Knit element with cushioning and rigidity zones, uppers and footwear with the same, and methods of manufacturing the same

Abstract

Knit elements, including knit heel elements, configured with cushioning and rigidity features, along with uppers and footwear having the same, and methods of manufacturing and integrating the same in footwear. The cushioning and rigidity features may be provided in a knit element by positioning cushioning yarns and yarns comprising a thermoplastic material in selected zones and/or knit layers. Heat and pressure may be selectively applied to knit zones to melt the thermoplastic material and form a thermoformed layer that has a desired degree of hardness and/or rigidity. The thermoformed layer can form at least part of an integrally knit heel-counter of an upper for an article footwear, e.g., without introducing separate components traditionally attached or integrated to form the heel-counter.

1 . A knit heel element, comprising:
 a first knit composite zone comprising a low-melting thermoplastic material and a first knit structure;   a second knit composite zone integrally extending from the first knit composite zone, the second knit composite zone comprising the low-melting thermoplastic material and a second knit structure, wherein a concentration by weight of the low-melting thermoplastic material is less in the second knit composite zone compared to the first knit composite zone; and   a knit collar integrally extending from the second knit composite zone, the knit collar comprising one or more elastic yarns.   
     
     
         2 . The knit heel element of  claim 1 , wherein the low-melting thermoplastic material is thermoformed, defining a heel counter having a higher stiffness than a remainder of the knit heel element. 
     
     
         3 . The knit heel element of  claim 1 , wherein the first knit structure comprises a first knit layer and a second knit layer. 
     
     
         4 . The knit heel element of  claim 1 , wherein the low-melting thermoplastic material in the first knit composite zone comprises a thermoformed layer. 
     
     
         5 . The knit heel element of  claim 4 , wherein the thermoformed layer is at least partially positioned between a first knit layer and a second knit layer of the first knit structure. 
     
     
         6 . The knit heel element of  claim 4 , wherein the thermoformed layer comprises at least one cushioning yarn. 
     
     
         7 . The knit heel element of  claim 4 , wherein the thermoformed layer comprises at least one high-melting thermoplastic yarn. 
     
     
         8 . The knit heel element of  claim 1 , wherein the second knit structure comprises at least a first knit layer and a second knit layer. 
     
     
         9 . The knit heel element of  claim 8 , wherein the second knit structure comprises a first number of yarn ends each formed entirely of a low-melting thermoplastic material positioned between the first knit layer and the second knit layer. 
     
     
         10 . The knit heel element of  claim 9 , wherein the second knit structure comprises a second number of yarn ends each comprising a cushioning yarn positioned between the first knit layer and the second knit layer, wherein the first number of yarn ends each formed entirely of the low-melting thermoplastic material are thermoformed, in an area between the first knit layer and the second knit layer. 
     
     
         11 . The knit heel element of  claim 10 , wherein the low-melting thermoplastic material that is thermoformed between the first knit layer and the second knit layer is interspersed among the second number of yarn ends each comprising a cushioning yarn. 
     
     
         12 . A knit heel element, comprising:
 a first knit zone comprising a first hardness;   a second knit zone integrally extending from the first knit zone, the second knit zone comprising a second hardness that is less than the first hardness; and   a knit collar integrally extending from the second knit zone, the knit collar comprising one or more elastic yarns.   
     
     
         13 . The knit heel element of  claim 12 , wherein the first knit zone is positioned at a lower end of the knit heel element, and the second knit zone extends from the first knit zone upward to the knit collar. 
     
     
         14 . The knit heel element of  claim 13 , wherein the first knit zone comprises a first concentration of thermoplastic polymer material per unit of surface area, and wherein the second knit zone comprises a second concentration of thermoplastic polymer material per unit of surface area, and wherein the first concentration is higher than the second concentration. 
     
     
         15 . The knit heel element of  claim 14 , wherein the first knit zone and the second knit zone comprise a thermoformed layer. 
     
     
         16 . The knit heel element of  claim 15 , wherein the thermoformed layer defines a heel-counter that has a higher stiffness than a remaining portion of the knit heel element. 
     
     
         17 . The knit heel element of  claim 16 , wherein the higher stiffness of the heel-counter is provided without a separately-formed component being incorporated into or onto the knit heel element to increase stiffness. 
     
     
         18 . An article of footwear, comprising:
 a sole structure; and   an upper secured to the sole structure, the upper comprising a knit element comprising a first knit zone and a second knit zone,   the first knit zone comprising:
 a first knit layer, 
 a second knit layer, and 
 a thermoformed layer located at least partially between the first knit layer and the second knit layer, the thermoformed layer comprising a low-melting thermoplastic material, and 
   the second knit zone comprising:
 the first knit layer, 
 the second knit layer, 
 a first number of yarn ends comprising the low-melting thermoplastic material. 
   
     
     
         19 . The article of footwear of  claim 18 , wherein the upper comprises an integrally knitted heel-counter formed by the low-melting thermoplastic material that is thermoformed. 
     
     
         20 . The article of footwear of  claim 19 , wherein the integrally knitted heel-counter has a higher stiffness than a remainder of the knit element, without a separate component incorporated into or onto the knit element to increase stiffness. 
     
     
         21 . The article of footwear of  claim 18 , wherein the thermoformed layer comprises at least one end of a cushioning yarn, and wherein the second knit zone comprises a second number of yarn ends of a cushioning yarn. 
     
     
         22 . The article of footwear of  claim 18 , wherein the first knit layer and the second knit layer each comprise a high-melting thermoplastic yarn. 
     
     
         23 . The article of footwear of  claim 18 , wherein the thermoformed layer further comprises at least one end of a high-melting thermoplastic yarn. 
     
