Patent Publication Number: US-2023151516-A1

Title: Upper For An Article of Footwear Having Two Yarn Types

Description:
RELATED APPLICATION 
     This application is a continuation of and claims the benefit of U.S. application Ser. No. 17/144,368, filed Jan. 8, 2021, which claims the benefit of U.S. Provisional Patent Application No. 62/958,493, filed Jan. 8, 2020, both of which are incorporated by reference herein in their entireties. 
    
    
     BACKGROUND 
     Conventional articles of footwear generally include two primary elements: an upper and a sole structure. The upper is generally secured to the sole structure and may form a void within the article of footwear for comfortably and securely receiving a foot. The sole structure is generally secured to a lower surface of the upper so as to be positioned between the upper and the ground. In some articles of athletic footwear, for example, the sole structure may include a midsole and an outsole. The midsole may be formed from a polymer foam material that attenuates ground reaction forces to lessen stresses upon the foot and leg during walking, running, and other ambulatory activities. The outsole may be secured to a lower surface of the midsole and may form a ground-engaging portion of the sole structure that is formed from a durable and wear-resistant material. 
     The upper of the article of footwear generally extends over the instep and toe areas of the foot, along the medial and lateral sides of the foot, and around the heel area of the foot and in some instances under the foot. Access to the void in the interior of the upper is generally provided by an ankle opening in and/or adjacent to a heel region of the footwear. A lacing system is often incorporated into the upper to adjust the fit of the upper, thereby facilitating entry and removal of the foot from the void within the upper. In addition, the upper may include a tongue that extends under the lacing system to enhance adjustability of the footwear, and the upper may incorporate other structures such as, for example, a heel counter to provide support and limit movement of the heel. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The embodiments of the present disclosure may be better understood with reference to the following drawings and description. The components in the figures are not necessarily to scale, with emphasis instead being placed upon illustrating the principles of the present disclosure. Moreover, in the figures, like referenced numerals designate similar or identical features. 
         FIG.  1    is an illustration showing a lateral side of an article of footwear having a stretch resistance system in accordance with certain aspects of the present disclosure. 
         FIG.  2    is an illustration showing a medial side of the article of footwear of  FIG.  1    in accordance with certain aspects of the present disclosure. 
         FIG.  3    is an illustration showing a knitted component forming an upper for the article of footwear of  FIG.  1    in accordance with certain aspects of the present disclosure. 
         FIG.  4    is an illustration showing a portion of the knitted component of  FIG.  3    in accordance with certain aspects of the present disclosure. 
         FIG.  5    is an illustration showing a portion of another embodiment of a knitted component forming an upper for an article of footwear having a stretch resistance system in accordance with certain aspects of the present disclosure. 
         FIG.  6    is an illustration showing a portion of another embodiment of a knitted component forming an upper for an article of footwear having a stretch resistance system in accordance with certain aspects of the present disclosure. 
     
    
    
     DETAILED DESCRIPTION 
     Various aspects are described below with reference to the drawings in which like elements generally are identified by like numerals. The relationship and functioning of the various elements of the aspects may better be understood by reference to the following detailed description. However, aspects are not limited to those illustrated in the drawings or explicitly described below. It also should be understood that the drawings are not necessarily to scale, and in certain instances details may have been omitted that are not necessary for an understanding of aspects disclosed herein, such as conventional fabrication and assembly. 
     Certain aspects of the present disclosure relate to uppers configured for use in an article of footwear and/or other articles, such as articles of apparel. When referring to articles of footwear, the disclosure may describe basketball shoes, running shoes, biking shoes, cross-training shoes, football shoes, golf shoes, hiking shoes and boots, ski and snowboarding boots, soccer shoes, tennis shoes, and/or walking shoes, as well as footwear styles generally considered non-athletic, including but not limited to dress shoes, loafers, and sandals. 
       FIGS.  1 - 2    are illustrations showing an example of an article of footwear  100  having an upper  102  that is secured to a sole structure  104 . The area where the sole structure  104  joins the upper  102  may be referred to as a biteline  106 . The upper  102  may be at least partially formed by a knitted component  108 , and be joined to the sole structure  104  in a fixed manner using any suitable technique, such as through the use of an adhesive, by sewing, etc. The sole structure  104  may define the bottom surface of a void  109  for receiving and accommodating a user&#39;s foot, and the upper  102  may define the sides of the void  109 . 
