WO2009058720A1

WO2009058720A1 - Articles of footwear

Info

Publication number: WO2009058720A1
Application number: PCT/US2008/081292
Authority: WO
Inventors: James Cheney; David Thorpe
Original assignee: The Keds Corporation
Priority date: 2007-10-29
Filing date: 2008-10-27
Publication date: 2009-05-07
Also published as: US20090107012A1

Abstract

Articles of footwear are configured to provide functionally correct and predetermined amounts of stretch in functionally correct locations, thus providing comfort to a wearer, while retaining a pleasing aesthetic appearance in use. For example, an article of footwear (10) includes an upper assembly (20) having a first layer (40) coextensive with a second layer (42). The first layer includes a first material having a first 30 % modulus, and the second layer includes at least one first region (44, 44') (e.g., a stretch region) and at least one second region (50) (e.g., a non-stretch region). The at least one first region includes a second material having a second 30 % modulus lower than the first 30 % modulus. The at least one second region includes a third material having a third 30 % modulus higher than both the first 30 % modulus and the second 30 % modulus.

Description

Articles of Footwear

TECHNICAL FIELD [0001] This disclosure relates to articles of footwear.

BACKGROUND [0002] In general, shoes include an upper portion and a sole. When the upper portion is secured to the sole, the upper portion along with the sole defines a void that is configured to securely and comfortably hold a human foot. Often, the upper portion and/or sole are/is formed from multiple layers that can be stitched or adhesively bonded together. For example, the upper portion can be made of a combination of leather and fabric, or foam and fabric, and the sole can be formed from at least one layer of synthetic rubber. Often materials are chosen for functional reasons, e.g., water-resistance, durability, abrasion-resistance, and breathability, while shape, texture, and color are used to promote the aesthetic qualities of the shoe.

SUMMARY [0003] The present disclosure describes articles of footwear (e.g., shoes, sandals, boots, etc.) that have controlled and predetermined amounts of stretch in functionally correct locations, providing comfort to a wearer, while retaining a pleasing aesthetic appearance in use. In general, an article of footwear includes a lower assembly comprising a sole assembly and an upper assembly attached to the sole assembly. The upper and lower assemblies together define a void for receiving a foot. The upper assembly includes a first layer and a second layer coextensive (i.e., having generally the same boundaries and shape) with the first layer. The upper assembly may be configured to provide one or more regions of controlled and/or predetermined amounts of stretch. In some examples, the upper assembly includes first, second, and third layers arranged and configured to provide one or more stretch control regions.

[0004] In one aspect, the first layer includes a first material, such as a woven fabric formed of cotton and Lycra, having a first 30% modulus (tensile strength at 30% elongation); and the second layer includes at least one first region (e.g., a stretch region) and at least one second region (e.g., a non-stretch region). The at least one first region includes a second material, such as a knit mesh formed of polyester and spandex, having a second 30% modulus lower than the first 30% modulus. The at least one second region includes a third material (e.g., a single material or a composite material), such as a polyurethane film or a stitched-on relatively non-stretchable fabric (e.g., woven nylon), having a third 30% modulus higher than both the first 30% modulus and the second 30% modulus. In the example of a polyurethane film as the third material, the polyurethane film may be impregnated into the second material. In the case of the non-stretchable fabric as the third material, the non-stretchable fabric may be stitched onto the second material. Any such article of footwear can have multiple stretch and non-stretch regions. In some implementations of this aspect, selection of the first material of the first layer controls the overall level of stretch of the upper. The second layer is used for determining the locations of the regions of certain amounts of allowed stretch, and the selection of the second material determines the amount of allowed stretch. The location of the second region and the selection of the third material determines the location a relatively non-stretchable region and the amount of non-stretch.

[0005] Implementations of this aspect of the disclosure may include one or more of the following features. In some implementations, the first 30% modulus is less than 2 kg/cm, and is preferably between about 0.2 kg/cm and about 1.9 kg/cm. In some examples, the second 30% modulus is less than about 0.3 kg/cm, and is preferably between about 0.04 kg/cm and about 0.25 kg/cm. The third 30% modulus may be greater than about 2.0 kg/cm.

