ARTICLE OF FOOTWEAR WITH A KNITTED COMPONENT

Description

CROSS-REFERENCE TO RELATED APPLICATIONS AND PRIORITY CLAIM

This non-provisional patent application claims priority to co-pending U.S. provisional patent app. No. 63/673,549, filed on Jul. 19, 2024, and titled “ARTICLE OF FOOTWEAR WITH A KNITTED COMPONENT,” the contents of which is incorporated herein by reference in the entirety.

BACKGROUND

Articles of footwear generally include two primary elements: an upper and a sole structure. The upper is secured to the sole structure and forms a void within the footwear for comfortably and securely receiving a foot. Uppers may be formed by a variety of materials, including knitted textiles. When an athlete moves their foot within a knitted upper, a force may be exerted on the athlete's foot that pushes the foot partially off the sole structure. Performance and comfort may be improved by keeping the foot contained over the sole structure during movement. Various components (e.g., synthetic leather textiles, laminate film layers, etc.) may be added and secured (e.g., glued, stitched, etc.) to a knitted upper through post-knitting processes to keep the foot contained and/or increase durability of the upper. However, such components added through post-knitting processes may increase the weight of the upper, increase production time, reduce recyclability of the upper, and impact performance in unintentional and possibly negative ways.

BRIEF DESCRIPTION OF THE DRAWINGS

Examples of aspects herein are described in detail below with reference to the attached drawing figures, wherein:

FIG. 1A illustrates a medial view of an example article of footwear in accordance with aspects herein;

FIG. 1B illustrates a lateral view of the example article of footwear of FIG. 1A in accordance with aspects herein;

FIG. 2 illustrates a top view of a knitted component of the article of footwear of FIG. 1A in accordance with aspects herein;

FIGS. 3A and 3B illustrate example stitch notation diagrams that may be used to form portions of the knitted component of FIG. 2 in accordance with aspects herein;

FIG. 4 illustrates a bottom perspective view of an upper of the article of footwear of FIG. 1A in accordance with aspects herein; and

FIGS. 5A and 5B illustrate example schematic cross-sections of a composite structure of the knitted component of FIG. 2 in accordance with aspects herein.

DETAILED DESCRIPTION

Aspects herein are directed to an article of footwear having a knitted component and methods of manufacturing a knitted component for an article of footwear, where the knitted component includes integrally knit zones with different knit densities that may provide functional benefits for certain activities. For example, containment in the upper for running shoes is desirable where the wearer typically strikes the running surface. When on a treadmill, athletes tend to shift their usual striking position to a more forward location. For example, athletes that are heel strikes off of a treadmill may be midfoot strikes on the treadmill, and athletes that are midfoot strikes off of a treadmill may be forefoot strikers on the treadmill. As such, it may be desirable to provide additional containment through the forefoot and midfoot regions of the upper. At the same time, treadmill running occurs indoors where temperatures may be warmer and there may be less natural airflow. As such, it may be desirable to provide increased breathability to the upper where possible.

To meet these goals, aspects of the disclosure include a knitted component for an upper with a first knit zone in the heel region having a lower knit density than the second knit zone in at least the midfoot region. In some aspects, the second knit zone is positioned in a forefoot region and a midfoot region. Alternatively, the second knit zone may be positioned in the forefoot region while the less dense first knit zone may be positioned in the midfoot and, in some aspects, the heel region. Having a more dense knit structure in the midfoot and/or forefoot regions provides appropriate containment where an athlete may strike his or her foot while running, particularly on a treadmill, while a less dense knit structure elsewhere, such as the heel region, may provide increased breathability to the wearer.

In some aspects, the knitted component of the upper extends at least partially underfoot. In some aspects, the knitted component extends across the entire underfoot portion of the upper. This underfoot portion is joined to the sole structure. A knit structure that is less dense tends to provide less surface to which the sole structure can attach. As such, a film, such as a thermoplastic film, may be applied over at least part of the knitted component and may help the sole structure attach to the upper. In some aspects, the thermoplastic film layer is applied on an inner-facing surface of the knitted component and, after exposure to heat and/or pressure, melts to create or at least partially encapsulate the knit structure and extend towards the outer-facing surface. The result is a composite structure that includes a knit structure, which may be a knit mesh that has a relatively open knit structure, and the thermoplastic film layer. The sole structure may then be bonded to both the knit mesh component and the thermoplastic film layer at the outer-facing side of the upper. By placing the thermoplastic film on the inner-facing side of the knitted component, the sole structure may bond to both the knitted component and the film to create a stronger bond compared to being attaching to a film positioned between the sole structure and the knitted component.

As used herein, an article of footwear generally includes a sole structure secured to an upper. The article of footwear described herein may comprise a running shoe, a baseball shoe, a basketball shoe, a cycling shoe, an American football shoe, a tennis shoe, a global football shoe, a training shoe, a walking shoe, a hiking shoe, and the like. The concepts described herein may also be applied to other footwear types that are considered non-athletic such as dress shoes, loafers, sandals, and work boots. As used herein, the article of footwear may be divided into different general regions. A forefoot region generally includes portions of the article of footwear that correspond to the toes and joints connecting the metatarsals with the phalanges. A midfoot region generally includes portions of the article of footwear corresponding with an arch area and an instep area of the foot. A heel region generally corresponds with rear portions of the foot including the calcaneus bone. The article of footwear described herein may include a lateral side that corresponds with an outside area of the foot (i.e., the surface that faces away from the other foot) and a medial side that corresponds with an inside area of the foot (i.e., the surface that faces toward the other foot). The different regions and sides described above are intended to represent general areas of footwear to aid in the following discussion and are not intended to demarcate precise areas. The different regions and sides may be applied to the article of footwear as a whole, to the knitted upper, and to the sole structure.

