94 ounces per square yard) or more of water vapor in a twenty-four hour period through bootie 106. Preferably, the moisture vapor transmission rate is between 1,500 grams per square meter to 15,000 grams per square meter of water vapor in a twenty-four hour period through bootie 106.
In an exemplary sense, ‘air permeability’ of bootie 106 can be defined by the test method designated ASTM D737-96, by the American Society for Testing and Materials. This is preferably measured by a Frazier Air Permeability Tester, a Textest FX 3300 Air Permeability Tester or an equivalent type of testing device. The air permeability needs to provide for air flow of at least 0.03 cubic centimeters per minute per square centimeter at a pressure of a 1.27 centimeter water column (0.05 cubic feet per minute per square foot at a pressure of a 0.5 inch water column) through bootie 106 portion of upper 104. Preferably, there is air flow of at least 0.05 cubic centimeters per minute per square centimeter at a pressure of a 1.27 centimeter water column (0.1 cubic feet per minute per square foot at a pressure of a 0.5 inch water column) through bootie 106. More preferably there is air flow of at least 0.15 cubic centimeter per minute per square centimeter at a pressure of a 1.27 centimeter water column (0.3 cubic feet per minute per square foot at a pressure of a 0.5 inch water column) through bootie 106 and most preferably there is air flow of at least 0.51 cubic centimeter per minute per square centimeter at a pressure of a 1.27 centimeter water column (1.0 cubic feet per minute per square foot at a pressure of a 0.5 inch water column) through bootie 106.
In the exemplary embodiment, first layer 210 is formed of an air permeable, moisture vapor permeable, and waterproof material that includes microporous membranes. An example of such material is eVENT® Fabric, which is a chemically treated expanded polytetrafluoroethylene (hereinafter also referred to as ePTFE) membrane commercially available from BHA Technologies, Inc. of Kansas City, Mo.
Other exemplary commercial available materials that may be used for forming multilayer laminated sheet 200 are Gore-Tex™ XCR™ also known as VISI000001, TETRATEX®, SUPOR®, VERSAPOR®, PORELLE®, MILLIPORE®, ENTRANT®, FOLIO I™, ACE-SIL®, FLEX-SIL®, MICROPOR-SIL®, and CELLFORCE®.
Second layer 220 in the exemplary embodiment includes a closed-cell foam such as a polyester fiber foam commercially available as Nu-foam®. In various alternative embodiments, second layer 220 includes at least one of an open-cell foam or other padding-type materials. Although in an exemplary embodiment, the closed-cell foam is waterproof, it is also air impermeable and water vapor impermeable without certain modifications. Therefore to ensure that second layer 220 is air permeable and moisture vapor permeable, the material is perforated prior to being laminated into multi-layer laminated sheet 200. Although second layer 220 is perforated with a plurality of holes to enable it to be air permeable and water vapor permeable, but not waterproof, one or more layers of multi-layer laminated sheet 200, and at least first layer 210, is still waterproof and thus ensures that multi-layer laminated sheet 200 is waterproof.
Third layer 230 includes a bonding material to facilitate bonding of first layer 210 and second layer 220. Third layer 230 facilitates a strong bond that is often otherwise unreliable without the use of third layer 230. In the exemplary embodiment third layer 230 includes a textile material, for example, but not limited to, scrims, tricot knits, and non-wovens.
Fourth layer 240 is configured to form an inside surface, or lining of upper 104 (shown in
Fifth layer 250 is configured to form an outside surface, or shell (not shown) of upper 104 (shown in
Stitching seams 322, 340, and 350 can be sealed with seam tape 324, 344, and 354 positioned over stitching seams 322, 340, and 350 respectively. Heat is then applied through the application of hot air, and pressure through a nip roll is then applied to the top of seam tape 324, 344 and 354. The heat from the hot air is preselected to soften the adhesive in seam tape 324, 344 and 354 without detrimentally affecting any of the desired qualities found in pre-completion upper 300 of footwear item. An application of heat preferably ranges from about 150 degrees Celsius (302 degrees Fahrenheit) to about 250 degrees Celsius (482 degrees Fahrenheit) for most applications. A preferred application of pressure is from about 3 kilograms per square centimeter (42.67 pounds per square inch) gauge to about 5 kilograms per square centimeter (71.12 pounds per square inch) gauge. However, the applied temperature and pressure are dependent on the type of material used for upper 300, the threads used to create seams 320, 322, 330, 340, and 350, the adhesives and the type of material utilized for seam tape 324, 344, and 354. By such a process, a solid structural weld is formed that provides at least a substantially liquid impermeable quality in seams 322, 340, and 350 that is approximately equivalent to the liquid impermeability quality of the remainder of upper 300 and insole 304 having seams 322, 340, and 350, covered and sealed as described further.