[0006] In another aspect, the first layer includes a first material, such as a woven fabric formed of cotton and Lycra, having a first 30% modulus (tensile strength at 30% elongation); and the second layer includes at least one first region (e.g., a stretch region) and at least one second region (e.g., a non-stretch region). The at least one first region includes a second material, such as a knit mesh formed of polyester and spandex, having a second 30% modulus higher than the first 30% modulus. The at least one second region includes a third material (e.g., a single material or a composite material), such as a polyurethane film or a stitched-on relatively non-stretchable fabric (e.g., woven nylon), having a third 30% modulus higher than both the first 30% modulus and the second 30% modulus. In some implementations of this aspect, selection of the first material of the first layer controls the overall level of stretch of the upper. The second layer is used for determining the locations of the regions of certain amounts of relatively less stretch, and the selection of the second material determines the reduction of allowed stretch. The location of the second region and the selection of the third material determines the location a relatively non-stretchable region and the amount of non-stretch. [0007] Implementations of this aspect of the disclosure may include one or more of the following features. In some implementations, the first 30% modulus is less than 2 kg/cm, and is preferably between about 0.2 kg/cm and about 1.9 kg/cm. In some examples, the second 30% modulus is greater than 2 kg/cm. The third 30% modulus may be greater than about 2.0 kg/cm as well. [0008] Implementations of the disclosure may include one or more of the following features. In some implementations, the article of footwear includes a third layer, such as a liner, comprising a fourth material having a fourth 30% modulus less than the first 30% modulus. The second layer may be interposed between the first and third layers. In some examples, the first layer has a thickness of less than about 0.200 inch (5 mm) and the second layer has a thickness of less than about 0.200 inch (5 mm). The third layer may have a thickness of less than about 0.080 inch (2 mm). [0009] In some implementations, the at least one second region comprises a polymer film, a non-stretch fabric or other textile material, such as a woven nylon material, a knit fabric, non-woven fabric, coated fabric, leather, etc., and/or thread stitched in a pattern that restricts stretch. The first and/or second layers may comprise a knit material, a woven material, such as a twill material, a non-woven material, a coated fabric, and/or a leather material.

[0010] In another aspect, an article of footwear includes a lower assembly comprising a sole assembly and an upper assembly attached the sole assembly. The upper and lower assemblies together define a void for receiving a foot. The upper assembly includes a first layer and a second layer coextensive with the first layer. The second layer defines a plurality of slits in at least one stretch control region defined by the second layer. The slits may be visible or hidden from exterior view. [0011] Implementations of this aspect of the disclosure may include one or more of the following features. In some implementations, the article of footwear defines a longitudinal axis, and the slits are arranged to run substantially parallel to the longitudinal axis. In some examples, the first layer includes a first material having a first 30% modulus and the second layer includes a second material having a second 30% modulus higher than the first 30% modulus. In some implementations, the article of footwear includes a third layer having a third 30% modulus lower than both the first 30% modulus and the second 30% modulus.