The term “outer-facing surface” as used herein means a surface of the knitted upper or article of footwear that faces the external environment. In some aspects, the outer-facing surface may mean the outermost-facing surface of the knitted upper or article of footwear. The term “inner-facing surface” as used herein means a surface of the knitted upper or article of footwear that faces a void for receiving the wearer's foot. In some aspects, the inner-facing surface may mean the innermost-facing surface of the knitted upper or article of footwear. The term “interior to” when referring to one object's relation to another object, means closer to the void for receiving the wearer's foot, and the term “exterior to” when referring to one object's relation to another object means closer to an external environment. Positional terms such as “above” and “below” are in relation to the sole structure of the article of footwear positioned on a planar surface.

The term “knit” such as is used herein to describe the knitted component refers to a textile piece that is formed from at least one yarn that is manipulated (e.g., with a knitting machine) to form a plurality of intermeshed loops (also known as interlooping) that define courses and wales. The term “course,” as used herein, refers to a predominantly horizontal row of knit loops (in an upright textile, as it is knit on the knitting machine) that is produced by adjacent needles during the same knitting cycle. The course may comprise one or more stitch types, such as a knit stitch, a missed (float) stitch, a held stitch, a tuck stitch, a transfer stitch, a rib stitch, and the like, as these terms are known in the art of knitting. The term “course-wise direction” refers to a direction that is parallel to the knit courses of the textile piece. The term “wale,” as used herein, is a predominantly vertical column of intermeshed or interlooped knit loops, generally produced by the same needle at successive (but not necessarily all) courses or knitting cycles. The term “wale-wise direction” refers to a direction that is parallel to the knit wales of the textile piece.

The term “single knit construction” as used herein refers to a single-layer knit construction generally formed on a single needle bed (i.e., a single-bed construction). In some examples, a single knit construction may be formed on a multi-bed knitting machine by knitting a number of knit courses on a first needle bed of the knitting machine and then transferring all of the loops to a second needle bed of the knitting machine where a number of knit courses are then knit, which may be repeated a number of times. In this way, even though two knitting beds are used, the resulting textile maintains a single knit construction. Common single knit constructions include single jersey. The term “double knit construction” as used herein refers to a knit construction that is generally formed on at least two needle beds of a knitting machine (i.e., a multi-bed construction). Such multi-bed knit constructions may be characterized by two opposing faces or layers of knit loops and/or tucks, e.g., one face/layer of loops formed on a first needle bed (e.g., a first knit layer), and a second face/layer of loops formed on a second needle bed (e.g., a second knit layer). In example aspects, the two faces/layers may be joined by yarns that interloop with yarns in both the first face/layer and the second face/layer of the double-knit construction (e.g., transfer yarns). However, aspects herein contemplate that the two faces/layers may not be joined or may be joined only along the sides such that a space or potential space is formed between the two faces/layers. Common double knit constructions include double jersey, rib, interlock, cardigan, other “double bed” knit structures initially formed on at least two needle beds, and other knit structures having two opposing faces/layers of knit loops or tucks, including full-gauge and less-than-full-gauge variations of those structures.

The term “integrally knit,” as used herein, may mean a knit textile having a yarn from one or more knit courses in a first area being interlooped with one or more knit courses of another area. The interlooping may be through any of the above stitch types. In this way, areas that are integrally knit together have a seamless transition such that they seamlessly extend from one another. The term “integrally knit opening” as used herein refers to openings formed through an intentional knitting action (also known as “engineered openings”) as opposed to the inherent spacing between adjacent sections of yarns in a knit structure. For example, the openings may be created through transfer stitches, as is known in the art of knitting. The transfer process may include a two-needle transfer that would result in an opening that generally extends the distance of two knit wales, a one-needle transfer that would result in an opening that generally extends the distance of one knit wale, and the like. In some aspects, the integrally knit openings are sufficiently large and/or concentrated to form a knit mesh structure.

Forming an article, such as an upper, using a knit construction may provide advantages including, but not limited to, a particular degree of elasticity (for example, as expressed in terms of Young's modulus), breathability, bendability, strength, moisture absorption, weight, abrasion resistance, and/or a combination thereof. These characteristics may be accomplished by selecting a particular knit structure, by varying the size and tension of the knit structure, by using one or more yarns formed of a particular material (e.g., a polyester material, a relatively inelastic material, or a relatively elastic material such as elasticated yarns, a thermoplastic material), by selecting yarns of a particular size (e.g., denier), and/or a combination thereof. Using a knit construction may also provide desirable aesthetic characteristics by incorporating yarns having different colors, textures, or other visual properties arranged in a particular pattern. The yarns themselves and/or the knit structure formed by one or more of the yarns may be varied at different locations such that the knitted upper may have different properties, as described herein.