     
         24 . The article of footwear of  claim 18 , wherein, in the second knit zone, the first number of yarn ends comprising the low-melting thermoplastic material are each entirely formed of the low-melting thermoplastic material. 
     
     
         25 . The article of footwear of  claim 23 , wherein the first number of yarn ends comprising the low-melting thermoplastic material comprise one or more of a low-melting polyethylene terephthalate yarn and a low-melting polyamide yarn. 
     
     
         26 . The article of footwear of  claim 25 , wherein the first number of yarn ends comprising the low-melting thermoplastic material are the low-melting polyethylene terephthalate yarn, and wherein a melting point of the low-melting polyethylene terephthalate yarn is less than or equal to about 135 degrees Celsius. 
     
     
         27 . The article of footwear of  claim 25 , wherein the first number of yarn ends comprising the low-melting thermoplastic material are the low-melting polyamide yarn, and wherein a melting point of the low-melting polyamide yarn is less than or equal to about 135 degrees Celsius. 
     
     
         28 . The article of footwear of  claim 18 , wherein the first number of yarn ends comprising the low-melting thermoplastic material in the second knit zone is five yarn ends. 
     
     
         29 . The article of footwear of  claim 18 , wherein a cushioning yarn is inlaid between the first knit layer and the second knit layer in the first knit zone. 
     
     
         30 . The article of footwear of  claim 18 , wherein the first number of yarn ends comprising the low-melting thermoplastic material in the second knit zone is intermittently interlooped with yarns forming one or more of the first knit layer and the second knit layer of the first knit zone. 
     
     
         31 . The article of footwear of  claim 18 , wherein the first knit zone includes a higher concentration per unit of surface area of the low-melting thermoplastic material than the second knit zone. 
     
     
         32 . An array of articles of footwear each comprising a sole structure, an upper secured to the sole structure, and a knit heel element, each knit heel element comprising a first knit layer comprising an outer-facing surface of the knit heel element, and a second knit layer comprising an inner-facing surface of the knit heel element, the array of articles of footwear comprising at least:
 a first article of footwear configured for a first category of sporting activity, a first knit heel element of the first article of footwear comprising:
 a first knit zone located at a lower portion of the first knit heel element, the first knit zone comprising a thermoformed layer comprising a low-melting thermoplastic material and at least positioned between the first knit layer and the second knit layer, and 
 a second knit zone located above the first knit zone, the second knit zone comprising a first number of yarn ends comprising the low-melting thermoplastic material and a second number of yarn ends comprising a cushioning yarn; and 
   a second article of footwear configured for a second category of sporting activity different from the first category of sporting activity, a second knit heel element of the second article of footwear comprising:
 a third knit zone located at a lower portion of the second knit heel element, the third knit zone comprising a thermoformed layer comprising the low-melting thermoplastic material and at least partially positioned between the first knit layer and the second knit layer, and 
 a fourth knit zone located above the third knit zone, the fourth knit zone comprising a third number of yarn ends comprising the low-melting thermoplastic material and a fourth number of yarn ends comprising a cushioning yarn, wherein the first knit zone of the first article of footwear and the third knit zone of the second article of footwear comprise different surface areas and/or the second knit zone of the first article of footwear and the fourth knit zone of the second article of footwear comprise different surface areas. 
   
     
     
         33 . The array of articles of footwear of  claim 32 , wherein the thermoformed layer of the first knit heel element defines a first heel-counter comprising a first stiffness that is higher than a stiffness of a remainder of the first knit zone and the second knit zone, and wherein the thermoformed layer of the second knit heel element defines a second heel-counter comprising a second stiffness that is higher than a stiffness of a remainder of the third knit zone and the fourth knit zone. 
     
     
         34 . The array of articles of footwear of  claim 33 , wherein the first stiffness and the second stiffness are different. 
     
     
         35 . The array of articles of footwear of  claim 33 , wherein the first heel-counter and the second heel-counter are each integrally formed with the first knit heel element and the second knit heel element, respectively, without a separate component being integrated therein or thereon for increasing stiffness. 
     
     
         36 . The array of articles of footwear of  claim 32 , wherein the thermoformed layer in each of the first knit zone of the first article of footwear and the third knit zone of the second article of footwear comprise at least one end of a high-melting thermoplastic yarn. 
     
     
         37 . The array of articles of footwear of  claim 32 , wherein each of the second number of yarn ends comprising the low-melting thermoplastic material in the second knit zone of the first article of footwear and the third number of yarn ends comprising the low-melting thermoplastic material in the fourth knit zone of the second article of footwear comprise one or more of a low-melting polyethylene terephthalate yarn and a low-melting polyamide yarn. 
     
     
         38 . A method of manufacturing a knit element for an upper of an article of footwear, the method comprising:
 knitting a first knit layer and a second knit layer;   positioning yarn ends comprising a low-melting thermoplastic material between the first knit layer and the second knit layer;   positioning yarn ends comprising a cushioning yarn between the first knit layer and the second knit layer; and   thermoforming at least a first knit zone of the knit element such that a thermoformed layer is formed at least partially between the first knit layer and the second knit layer, the thermoformed layer being located in a heel area.   
     
     
         39 . The method of  claim 38 , further comprising:
 forming the knit element into an upper, and   incorporating the upper into an article of footwear, such that the thermoformed layer forms an integral heel-counter in the heel area of the article of footwear.   
     
     
         40 . The method of  claim 39 , wherein the integral heel-counter is formed without a separate component being integrated into or onto the heel area for increasing a stiffness of the heel area. 
     
     
         41 . The method of  claim 38 , wherein, during thermoforming, the heel area of the knit element is thermoformed into a three-dimensional shape.