[0012] In yet another aspect, a method of making an upper of an article of footwear includes selecting a first sheet material having a first 30% modulus, selecting a second sheet material having a second 30% modulus lower than the first 30% modulus, and applying a stretch control material, such as a polyurethane, a relatively non-stretchable fabric or even an arrangement of stitching, having a third 30% modulus higher than the first and the second 30% modulus to the second sheet material to form at least one stretch control region of the second sheet material. The method also includes arranging the first sheet material and the second sheet material to be coextensive with each other. In some cases, the first and/or second sheet materials having stretch characteristics (e.g., one or two dimensional stretching) and the at least one stretch control region reduces or eliminates the stretching ability of the second sheet material along one or more directions (e.g., longitudinal and transverse with respect to the article of footwear). In some implementations, the method includes selecting a third sheet material and arranging the second sheet material between the first sheet material and the third sheet material. The first, second, and third sheet materials are arranged coextensive with each other. [0013] In another aspect, a method of making an upper of an article of footwear includes selecting a first sheet material having a first 30% modulus, selecting a second sheet material having a second 30% modulus higher than the first 30% modulus, and applying a stretch control material, such as a polyurethane, a relatively non-stretchable fabric or even an arrangement of stitching, having a third 30% modulus higher than the first and the second 30% modulus to the second sheet material to form at least one stretch control region of the second sheet material. The method also includes arranging the first sheet material and the second sheet material to be coextensive with each other. In some cases, the first and/or second sheet materials having stretch characteristics (e.g., one or two dimensional stretching) and the at least one stretch control region reduces or eliminates the stretching ability of the second sheet material along one or more directions (e.g., longitudinal and transverse with respect to the article of footwear). In some implementations, the method includes selecting a third sheet material and arranging the second sheet material between the first sheet material and the third sheet material. The first, second, and third sheet materials are arranged coextensive with each other. [0014] In another aspect, a method of making an upper of an article of footwear includes selecting a first sheet material having a first 30% modulus, selecting a second sheet material having a second 30% modulus higher than the first 30% modulus, and forming slits through the second sheet material to provide at least one stretch control region. The at least one stretch control region may be stretchable along a direction generally perpendicular to the slits. In some cases, the first and/or second sheet materials having stretch characteristics (e.g., one or two dimensional stretching) and the slits accentuate the stretch characteristics of the second sheet material along a direction generally perpendicular to the slits. In some implementations, the method includes arranging the first sheet material and the second sheet material to be coextensive with each other. The method may include selecting a third sheet material and arranging the second sheet material between the first sheet material and the third sheet material, with the first, second, and third sheet materials being coextensive with each other.

[0015] The shoes provide an amount of stretch in regions selected to match foot movement; that is, the shoes can provide biomechanically correct levels of stretch. The shoes can provide a customized fit and adjust to the normal swelling of feet over the course of a day. The shoes can reduce fatigue and discomfort of the feet. The shoes provide comfort to the metatarsal and toe area of feet. The controlled and predetermined stretch allows the shoes to retain a pleasing aesthetic appearance in use. [0016] The details of one or more implementations of the disclosure are set forth in the accompanying drawings and the description below. Other features, objects, and advantages will be apparent from the description and drawings, and from the claims.

DESCRIPTION OF DRAWINGS

[0017] FIG. 1 is a side view of a shoe that has regions of controlled and predetermined stretch.

[0018] FIG 2 is a top view of the shoe of FIG. 1.

[0019] FIG. 2A is a sectional view of the shoe of FIG. 2, taken along line 2A-

2A. [0020] FIG. 3 is a top view a shoe that has regions of controlled and predetermined stretch.

[0021] FIG. 3A is a sectional view of the shoe of FIG. 3, taken along line 3A-

3A. [0022] Like reference symbols in the various drawings indicate like elements.

By way of example only, all of the drawings are directed to a shoe suitable to be worn on a right foot. The invention includes also the mirror images of the drawings, i.e. a shoe suitable to be worn on a left foot.

DETAILED DESCRIPTION [0023] Referring to FIG. 1, an article of footwear 10 that has regions of controlled and predetermined stretch includes a shoe lower assembly 12 that includes a sole or sole assembly 14, and a shoe upper assembly 20 connected to and extending from the shoe lower assembly 12. Together, the upper assembly 20 and lower assembly 12 define a void 22 dimensioned to accept a human foot. The article of footwear 10 is shown as a traditional shoe; however, the inventions disclosed and claimed may be employed on other forms of footwear, such as, but not limited to sandals and boots.

[0024] Referring particularly to FIG. 2, the upper assembly 20 includes a toe box region 26, e.g., formed of canvas impregnated with rubber, a first stretch region zone 30, a second stretch zone 32 and a restricted stretch zone 36. The stretch zones 30, 32 allow the shoe 10 to move with the foot as a user walks and prevent or substantially inhibit bunching of the upper assembly 20 in those zones or regions that may cause discomfort. The stretch zones 30, 32 may be generally located in a vamp portion of the upper assembly 20. The restricted stretch zone 36 may be located substantially between the first and second stretch zones 30, 32 and toeward of a lacing region 28.

