Patent Publication Number: US-11659878-B2

Title: Apparel layer system

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application, entitled “Apparel Layer System,” is a continuation application of U.S. application Ser. No. 16/117,724, filed Aug. 30, 2018, granted as U.S. Pat. No. 10,786,023, and entitled “Apparel Layer System,” which claims the benefit of priority of U.S. Prov. App. No. 62/557,806, entitled “Apparel Layer System,” and filed Sep. 13, 2017. The entireties of the aforementioned applications are incorporated by reference herein. 
    
    
     TECHNICAL FIELD 
     Aspects herein relate to an apparel layer system. More specifically, aspects herein relate to an apparel layer system configured to provide adjustable insulation, warming, and/or permeability. 
     BACKGROUND 
     Typical apparel items or garments are structured to provide a fixed level of insulation, warming, and/or a fixed level of air permeability. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Examples of the present invention are described in detail below with reference to the attached drawing figures, wherein: 
         FIG.  1 A  illustrates a side view of an example apparel layer system in a first state in accordance with aspects herein; 
         FIG.  1 B  illustrates a side view of the example layer system of  FIG.  1 A  in a second state in accordance with aspects herein; 
         FIG.  1 C  illustrates a side view of the example layer system of  FIG.  1 A  in a third state in accordance with aspects herein; 
         FIG.  2    illustrates an exploded view of an example apparel layer system in accordance with aspects herein; 
         FIG.  3    illustrates an exploded view of another example apparel layer system in accordance with aspects herein; 
         FIG.  4    illustrates a top view of the example apparel layer system of  FIG.  3    in an as-assembled arrangement and in a first state in accordance with aspects herein; 
         FIG.  5    illustrates a top view of the example apparel layer system of  FIG.  3    in an as-assembled arrangement and in a second state in accordance with aspects herein; 
         FIG.  6    illustrates an exploded view of an alternative configuration for an example apparel layer system in accordance with aspects herein; 
         FIG.  7 A  illustrates a side view of the example apparel layer system of  FIG.  6    in a first state in accordance with aspects herein; 
         FIG.  7 B  illustrates a side view of the example apparel layer system of  FIG.  6    in a second state in accordance with aspects herein; 
         FIGS.  8 A- 8 C  illustrate an example adjustment mechanism for use with an apparel layer system in accordance with aspects herein; 
         FIGS.  9 A- 9 B  illustrate another example adjustment mechanism for use with an apparel layer system in accordance with aspects herein; 
         FIG.  10    illustrates an upper-body garment incorporating an example apparel layer system in accordance with aspects herein; 
         FIG.  11    illustrates a lower-body garment incorporating an example layer system in accordance with aspects herein; 
         FIG.  12    illustrates an example construction method of forming an apparel layer system in accordance with aspects herein; 
         FIG.  13    illustrates a flow diagram of an example method of forming an apparel layer system in accordance with aspects herein; and 
         FIGS.  14 A- 14 B  illustrate an example adjustment mechanism for use with an apparel layer system in accordance with aspects herein. 
     
    
    
     DETAILED DESCRIPTION 
     The subject matter of the present invention is described with specificity herein to meet statutory requirements. However, the description itself is not intended to limit the scope of this disclosure. Rather, the inventors have contemplated that the claimed or disclosed subject matter might also be embodied in other ways, to include different steps or combinations of steps similar to the ones described in this document, in conjunction with other present or future technologies. Moreover, although the terms “step” and/or “block” might be used herein to connote different elements of methods employed, the terms should not be interpreted as implying any particular order among or between various steps herein disclosed unless and except when the order of individual steps is explicitly stated. 
     At a high level, aspects herein are directed to an apparel layer system that can be used to provide variable and adjustable levels of insulation, warming, or air permeability. In example aspects, the apparel layer system may be integrated into a garment such as a top or a bottom or an apparel item such as a hat, sock, or the like. In one instance, the apparel layer system may be in the form of a panel piece or trim piece that is integrated into the garment or apparel item by affixing the trim piece to one or more garment portions or apparel item portions. In another instance, the apparel layer system may be integrally created through modifying the knitting, weaving, or construction process used to form the garment or apparel item. 
     In general, the apparel layer system comprises a first layer of material, a second layer of material, and a third layer of material. At least the first layer of material and the second layer of material extend in a first planar direction. The third layer of material is interposed between the first layer of material and the second layer of material such that a first surface of the third layer is positioned adjacent to a first surface of the first layer of material and is selectively affixed thereto. And a second opposite surface of the third layer of material is positioned adjacent to a first surface of the second layer of material and is selectively affixed thereto. An adjustment mechanism is coupled to the second layer of material. 
     Continuing, in example aspects, the adjustment mechanism can be mechanically manipulated between a plurality of positions which, in turn causes the second layer to be mechanically shifted or transitioned between different positions or states. In another example, the adjustment mechanism may automatically transition between the plurality of positions upon exposure to a stimulus such as, for example, moisture. When the adjustment mechanism is in a first position, the second layer is offset from the first layer in the first planar direction by a first amount, and the second layer is offset from the first layer in a second direction perpendicular to the first planar direction by a first amount. When the adjustment mechanism is in a second position, the second layer is offset from the first layer in the first planar direction by a second amount that is less than the first amount. As well, when the adjustment mechanism is in the second position, the second layer is offset from the first layer in the second direction perpendicular to the first planar direction by a second amount that is greater than the first amount. 
     The changes in offset (both in the first direction and the second direction) of the first and second layers are possible due to the selective attachment of the third layer of material to the first and second layers. In one example aspect, the third layer may be manipulated to form a series of folds with the long axis of the folds being in parallel with each other and perpendicular to a tension force exerted by the adjustment mechanism when mechanically manipulated. The apex regions of the folds are selectively attached to the surfaces of the first and second layers. As used throughout this disclosure, the term “apex region” may be generally defined as the region at which a material folds or bend over on itself so that one portion of the material covers (or is configured to cover) another portion of the material. The apex region may comprise a distinct bend or fold (i.e., a distinct point or apex) or may comprise a more general region (i.e., a more gradual fold). Continuing, when the adjustment mechanism is in, for instance, the first position, the folds extend generally in the first planar direction (i.e., they lie flat). However, when the adjustment mechanism is in the second position, the movement of the second layer causes the folds to extend generally in a direction that is non-planar to the first planar direction (i.e., they stand upright or partially upright). This causes a greater amount of vertical offset (i.e., offset in the z-direction) between the first and second layers of material. 
     The general construction described above may be used to provide variable levels of air permeability, warming, or insulation depending on the types of materials used to form the different layers. For instance, in example aspects, when the apparel layer system is configured to provide variable insulation, the different layers may be formed from a material that limits air movement through the material (e.g., a tightly woven material). When a relatively low level of insulation is desired, the adjustment mechanism may be maintained in the first position causing a small amount of vertical offset between the first and second layers. However, when a relatively greater level of insulation is needed (i.e., a level of insulation greater than when the adjustment mechanism is in the first position), the adjustment mechanism may be moved to the second position such that the vertical offset between the first and second layers is increased. This, in turn, creates an air pocket between the layers that can be used to trap and store heated air thus helping to insulate the wearer. 
     When the apparel layer system is configured to provide variable air permeability, at least the first and second layers of material may comprise perforations or apertures in select locations. When a relatively low level of air permeability is desired, such as when a wearer is at rest, the adjustment mechanism may be maintained in the first position. The placement of the apertures on the first and second layers of material is such that the apertures of the first layer are offset from (i.e., not aligned with) the apertures in the second layer when the adjustment mechanism is in the first position. This limits the flow of air through the layers. However, when a relatively greater amount of air permeability is desired, such as when the wearer is exercising, the adjustment mechanism may be moved to the second position. When the adjustment mechanism is in the second position, the apertures in the first layer align, or at least partially align, with the apertures in the second layer to facilitate the flow of air through the different layers. To further facilitate air flow between the layers, the third layer may be formed of a mesh material or from a material having apertures. 