     At least a portion of the upper  102  may be formed with a knitted component  108  (or another suitable textile component). For example, the upper  102  may be formed primarily as an integral one-piece element during a knitting process, such as a weft knitting process (e.g., with a flat knitting machine or circular knitting machine), a warp knitting process, or any other suitable knitting process. That is, the knitting process on the knitting machine may substantially form the knit structure of the knitted components without the need for significant post-knitting processes or steps. Alternatively, the knitted component  108  may be formed separately as distinct integral one-piece elements and then the respective elements attached (e.g., via sewing). 
     Referring to  FIG.  3   , which shows the knitted component  108  as it may appear after knitting but prior to being manipulated into a wearable shape to form the upper  102 . The upper  102  may include a lateral side  110  and a medial side  112 . A throat area  114  may be included between the lateral side  110  and the medial side  112 , and the throat area  114  may be positioned to cover the top (dorsal) surface of the foot during typical use. The throat area  114  may include a lateral side  115  and a medial side  117 . The lateral side  115  of the throat area  114  is disposed adjacent to the lateral side  110  of the upper  102  and the medial side  117  of the throat area  114  is disposed adjacent to the medial side  112  of the upper  102 . A midfoot area  116  of the upper  102  may be located between a heel area  118  and a toe area  120 . The throat area  114  may be primarily located in the midfoot area  116 . In some embodiments, an optional tongue may be disposed at least partially in the throat area  114 . 
     Forming the upper with a knitted component  108  may impart advantageous characteristics including, but not limited to, a particular degree of elasticity (for example, as expressed in terms of Young&#39;s modulus), breathability, bendability, strength, moisture absorption, weight, abrasion resistance, and/or a combination thereof. These characteristics may be accomplished by selecting a particular single layer or multi-layer knit structure (e.g., a ribbed knit structure, a single jersey knit structure, or a double jersey 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 spandex), by selecting yarns of a particular size (e.g., denier), and/or a combination thereof. The weight of the upper  102 , and thus the overall weight of the article of footwear  100 , may be reduced with respect to alternative uppers and/or other components that are typically used in footwear. The knitted component  108  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 of the knitted components may be varied at different locations to provide different knit portions with different properties (e.g., a portion forming the throat area  114  of the knitted component  108  may be relatively elastic while a portion forming the heel area  118  or another area may be relatively inelastic, or vice versa). 
     In some embodiments, the knitted component  108  may incorporate one or more materials with properties that change in response to a stimulus (e.g., temperature, moisture, electrical current, magnetic field, or light). For example, the knitted component  108  may include yarns formed of a thermoplastic polymer material (e.g., a polyurethane, polyamide, polyolefin, and/or nylon) that transitions from a solid state to a softened or liquid state when subjected to certain temperatures at or above its melting point and then transitions back to the solid state when cooled. The thermoplastic polymer material may provide the ability to heat and then cool a portion of the knitted component  108  to thereby form an area of bonded or continuous material (herein referred to as a “fused area”) that exhibits certain advantageous properties including a relatively high degree of rigidity, strength, and water resistance, for example. 
     At least one of the yarns incorporated into the knitted component  108  may be what is referred to as a “high-tenacity” yarn, which may be particularly advantageous when it is desired for the margins to exhibit enhanced strength. For example, as described in more detail below (and shown in certain following figures), the and second yarn  122  the third yarn  124  incorporated into the knitted component  108  may require enhanced strength relative to typically-used yarns to prevent yarn breakages during knitting. As used herein, “tenacity” is understood to refer to the amount of force (expressed in units of weight, for example: pounds, grams, centinewtons or other units) needed to rupture a yarn (i.e., the breaking force or breaking point of the yarn), divided by the linear mass density of the yarn expressed, for example, in (unstrained) denier, decitex, or some other measure of weight per unit length. The amount of force needed to break a yarn (the “breaking force” of the yarn) is determined by subjecting a sample of the yarn to a known amount of force by stretching the sample until it breaks, for example, by inserting each end of a sample of the yarn into the grips on the measuring arms of an extensometer, subjecting the sample to a stretching force, and measuring the force required to break the sample using a strain gauge load cell. Suitable testing systems can be obtained from Instron (Norwood, MA, USA). Yarn tenacity and yarn breaking force are distinct from burst strength or bursting strength of a textile, which is a measure of the maximum force that can be applied to the surface of a textile before the surface bursts. 