The yarns in accordance with aspects herein may be different types of yarns. For example, monofilament yarns and/or multifilament yarns formed from a variety of materials, including natural or synthetic materials, including polyethylene terephthalate (PET) yarns (commonly known as polyester), recycled PET yarns, and elastane yarns, can be used. In some aspects, the yarns may be generally described or designated as high-melting yarns or low-melting yarns. Herein, the term “high-melting” generally refers to yarns at least partially formed of material that melts or softens at a particular elevated temperature, e.g., a temperature that is between about 175-200 degrees Celsius, or higher, in certain aspects. High-melting thermoplastic yarns can include high-melting PET yarns, high-melting recycled PET yarns, cushioning yarns, core/sheath yarns in which the core comprises a high-melting material (e.g., a high-melting PET core) and the sheath comprises a low-melting material, elastane yarns, and/or other high-melting synthetic, thermoplastic yarns. Low-melting yarns can include low-melting thermoplastic yarns. Herein, the term “low-melting” generally refers to yarns at least partially formed of material that melts or softens at a temperature that is lower than high-melting yarns, e.g., a temperature that is between about 60-170 degrees Celsius, or less, in certain aspects. For example, low-melting yarns can partially or entirely be formed from materials that melt or soften at about 50 degrees Celsius to about 70 degrees Celsius; from about 55 degrees Celsius to about 65 degrees Celsius; or at about 60 degrees Celsius, in aspects. In aspects herein, low-melting yarns can be selected so that their low-melting material melts or softens at a temperature that is at least about 10-150 degrees Celsius less than that of the associated high-melting yarn(s) that are also incorporated into a knit element. In other words, low-melting yarns and high-melting yarns in a knit element can be selected so that a particular differential in melting/softening temperature is present. Low-melting thermoplastic yarns can include a synthetic polymeric material formed from a polymer that melts at relatively lower temperatures, e.g., less than 160 degrees Celsius in particular aspects. In example aspects, low-melting yarns can be entirely formed from a low-melting thermoplastic material such as low-melting PET or low-melting polyamide. The term “fusible yarn” may be used herein to describe these types of yarns.

In some aspects, one or more yarns having material with a lower-melting temperature relative to other yarns is incorporated and at least partially melted or softened after knitting. Such “low-melting yarn” may comprise a polymer having a relatively low melting temperature (e.g., yarns that melt below 175 degrees Celsius), which may be a thermoplastic polymer material such as thermoplastic polyurethane (TPU). Low-melting yarns can include yarns having a high-melting thermoplastic core formed from, for example, high-melting PET, surrounded by a sheath of low-melting thermoplastic material such as TPU, thermoplastic polyethylene (TPE), and/or other synthetic polymeric materials having a lower melting point relative to high-melting materials. In an aspect, a low-melting sheath may be melted upon application of a temperature at or below 170 degrees Celsius, such as around 120 degrees Celsius, while the high-melting core remains intact. In example aspects, the melting temperature of the thermoplastic material may be sufficiently different from the melting temperature of the high-melting yarns such that the thermoplastic material of the low-melting yarns may be essentially completely melted without melting or adversely affecting (e.g., burning, charring, or singeing) the characteristics of the high-melting yarns.

Unless indicated otherwise, all measurements provided herein are taken when the upper and/or article of footwear is at standard ambient temperature and pressure (298.15 K and 100 kPa) and is in a resting (non-tensioned) state. As used herein, the terms “substantially” and “about” mean within ±5% of an indicated value.

FIGS. 1A and 1B respectively schematically depict a medial view and a lateral view of an example article of footwear 100 having an upper 110 and a sole structure 112 secured to the upper 110. A biteline 115 represents where the upper 110 meets the sole structure 112. The article of footwear 100 is shown in the form of an athletic shoe but other types of shoes (e.g., sandals, leisure shoes, and the like) are contemplated herein. The article of footwear 100 includes a forefoot region 114 (having a toe end 117), midfoot region 116, and a heel region 118 (having a heel end), a medial side 120, and a lateral side 122. The article of footwear 100 includes an ankle collar 124 having an opening 125 for receiving a wearer's foot, and a throat area 126, which may include a tongue and one or more fasteners, such as laces. Although not shown, aspects herein contemplate that the article of footwear 100 may include additional elements layered on top of the upper 110 including, for example, leather materials, synthetic leather materials, knitted or woven textiles, polymer skins, and the like. The additional elements may be positioned at discrete locations of the upper 110 including, for example, a toe area (e.g., a toe cap), the heel area (e.g., a heel counter), and the like.

In example aspects, the upper 110 includes a knitted component 130 that forms at least part of the upper 110. For example, the knitted component 130 may form at least part of the midfoot region 116 and at least part of the forefoot region 114 of the upper 110. The knitted component 130 may form all or substantially all of the upper 110 aside from additional pieces applied on top of or underneath the knitted component 130. In the example shown, the knitted component 130 forms the forefoot region 114, the midfoot region 116, and the heel region 118 of the upper 110. In some aspects, the knitted component 130 forms at least part or all of the tongue, but it is contemplated that the tongue may be partially or fully formed from another component that is secured to the knitted component 130.

The knitted component 130 includes a first knit zone 140 and second knit zone 150 with a greater knit density, or number of stitches per unit area, than the first knit zone 140. That is, the first knit zone 140 may have a first knit density while the second knit zone 150 has a second density that is greater than the first knit density. The first knit zone 140 may form at least part of the heel region 118 of the upper. In some aspects, the first knit zone 140 extends over a majority of the heel region 118 or substantially all of the heel region 118.