     In example aspects, the apparel layer system may be configured to provide variable levels of warming. In this aspect, the third layer of material may comprise a reflective material or a material having a reflective deposit on at least the first surface of the third layer of material (i.e., the surface that faces toward the first layer of material). When a relatively moderate level of radiant warming is desired, the adjustment mechanism may be maintained in the first position. In this position, the reflective surface of the third layer of material is generally planar or extends in the first planar direction such that it is parallel or generally parallel to a wearer&#39;s body surface when the apparel layer system is incorporated into a garment or an apparel item. Thus, any radiant heat energy generated by the wearer may be reflected back toward the body surface of the wearer via the reflective surface. When warming is no longer necessary, the adjustment mechanism may be transitioned to the second position such that the reflective surface of the third layer of material is no longer planar with respect to the wearer&#39;s body surface. A result of this is that less heat is reflected back to the wearer and warming is reduced. 
     The variable warming feature may be combined with the variable permeability feature discussed above by including apertures in the first layer of material and the second layer of material. Thus, when radiant warming and limited air permeability is desired, the adjustment mechanism may be maintained in the first position, which causes the apertures in the first and second layers of material to be offset from each other limiting air movement through the apparel layer system. However, as described, when the third layer of material comprises a reflective surface, maintaining the adjustment mechanism in the first position causes the reflective surface to be relatively planar with respect to the wearer&#39;s body surface thereby promoting reflection of radiant heat produced by the wearer back to the wearer&#39;s body surface. When increased air permeability and decreased warming is desired, the adjustment mechanism may be transitioned to the second position causing the apertures in the first and second layer to align, or partially align, and further causing the reflective surface of the third layer of material to no longer be planar with respect to the wearer&#39;s body surface. The result is that air permeability through the aligned apertures is increased, and radiant energy produced by the wearer is no longer reflected back to the wearer&#39;s body surface. 
     The provision of variable levels of insulation, warming, and air permeability may also be facilitated by the use of an adjustment mechanism that is configured to be incrementally adjusted. For instance, in one example aspect, the adjustment mechanism may comprise a first magnetic strip having alternating and repeating magnetic elements (i.e., alternating and repeating North and South poles) that is coupled to the second layer of the apparel layer system. A complementary second magnetic strip, also having alternating and repeating magnetic elements, may be applied to the garment such that it is positioned to be in contact with the first magnetic strip. The movement of the first magnetic strip may be initiated by a mechanical pulling force (e.g., a wearer&#39;s fingers) having sufficient magnitude to overcome the attraction force between the magnetic elements located on the different strips. Once movement is initiated, the movement of the first magnetic strip is constrained by the second magnetic strip such that the two strips are maintained in an abutting relationship and slidably move relative to one another in discrete steps guided by the alternating and repeating magnetic elements of the strips. The use of this configuration enables the second layer of the apparel layer system to be shifted in incremental steps in relation to the first layer of the apparel layer system. In turn, the amount of vertical offset between the first and second layers when the apparel layer system is used for insulation, or the amount of alignment between the apertures of the first and second layers when the apparel layer system is used for permeability, or the amount of reflective surface exposed to the wearer&#39;s body surface can be incrementally controlled to provide fine-tuning of insulation levels, permeability levels, and warming levels respectively. 
     Accordingly, aspects herein are directed to an apparel layer system comprising a first layer extending in a first planar direction, a second layer extending in the first planar direction, and a third layer positioned between the first layer and the second layer. The third layer has a first surface and a second surface opposite the first surface, where the first surface is positioned adjacent the first layer and the second surface is positioned adjacent the second layer. Further, the first surface of the third layer is selectively affixed to the first layer and the second surface is selectively affixed to the second layer. The apparel layer system further comprises an adjustment mechanism coupled to the second layer, where when the adjustment mechanism is in a first position, the second layer is offset from the first layer by a first amount, and when the adjustment mechanism is in a second position, the second layer is offset from the first layer by a second amount. 
     In another aspect, an apparel layer system is provided comprising a first layer having a first aperture, where the first layer extends in a first planar direction. The apparel layer system further comprises a second layer having a second aperture, where the second layer extends in the first planar direction. Additionally, the system comprises a third layer positioned between the first layer and the second layer, where the third layer has a first surface and a second surface opposite the first surface. The first surface is positioned adjacent the first layer and the second surface is positioned adjacent the second layer; the first surface is selectively affixed to the first layer and the second surface is selectively affixed to the second layer. The apparel layer system also comprises an adjustment mechanism coupled to the second layer. When the adjustment mechanism is in a first position the first aperture is offset from the second aperture, and when the adjustment mechanism is in a second position, the first aperture is aligned with the second aperture. 
     Aspects herein are also directed to a method of manufacturing an apparel layer system. The method comprises providing a first layer of material, providing a second layer of material, and providing a third layer of material, where the third layer of material has a first surface and a second surface opposite the first surface. The third layer of material is manipulated to form a set of folds. The first surface of the third layer of material is selectively attached to a first surface of the first layer of material, and the second surface of the third layer of material is selectively attached to a first surface of the second layer of material. The method also comprises coupling an adjustment mechanism to the second layer of material. When the adjustment mechanism is in a first position, the set of folds are in a generally planar relationship with the first layer of material and the second layer of material, and when the adjustment mechanism is in a second position, the set of folds are in a generally non-planar relationship with the first layer of material and the second layer of material. 
     As used throughout this disclosure, positional terms such as “anterior,” “posterior,” “front,” “back,” “side,” “lateral,” “medial,” “inner-facing surface,” “outer-facing surface,” and the like are to be given their common meaning with respect to the apparel layer system as incorporated in a garment or apparel item being worn as intended by a hypothetical wearer standing in an upright position (i.e., standing in anatomical position) and as shown and described herein. Still further, the phrase “configured to contact,” “adapted to contact,” or other similar phrases used when describing different portions of the apparel layer system and/or the garment and/or the apparel item in relation to a wearer refer to an apparel layer system and/or a garment and/or apparel item that is appropriately sized for the particular wearer. Terms such as “affixed,” “secured,” “coupled,” and the like may mean releasably securing two or more elements together using affixing technologies such as zippers, hook-and-loop fasteners, releasable adhesives, buttons, snaps, and the like. These terms may also mean permanently affixing two or more elements together using technologies such as stitching, bonding, welding, gluing, and the like. 
     Turning now to  FIG.  1 A , a side view of an example layer system  100  in a first state is provided in accordance with aspects herein. The apparel layer system  100 , in example aspects, may comprise a first layer of material  110 , a second layer of material  112 , and a third layer of material  114  interposed or positioned between the first layer of material  110  and the second layer of material  112 . The first layer of material  110  may comprise a first surface  111  and a second surface  113  opposite the first surface  111 , and the second layer of material  112  may comprise a first surface  115  and a second surface  117  opposite the first surface  115 . Similarly, the third layer of material  114  may comprise a first surface  119  and a second surface  121  opposite the first surface  119 . 
     Continuing, when the third layer of material  114  is interposed or positioned between the first and second layers of material  110 / 112 , the first surface  119  of the third layer of material  114  may be positioned generally adjacent to the first surface  111  of the first layer of material  110  and selectively affixed thereto. Further, the second surface  121  of the third layer of material  114  may be positioned generally adjacent to the first surface  115  of the second layer of material  112  and selectively affixed thereto. In one example aspect, the third layer of material  114  comprises a series of folds  118  (seen from the side in  FIG.  1 A ). Each fold  118  may comprise a first apex region  120  and an opposite second apex region  122 . To selectively affix the first surface  119  of the third layer of material  114  to the first surface  111  of the first layer of material  110 , the first apex region  120  of the folds  118  may be affixed to the first surface  111  of the first layer of material  110  using, for example, stitching, bonding, spot welding, an adhesive, and the like. To selectively affix the second surface  121  of the third layer of material  114  to the first surface  115  of the second layer of material  112 , the second apex region  122  may be affixed to the first surface  115  of the second layer of material  112  using, for example, stitching, bonding, spot welding, an adhesive, and the like. In this example, the remaining portions of the third layer of material  114  remain unaffixed from the first and second layers of material  110 / 112 . To describe it a different way, except for the first and second apex regions  120 / 122 , the folds  118  remain generally unaffixed from or unattached to the first and second layers of material  110 / 112 . 
     In example aspects, the first layer of material  110  extends in a first planar direction with reference to Cartesian coordinate system  101 . To describe it a different way, the first layer of material  110  extends in the direction of its surface plane, where the surface plane of the first layer of material  110  can be described as a two-dimensional plane having an x direction and a y direction. As well, the second layer of material  112  also extends in the first planar direction. In other words, the second layer of material  110  extends in the direction of its surface plane, where the surface plane of the second layer of material  112  can also be described as a two-dimensional plane having an x direction and a y direction. As such, the surface plane of the second layer of material  112  is generally parallel to and offset from the surface plane of first layer of material  110 . 