     Generally, in order for a yarn to withstand the forces applied in an industrial knitting machine, the minimum tenacity required is approximately 1.5 grams per denier (g/D). Most synthetic polymer continuous filament yarns formed from commodity polymeric materials generally have tenacities in the range of about 1.5 g/D to about 4 g/D. The term “about” is specifically defined herein to include the specific value referenced as well as a dimension that is within 5% of the dimension both above and below the dimension. For example, polyester filament yarns that may be used in the manufacture of knit uppers for article of footwear have tenacities in the range of about 2.5 g/D to about 4 g/D. Filament yarns formed from commodity synthetic polymeric materials which are considered to have high tenacities (e.g., a “high tenacity yarn”) generally have tenacities in the range of about 5 g/D to about 10 g/D. For example, commercially available package dyed polyethylene terephthalate filament yarn from National Spinning (Washington, N.C., USA) has a tenacity of about 6 g/D, and commercially available solution dyed polyethylene terephthalate filament yarn from Far Eastern New Century (Taipei, Taiwan) has a tenacity of about 7 g/D. Filament yarns formed from high performance synthetic polymer materials generally have tenacities of about 11 g/D or greater. For example, filament yarns formed of aramid typically have tenacities of about 20 g/D, and filament yarns formed of ultra-high molecular weight polyethylene (UHMWPE) having tenacities greater than 30 g/D are available from Dyneema (Stanley, N.C., USA) and Spectra (Honeywell-Spectra, Colonial Heights, Va., USA). 
     Herein, yarns referred to as “high tenacity yarns” are those having a tenacity of at least 5 g/D, such as at least 10 g/D, and such as at least 20 g/D in certain embodiments. High tenacity yarns may be selectively located in areas of the upper  102  where high-strength and high-durability is desirable. For example, referring to  FIG.  4   , the lateral side  115  of the throat area  114  and/or the medial side  117  of the throat area  114  (including a second area  126  that extends through at least one of the lateral side  115  and the medial side  117  of the throat area  114 ) may include a plurality of second knit courses  128  formed by at least one high tenacity yarn (e.g., the second yarn  122 ). Optionally, a majority of the second knit courses  128  in the lateral side  115  of the throat area  114  and/or the medial side  117  of the throat area  114  may include at least one high tenacity yarn (e.g., the second yarn  122 ), such as all of (or a majority of) the second knit courses  128  that are located adjacent to one or more lace loops  130 . Further, to save on material costs and product weight, it is contemplated that the second knit courses  128  forming the lateral side  115  of the throat area  114  and/or the medial side  117  of the throat area  114  may substantially exclude other types of yarns (i.e., those that are not considered high tenacity yarns), but this is not required. 
     By contrast, the lateral side  110  and/or the medial side  112  of the upper  102  (e.g., located laterally and medially of the throat area  114 , respectively, including a first area  132  located on at least one of the lateral side  110  and the medial side  112  of the upper  102 ) may be primarily formed by a different yarn type (although, in other embodiments, a high tenacity yarn may be primarily used). For example, referring to  FIG.  3   , the lateral side  110  and/or the medial side  112  of the upper  102  may include a plurality of first knit courses  134  that are at least partially formed by a first yarn  136 . Optionally, a majority of the first knit courses  134  in the lateral side  110  and/or the medial side  112  of the upper  102  are at least partially formed by the first yarn  136 . The plurality of first knit courses  134 , when incorporated into an upper  102  of an article of footwear  100 , may form an exterior surface  152  and an interior surface  154  (facing the void  109 ) of the upper  102 . 
     The first yarn  136  may include a polyester material, a fusible material (e.g., a thermoplastic polymer material with a melting point suitable for post-knit heat processing), an elastic material (e.g., elastane), a recyclable material, and/or any other suitable material. The first yarn  136  and/or combination of yarns forming the lateral side  110  and/or the medial side  112  of the upper  102  ( FIG.  3   ) may be selected to provide the lateral side  110  and/or the medial side  112  of the upper  102  with a suitable stretchability and/or softness to provide comfort, for example. 