In some aspects, the first knit zone 140 also forms at least part of the midfoot region 116. In some aspects, the first knit zone 140 may extend around a heel region 118 from the medial side 120 to the lateral side 122. In such aspects, a seam may join lateral and medial portions of the first knit zone 140, or the first knit zone 140 may extend continuously around the heel region 118 from the medial side 120 to the lateral side 122 without interruption. In some aspects, the first knit zone extends from the midfoot region 116 on a lateral side 122 of the upper 110, through the heel region 118, and to the midfoot region 116 on a medial side 120 of the upper 110. Additionally, in some aspects, the first knit zone 140 extends continuously from the collar 124 to the biteline 115.

The second knit zone 150 is in a midfoot region 116, a forefoot region 114, or both. For example, in some aspects, the second knit zone 150 is in the midfoot region 116 and the forefoot region 114, and in some aspects, the second knit zone 150 is only in the forefoot region 114. Further, in some aspects, the second knit zone 150 may be in the midfoot region 116 but not the forefoot region 114. Where the second knit zone 150 is present in the forefoot region 114, the second knit zone 150 may extend over a majority of or substantially all of the forefoot region 114. In example aspects, the second knit zone 150 extends continuously from the midfoot region 116 on the medial side 120, through the forefoot region 114, and to the midfoot region 116 on the lateral side 122.

The relatively low knit density of the first knit zone 140 may be at least partly due to integrally knit openings in the knit structure of the first knit zone 140. In particular, the first knit zone 140 may be a knit mesh structure with a repeating sequence of integrally knit openings. In some aspects, the integrally knit openings in the first knit zone 140 may have a width of at least two wales. Further, in some aspects, the knit density of the first knit zone 140 may be no greater than half the density of the second knit zone 150. Example knit constructions of the first knit zone 140 and the second knit zone 150 are further described with respect to FIGS. 3A and 3B.

The low density of the first knit zone 140 may provide increased breathability to the upper 110, which may be particularly useful for indoor activities such as running on a treadmill. Additionally, with indoor activities, there may be less need for weatherization of the upper 110. The higher density of the second knit zone 150 may provide increased structure and containment around a wearer's foot, which is particularly useful in areas where the wearer is likely to strike, such as the forefoot region 114 and, in some cases, the midfoot region 116. Treadmill running is more linear than other types of running or movement, so that this more focused containment pattern in the upper 110 may be sufficient to the wearer. In this way, the varied densities of the first knit zone 140 and the second knit zone 150 provides additional containment where needed while allowing increased breathability.

At least the first knit zone 140 (and in some aspects, the second knit zone 150) may comprise a single knit construction, which may increase breathability and weight of the upper 110. In some aspects, all or substantially all of the knitted component 130 has a single knit construction.

At least the first knit zone 140 may comprise a high-tenacity yarn, or a yarn having a tenacity of at least 5 grams per denier. The high-tenacity yarn in the first knit zone 140 increases the strength of the knit structure, which may be particularly useful for a more open structure like a knit mesh. In some aspects, the first knit zone 140 and the second knit zone 150 comprise a high-tenacity yarn. Additionally, in some aspects, at least the first knit zone 140 may also include a lower-melting yarn having a lower melting temperature than the high-tenacity yarn. The lower-melting yarn may be plated with the high-tenacity yarn. In some aspects, the lower-melting yarn is at least partially melted upon application of heat and/or pressure to the knitted component 130 after knitting, but the melted polymer material may not form a continuous film, in and of itself, over the knitted component 130.

In aspects herein, a low-melting yarn having a lower melting temperature is integrated adjacent to a high-tenacity yarn having a higher melting temperature. For instance, a yarn comprising a core/sheath configuration in which a core of a high-melting thermoplastic material is surrounded by a sheath of a low-melting thermoplastic material may be used in such a configuration. In other aspects, a multi-component yarn, e.g., one having a high-melting thermoplastic material and a low-melting thermoplastic material, may have other configurations, such as a side-by-side configuration in which a low-melting thermoplastic material is positioned in a side-by-side configuration with the high-melting thermoplastic material, a trilobal configuration, and the like. More broadly, in aspects herein, yarns may include a bi-component or multi-component configuration such that two or more materials are combined into a single yarn configuration that allows properties of the separate materials to be incorporated into a common yarn.

FIG. 2 depicts the knitted component 130 in a laid flat form prior to folding the knitted component 130 into a shape suitable for the upper 110. The knitted component 130 may be an integrally knit, unitary piece such that the knitted component 130 may be formed in a single knitting process. The knitted component 130 depicted in FIG. 2 has a generally U-shaped configuration that is outlined by an outer perimeter edge 210, a pair of heel edges 212, and an inner perimeter edge 214. In some aspects, the knitted component 130 is knit to the shape depicted in FIG. 2. Alternatively, the knitted component 130 may be knit as part of a larger textile piece and removed (e.g., via cutting) from the larger textile piece after knitting. FIG. 2 depicts the knitted component 130 without a tongue. In this example, a separate tongue component may be added to the knitted component 130. Alternative examples of the knitted component 130 include an integrally knit tongue. Further, the U-shaped configuration depicted in FIG. 2 is just one example shape of the knitted component 130 and other example shapes are contemplated herein.