     When the apparel layer system  100  is in a first state, the folds  118  of the third layer of material  114  are folded (i.e., the portions of the folds  118  between their respective apex regions  120  and  122  generally abut, or touch each other, or are positioned adjacent to one another such that the folds  118  generally lie flat). For clarity, the folds  118  in  FIG.  1 A  are not shown touching each other. When folded, the folds  118  of the third layer of material  114  also generally extend in the first planar direction and an angle, e, formed between, for instance, a fold  118  and the second layer of material  112  (or first layer of material  110 ) may be less than, for example, 10 degrees. To describe it further, with respect to a particular fold  129 , the second apex region  122  of the fold  129  may be described as extending in the positive x-direction, and the first apex region  120  of the fold  129  may be described as extending in the negative x-direction with respect to the Cartesian coordinate system  101 . 
     In the first state as shown in  FIG.  1 A , the second layer of material  112  is offset from the first layer of material  110  in the first planar direction by a first amount  124 . More particularly, consider the fold  129 , where the second apex region  122  is positioned in a positive x-direction with respect to the first apex region  120  of the fold  129 . With this as context, the second apex region  122  of the fold  129  is offset from the first apex region  120  in the first planar direction by the first amount  124 . And because the first and second apex regions  120 / 122  are fixedly attached to the first and second layers of material  110 / 112  respectively, this also means that the second layer of material  112  is offset from the first layer of material  110  in the first planar direction by the first amount  124 . Further, in the first state, the second layer of material  112  is offset by a first amount  126  from the first layer of material  110  in a second direction perpendicular to the first planar direction. To describe it a different way with respect to the Cartesian coordinate system  101 , the second layer of material  112  is offset from the first layer of material  110  in the positive z-direction by the first amount  126 . 
     Additionally, the apparel layer system  100  may comprise an adjustment mechanism  116  coupled to the second layer of material  112 . As will be explained in greater depth below, the adjustment mechanism  116  may be used to shift the second layer of material  112  relative to the first layer of material  110  via the third layer of material  114 . 
       FIG.  1 B  illustrates the apparel layer system  100  in a second state in accordance with aspects herein. The second state may be achieved by exerting a tension force  127  on the adjustment mechanism  116  in a direction opposite to the direction in which the second apex regions  122  extend. With respect to  FIG.  1 A , for example, the tension force  127  may be exerted in the negative x-direction while the second apex regions  122  extend in the positive x-direction. Depending on the orientation of the apparel layer system  100  though, the directions may differ. For example, the tension force  127  may be in the positive x-direction while the second apex regions  122  extend in the negative x-direction. Or the tension force  127  may be in the positive y-direction while the second apex regions  122  extend in the negative y-direction. Or, in another example, the tension force  127  may be in the negative y-direction while the second apex regions  122  extend in the positive y-direction. Any and all aspects, and any variation thereof, are contemplated as being within the scope herein. 
     Continuing, due to the selective attachment of the third layer of material  114  to the second layer of material  112  via the second apex regions  122  and due to the selective attachment of the third layer of material  114  to the first layer of material  110  via the first apex regions  120 , movement of the second layer of material  112  using the adjustment mechanism  116  also causes the second apex regions  122  to move in the negative x-direction while the first apex regions  120  remain stationary (i.e., the first apex regions  120  act as anchor points). Moreover, due to just the second apex regions  122  of the folds  118  being selectively attached to the second layer of material  112 , and due to the second apex regions  122  extending in the positive x-direction, movement of the second layer of material  112  in the negative x-direction causes the folds  118  to begin to assume a more upright (or “unfolded”) configuration as shown in  FIG.  1 B . To describe it a different way, movement of the second layer of material  112  in the negative x-direction exerts a force on at least the second apex regions  122  of the folds  118  causing the second apex regions  122  to also move in the negative x-direction thereby causing the folds  118  to assume a more upright configuration. To describe it yet a different way, in the second state, the angle, e, between a fold  118  and the second layer of material  112  may be greater than the angle, e, when the apparel layer system  100  is in the first state. For example, the angle, e, in the second state may be greater than 10 degrees but less than, for example, 15 to 55 degrees. 
     In the second state as shown in  FIG.  1 B , the second layer of material  112  is offset from the first layer of material  110  in the first planar direction by a second amount  128 . More particularly, the second apex region of the fold  129  is offset from the first apex region  120  of the fold  129  in the first planar direction by the second amount  128 . In example aspects, the second amount  128  is less than the first amount  124 . In other words, there is less lateral offset in the first planar direction with respect to the apex regions  120 / 122  when the apparel layer system  100  is in the second state. And because the first and second apex regions  120 / 122  are fixedly attached to the first and second layers of material  110 / 112  respectively, this also means that there is less lateral offset in the first planar direction between the second layer of material  112  and the first layer of material  110 . Further, in the second state, the second layer of material  112  is offset by a second amount  130  from the first layer of material  110  in the second direction that is perpendicular to the first planar direction (i.e., offset in the positive z-direction). In example aspects, the second amount  130  is greater than the first amount  126 . In other words, there is greater vertical offset in the second direction when the apparel layer system  100  is in the second state as shown in  FIG.  1 B . 
       FIG.  1 C  illustrates the apparel layer system  100  in a third state in accordance with aspects herein. The third state may be achieved by continuing to exert the tension force  127  on the adjustment mechanism  116 . Continued movement of the second layer of material  112  via the adjustment mechanism  116  in the negative x-direction also causes continued movement of the second apex regions  122  of the third layer of material  114  in the negative x-direction. This movement in the negative x-direction causes the folds  118  to assume a generally upright (or “unfolded”) configuration as shown in  FIG.  1 C . To describe it a different way, in the third state, the angle, e, between a fold  118  and the second layer of material  112  may be greater than the angle, e, when the apparel layer system  100  is in the second state. For example, the angle, e, in the third state may be greater than 55 degrees. The degree measurements provided herein are example only and are used merely to illustrate that the angle, e, between a fold  118  and the second layer of material  112  (or the first layer of material  110 ) gradually increases as the folds  118  are transitioned to an upright position. 
     In the third state as shown in  FIG.  1 C , the second layer of material  112  is offset from the first layer of material  110  in the first planar direction by a third amount  132 . More particularly, the second apex region  122  of the fold  129  is offset from the first apex region  120  of the fold  129  in the first planar direction by the third amount  132 . In example aspects, the third amount  132  is less than the second amount  128 . In other words, there is even less lateral offset in the first planar direction between the two layers of material  110 / 112  with respect to the apex regions  120 / 122  when the apparel layer system  100  is in the third state. 
     Further, in the third state, the first layer of material  112  is offset by a third amount  134  from the first layer of material  110  in the second direction that is perpendicular to the first planar direction (the positive z-direction). In example aspects, the third amount  134  is greater than the second amount  130 . In other words, there is an even greater vertical offset in the second direction when the apparel layer system  100  is in the third state as shown in  FIG.  1 C . To summarize, as the apparel layer system  100  transitions from the first state to the third state, the amount of offset in the first planar direction between the first layer of material  110  and the second layer of material  112  with respect to, for instance, apex regions  120  and  122  of a particular fold  118  gradually decreases while the amount of offset between the first and second layers of material  110 / 112  in the second direction (the z-direction) gradually increases. 
     It is contemplated herein that there may be additional states of the apparel layer system  100  other than the states shown in  FIGS.  1 A- 1 C . For example, there may be states intermediate between the first state shown in  FIG.  1 A  and the second state shown in  FIG.  1 B . There also may be states intermediate between the second state shown in  FIG.  1 B  and the third state shown in  FIG.  1 C . It is also contemplated herein that the adjustment mechanism  116  may be configured to inhibit or stop movement in the negative x-direction once the folds  118  are in a substantially upright position (i.e., in the third state shown in  FIG.  1 C ). However, it is also contemplated herein that the adjustment mechanism  116  may be configured to continue movement in the negative x-direction thus causing the folds  118  to eventually lie flat again but have their second apex regions  122  extend in a negative x-direction and their first apex regions  120  extend in a positive x-direction. Any and all aspects, and any variation thereof, are contemplated as being within aspects herein. 