     In some embodiments (still referring to  FIG.  4   ), the first yarn  136  forming the first knit courses  134  of the lateral side  110  and/or the medial side  112  of the upper  102  may extend into the lateral side  115 /medial side  117  of the throat area  114  (e.g., it may be advantageous for the first yarn  136  to only be secured at the edge(s)  158  of the lateral side  115 /medial side  117  of the throat area  114  such that it is substantially excluded from the throat area  114 ), but this is not required. Likewise, the second yarn  122  (e.g., a high tenacity yarn) forming the second knit courses  128  of the lateral side  115  and/or medial side  117  of the throat area  114  may be substantially excluded from the areas outside the throat area  114 , but this is not required. In some embodiments (e.g., if both yarn types are isolated in their respective areas), an intarsia method may be used, where each yarn type is devoted to its own feeder, and where the respective yarn types are only secured (e.g., looped) at the boundary between the throat area  114  and the surrounding areas. For example, an intarsia method may be used that is similar or identical to that described in U.S. patent application Ser. No. 16/397,138, filed Apr. 29, 2019, which is hereby incorporated by reference in its entirety. 
     The lateral side  115  and/or medial side  117  of the throat area  114  may include one or more features configured (e.g., sized, located, and shaped) to receive a lacing element  131  and/or otherwise engage a footwear fastening system (such as a shoelace as shown, a cable system, a strap, etc.). In the depicted example, for example, the lateral side  115  and the medial side  117  of the throat area  114  both include knit anchors  138 , which in this instance include tubes or other suitable pathways between two lace loops  130  (e.g., for receipt of a shoelace). The knit anchors  138  may include one or more of the features described in U.S. patent application Ser. No. 16/534,702, filed on Aug. 7, 2019, which is hereby incorporated by reference in its entirety. For example, the knit anchors  138  may be formed by a tubular knitting process where a knit layer formed on a first needle bed of the knitting machine remains separable from (e.g., not locked to) a knit layer formed on a second needle bed for a plurality of courses (as described in more detail below). Thus, at least a portion of the lateral side  115  of the throat area  114  and/or the medial side  117  of the throat area  114  may include a two-layer structure formed by such tubular knitting, and it is contemplated that this two-layer structure (e.g., having a first layer and a second layer with a pocket therebetween) may extend along the throat area  114  at least the length where the lace loops  130  are located (and perhaps further). Alternatives are also contemplated (e.g., where the tubular knitting process is located to only certain knit anchors, and/or where a single layer knitting process is used along the throat area  114 , etc.). 
     For example, referring to  FIG.  4   , (showing a close-up view of one knit anchor  138 ) a first layer  140  of the anchor  138 , which may define the exterior surface  144  of the throat area  114 , may be formed on a first needle bed (e.g., with a single-jersey or similar knit structure). A second layer  142  of the anchor  138  (located beneath the first layer  140  from the perspective of  FIG.  4   ), which may define an inner surface  146  of the throat area  114 , may be formed on a second needle bed of a knitting machine (e.g., with a single-jersey or similar knit structure). Optionally, the tubular knit structure may extend through the entirety (or the majority) of the lateral side  115  and/or the medial side  117  of the throat area  114  (e.g., formed by the second knit courses  128 ). In such an embodiment, a pocket  139  may be formed between the first layer  140  and the second layer  142  and extends longitudinally (e.g., the direction of the wales; toe-to-heel direction) along the throat area  114  on one or both of the lateral and medial sides  115  and  117  of the throat area  114 . 
     Alternatively, the edges of the anchor  138  (which extend along the anchor&#39;s length) may be locations where a course at the end of the tubular knit structure (in the knitting direction) utilizes both needle beds, thus locking the first layer  140  and the second layer  142  together such that each anchor  138  is associated with its own separate pocket. In other embodiments, the knit anchor(s)  138  may simply be a hole/opening within one of the lateral side  115  and medial side  117  of the throat area  114  (e.g., a first opening  130   a  and a second opening  130   b  located in the first layer  140  of the lateral side  115  and/or the medial side  117  of the throat area  114 ), and the lateral side  115  and/or the medial side  117  of the throat area  114  may be formed without a pocket formed between layers as shown. The first and second openings  138   a  and  138   b  are configured to receive a fastening element  131 , such as a shoelace as shown in  FIG.  3   ). 