In various aspects, the first knit zone 140 directly abuts the second knit zone 150 on the medial side 120 and/or the lateral side 122 of the knitted component 130. In the example of FIG. 2, the first knit zone 140 abuts the second knit zone 150 on the medial side 120 along a first boundary 202 and on the lateral side 122 along a second boundary 204. The first knit zone 140 and the second knit zone 150 of the knitted component 130 may be integrally knit such that the first boundary 202 and the second boundary 204 represent seamless transitions between the first knit zone 140 and the second knit zone 150.

In some aspects, the first boundary 202 and/or the second boundary 204 extend across the width of their respective side. For example, the first boundary 202 may extend from the outer perimeter edge 210 on the medial side 120 to the inner perimeter edge 214, which may form an eyestay area, on the medial side 120, and the second boundary 204 may extend from the outer perimeter edge 210 on the lateral side 122 to the inner perimeter edge 214, which may form an eyestay area, on the lateral side 122.

Additionally, the first boundary 202 and/or the second boundary 204 may extend diagonally. FIG. 2, for instance, depicts the end of the second boundary 204 adjacent the outer perimeter edge 210 being more rearward than the opposite end of the second boundary 204 adjacent the inner perimeter edge 214. As such, when the knitted component 130 is incorporated into the upper 110 and secured to a sole structure 112, the higher density of the second knit zone 150 may extend further rearward towards the biteline 115 than towards the throat area 126 on the lateral side 122, which may provide increased containment towards a bottom of a wearer's foot. In some aspects, the first boundary 202 may also extend diagonally. FIG. 2, for instance, depicts the end of the first boundary 202 adjacent the inner perimeter edge 214 being more rearward than the end of the first boundary 202 adjacent the outer perimeter edge 210. In some aspects where the first boundary 202 is an angle relative to the width of the knitted component 130, the first boundary 202 may be angled with respect to the width to a smaller degree than the second boundary 204. Turning back to FIGS. 1A and 1B, the angle 206 between the first boundary 202 at the biteline 115 on the medial side 120 is less than the angle 208 between the second boundary 204 and the biteline 115 on the lateral side 122.

Further, in some aspects, the first boundary 202 and the second boundary 204 are offset from one another along the longitudinal direction of the knitted component 130. For example, the first boundary 202 is positioned closer to the heel end 119 than the second boundary 204. In this way, the second knit zone 150 with the greater knit density extends further rearward on the medial side 120 than on the lateral side 122. This configuration increases containment and support to the wearer's arch where needed on the medial side 120 and increases breathability from the first knit zone 140 on the lateral side 122.

The knitted component 130 includes an overfoot portion 220 configured to extend over the wearer's foot, and in some aspects, the knitted component 130 also includes an underfoot portion 222 configured to extend under a wearer's foot. The underfoot portion 222 may be positioned below the biteline 115 when the knitted component 130 is formed into the article of footwear 100 with the sole structure 112. The underfoot portion 222 may be secured to the sole structure 112. This underfoot portion 222 may be used instead of a traditional strobel.

In the configuration shown in FIG. 2, the underfoot portion 222 is split between the medial side 120 and the lateral side 122 after knitting. When the upper 110 is formed from the knitted component 130, the two underfoot portions 222 may be joined through at least one of stitching, embroidery, bonding, adhesives, and the like. Further details about the underfoot portion 222 are described with respect to FIG. 4.

FIGS. 3A and 3B depict example stitch notation diagrams that may be used to form the knitted component 130. FIG. 3A depicts an example stitch notation diagram 300 that may be used for the first knit zone 140, and FIG. 3B depicts an example stitch notation diagram 350 that may be used for the second knit zone 150. Each of the stitch notation diagrams 300 and 350 includes rows (rows 352, 354, 356, and 358 in FIG. 3A and rows 302, 304, 306, and 308 in FIG. 3B) that each include representations of needles on front and back needle beds of a knitting machine. Each of these rows may represent a pass of a feeder of the knitting machine. Some of these rows may be formed together such that they represent courses of multiple yarns knit to form the same course, either on a single bed or both beds, as further described below. It should be understood that the stitch notation diagrams 300 and 350 are intended to be representative of the general knitting patterns used in forming the first knit zone 140 and the second knit zone 150, and that additional rows and needle positions may be utilized following such patterns. Additionally, references to back needle bed and front needle bed should be understood to be illustrative for relative positioning and that courses described on the back needle bed may be formed on the front needle bed while courses on the front needle bed may be formed on the back.

Each of the stitch notation diagrams 300 and 350 depict a first yarn 310 and a second yarn 312. The first yarn 310 and the second yarn 312 may have one or more different material properties. For example, the first yarn 310 may be a high-melting yarn, and the second yarn 312 may be a low-melting yarn in that the second yarn 312 may comprise a thermoplastic polymer having a lower melting temperature than the melting or deformation temperature of the first yarn 310. In this way, an amount of heat may be applied to a knitted component knit in accordance with diagrams 300 or 350 (e.g., the knitted component 130) that is sufficient to at least partially melt the second yarn 312 while the first yarn 310 may be unmelted and retain its interlooped structure. In some aspects, the second yarn 312 comprises a single component monofilament having the thermoplastic polymer. Additionally or alternatively, the first yarn 310 may have a greater tenacity than the second yarn 312. In some aspects, the first yarn 310 may have a tenacity that is at least 5 grams per denier. In some aspects, the first yarn 310 is a PET yarn having a tenacity of at least 5 grams per denier, and the second yarn 312 is a thermoplastic polyurethane monofilament.