[0025] Referring now to FIGS. 2 and 2A, the upper assembly 20 includes a first layer 40 that includes a first material, such as a woven fabric formed of cotton and Lycra, having a first 30% modulus (tensile strength at 30% elongation), and a second layer 42 coextensive (i.e., having generally the same boundaries and shape) with the first layer 40. In some implementations, the second layer 42 has first regions 44 and 44' that include a second material having a second 30% modulus lower than the first 30% modulus. In other implementations, the second layer 42 has first regions 44 and 44' that include a second material having a second 30% modulus higher than the first 30% modulus. In some examples, the second material includes a knit mesh formed of polyester and spandex. The second layer 42 also has at least one second region 50 that includes a third material having a third 30% modulus higher than both the first 30% modulus and the second 30% modulus. The third material may include at least one of a polyurethane film, a stitched-on relatively non-stretchable fabric (e.g., woven nylon), and a combination thereof. In the example of a polyurethane film as the third material, the polyurethane film may be impregnated into the second material. In the case of the non-stretchable fabric as the third material, the non-stretchable fabric may be stitched onto the second material. Such a construction can provide biomechanically correct levels of stretch, providing maximum comfort to the wearer. [0026] In implementations where the second material has a second 30% modulus lower than the first 30% modulus, selection of the first material of the first layer 40 controls the overall level of stretch of the upper assembly 20. The second layer 42 is used for determining the locations of the first regions 44 and 44' of certain amounts of allowed stretch. The selection of the second material determines the amount of allowed stretch. The location of the second region 50 and the selection of the third material determines the location a relatively non-stretchable region and the amount of non-stretch. [0027] In implementations where the second material has a second 30% modulus higher than the first 30% modulus, the selection of the first material of the first layer 40 controls the overall level of stretch of the upper assembly 20. The second layer 42 is used for determining the locations of the first regions 44 and 44' of certain amounts of relatively less stretch, and the selection of the second material determines the reduction of allowed stretch. The location of the second region 50 and the selection of the third material determines the location a relatively non-stretchable region and the amount of non-stretch.

[0028] In some implementations, the upper assembly 20 also includes a third layer 54 (as shown in FIG. 2A), such as a foot side liner layer, that includes a fourth material, such as a polyester knit material, having a fourth 30% modulus less than the first 30% modulus. In some implementations, the second layer 42 is interposed between the first 40 and third layers 54 (as shown in FIG. 2A). [0029] The values of a 30% modulus is measured in accordance with ASTM

D5034-01 (Breaking Strength and Elongation of Textile Fabrics - Grab Test) in which the load reading is taken when the test specimen has been stretched to an elongation of 30%. The load reading is measured in kg/cm width of the fabric/material. In some instances, the first 30% modulus is less than about 2.0 kg/cm, e.g., between about 0.2 kg/cm and about 1.9 kg/cm, and the second 30% modulus is less than about 0.30 kg/cm, e.g., between about 0.04 kg/cm and about 0.25 kg/cm. The third 30% modulus can be greater than about 2.0 kg/cm, such as between about 2.5 kg/cm and about 10 kg/cm. The fourth 30% modulus can be less than about 0.3 kg/cm, e.g., between about 0.04 kg/cm and about 0.25 kg/cm.

[0030] In some implementations, the second layer 42 has more than one second region 50 (e.g., relatively non-stretchable region). For example, the second layer 42 can have one, two, three, four, five, six or more, relatively non-stretchable regions 50. In some implementations, the second layer 42 has more than one first region 44, 44' (relatively stretchable region). For example, the second layer 42 can have one, two, three, four, five, six or more, relatively stretchable regions 44, 44'. [0031] In some implementations, the second region 50 includes a film of polyurethane, a polyamide, a polyester, an ethylene vinyl acetate, or other polymer type. In instances in which the second region 50 includes a polyurethane, the polyurethane can be or can include a thermoplastic polyurethane, such as one having a softening temperature of greater than about 200⁰F, e.g., between about 21O⁰F and about 275°F, or between about 225°F and 295°F.