     Turning now to  FIG.  2   , an exploded view of an apparel layer system, such as the apparel layer system  100 , is provided in accordance with aspects herein and is referenced generally by the numeral  200 . The apparel layer system  200 , in example aspects, may be configured to provide variable levels of insulation and/or variable levels of warming. The apparel layer system  200  comprises a first layer of material  210  extending in a first planar direction, a second layer of material  212  extending in the first planar direction, and a third layer of material  214  positioned between or interposed between the first layer of material  210  and the second layer of material  212 . To help provide an insulation effect and to be suitable as an article of apparel, the first layer of material  210  and the third layer of material  214  may comprise, for example, a stretch woven or non-woven material (e.g., 2-way stretch or 4-way stretch) without engineered perforations or apertures. As used throughout this disclosure, the term “engineered” may be defined as formed in a post-material production step. To further help provide a radiant warming effect, at least a first surface  213  of the third layer of material  214  may optionally comprise a reflective deposit, where the first surface  213  is configured to be positioned adjacent to a surface of the first layer of material  210 . The reflective deposit may comprise an aluminum-based material, a copper-based material, another metal or metal alloy-based material, or non-metal materials such as metallic plastic, or other man-made materials. 
     Continuing, the second layer of material  212  may also comprise a woven or non-woven material (stretch or non-stretch) without engineered perforations or apertures, and may more particularly comprise a lightweight woven material. Use of woven material, especially tightly woven materials, and/or use of certain non-woven materials may help to limit movement of air through the different layers. Use of stretch woven or non-woven materials helps to contribute to wearer comfort and freedom-of-movement when the apparel layer system  200  is incorporated into a garment And use of lightweight woven materials may be suitable when the apparel layer system  200  is incorporated into a garment intended to be worn when exercising (e.g., running, and the like). The apparel layer system  200  further comprises an adjustment mechanism  216  coupled to the second layer of material  212 . 
     With respect to the third layer of material  214 , the third layer of material  214  comprises a series of folds  218  with each fold having a long axis  224 . The long axes  224  of the folds  218  are arranged in parallel to each other. Further, each fold  218  comprises a first apex region  220  and a second apex region  222 . In example aspects, the adjustment mechanism  216  is positioned on the second layer of material  212  such that it is configured to exert a tension force that is perpendicular to the long axes  224  of the folds  218 . As described above, the first apex regions  220  may be selectively affixed to the first layer of material  210 , and the second apex regions  222  of the folds  218  may be selectively affixed to the second layer of material  212 . 
     When the apparel layer system  200  is assembled, it assumes a structure similar to the apparel layer system  100  of  FIGS.  1 A- 1 C . As such, when the apparel layer system  200  is in a first state, such as the first state shown in  FIG.  1 A , the folds  218  extend generally in the first planar direction and, more specifically, the second apex regions  222  may extend in the positive x-direction, the first apex regions  220  may extend in the negative x-direction, and an angle, e, between a fold  218  and, for instance, the second layer of material  212  may be less than, for example, 10 degrees. Because the folds  218  generally lie flat in the first state, there is a small amount of vertical offset between the first and second layers of material  210 / 212 . Thus, configuring the apparel layer system  200  to be in the first state may be useful when a light amount of insulation is needed such as during exercise in cool conditions. 
     When the third layer of material  214  optionally comprises a reflective deposit on its first surface  213 , warming may be provided when the apparel layer system  200  is in the first state. For instance, in the first state, the folds  218  extend generally in the first planar direction (i.e., they lie flat) causing the reflective first surface  213  to be in a generally planar relationship with a body surface of a wearer when the apparel layer system  200  is incorporated into a garment or apparel item. Radiant heat energy produced by the wearer would be reflected back to the wearer&#39;s body surface via the reflective first surface  213  of the third layer of material  214  thereby helping to warm the wearer when at rest. 
     To cause the apparel layer system  200  to provide a higher level of insulation, the adjustment mechanism  216  may be tensioned in, for example, the negative x-direction thereby causing the second apex regions  222  to also move in the negative x-direction due to the selective attachment of the second apex regions  222  to the second layer of material  212 , while the first apex regions  220  generally remain stationary (e.g., they do not move in the negative x-direction or the positive x-direction). In example aspects, the movement of the adjustment mechanism  216  may cause the apparel layer system  200  to transition to the second state shown in  FIG.  1 B . As described, in the second state there is a greater amount of vertical offset (offset in the z-direction) between the first layer of material  210  and the second layer of material  212 . The greater amount of vertical offset between the layers  210 / 212  may help to trap warmed air between the layers  210 / 212  and provide a higher degree of insulation as compared to the first state. The higher amount of insulation may be useful when the wearer is exercising in colder conditions or is trying to maintain warmth before or after exercise. 
     A yet greater amount of insulation may be achieved by continuing to tension the adjustment mechanism  216  in the negative x-direction to cause the apparel layer system  200  to transition to a third state such as that shown in  FIG.  1 C . In the third state, there is yet a greater amount of vertical offset (offset in the z-direction) between the layers  210 / 212  allowing for a greater space for trapping warmed air. As mentioned earlier, it is contemplated herein that additional states between the first state and the third state may be achieved so that a customizable level of insulation may be provided. 
     When the third layer of material  214  optionally comprises a reflective deposit on its first surface  213 , radiant warming may be reduced when the apparel layer system  200  is in the second or third state to prevent overheating the wearer. For instance, in the second or third state, the folds  218  extend generally in the second direction generally perpendicular to the first planar direction causing the reflective first surface  213  to be in a generally perpendicular relationship with a body surface of a wearer when the apparel layer system  200  is incorporated into a garment or apparel item. Reflection of radiant heat energy produced by the wearer would thereby be reduced with a subsequent reduction in radiant warming. 
     Turning now to  FIG.  3   , an exploded view of an apparel layer system, such as the apparel layer system  100 , is provided in accordance with aspects herein and is referenced generally by the numeral  300 . The apparel layer system  300 , in example aspects, may be configured to provide variable levels of air permeability. The apparel layer system  300  comprises a first layer of material  310  extending in a first planar direction, a second layer of material  312  extending in the first planar direction, and a third layer of material  314  positioned between or interposed between the first layer of material  310  and the second layer of material  312 . To help provide air permeability, the first layer of material  310  may comprise, for example, a knit, woven, or non-woven material with a first set of perforations or apertures  316  formed at predetermined locations on the first layer of material  310 . And the second layer of material  212  may also comprise a knit, woven, or non-woven material with a second set of perforations or apertures  318  formed at predetermined locations on the second layer of material  312 . The apparel layer system  300  further comprises an adjustment mechanism  320  coupled to the second layer of material  312 . The first and second sets of apertures  316 / 318  may be engineered through a mechanical process such as die cutting, laser cutting, water jet cutting, and the like, or the first and second sets of apertures  316 / 318  may be formed by modifying the knitting or weaving process used to form the respective layers of material  310  and  312 . Any and all aspects, and any variation thereof, are contemplated as being within aspects herein. 
     With respect to the third layer of material  314 , in one example aspect the third layer of material  314  may comprise a mesh material (shown in  FIG.  3   ) to facilitate the flow of air through the different layers of material  310 ,  312 , and  314 . However, it is contemplated herein that the third layer of material  314  may comprise a different construction such as a knit material, a loosely woven material, or a material having engineered apertures. The third layer of material  314  comprises a series of folds  322  with each fold  322  having a long axis  324 . The long axes  324  of the folds  322  are arranged in parallel to each other. Further, each fold  322  comprises a first apex region  326  and a second apex region  328  opposite the first apex region  326 . In example aspects, the adjustment mechanism  320  is positioned on the second layer of material  312  such that it is configured to exert a tension force that is perpendicular to the long axes  324  of the folds  322 . As described above, the first apex regions  326  may be selectively affixed to the first layer of material  310 , and the second apex regions  328  of the folds  322  may be selectively affixed to the second layer of material  312 . 
     In an alternative aspect, and when the apparel layer system  300  is used to provide warming and permeability, the third layer of material  314  may comprise a material having a reflective deposit on at least its first surface  311 , where the first surface  311  is configured to be positioned adjacent to a first surface  305  of the first layer of material  310 . The reflective deposit may comprise an aluminum-based material, a copper-based material, another metal or metal alloy-based material, or non-metal materials such as metallic plastic, or other man-made materials. 