Subsequent to seam tape 324, 344, and 354, being applied, and insole 304 being stitched to bootie 302 forming upper 300, an insole sealing gasket 360, having a first side 362 and a second side 364, is applied to upper 300. A bonding agent is applied to first side 362 of insole sealing gasket 360 as well as the base of upper 300 including covering seams 330 and 320, flaps 310, and insole 304. First side 362 of insole sealing gasket 360 is attached to the base of upper 300, covering seams 330 and 320, flaps 310, and insole 304, through the application of heat and pressure as described above. Sealing gasket 360 acts as a sealing agent for front insole stitching seam 320, rear insole stitching seam 330, and flaps 310. By such a process, a solid structural weld is formed that provides at least a substantially liquid impermeable quality in seams 320 and 330, and flaps 310 that is equivalent to the liquid impermeable quality of seams 322, 340, and 350, are with seam tape 324, 344, and 354.
In various alternative embodiments, insole 304 is impervious to both moisture vapor and air. As used herein liquid impermeable is defined as insole 304 not leaking, as indicated by detectable liquid on the exterior of insole 304 when applied with water having maximum pressure of 200 mbar (0.5 p.s.i.g.) for one minute.
In an exemplary embodiment, the absence of air permeability of insole 304 is defined by, for example, a test method designated ASTM D737-96, by the American Society for Testing and Materials. The air permeability is configured to provide for an air flow of less than 0.03 cubic centimeters per minute per square centimeter at a pressure of a 1.27 centimeter water column (0.05 cubic feet per minute per square foot at a pressure of a 0.5 inch water column) through insole 304.
In addition, in an alternative embodiment, insole 304 is substantially impervious to moisture vapor transmission. The liquid vapor permeability or the moisture vapor transmission rate of insole 304 may be defined by the test method designated JIS L 1099:1993 B2 by the Japanese Standards Association, which provides for less than 500 grams per square meter (14.85 ounces per square yard) of water vapor in a twenty-four hour period through insole 304.
In addition, in the exemplary embodiment, insole 304 is substantially inelastic. As used herein, “inelastic” is defined as material that, when subjected to a stress-strain test, provides less than 100% recovery when deflected more than 10% from a yield point.
In the exemplary embodiment, insole 304 includes, but is not limited to, inelastic and thermoplastic material, e.g., sheet goods, such as polypropylene, polyethylene, polyester, inelastic polyurethane, nylon, and vinyl. In an alternative embodiment, insole 304 includes, but is not limited to, fiber reinforced polymeric materials. This can include, but is not limited to, fibers made of polyester, nylon, polypropylene, polyethylene, rayon, and cotton. Yet in another alternative embodiment, insole 304 includes, but is not limited to, an all non-thermoplastic material such as reactive polyurethane, epoxy, styrene, butadiene, acrylic(s), and vulcanized rubber.
Other exemplary commercially available materials that may be used for forming insole 304 are BONTEX®, UPACO™, SOVERE™, MOREL™, ALCANTARA®, VITA™, RHENOFLEX®, and FOOTLEVERS®.
In an alternative embodiment, insole 304 is moisture permeable. Exemplary commercially available materials that may be used for forming a moisture permeable insole 304 are PORELLE®, PORON®, and TEXON®.
Exemplary embodiments of the invention are described above in detail. The methods and components are not limited to the specific embodiments described herein, but rather, components of systems and/or steps of the methods may be utilized independently and separately from other components and/or steps described herein. For example, the methods may also be used in combination with other footwear construction methods, and are not limited to practice with only the construction methods as described herein. Rather, the exemplary embodiment can be implemented and utilized in connection with many other footwear applications.
Although specific features of various embodiments may be shown in some drawings and not in others, this is for convenience only. In accordance with the principles of the invention, any feature of a drawing may be referenced and/or claimed in combination with any feature of any other drawing.