The stitch notation diagram 300 of FIG. 3A is an example diagram for creating a knit mesh structure that may be used for the first knit zone 140. In particular, the pattern shown in the diagram 300 may result in a half-gauge, single-knit construction with integrally knit openings. Additionally, the diagram 300 represents a knit construction of the first yarn 310 knit in rows 304 and 308, and a second yarn 312 knit in rows 302 and 306. The first yarn 310 and the second yarn 312 are separated into different sets of rows in the diagram 300 because they may be fed through different feeders, but one row of each yarn 310 and 312 (e.g., rows 302 and 304) may both be knit before the yarns 310 and 312 are released from the needles. In this way, the first yarn 310 and the second yarn 312 may be knit along the same course.

The first yarn 310 is knit in rows 304 and 308 in a half-gauge. That is, the first yarn 310 is knit only on every other needle on the back needle bed. Additionally, every fourth knit stitch formed on the back needle bed is transferred, creating integrally knit openings. The transferring stitch (e.g., stitch 316) is moved to an adjacent knit stitch (e.g., stitch 318), and because the first yarn 310 is only knit in half-gauge, this transfer to the next adjacent knit stitch requires a two-needle transfer. That is, the transferring stitch 316 is moved two needle positions in one direction, such as to the right). As a result, an opening 320 spanning three needle positions is created. Arrow 322 represents the transfer of transferring stitch 316.

To alleviate tension from the transfer and prevent breakage, additional length of the first yarn 310 may be incorporated into the knit structure. For example, after the transferring stitch 316 is knit, an additional stitch 328 is knit. This additional stitch 328, also referred to herein as a drop stitch, is knit at the needle position that is immediately adjacent the transferring stitch 316, which would otherwise be skipped if doing a simple half-gauge knit. After row 304 is knit, the transfer steps occur, which includes moving the transferring stitch 316 to the front needle bed as shown by arrow 324, dropping the drop stitch 328 as shown by drop notation 326, and transferring the transferring stitch 316 back to the back needle bed and over two needle positions as shown by arrow 322. Dropping the drop stitch 328 creates additional, unlooped length of the first yarn 310 that may allow the transferring stitch 316 to be moved without risking breakage due to increased tension in the first yarn 310. Additionally, a sinking technique may be performed at needles associated with the transferring stitch 316 and with the receiving stitch 318 to create additional length of the first yarn 310.

The second yarn 312 may be knit according to a different sequence. The second yarn 312 forms either a knit stitch 332 or a tuck stitch 334 at every fourth needle position, which corresponds to the needle positions defining each side of the opening described above made by the first yarn 310. The knit stitches 332 and the tuck stitches 334 of the second yarn 312 alternate needle positions in adjacent courses. For example, row 302 represents a first course knit with the second yarn 312, and row 306 represents a second course knit with the second yarn 312; the knit stitches 332 in row 302 are aligned with the tuck stitches 334 in row 304 and vice versa.

Turning to FIG. 3B, the stitch notation diagram 350 is an example diagram for creating a knit structure that may be used for the second knit zone 150. In particular, the pattern shown in the diagram 350 may result in a half-gauge, single-knit construction. Similar to diagram 300, the diagram 350 represents a knit construction of the first yarn 310 knit in rows 354 and 358, and a second yarn 312 knit in rows 352 and 356. The first yarn 310 and the second yarn 312 are separated into different sets of rows in the diagram 350 because they may be fed through different feeders, but one row of each yarn 310 and 312 (e.g., rows 352 and 354) may both be knit before the yarns 310 and 312 are released from the needles. In this way, the first yarn 310 and the second yarn 312 may be knit along the same course.

The first yarn 310 is knit in rows 354 and 358 and is knit with knit stitches 336 on every other needle (i.e., half-gauge) of the same needle bed, which is the back needle bed in this case. The second yarn 312 knit in rows 352 and 356 may be knit in accordance with the same sequence of the second yarn 312 in diagram 300. Therefore, details need not be repeated here. Although it is contemplated that aspects may include the second yarn 312 being knit with different sequences in the first knit zone 140 and the second knit zone 150 in alternative aspects.

Because the first yarn 310 and the second yarn 312 are knit only on one needle bed in diagram 350, the resulting knit construction is a single knit construction. As such, the second knit zone 150 may have a single knit construction. Additionally, in the diagram 300 in FIG. 3A, the first yarn 310 and the second yarn 312 are generally knit on only one needle bed (here, the back needle bed). Diagram 300 does depict the drop stitches 328 of the first yarn 310 being knit on the front needle bed, but because those stitches are dropped as described herein, loops corresponding to such stitches in the diagram 300 are not formed. Therefore, the resulting knit structure from diagram 300 has a single knit construction. As such, the first knit zone 140 may also have a single knit construction.

FIG. 4 depicts a view of the upper 110 of the article of footwear 100 without the sole structure 112 to show an underfoot portion 422 of the upper 110. The underfoot portion 422 of the upper 110 may include a composite structure 402 that includes a portion of the knitted component 130 (e.g., the underfoot portion 222 of the knitted component 130) and a thermoplastic film layer 404. In some aspects, the thermoplastic film layer 404 comprises a thermoplastic polyurethane material.