     To provide the lateral side  110  and/or the medial side  112  of the upper  102  with adequate strength and stretchability, one or more third yarns  124  may be included (and potentially knitted) in the lateral side  110  and/or the medial side  112  of the upper  102 , extending from the biteline  106  of the upper  102  to the lateral side  115  and/or the medial side  117  of the throat area  114 . The third yarn  124  may be a high tenacity yarn or a P16 yarn (e.g., a polyester yarn), and it is contemplated that the third yarn  124  may be a yarn that is the same or similar to the above-described second yarn  122 . In  FIG.  4   , the third yarn  124  includes a first knitted area  202  and a second knitted area  204  (and more or fewer knitted areas may be alternatively included). As shown, the first knitted area  202  and the second knitted area  204  each include four consecutive knitted loops  206 , but other configurations are alternatively contemplated. For example, the first knitted area  202  and/or the second knitted area  204  may include any suitable number of loops, such as at least four consecutive or alternating loops but less than twenty consecutive or alternating loops (e.g., to optimize and/or customize the overall stretchability of the medial side  112  of the upper  102 ). The size and location of the knitted areas  202  may have a particularly prominent effect on certain features of the medial side  112  of the upper  102  when the third yarn(s)  124  have a characteristic that is substantially different than the first yarns  136 . For example, when the third yarns  124  are high tenacity yarns but the first yarns  136  are not, the size and structure of the knitted areas  202 ,  204  may provide adequate and suitable stretchability, strength, and durability characteristics. 
     As shown, the third yarns  124  may include at least one floating portion  148  extending through at least one of the first knit courses  134  in the lateral side  110  and/or the medial side  112  of the upper  102  (and potentially providing a high-tenacity connection between the different knitted areas of high tenacity yarns, such as the first knitted area  202  and the second knitted area  204 ). The floating portion(s)  148  of the third yarn  124  that extend through the first knit course(s)  134  may span or extend along many wales of the knitted component  108 . “Wales” as used in this Detailed Description refers to the columns of loops that may extend along multiple courses. Wales extend perpendicular to the knitting direction. “Courses” refers to rows of loops formed from a yarn that extend along the knitting direction. In other words, a floating portion  148  may extend over multiple needles of a knitting machine which may or may not be holding loops. The distance that a floating portion  148  extends through the knitted component  108  may be referred to in terms of number of wales of the knitted component  108 . Multiple third yarns  124  may extend through adjacent courses (e.g., consecutive courses as shown in  FIGS.  4 - 6   ) or nonadjacent courses of the first knit courses  134 . In some embodiments, the floating portion  148  of the third yarn  124  (e.g., a high tenacity yarn) may extend along a first course  134   a  passing multiple wales or needles while not interacting with loops of the first course  134   a.  For example, as shown in  FIG.  4   , in section A, the floating portion  148  extends past ten wales, in section B, the floating portion  148  extends past 5 wales, and in section C, the floating portion  148  extends past 5 wales. 
     By varying the length of floating portion  148  (e.g., the number of wales the floating portion extends past), desired stretch resistance may be achieved. A floating portion  148  that extends past a greater number of wales provide greater stretch resistance than a floating portion  148  that extends a fewer number of wales (i.e., since floating yarns lack the inherent stretch in a knitted loop). For example, a floating portion  148  that extends past twenty-seven wales (e.g., as shown in  FIG.  5   ) may provide greater stretch resistance than a floating portion  148  that extends past 10 wales (e.g., as shown in  FIG.  4   ) due to the inherent stretchability of intervening knitted areas (e.g., as shown in  FIG.  4   , areas  202  and  204 ). Also, a floating portion  148  that extends past a greater number of wales may provide stretch resistance over a greater portion of the knitted component  108 . In some embodiments, as shown in  FIG.  4   , the floating portion  148  may extend over a portion of the knitted component  108  (e.g., extend partially over the lateral  110  and/or medial  112  side of the upper  102 ). In some embodiments, as shown in  FIG.  5   , the floating portion  148  may extend from the biteline  106  to the throat area  114  (and thus provide stretch resistance along a length of the floating portion  148  between the biteline  106  and the throat area  114 ). Thus, the length of the floating portions  148  may be adjusted for a particular stretch-resistant property in a particular area within an article of footwear  100 . 