     When the apparel layer system  300  is assembled, it assumes a structure similar to the apparel layer system  100  of  FIGS.  1 A- 1 C . As such, when the apparel layer system  300  is in a first state, such as the first state shown in  FIG.  1 A , the folds  322  extend generally in the first planar direction and, more specifically, the second apex regions  328  may extend in the positive x-direction, the first apex regions  326  may extend in the negative x-direction, and an angle, e, between a fold  322  and, for instance, the second layer of material  312  may be less than, for example, 10 degrees. Because the folds  322  generally lie flat in the first state, there is a small amount of vertical offset (offset in the z-direction) between the first and second layers of material  310 / 312 . Further, because the folds  322  generally lie flat in the first state, a greater percentage of the surface area of the first surface  311  of the third layer of material  314  may be positioned adjacent to the first surface  305  of the first layer of material  310  as compared to when the apparel layer system is in the second state or third state. 
     The first and second set of apertures  316 / 318  may be positioned on the first and second layers of material  310 / 312  respectively such that when the apparel layer system  300  is in the first state, the first set of apertures  316  are not aligned with the second set of apertures  318  such that there is not a direct communication path between the first layer of material  310  and the second layer of material  312 . To describe it a different way, when the apparel layer system  300  is in the first state, the first set of apertures  316  are laterally offset from the second set of apertures  318  such that there is little to no overlap between the apertures  316 / 318  (e.g., less than, for instance, 10% overlap between the apertures  316 / 318 ). 
     This is depicted more clearly in  FIG.  4    which depicts a top view of the apparel layer system  300  when the apparel layer system  300  is in the first state. As shown, the second layer of material  312  is offset from the first layer of material  310  in the first planar direction by a first amount of offset  410 . Further, the apertures  318  of the second layer of material  312  are offset from the apertures  316  in the first layer of material  310  by the first amount  410  (as measured from the center of each aperture  316 / 318 ). 
     As shown in  FIG.  4   , the apertures  316  and the apertures  318  are not aligned with each other. To describe it a different way, the apertures  316  and  318  are offset from each other in at least the x-direction such that there is little if any overlap between the apertures  316  and  318  (e.g., less than, for example, 10% overlap). Thus, in the first state, there is generally not a direct communication path between the first layer of material  310  and the second layer of material  312  which helps to inhibit air flow through the two layers  310 / 312 . 
     When the third layer of material  314  optionally comprises a reflective deposit on its first surface  311 , radiant warming may be provided when the apparel layer system  300  is in the first state. For instance, in the first state, the folds  322  extend generally in the first planar direction (i.e., they lie flat) causing the reflective first surface  314  to be in a generally planar relationship with a body surface of a wearer when the apparel layer system  300  is incorporated into a garment or apparel item. Radiant heat energy produced by the wearer would be reflected back to the wearer&#39;s body surface via the reflective first surface  311  of the third layer of material  314  thereby helping to warm the wearer when at rest. 
     Returning generally to  FIG.  3   , to cause the apparel layer system  300  to provide a higher level of permeability, the adjustment mechanism  320  may be tensioned in, for example, the negative x-direction thereby causing the second apex regions  328  to also move in the negative x-direction due to the selective attachment of the second apex regions  328  to the second layer of material  312  while the first apex regions  326  generally remain stationary (e.g., they do not move in the negative x-direction or the positive x-direction). In example aspects, the movement of the adjustment mechanism  320  may cause the apparel layer system  300  to transition to the second state or the third state as shown in  FIG.  1 B  and  FIG.  1 C  respectively. As described, in the second state (or third state) the amount of offset in the first planar direction between the first layer of material  310  and the second layer of material  312  is reduced. The reduction in offset in the first planar direction causes the second set of apertures  318  to become at least partially vertically aligned (aligned in the z-direction) with the first set of apertures  316 . Further, because the folds  322  generally stand partially upright or upright in the second or third state, a smaller percentage of the surface area of the first surface  311  of the third layer of material  314  may be positioned adjacent to the first surface  305  of the first layer of material  310  as compared to when the apparel layer system  300  is in the first state. 
     This is depicted more clearly in  FIG.  5    which depicts a top view of the apparel layer system  300  when the apparel layer system  300  is in, for instance, the third state as shown in  FIG.  1 C . As shown in  FIG.  5   , the second layer of material  312  is offset from the first layer of material  310  in the first planar direction by a second amount  510 . Further, the apertures  318  of the second layer of material  312  are offset from the apertures  316  in the first layer of material  310  in the first planar direction by the second amount  510  (as measured from the center of each aperture  316 / 318 ). In example aspects, the second amount of offset  510  in the first planar direction is less than the first amount of offset  410  causing the apertures  316 / 318  to become aligned or at least partially aligned in the x-direction and the z-direction. To describe it a different way, there is a greater percentage of overlap between the apertures  316 / 318  in the third state (e.g., greater than, for instance, 90% overlap). Thus, in the third state, there is generally a direct communication path between the first layer of material  310  and the second layer of material  312  such that air may flow through the different layers  310 / 312 . Further, as explained above, in some example aspects, the third layer of material  314  may be formed of a mesh material to facilitate the flow of air between the different layers  310 / 312 / 314 . As mentioned earlier, it is contemplated herein that additional states between the first state and the third state may be achieved so that a customizable level of air permeability may be provided. 
     When the apparel layer system  300  is further used to provide radiant warming in addition to permeability (i.e., when the first surface  311  of the third layer of material  314  comprises a reflective deposit), transitioning the apparel layer system  300  to the second or third state causes a smaller percentage of the surface area of the first surface  311  of the third layer of material  314  to be exposed or oriented to the body surface of a wearer. This is because the folds  322  stand generally upright in the second and third states. In other words, in the second or third state, the third layer of material  314  no longer extends in the first planar direction. Because there is a smaller percentage of the reflective first surface  311  exposed or oriented to the body surface of the wearer, less radiant heat is reflected back to the wearer. 
     An alternative configuration for an apparel layer system in accordance with aspects herein is provided in  FIG.  6    and  FIGS.  7 A- 7 B .  FIG.  6    depicts an exploded view of an apparel layer system  600  comprising a first layer of material  610  and a second layer of material  612 . Instead of a third layer of material formed into a series of folds, the apparel layer system  600  comprises a plurality of discrete panels  614 ,  616 ,  618 , and  620 . Each of the panels  614 ,  616 ,  618 , and  620  is defined by at least a first longitudinal edge  622  and a second longitudinal edge  624  (shown for panel  614 ) opposite the first longitudinal edge  622 . When assembled, each panel&#39;s respective first edge  622  is affixed to the second layer of material  612  along at least a portion of the length of the first edge  622  by, for instance, stitching, bonding, welding, adhesives, and the like. Further, each panel&#39;s respective second edge  624  is affixed to the first layer of material  610  along at least a portion of the length of the second edge  624 . 
     Depending on if the apparel layer system  600  is configured to provide variable levels of permeability, apertures may be provided in the first and second layers of material  610  and  612 . Further, apertures may also be provided in some or all of the panels  614 ,  616 ,  618 , and  620 , or the panels  614 ,  616 ,  618 , and  620  may be formed from a mesh material to facilitate air flow between the layers  610 / 612 . If the apparel layer system  600  is configured to provide warming, the panels  614 ,  616 ,  618 , and  620  may have a reflective material deposited on at least a surface  613 , where the surface  613  is configured to be positioned adjacent to a surface  605  of the first layer of material  610 . Apertures may be absent when the apparel layer system  600  is used for insulation. 
     Side views of the apparel layer system  600  are provided in  FIGS.  7 A and  7 B  where  FIG.  7 A  illustrates the apparel layer system  600  in a first state, and  FIG.  7 B  illustrates the apparel layer system  600  in a second state. With respect to  FIG.  7 A , the first layer of material  610  extends in a first planar direction (e.g., in an x, y reference plane) as indicated by Cartesian coordinate system  714 . Similarly, the second layer of material  612  also extends in the first planar direction and is parallel to and offset from the first layer of material  610 . The panels  614 ,  616 ,  618 , and  620  (shown from the side in  FIGS.  7 A and  7 B ) are positioned between the first and second layers of material  610 / 612 . Each panel&#39;s respective first edge  622  is affixed to an inner surface of the second layer of material  612 , and each panel&#39;s respective second edge  624  is affixed to the surface  605  of the first layer of material  610 . 