The composite structure 402 may extend continuously along the underfoot portion 422 through the forefoot region 114, the midfoot region 116, and the heel region 118 of the upper 110. The composite structure 402 may include portions of both the first knit zone 140 and the second knit zone 150. The composite structure 402 may be used on the underfoot portion 422 to help bond the upper 110 to the sole structure 112 in FIGS. 1A and 1B. In particular, the thermoplastic film layer 404 provides additional surface area for bonding than what would be afforded with only the knitted component 130 of the upper 110, which may create a more secure bond between the upper 110 and the sole structure 112. The increase of additional surface area may be particularly beneficial for an open knit structure, such as the first knit zone 140.

In some aspects, the composite structure 402 in the midfoot region 116 and the heel region 118 may generally be confined to the underfoot portion 422. That is, the composite structure 402 may be generally below the biteline 115 in the midfoot region 116 and the heel region 118 when the sole structure 112 is secured to the upper 110. Further, in some aspects, the composite structure 402 extends to an overfoot portion 420 of the upper 110 in at least part of the forefoot region 114. In particular, the composite structure 402 may extend above the biteline 115 at the toe end 117 when the sole structure 112 is secured to the upper 110. In this way, the composite structure 402 may provide additional durability and weatherization to the toe end 117.

In some aspects, the thermoplastic film layer 404 is generally positioned interior to the knitted component 130. That is, when the composite structure is formed, the thermoplastic film layer 404 may be arranged adjacent the side of the knitted component 130 that will be an interior-facing side when the knitted component 130 is formed into the upper 110. Heat and/or pressure may be applied to the knitted component 130 and thermoplastic film layer 404 to cause the thermoplastic film layer 404 to at least partially flow through to the opposite side (exterior-facing side) of the knitted component 130.

FIGS. 5A and 5B provide partial example cross-sections to schematically depict this arrangement of the knitted component 130 and the thermoplastic film layer 404 in the composite structure 402. In both examples, the thermoplastic film layer 404 is arranged interior to the knitted component 130, but the cross-sections 500 and 550 differ in that the thermoplastic film layer extends through the knitted component 130.

The cross-sections 500 and 550 both depict the thermoplastic film layer 404 forming the interior-facing surface 502 of the composite structure 402. The thermoplastic polymer material of the thermoplastic film layer 404 at least partially encapsulates the knitted component 130. In particular, the thermoplastic polymer material may at least partially extend through openings within the knit structure, which may be either integrally formed openings or openings inherent in any knitted loop structure. Cross-sections 500 and 550 also both depict the knitted component 130 having different knit densities, which may represent the first knit zone 140 and the second knit zone 150.

The yarn of the knitted component 130 depicted in FIGS. 5A and 5B may be the first yarn 310 described with respect to FIGS. 3A and 3B. In some aspects, the knitted component 130 includes the second yarn 312. Further, in some aspects, the knitted component 130 may include the second yarn 312 only prior to application of heat and/or pressure because the second yarn 312 may melt and become part of the thermoplastic film layer 404 upon heat and/or pressure. In this way, the thermoplastic film layer 404 may include multiple thermoplastic polymer components, such as a thermoplastic polymer component from what was a separate film applied to the knitted component 130 and a thermoplastic polymer component from the second yarn 312 knit into the knitted component 130.

The example cross-section 500 of FIG. 5A depicts the thermoplastic film layer 404 extending from the interior-facing surface 502 to the opposite side of the knitted component 130. In this way, the exterior-facing surface 504 of the composite structure 402 may comprise portions of the yarn of the knitted component 130 and the thermoplastic film layer 404. The example cross-section 550 of FIG. 5B depicts the thermoplastic film layer 404 extending from the interior-facing surface 502 to beyond the knitted component 130 so that the exterior-facing surface 504 of the composite structure 402 may comprise the thermoplastic film layer 404 without the yarn of the knitted component 130. In at least some examples, the thermoplastic film layer 404 may still be more interiorly positioned to the knitted component 130 in that the thickness 506 of the thermoplastic film layer 404 exterior to the knitted component 130 may be less than the thickness 508 of the thermoplastic film layer 404 interior to the knitted component 130. This difference in thickness may be at least partially due to the thermoplastic film layer 404 being arranged adjacent the interior surface of the knitted component 130 prior to application of heat and/or pressure to create the composite structure 402.

Cross-sections 500 and 550 also depict the sole structure 112 adjacent to the exterior-facing surface 504 of the composite structure 402. The composite structure 402 may be bonded to the sole structure 112. Because openings in the knitted component 130 are at least partially filled with the thermoplastic film layer 404 on the exterior-facing surface 504, there may be more material for the sole structure 112 to join with compared to being secured to the knitted component 130 alone. In some cases, the composite structure 402 may provide a more continuous surface area on the exterior-facing surface 504 to which the sole structure 112 may bond. Additionally, the more interior arrangement of the thermoplastic film layer 404 relative to the knitted component 130 may strengthen the attachment between the sole structure 112 and the upper 110. Having the thermoplastic film layer 404 extend through the knitted component 130 to bond with the sole structure 112 ensures more (and in some cases all) of the knitted component 130 is encapsulated by the thermoplastic film layer 404 and more directly secured to the sole structure 112.