     As discussed above, in some embodiments, the third yarn  124  may include at least one interlooped portion  150  (e.g., defining the knitted areas  202  and  204 ) that interloops with loops of an adjacent course of the first knit courses  134 . For example, as shown in  FIG.  4   , in sections D, and E, the third yarn  124  includes two interlooped portions  150 . Each interlooped portion  150  includes three loops that respectively interloop with three loops of a second course  134   b  (e.g., adjacent to and intermeshed with the first course  134   a  of the first knit courses  134 ). In this embodiment, in sections D and E, the loops of the interlooped portion  150  and the loops of the second course  134   b  collectively form a course of the first knit courses  134 , and the loops of the interlooped portion  150  are exposed on the exterior surface  152  of the upper  102 . The interlooped portions  150  (e.g., as shown in section F in  FIG.  4   ) may help secure the adjacent floating portions  148  (e.g., as shown in sections B and C in  FIG.  4   ) to the knitted component  108 . 
     Interlooped portions  150  may provide more stretchability than the floating portions  148  due to the loops formed in the interlooped portions  150 . Interlooped portions with a greater length may provide stretchability over a greater portion of the knitted component  108 . By selectively incorporating the floating portions  148  and the interlooped portions  150  at desired locations along a length of a third yarn  124 , various stretch resistance may be provided along the length of the third yarn  124 . For example, as shown in  FIG.  4   , the third yarn  124  includes floating portions in sections A, B, and C that are continuous with interlooped portions  150  in sections D and E. The length, number, and location of the floating portions  148  and the interlooped portions  150  may be varied, as desired and/or needed, to achieve desired stretch resistance along the length of the third yarn  124  without departing from the scope of the present disclosure. Additionally, it is contemplated that the loops of the third yarn  124  may provide desirable aesthetics, particularly where the third yarn  124  is a different color (or has another varying visual characteristic) relative to the adjacent yarns in the knitted component. 
     In some embodiments, the third yarn  124  may include at least one exposed portion  156  that does not interloop with adjacent first knit courses  134  but extend over the exterior surface  152  of the upper  102 . For example, as shown in  FIG.  5   , the third yarn  124  includes four exposed portions  156  that are spaced along the length of the third yarn  124 . Each exposed portion  156  includes two ends that extend from the exterior surface  152  to the interior surface  154  of the upper  102  through respective loops of the first course  134   a  of the first knit courses  134 . The length of each exposed portion  156  may be varied by selectively extending the two ends of the exposed portion  156  through respective loops of a course of the first knit courses  134  that are spaced apart a desired distance. To prevent the exposed portions  156  from being snagged or caught on an external item, the exposed portions  156  are configured to at least partially contact the exterior surface  152  without visible gap therebetween. The exposed portions  156  provide a degree of stretch resistance between the floating portions  148  and the interlooped portions  150 . 
     Various combinations of the floating portions  148 , interlooped portions  150 , and exposed portions  156  may be selectively incorporated into the knitted component  108  to achieve desired properties of stretch resistance in particular locations of an upper  102 . Floating portions  148  may be utilized to enhance the strength of desired areas of the upper  102  and counteract the elevated forces that these areas of the upper  102  may experience during use of the article of footwear  100 . In addition, by utilizing the floating portions  148  at desired areas of the upper  102 , a wear&#39;s foot may be comfortably restricted from movement within the article of footwear  100 , securing the foot in relation to the sole structure  104 . This is advantageous for allowing the upper  102  to be formed primarily from very elastic materials (e.g., recyclable materials) with desired strength provided in particular locations as needed, and thus costs may be reduced. For example, as shown in  FIG.  5   , the floating portions  148  extend in the general direction from the biteline  106  to the throat area  114  in the midfoot area of the upper  102 , which provide desired strength in these locations and help secure the foot in the article of footwear  100  (e.g., in the midfoot area  116 , especially when the first knit courses  134  are formed from very elastic materials, such as recyclable materials). 
     As discussed above, by varying the combination of the floating portions  148 , interlooped portions  150 , and exposed portions  156 , the third yarn  124  may impart different stretch resistance in different regions along a length of a course of the first knit courses  134 . This is advantageous for allowing additional strength (provided by the floating portions  148 ) to be selectively provided at spaced apart locations and even any locations, as desired and/or needed, during a continuous knitting process, without the need for significant post-knitting processes or steps. 