     In the first state, and as shown in  FIG.  7 A , the first layer of material  610  is offset in the first planar direction from the second layer of material  612  by a first amount  710 . More particularly, with respect to a particular panel such as the panel  618 , the first edge  622  is offset in the first planar direction from the second edge  624  by the first amount  710 . Further, in the first state, the second layer of material  612  is offset in a second direction perpendicular to the first planar direction (i.e., in a positive z-direction) by a first amount  712 . It is contemplated herein, that in the first state, the panels  614 ,  616 ,  618 , and  620  generally lie flat such that the panels  614 ,  616 ,  618 , and  620  extend in, for instance, the positive x-direction. For clarity, the panels  614 ,  616 ,  618 , and  620  in  FIG.  7 A  are not shown lying completely flat. More particularly, each panel&#39;s respective first edge  622  extends in the positive x-direction, and each panel&#39;s respective second edge  624  extends in the negative x-direction. Further, in the first state, an angle, e, formed between a respective panels, such as the panel  618 , and the second layer of material  612  may be less than, for example, 10 degrees. 
     Similar to the apparel layer system  100 , the apparel layer system  600  can be transitioned to the second state by exerting a tensioning force on the adjustment mechanism  626  in the negative x-direction. This causes the second layer of material  612  to move relative to the first layer of material  610 . And due to the selective attachment of each panel&#39;s respective first edges  622  to the second layer of material  612 , and due to the selective attachment of each panel&#39;s respective second edges  624  to the first layer of material  610 , movement of the second layer of material  612  causes a corresponding movement of the first edges  622  of the panels  614 ,  616 ,  618 , and  620  in the negative x-direction. The second edges  624  generally remain stationary and function as anchor points. 
     In the second state, the first layer of material  610  is offset in the first planar direction from the second layer of material  612  by a second amount  715  which is less than the first amount  710 . More particularly, and again with respect to the panel  618 , the first edge  622  is offset in the first planar direction for the second edge  624  by the second amount  715 . In example aspects, the second amount of offset  715  between, for instance, the first edge  622  and the second edge  624  of a particular panel may be zero or near zero. Further, in the second state, the second layer of material  612  is offset in the second direction perpendicular to the first planar direction (i.e., in a positive z-direction) by a second amount  716  that is greater than the first amount  712 . It is contemplated herein, that in the second state, the panels  614 ,  616 ,  618 , and  620  generally are positioned upright such that the panels  614 ,  616 ,  618 , and  620  extend in, for instance, the second direction (e.g., the z-direction). Further, in the second state, the angle, e, formed between a respective panel, such as the panel  618 , and the second layer of material  612  may be greater than, for example, 10 degrees, and/or may be between 75 degrees and 90 degrees. When the angle, e, is 90 degrees, a maximum amount of offset in the second direction (the positive z-direction) is achieved. Thus, as seen, although the apparel layer system  600  utilizes separate panels instead of a folded, unitary material as in the apparel layer system  100 , the apparel layer system  600  functions in much that same way to provide variable levels of insulation, warming, or permeability. 
     With respect to the adjustment mechanism that is coupled to the second layer of material, aspects herein contemplate a number of different mechanisms such as pull tabs and/or slider assemblies. One example mechanism  800  that utilizes strips or tapes of material having alternating and repeating magnetic elements (commonly known as multi-pole magnet strips) is depicted in  FIGS.  8 A- 8 C  in accordance with aspects herein. The mechanism  800  comprises a first textile material  810  to which a first magnetic strip  812  is affixed. The first textile material  810  may correspond to the second layer of material  112 . In the aspect depicted in  FIGS.  8 A- 8 C , the first magnetic strip  812  comprises a magnetic tape having first and second magnetic elements (i.e., North and South poles)  816  arranged in an alternating and repeating pattern. In example aspects, the first magnetic strip  812  may be covered by a textile for a cleaner aesthetic and a better hand feel. Further, a reinforced portion may be located at one end of the textile (e.g., the end opposite that affixed to the first textile material  810 ) for easy grasping by a wearer. 
     The mechanism  800  further comprises a second magnetic strip  814  having first and second magnetic elements (i.e., North and South poles)  818  arranged in an alternating and repeating pattern. The second magnetic strip  814  may be affixed to a second textile material (not shown). The second textile material may comprise part of a garment to which an apparel layer system is incorporated and/or may comprise a first layer of material of an apparel layer system such as the first layer of material  110  of  FIGS.  1 A- 1 C . It is contemplated herein, that the second magnetic strip  814  is configured to be maintained in a relatively fixed position. 
       FIG.  8 A  depicts the first magnetic strip  812  and the second magnetic strip  814  held in contact with each other due to the attraction force between magnetic elements  816  and magnetic elements  818  having opposite polarity. To describe it differently, the first magnetic strip  812  is in contact with the second magnetic strip  814  due to the vertical alignment (alignment in the z-direction) of magnetic elements having opposite polarity. The positioning of the first and second magnetic strips  812 / 814  in  FIG.  8 A  may correspond to, for example, a first state of an apparel layer system such as the first state shown in  FIG.  1 A  for the apparel layer system  100 . Movement (e.g., lateral movement) of the first magnetic strip  812  relative to the second magnetic strip  814  may be initiated by a mechanical pulling force  820  (e.g., a wearer&#39;s fingers) on the first magnetic strip  812 , where the pulling force  820  has sufficient magnitude to overcome the attraction force between the magnetic elements  816  located on the first magnetic strip  812  and the magnetic elements  818  located on the second magnetic strip  814 . 
     As shown in  FIG.  8 B , once the mechanical pulling force  820  is initiated, the movement of the first magnetic strip  812  is constrained by the second magnetic strip  814  such that the two strips  812 / 814  are maintained in a close but spaced-apart relationship. For instance, as shown in  FIG.  8 B , the repulsion force between magnetic elements  816  and magnetic elements  818  having the same polarity causes the strips  812 / 814  to repulse each other so that the strips  812 / 814  remain disengaged. But the attraction force between magnetic elements  816  and magnetic elements  818  having opposite polarity helps to keep the strips  812 / 814  in a close, spaced-apart relationship to each other (i.e., they do not become completely disengaged such that a wearer would need to re-engage the strips  812 / 814  with each other). To describe this in a different way, the first magnetic strip  812  is disengaged from the second magnetic strip  814  when magnetic elements having the same polarity are in vertical alignment (i.e., aligned in the z-direction). 
     Because the strips  812 / 814  comprise alternate and repeating magnetic elements, the first magnetic strip  812  is able to slidably move relative to the second magnetic strip  814  in discrete, incremental steps. Stated differently, the slidable movement of the first magnetic strip  812  relative to the second magnetic strip  814  is guided by the alternating and repeating magnetic elements  816 / 818  of the strips  812 / 814 . Once a desired shift of the first textile material  810  is achieved, the first magnetic strip  812  can be “locked in place” or made to contact the second magnetic strip  814  by allowing the magnetic elements  816  of the first magnetic strip to engage with the magnetic elements  818  of the second magnetic strip  814  that have opposite polarity. This occurs, as described above, when the magnetic elements having opposite polarity are in vertical alignment with each other. This aspect is shown in  FIG.  8 C  and may correspond to, for instance, the second state shown in the  FIG.  1 B  for the apparel layer system  100  or the third state shown in  FIG.  1 C . 
     The use of this configuration enables the first textile material  810  to be shifted in incremental steps in relation to, for example, the first layer of an apparel layer system. In turn, this allows for the fine-tuning of insulation, warming, or permeability levels of a garment incorporating the apparel layer system described herein. Although four magnetic elements are depicted for each strip  812 / 814 , it is contemplated herein that the strips  812 / 814  may comprise a fewer or greater number of magnetic elements. Any and all aspects, and any variation thereof, are contemplated as being within aspects herein. 
     Although the mechanism  800  is shown as comprising magnetic strips having alternating and repeating magnetic elements, a somewhat similar function may be achieved by using complementary tapes having, for example, a stud on one of the tapes and repeating sockets on the complementary tape (or vice versa), a button on one of the tapes and repeating button holes on the complementary tape (or vice versa), hooks on one of the tapes and loops on the complementary tape (e.g., a hook-and-loop fastener system), and the like. The functional effect produced by these different mechanisms would be similar to the use of the magnetic strips in that an incremental adjustment of a second layer of material relative to a first layer of material may be achieved. 