The following clauses represent example aspects of concepts contemplated herein. Any one of the following clauses may be combined in a multiple dependent manner to depend from one or more other clauses. Further, any combination of dependent clauses (clauses that explicitly depend from a previous clause) may be combined while staying within the scope of aspects contemplated herein. The following clauses are examples and are not limiting.

Clause 1: An article of footwear comprising: an upper comprising a knitted component and including: a first knit zone in a heel region of the upper, the first knit zone having a first knit density; and a second knit zone integrally knit with the first knit zone and in a midfoot region of the upper, the second knit zone having a second knit density that is greater than the first knit density.

Clause 2: The article of footwear of clause 1, wherein the first knit zone extends from the midfoot region on a lateral side of the upper, through the heel region, and to the midfoot region on a medial side of the upper.

Clause 3: The article of footwear of any of clauses 1-2, further comprising a sole structure secured to the upper, wherein the first knit zone extends continuously from a collar to a biteline wherein the sole structure meets the upper.

Clause 4: The article of footwear of any of clauses 1-3, wherein the second knit zone is also within a forefoot region of the upper.

Clause 5: The article of footwear of any of clauses 1-4, wherein the second knit zone extends continuously from the midfoot region on a medial side of the upper, through the forefoot region, and to the midfoot region on a lateral side of the upper.

Clause 6: The article of footwear of any of clauses 1-5, wherein the first knit density is no more than half of the second knit density.

Clause 7: The article of footwear of any of clauses 1-6, wherein the knitted component comprises a single layer knit construction in the first knit zone and the second knit zone.

Clause 8: The article of footwear of any of clauses 1-7, wherein the first knit zone comprises a course of a first yarn comprising a tenacity of at least 5 grams per denier.

Clause 9: The article of footwear of clause 8, wherein, in at least the first knit zone, the first yarn is plated with a second yarn having a lower melting temperature than the first yarn.

Clause 10: The article of footwear of any of clauses 1-9, wherein the first knit zone comprises a mesh structure having integrally knit openings having a width of at least two wales.

Clause 11: An article of footwear comprising: a sole structure; and an upper secured to the sole structure, the upper comprising a composite structure extending underfoot and secured to the sole structure, the composite structure comprising: a knit mesh component on an outer-facing surface of the composite structure and having a plurality of integrally knit openings; and a thermoplastic film layer on an inner-facing surface of the composite structure, the thermoplastic film layer extending partially to the outer-facing surface of the composite structure, wherein the sole structure is bonded to the knit mesh component and the thermoplastic film layer of the composite structure.

Clause 12: The article of footwear of clause 11, wherein the composite structure extends continuously through a forefoot region, a midfoot region, and a heel region of the upper.

Clause 13: The article of footwear of any of clauses 11-12 further comprising a biteline where the sole structure meets the upper, and wherein the composite structure extends above the biteline in at least part of the forefoot region and maintains below the biteline in the midfoot region and the heel region.

Clause 14: The article of footwear of any of clauses 11-13, wherein the upper comprises an integrally knitted component comprising a first knit zone having a first knit density and a second knit zone having a second knit density that is greater than the first knit density, wherein the composite structure comprises a portion of the integrally knitted component in the first knit zone and a portion of the integrally knitted component in the second knit zone, wherein the integrally knitted component in at least one of the first knit zone or the second knit zone comprises the knit mesh component of the composite structure.

Clause 15: The article of footwear of clause 14, wherein the first knit zone extends around a heel region of the upper and the second knit zone abuts the first knit zone.

Clause 16: An article of footwear comprising: an upper comprising a knitted component and including: a first knit zone in a heel region of the upper, the first knit zone having a first knit density; a second knit zone integrally knit with the first knit zone and in a midfoot region of the upper, the second knit zone having a second knit density different than the first knit density; and a first boundary between the first knit zone and the second knit zone on a medial side of the upper and a second boundary between the first knit zone and the second knit zone on a lateral side of the upper, wherein the first boundary is closer to a heel end of the upper than the second boundary.

Clause 17: The article of footwear of clause 16, further comprising a sole structure secured to the upper, a biteline being where the upper meets the sole structure.

Clause 18: The article of footwear of clause 17, wherein the first boundary forms a first angle with the biteline along the second knit zone, and the second boundary forms a second angle with the biteline along the second knit zone, the first angle being less than the second angle.

Clause 19: The article of footwear of any of clauses 17-18, wherein the first boundary and the second boundary both extend continuously from the biteline to an eyestay area of the upper.

Clause 20: The article of footwear of any of clauses 11-19, further comprising a composite structure extending underfoot and comprising a thermoplastic film layer at least partially encapsulating a portion of the knitted component in the first knit zone and a portion of the knitted component in the second knit zone.

Aspects of the present disclosure have been described with the intent to be illustrative rather than restrictive. Alternative aspects will become apparent to those skilled in the art that do not depart from its scope. A skilled artisan may develop alternative means of implementing the aforementioned improvements without departing from the scope of the present disclosure.

It will be understood that certain features and subcombinations are of utility and may be employed without reference to other features and subcombinations and are contemplated within the scope of the claims. Not all steps listed in the various figures need be carried out in the specific order described.