     The knitted component  108  with a desired combination of the floating portions  148 , interlooped portions  150 , and exposed portions  156  may be used to counteract typical forces that may be exerted throughout the upper  102  during use. Typical forces are forces that may occur in an article of footwear  100  that is used for a particular purpose, for example, an article of footwear  100  configured for a sport or other athletic activity. The typical motions for a player or participant of a sport or athletic activity cause force to be exerted on an upper  102  of the article of footwear  100  in certain areas. Typical forces may be forces that extend through an article of footwear  100  as a foot presses against the upper  102 . The foot may stretch or deform the upper  102  as the foot extends into the upper  102 . By placing large floating portions  148  in particular locations in the knitted component  108  incorporated into the upper  102 , the floating portions  148  may be used to counteract the forces from a foot and assist with securing the foot within the article of footwear  100  and resist deformation of the upper  102 . 
     Additionally, the floating portions may direct or distribute forces such that the stretch of the upper  102  may be limited in areas incorporating this structure. As depicted, the area of the upper  102  as shown in  FIG.  5    may form a less elastic structure than the areas of the upper  102  as shown in  FIGS.  4  and  6   . The foot may press against the interior surface  154 , and the area shown in  FIG.  5    may better hold its shape than the areas shown in  FIGS.  4  and  6    when subjected to a similar force. The floating portions  148  may limit the stretch of the upper  102  and create channels or paths for the force to run along. The floating portions  148  therefore may accept or direct the forces, thereby reducing the amount of force that may act upon other courses of the knitted component  108  of the upper  102 . For example, as shown in  FIG.  5   , the force exerted to the lateral side  115  and/or the medial side  117  of the throat area  114  by a wearer&#39;s foot may be distributed by the floating portions  148  along the length of the floating portions  148  to the biteline  106 . Thus, the use of floating portions  148  may allow for better stability and control in corresponding areas of the upper  102 , increase performance and durability, as well as increase a user&#39;s comfort and feel. 
     The third yarn  124  may extend into the throat area in various ways (e.g., as shown in  FIGS.  4 - 6   ). Any of the various ways of extending the third yarn  124  inside the pocket  139  and any combination thereof may be selectively included in the knitted component  108 . In some embodiments, as shown in  FIG.  4   , the third yarn  124  extends through a first course  134   a  of the first knit courses  134  from the biteline  106  to the edge  158  between the first area  132  and the second area  126 , extends over the edge  158  into the pocket  139  in the second area  126  for a predetermined length (e.g., a very short distance without interlooping with any of the second knit courses  128  in the second area  126 ), and then extends back into the first area  132  through another course of the first knit courses  134  (e.g., a second course  134   b,  which may or may not adjacent to the first course  134   a ) to the biteline  106 . 
     In some embodiments, as shown in  FIG.  5   , the third yarn  124  extends around a first opening  130   a  and back into the first area  132 . More than one course of the third yarn  124  may extend around the same first opening  138   a  in the second area  126 . For example, as shown in  FIG.  5   , four of the third yarns  124  have this feature. The portions of the third yarn  124  that are in the second area  126  may remain unexposed from an outer surface of the upper  102 , particularly when the second area  126  includes a tubular knit construction with an outer knit layer and an inner knit layer, as discussed above. For example, the depicted portions  210  of the third yarn  124  may remain within the pocket of the tubular area of knitting. Advantageously, this may prevent the portions  210  of the third yarn  124  from snagging or otherwise interfering with an elements beyond the exterior surface of the upper. 
     As shown, the portions  210  may at least partially wrap around at least one opening  130   a  (and/or other openings). This may be particularly advantageous where the opening  130   a  is configured to receive a shoelace or other fastening element for an article of footwear, as the forces exerted on the opening  130   a  may be transferred through the third yarn  124  to a different area of the article of footwear (e.g., the sole structure). 
     In some embodiments, as shown in  FIG.  6   , the third yarn may extend into the second area  126 , and may form loops  208  in the second area  126  (perhaps in combination with another yarn, such as the second yarn  122  discussed above). Such an embodiment may be advantageous for its simplicity of manufacturing on a conventional kitting machine, and it may provide a superior (e.g., very strong and durable) connection between the first area  132  and the second area  126  since the third yarns  124  form loops in both areas (e.g. with continuous segments of yarn between said loops). 
     The subject-matter of the disclosure may also relate, among others, to the following aspects: 
     A 1st aspect relates to an upper for an article of footwear. The upper may include a first area located on at least one of a lateral and a medial side of the upper, where the first area comprises a plurality of first knit courses, and where at least a majority of the first knit courses are at least partially formed by a first yarn. The upper may further include a second area located adjacent to the first area of the upper, where the second area extends through at least one of a lateral side and a medial side of a throat area of the upper, where the second area comprises a plurality of second knit courses, and where at least a majority of the second knit courses are formed by a second yarn. The second yarn may have a tenacity of at least 5 g/D. 