     A different type of adjustment mechanism is shown in  FIGS.  9 A and  9 B  and is referenced generally by the numeral  900 . With respect to  FIG.  9 A , a second layer of material  910 , such as the second layer of material  112  of  FIGS.  1 A- 1 C , is shown having a first set of slider elements  912  (for example, zipper teeth) attached to a perimeter edge of the second layer of material  910 . This may occur by affixing the first set of slider elements  912  to the second layer of material  910  using a tape or by directly affixing the slider elements  912  to the second layer of material  910 . A slider pull  914  is also shown coupled to the first set of slider elements  912 . The second layer of material  910  may be part of an apparel layer system further comprising a first layer of material  916  and a third layer of material  918  formed into a series of folds as described in relation to  FIGS.  1 A- 1 C  and as shown in  FIG.  9 A  or a plurality of separate panels as described in relation to  FIG.  6    and  FIGS.  7 A- 7 B . 
     The adjustment mechanism  900  further comprises a second set of slider elements  920  affixed to a garment panel  922  (in example aspects, the first layer of material  916  may also comprise the garment panel  922 ). The second set of slider elements  920  are positioned to be in parallel alignment with the first set of slider elements  912  and may be affixed to the garment panel  922  via a tape or by directly affixing the slider elements  912  to the garment panel  922 .  FIG.  9 A  depicts the second layer of material  910  in a first position relative to the first layer of material  916 . This may be similar to the first state shown in  FIG.  1 A  for the apparel layer system  100  or the first state shown in  FIG.  7 A  for the apparel layer system  600 . 
       FIG.  9 B  depicts the second layer of material  910  in a second position relative to the first layer of material  916 . This may correspond to, for example, the second state or the third state shown in  FIGS.  1 A and  1 B  respectively for the apparel layer system  100  or the second state or third state shown in  FIG.  7 B  for the apparel layer system  600 . To transition the second layer of material  910  to the second position, the first set of slider elements  912  may be engaged with the second set of slider elements  920  using, for instance, the slider pull  914 . Because the second set of slider elements  920  are coupled to the stationary garment panel  922 , the second layer of material  910  is shifted toward the second set of slider elements  920  in order to engage the slider elements  912 / 920 . As described above for the apparel layer system  100 , the shift of the second layer of material  910  causes the folds of the third layer of material  918  to become more upright causing a greater offset in the z-direction between the first layer of material  916  and the second layer of material  910 . A similar result occurs when the third layer of material is in the form of discrete panels. 
       FIGS.  14 A and  14 B  depict yet another adjustment mechanism  1400  in accordance with aspects herein. With respect to  FIG.  14 A , this figure depicts the adjustment mechanism  1400  in a first state. The adjustment mechanism  1400  comprises a first portion  1410  coupled to a layer of material  1412  such as, for example, the second layer of material  112  of the apparel layer system  100  (additional layers of the apparel layer system are not shown). In example aspects, the first portion  1410  may be a knit or woven structure formed from yarns  1414  that dimensionally transform upon exposure to a stimulus such as moisture. For example, the yarns  1414  may comprise a bi-component yarn formed from polyester and nylon that crimps or curls when exposed to the stimulus. The yarns  1414  are oriented in the first portion  1410  such that their long axes are perpendicular to, for example, the long axes of the folds (or panels) formed from a third layer of material of an apparel layer system (i.e., the third layer of material  114  of the apparel layer system  100 ). 
     Continuing, the first portion  1410  of the adjustment mechanism  1400  may be fixedly attached to a second portion  1416 . The second portion  1416  may be affixed to a second textile material (not shown). The second textile material may comprise part of a garment to which an apparel layer system is incorporated and/or may comprise a first layer of material of an apparel layer system such as the first layer of material  110  of  FIGS.  1 A- 1 C . It is contemplated herein, that the second portion  1416  is configured to be maintained in a relatively fixed position. 
       FIG.  14 B  illustrates the adjustment mechanism  1400  after exposure to a stimulus. The stimulus may comprise water or other types of moisture, light, magnetic fields, a change in temperature, and the like. Upon exposure to the stimulus, the yarns  1414  may crimp or curl causing the first portion  1410  to shorten in length. In other words, the stimulus may cause the yarns  1414  to undergo a dimensional transformation where the dimensional transformation is a shortening in the length of the yarns  1414 . Because the first portion  1410  is fixedly secured to the layer of material  1412 , a shortening of the first portion  1410  causes the layer of material  1412  to shift toward the second portion  1416 . As described above for the apparel layer system  100 , the shift of the layer of material  1412  in the negative x-direction causes the folds of the third layer of material to become more upright causing a greater offset in the z-direction between the layer of material  1412  and a first layer of material (not shown). A similar result occurs when the third layer of material is in the form of discrete panels. It is contemplated herein that instead of just a single first portion  1410  there may be multiple first portions each affixed to the layer of material  1412  as shown and formed from the yarns  1414  Additional adjustment mechanisms beyond those shown and described are contemplated as being within aspects herein. Any adjustment mechanism that causes, upon mechanical manipulation of the adjustment mechanism, a shifting of a second textile layer relative to a first textile layer is contemplated as being within aspects herein. 
       FIG.  10    depicts a front perspective view of an apparel layer system incorporated into a garment in accordance with aspects herein. The apparel layer system is indicated by reference numeral  1010 , and the garment is indicated by reference numeral  1000 . The garment  1000  is shown as an upper body garment and is further shown as a vest-type structure without sleeves. Although shown as a vest without sleeves, it is contemplated herein that the garment  1000  may comprise other types of upper body garments such as a pullover, a hoodie, a long-sleeve short, a short-sleeved shirt, and the like. The garment  1000  may also comprise a support garment such as a bra. It is also contemplated herein that the apparel layer system  1010  may be incorporated into apparel items and equipment meant to be worn by a wearer such as, for example, hats, socks, shin guards, compression sleeves, pads, and the like. Any and all aspects, and any variation thereof, are contemplated as being within aspects herein. 
     The apparel layer system  1010  is shown as being positioned on a front right aspect of the garment  1000  and on a front left aspect of the garment  1000 . These locations are illustrative only, and it is contemplated herein that the apparel layer system  1010  may be positioned on the garment  1000  in other locations based on the function of the apparel layer system  1010 . For instance, when the apparel layer system  1010  is configured to provide variable levels of air permeability, such as the apparel layer system  300 , the apparel layer system  1010  may be positioned on the garment  1000  such that it is configured to be adjacent to high heat or sweat producing areas of the wearer when the garment  1000  is worn. Example locations may comprise, for example, an upper center back area, a lower center back area, and an upper front chest area. When the apparel layer system  1010  is configured to provide variable levels of insulation and/or radiant warming, such as the apparel layer system  200 , the apparel layer system  1010  may be positioned on the garment  1000  such that it is configured to be adjacent to low heat producing, or high heat loss areas of the wearer when the garment  1000  is worn such as, for example, a lower front chest area, a head area, an arm area, and the like. When the apparel layer system  1010  is configured to provide both permeability and radiant warming, the apparel layer system  1010  may be positioned adjacent to high heat and/or sweat producing areas with the thought that the warming function of the apparel layer system  1010  may be “turned off” once the wearer begins exercising. 
     With respect to the apparel layer system  1010 , the apparel layer system  1010  may comprise a second layer of material  1012 , an adjustment mechanism  1013  coupled to the second layer of material  1012 , a first layer of material  1014 , and a third layer of material  1016  positioned between the first layer of material  1014  and the second layer of material  1012 . The second layer of material  1012  may comprise the second layer of material  112  of  FIGS.  1 A- 1 C  and is shown as being positioned on an outer-facing surface of the garment  1000 . That is, the second layer of material  1012 , in example aspects, may be configured to face an external environment or one or more additional layers positioned external to the garment  1000 . The first layer of material  1014  may comprise the first layer of material  110  of  FIGS.  1 A- 1 C  and is shown as being positioned internal to the second layer of material  1012 . As such, the first layer of material  1014  may be configured to face a body surface of a wearer when the garment  1000  is worn. As used herein, the term “body surface” may mean an actual skin surface of a wearer or it may mean one or more additional layers positioned internal to the first layer of material  1014 . A second mechanism  1015 , complementary to the adjustment mechanism  1013  is depicted as being coupled to the garment  1000  and/or to the first layer of material  1014 . 
     It is contemplated herein that the apparel layer system  1010  may be incorporated into the garment  1000  as a panel or trim piece. That is, perimeter edges of at least the second layer of material  1012  and the first layer of material  1014  may be coupled to the garment  1000 . In one example, a cut-out having the perimeter shape of the apparel layer system  1010  may be formed in the garment  1000 , and the apparel layer system  1010  may be positioned within the cut-out and the perimeter edges of the apparel layer system  1010  may be affixed to the edges of the cut-out. In another implementation example, the apparel layer system  1010  may be positioned over the panel material of the garment  1000  and the perimeter edges of the apparel layer system  1010  may be affixed to the underlying panel material. 
