Footwear upper having a unitary knit structure and method of manufacturing

Abstract

A footwear upper has a unitary knit structure with a knit outer face layer, a knit inner face layer, and a knit intermediate layer integrally knit to define forefoot, midfoot, and heel regions of the footwear upper. The knit intermediate layer is disposed between the knit outer face layer and the knit inner face layer at a plurality of first zones and absent from or present in a lesser amount or a lesser density in a plurality of second zones, the first zones alternating with the second zones in a longitudinal direction, and the unitary knit structure having a greater modulus of elasticity in the longitudinal direction in the first zones than in the second zones, and a greater breathability in the second zones than in the first zones. A method of manufacturing the footwear upper is disclosed.

What is claimed is: 
     
         1 . A method of manufacturing an article of footwear, the method comprising:
 simultaneously knitting a knit outer face layer, a knit inner face layer, and a knit intermediate layer with one another to define a unitary knit structure having a forefoot region, a midfoot region, and a heel region of a footwear upper; and   wherein said knitting is such that the knit intermediate layer is disposed between the knit outer face layer and the knit inner face layer at a plurality of first zones and absent from or present in a lesser amount or density in a plurality of second zones, the first zones alternating with the second zones in a longitudinal direction of the article of footwear, and the unitary knit structure having a greater modulus of elasticity in the longitudinal direction in the first zones than in the second zones, and having greater breathability in the second zones than in the first zones.   
     
     
         2 . The method of manufacturing of  claim 1 , further comprising:
 assembling the unitary knit structure in an article of footwear such that the knit outer face layer is disposed at an outer side of the unitary knit structure and the knit inner face layer is disposed at an inner side of the unitary knit structure.   
     
     
         3 . The method of manufacturing of  claim 1 , wherein said knitting is such that:
 an average fore-aft width of the first zones in the heel region is greater than an average fore-aft width of the first zones in the forefoot region; and   an average fore-aft width of the second zones in the forefoot region is greater than an average fore-aft width of the second zones in the heel region.   
     
     
         4 . The method of manufacturing of  claim 3 , wherein said knitting is such that boundaries between adjacent ones of the first zones and the second zones extend substantially linearly in a transverse direction of the footwear upper. 
     
     
         5 . The method of manufacturing of  claim 4 , wherein said knitting is such that:
 the first zones progressively increase in fore-aft width in a rearward direction at least from the forefoot region to the midfoot region; and   the second zones progressively increase in fore-aft width in a forward direction at least from the midfoot region to the forefoot region.   
     
     
         6 . The method of manufacturing of  claim 1 , wherein said knitting is such that:
 the knit outer face layer comprises a mesh pattern including first knitted-in holes of a first size; and   the knit inner face layer comprises a mesh pattern including second knitted-in holes of a second size larger than the first size and overlapping with the first knitted-in holes.   
     
     
         7 . The method of manufacturing of  claim 6 , wherein the knit outer face layer does not include the second knitted-in holes such that a surface of the knit outer face layer is smoother than a surface of the knit inner face layer at each of the first zones and at each of the second zones. 
     
     
         8 . The method of manufacturing of  claim 6 , wherein said knitting is such that:
 the first knitted-in holes of the knit outer face layer each have a first maximum length in the longitudinal direction;   the second knitted-in holes of the knit inner face layer each have a second maximum length in the longitudinal direction; and   the second maximum length is from about two to about four times the first maximum length.   
     
     
         9 . The method of manufacturing of  claim 8 , wherein the second maximum length is greater than a maximum width of each of the second knitted-in holes such that the modulus of elasticity of the unitary knit structure in the second zones is greater in the longitudinal direction than in a transverse direction. 
     
     
         10 . The method of manufacturing of  claim 6 , wherein said knitting is such that:
 the knit outer face layer does not include the second knitted-in holes and the knit inner face layer does not include the first knitted-in holes;   the knit outer face layer includes a first plurality of yarns, the knit inner face layer includes a second plurality of yarns separate and distinct from the first plurality of yarns, the first plurality of yarns are not included in the knit inner face layer and the second plurality of yarns are not included in the knit outer face layer;   perimeters of the first knitted-in holes are defined by the first plurality of yarns and not by the second plurality of yarns; and   perimeters of the second knitted-in holes are defined by the second plurality of yarns and not by the first plurality of yarns.   
     
     
         11 . The method of manufacturing of  claim 1 , wherein said knitting is such that the knit outer face layer comprises one or more monofilament yarns and the knit inner face layer comprises one or more multi-filament yarns and/or said knitting is such that the knit intermediate layer comprises one or more multi-filament yarns. 
     
     
         12 . The method of manufacturing of  claim 1 , wherein said knitting is such that the knit inner face layer comprises one or more recycled drawn polyester multi-filament yarns. 
     
     
         13 . The method of manufacturing of  claim 1 , wherein said knitting is such that the knit inner face layer, the knit outer face layer, and the knit intermediate layer comprise yarns recyclable by melting the yarns and re-extruding melted material of the melted yarns. 
     
     
         14 . The method of manufacturing of  claim 1 , wherein said knitting is such that:
 the knit outer face layer comprises drawn polyester monofilament yarns;   the knit inner face layer comprises drawn polyester multi-filament yarns; and   the knit intermediate layer comprises cationic dyed polyester yarns.   
     
     
         15 . The method of manufacturing of  claim 1 , wherein said knitting is such that the unitary knit structure is substantially free of yarn comprising a thermoset material. 
     
     
         16 . The method of manufacturing of  claim 1 , further comprising:
 fusing or stitching a textile comprising a thermoset material to the unitary knit structure.   
     
     
         17 . The method of manufacturing of  claim 16 , wherein the textile is fused to or stitched to the unitary knit structure to define an ankle collar. 
     
     
         18 . The method of manufacturing of  claim 1 , further comprising:
 cutting an ankle opening in the unitary knit structure beginning at a rear edge of the unitary knit structure and ending at the rear edge of the unitary knit structure.   
     
     
         19 . The method of manufacturing of  claim 1 , further comprising:
 securing a sole structure directly to an outer surface of the knit outer face layer along an outer perimeter of the unitary knit structure.   
     
     
         20 . The method of manufacturing of  claim 1 , wherein said knitting is such that the knit inner face layer and the knit outer face layer are coextensive, one-piece layers, each extending to and defining an entire outer perimeter of the unitary knit structure including a medial edge, a lateral edge, a rear edge, and a front edge and characterized by an absence of sewn seams.