     A 2nd aspect relates to the preceding aspect, where a third yarn extends from a biteline of the upper to the second area, and where the third yarn includes at least one floating portion extending through at least one of the first knit courses in the first area. 
     A 3rd aspect relates to the aspect 2, where the third yarn includes a polyester material. 
     A 4th aspect relates to aspect 2 or 3, where the third yarn has a tenacity of at least 5 g/D. 
     A 5th aspect relates to any of the preceding aspects, where the first yarn consists of a polyethylene terephthalate (PET) material. 
     A 6th aspect relates to the any of the preceding aspects, where the second area comprises a two-layer construction formed by the second knit courses, and where a pocket is located between a first layer and a second layer. 
     A 7th aspect relates to the aspect 6, where a first opening and a second opening located in the first layer of the second area, and where the first opening and the second opening are configured to receive a fastening element. 
     An 8th aspect relates to any of the preceding aspects, where a third yarn is included that forms at least one loop within a first knit course of the plurality of first knit courses, and where the second area includes a first layer and a second layer, where a pocket is located between the first layer and the second layer, and where the third yarn extends inside the pocket. 
     A 9th aspect relates to aspect 8, where the at least one loop is exposed on an exterior surface of the upper. 
     A 10th aspect relates to any of the preceding aspects, where the second yarn is substantially excluded from the first area. 
     An 11th aspect relates to an upper for an article of footwear, comprising: a first area located on at least one of a lateral and a medial side of the upper, where the first area comprises a plurality of first knit courses, and where at least a majority of the first knit courses are at least partially formed by a first yarn; and a second area located adjacent to the first area of the upper, where the second area extends through at least one of a lateral side and a medial side of a throat area of the upper, where the second area comprises a plurality of second knit courses, and where at least a majority of the second knit courses are formed by a second yarn, where the second yarn has a tenacity of at least 5 g/D, and where the first yarn has a tenacity of less than 5 g/D. 
     A 12th aspect relates to aspect 11, where the second yarn includes a polyethylene terephthalate (PET) material. 
     A 13th aspect relates to any of aspects 11-12, where the second area comprises a two-layer construction formed by the second knit courses, and where a pocket is located between a first layer and a second layer. 
     A 14th aspect relates to aspect 13, where a first opening and a second opening are located in the first layer of the second area, and where the first opening and the second opening are configured to receive a fastening element. 
     A 15th aspect relates to any of aspects 11-14, where a third yarn extends from a biteline of the upper to the second area, and where the third yarn includes at least one floating portion extending through at least one of the first knit courses in the first area. 
     A 16th aspect relates to aspect 15, where the second area includes a first layer and a second layer, where a pocket is located between the first layer and the second layer, and where the third yarn extends inside the pocket. 
     A 17th aspect relates to any of aspects 15-16, where the third yarn includes a polyester material. 
     An 18th aspect relates to any of aspects 15-17, where the third yarn has a tenacity of at least 5 g/D. 
     A 19th aspect relates to an upper for an article of footwear, comprising: a first area located on at least one of a lateral and a medial side of the upper, where the first area comprises a plurality of first knit courses, and where at least a majority of the first knit courses are at least partially formed by a first yarn, and where the first area include a single-layer construction; and a second area located adjacent to the first area of the upper, where the second area extends through at least one of a lateral side and a medial side of a throat area of the upper, where the second area comprises a plurality of second knit courses, and where at least a majority of the second knit courses are formed by a second yarn, where the second area comprises a two-layer construction formed by the second knit courses, and where a pocket is located between a first layer and a second layer. 
     A 20th aspect relates to aspect 19, where a first opening and a second opening located in the first layer of the second area, and where the first opening and the second opening are configured to receive a fastening element. 
     While various embodiments of the present disclosure have been described, the present disclosure is not to be restricted except in light of the attached claims and their equivalents. One skilled in the relevant art will recognize that numerous variations and modifications may be made to the embodiments described above without departing from the scope of the present invention, as defined by the appended claims. Moreover, the advantages described herein are not necessarily the only advantages of the present disclosure and it is not necessarily expected that every embodiment of the present disclosure will achieve all of the advantages described.