     In yet another implementation example, the first layer of material  1014  may comprise an integral extension of the panel material forming the garment  1000 . That is, instead of the first layer of material  1014  comprising a piece separate from the garment  1000 , it may comprise the panel material forming the garment  1000 . In this example, the third layer of material  1014  and the second layer of material  1012  would be affixed to the garment  1000  at a desired location to form the apparel layer system  1010 . In yet another implementation example, the first layer of material  1014 , the second layer of material  1012 , and/or the third layer of material  1016  may all be integrally formed from the panel material forming the garment  1000 . That is the panel material forming the garment  1000  may be created through a knitting or weaving process. The knitting or weaving process may be modified to, for instance, form at least the first layer of material  1014 , the second layer of material  1012 , and/or the third layer of material  1016 . Any and all aspects, and any variation thereof, are contemplated as being within aspects herein. 
       FIG.  11    illustrates and apparel layer system incorporated into a lower-body garment in accordance with aspects herein. The lower-body garment is indicated by reference numeral  1100 , and the apparel layer system is indicated by the reference numeral  1110 . Many of the aspects of the apparel layer system  1010  such as construction details, implementation details, and placement based on insulation needs and permeability needs are applicable to the apparel layer system  1110  and, as such, will not be repeated for brevity sake.  FIG.  11    is provided to illustrate that apparel layer systems may also be incorporated into lower-body garments. Although shown as a pair of long pants, it is contemplated herein that the garment  1100  may be in the form of a short, a capri, a legging, a tight, and the like. 
     The apparel layer system  1110  is shown positioned over a front, upper aspect of respective leg portions of the garment  1100 . These areas correspond to the upper thigh area of a wearer when the garment  1100  is worn. As previously set forth, the apparel layer system  1110  may be configured to provide variable insulation levels, variable warming levels, or to provide variable air permeability levels. Although shown as being positioned at the front, upper aspect of the lower-body garment  1100 , it is contemplated herein that the apparel layer system  1110  may also be positioned at other locations on the lower-body garment  1100  depending on where insulation, warming, or air permeability is desired. Any and all aspects, and any variation thereof, are contemplated as being within aspects herein. 
     Turning now to  FIG.  12   , an apparel layer system  1200  is depicted in accordance with aspects herein.  FIG.  12    is provided to illustrate one way of positioning the third layer of material (referenced here by the numeral  1210  and shown by dashed lines to indicate it is hidden from view) between a first layer of material  1212  (also shown by dashed lines to indicate it is hidden from view) and a second layer of material  1214  so that the ends  1215  of the folds  1216  of the third layer of material  1210  are not exposed. This may be advantageous when the apparel layer system  1200  is used to provide variable levels of the insulation. In this use case, it would not necessarily be desirable to have the ends  1215  of the third layer of material  1210  exposed because they would potentially act as egress points for warmed air to leave the apparel layer system  1200 . To overcome this, the third layer of material  1210  may be sized smaller than the first layer of material  1212  and the second layer of material  1214 . That is, the perimeter shape of the third layer of material  1210  may be smaller (e.g., less width and less length) than the first and second layers of material  1212 / 1214 . The third layer of material  1210  is positioned between the first and second layers  1212 / 1214  such that the respective edges of the first and second layers of material  1212 / 1214  are affixed directly together. The result of this construction is a “sealed” space which may help to retain any warmed air in order to provide effective insulation. In an alternative construction where the first layer of material  1212  forms at least a portion of an underlying garment or apparel item, the respective edges of the second layer of material  1214  would be secured to the first layer of material  1212 . 
       FIG.  13    depicts a flow diagram of an example method  1300  for forming an apparel layer system in accordance with aspects herein. The apparel layer system may comprise, for example, the apparel layer system  100 ,  200 , or  300 . At a first step  1310 , a first layer of material is provided. When the apparel layer system is intended to be used to provide variable levels of insulation and/or radiant warming, the first layer of material may comprise, for example, a tightly woven material or even a non-woven material such as a felt or other similar materials. When the first layer of material is intended to provide variable levels of air permeability and/or radiant warming, the first layer of material may comprise a knit material with or without apertures. For instance, when formed without engineered apertures, the knit material may comprise a loosely knit material. The material may also comprise a woven, or non-woven material having apertures. In example aspects, the first layer of material may also be used to form a garment or apparel item incorporating the apparel layer system. 
     At a step  1312 , a second layer of material is provided. Similar to the first layer of material provided at the step  1310 , when the apparel layer system is intended to be used to provide variable levels of insulation and/or warming, the second layer of material may comprise, for example, a tightly woven material or even a non-woven material such as a felt or other similar materials. When the second layer of material is intended to be used to provide variable levels of air permeability and/or radiant warming, the second layer of material may comprise a knit material with or without apertures. For instance, when formed without engineered apertures, the knit material may comprise a loosely knit material. The material may also comprise a woven, or non-woven material having apertures. 
     At a step  1314 , a third layer of material is provided. When the apparel layer system is used to provide variable levels of insulation, the third layer of material may comprise a tightly woven material or a non-woven material such as felt or other similar materials. When the third layer of material is intended to provide variable levels of air permeability, the third layer of material may comprise a knit material, a mesh material, and/or a woven or non-woven material with apertures. And when the third layer of material is intended to provide variable levels of radiant warming, at least a first surface of the third layer of material may comprise a reflective surface. In this aspect, the reflective surface of the third layer of material is positioned adjacent to a first surface of the first layer of material. As described in relation to  FIGS.  6 ,  7 A, and  7 B , it is also contemplated herein that the third layer of material may comprise a plurality of discrete panels. Any and all aspects, and any variation thereof, are contemplated as being within aspects herein. 
     When the third layer of material is provided as a unitary panel, at a step  1316 , the third layer of material is manipulated to form a series of parallel folds. Each fold may comprise a first apex region and a second opposite apex region. At a step  1318 , the third layer of material is selectively attached to the first layer of material. More specifically, the first apex regions of the folds of the third layer of material are affixed to a surface of the first layer of material using, for example, stitching, adhesives, welding, bonding, and the like. At a step  1320 , the third layer of material is further selectively attached to the second layer of material. More specifically, the second apex regions of the folds of the third layer of material are affixed to a surface of the second layer of material using, for instance, stitching, adhesives, welding, bonding, and the like. 
     In an alternative aspect where the third layer of material is provided as a plurality of discrete panels, each panel may be defined by at least a first lengthwise edge and a second lengthwise edge. The first lengthwise edge of each of the panels is affixed to a surface of the first layer of material using one or more of the affixing technologies discussed in steps  1318  and  1320 . Similarly, the second lengthwise edge of the each of the panels is affixed to a surface of the second layer of material using affixing technologies discussed herein. 
     At a step  1322 , an adjustment mechanism is coupled to a perimeter edge of the second layer of material. Example adjustment mechanisms may comprise, for example, a magnetic tape having alternating and repeating magnetic elements configured to mate with a complementary magnetic tape having alternating and repeating magnetic elements that is coupled to a garment incorporating the apparel layer system. Other example adjustment mechanisms that may utilize complementary tapes where one tape is affixed to the second layer of material and the other tape is affixed to the garment may comprise hook-and-loop fasteners, button and button holes, snaps and sockets, hooks and eyes, and the like. Another adjustment mechanism contemplated herein may comprise a first set of slider elements coupled to the second layer of material and a second set of slider elements coupled to the garment. Yet another adjustment mechanism contemplated herein comprises a material portion coupled to the second layer of material and formed from yarns that undergo a shortening in length upon exposure to a stimulus. Any and all aspects, and any variation thereof, are contemplated as being within aspects herein. 
     Additional steps for the method  1300  may comprise incorporating the apparel layer system into a garment. In one example aspect used when the apparel layer system comprises a panel piece, the perimeter edges of at least the first layer of material and the second layer of material may be affixed to the garment. In another example aspect used when the first layer of material comprises a garment panel, the apparel layer system may be incorporated by affixing the second layer of material and the third layer of material to the first layer of material. Any and all aspects, and any variation thereof, are contemplated as being within aspects herein. 
     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 invention. 
     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.