[0032] In some instances, the first layer 40 can have a thickness Tl of less than about 0.200 inch (5 mm), such as between about 0.010 inch (0.25 mm) and about 0.190 inch (4.8 mm), and the second layer 42 can have a thickness T2 of less than about 0.200 inch (5 mm), such as between about 0.010 inch (0.25 mm) and 0.190 inch (4.8 mm) (see FIG. 2A). When present, the third layer 54 can have a thickness T3 of less than about 0.080 inch (2 mm), such as between about 0.010 inch (0.25 mm) and about 0.078 inch (1.98 mm) (see FIG. 2A). [0033] Many different materials can be utilized for the construction of the layers 40, 42, 54. For example, any layer 40, 42, 54 can include a knit material, a woven material (e.g., a twill material or canvas material), a non-woven material, leather, coated fabrics, and/or stitching, or composite combination thereof. [0034] One general method of making the shoe upper assembly 20 of shoe 10 will now be described. A first sheet material 40 is selected having a first 30% modulus and a second sheet material 42 is selected such that the second sheet material has a second 30% modulus lower than the first 30% modulus. At least one stretch control region 36 (e.g., non-stretch zone) is created by applying a third material 51 , such as a polyurethane, a relatively non-stretchable fabric (e.g., a woven nylon) or even stitching or stitched fabric, having a third 30% modulus higher than the first and the second 30% modulus to the second sheet material 42 to form a substantially non- stretchable region 50 in and/or on the second sheet material 42, thereby providing a composite sheet material. In some cases, the first and/or second sheet materials 40, 42 having stretch characteristics (e.g., one or two dimensional stretching) and the at least one stretch control region 36 reduces or eliminates the stretching ability of the second sheet material 42 along one or more directions (e.g., longitudinal and transverse with respect to the article of footwear). [0035] In some implementations, the second sheet material 42 is die-cut to a desired pattern for the upper assembly 20 and then the third material 51 (e.g., polyurethane film) of a desired shape and pattern is applied to the second sheet material 42. In the case of using a polyurethane film as the third material 51 , a release sheet is placed under the second sheet 42 and over the third material 51. The assembly is then placed in a heat press and heated until the polyurethane impregnates the second sheet material 42 in the selected locations or regions 50. After cooling, non-stretch zones 50 are provided corresponding to locations on the second sheet where the polyurethane film was deposited. The second sheet 42 with the non-stretch zones 50 can be stitched and/or bonded to other layers to form the shoe upper assembly 20.

[0036] Referring now to FIG. 3, in another implementation, a shoe 60 includes a shoe upper assembly 64 connected to and extending from the shoe lower assembly 12. The upper assembly 64 that includes a toe box region 61, e.g., formed of canvas impregnated with rubber, a first stretch zone 63, a second stretch zone 65 and a restricted stretch zone 67. The first and second stretch zones 63, 65 may be generally located in the vamp area of the shoe, with the restricted stretch zone 67 locates substantially between the first and second stretch zones 63, 65, forward of a lacing region 62 of the shoe 60, and heelward of the toe box region 61. [0037] Referring to FIG. 3A, the shoe upper assembly 64 includes a first layer

70 and a second layer 72 coextensive with the first layer 70. The second layer 72 defines a plurality of slits 76 therein to provide at least one stretch control region 63, 65 (FIG. 3). In this instance, the slits 76 may or may not be visible to a viewer looking at the exterior of the shoe 60. Such a construction can provide biomechanically correct levels of stretch, providing maximum comfort to the wearer. Optionally, as in the implementation shown in FIG. 3A, the upper may include a third layer 80, such as a foot side or liner layer, with the second layer 72 interposed between the first and third layers 70, 80. [0038] In some implementations, the shoe 60 defines a longitudinal axis 69.

In such implementations, the slits 76 are arranged to run substantially parallel to the longitudinal axis 69 of the shoe 60. Referring particularly to FIG. 3, in some implementations, the slits 76 have a length L of between about 2 mm (0.079 inch) and about 30 mm (1.181 inch), e.g., between about 5 mm (0.197 inch) and about 25 mm (0.984 inch). For example, a lateral spacing Si between adjacent slits 76 can be between about 2 mm (0.079 inch) and about 40 mm (1.575 inch), and preferably between about 5 mm (0.197 inch) and about 35 mm (1.378 inch), and a longitudinal spacing S₂ between the slits 76 can be between about 2 mm (0.079 inch) and about 30 mm (1.181 inch), and preferably between about 5 mm (0.197 inch) and about 25 mm (0.984 inch).

[0039] In some instances, the first layer 70 includes a first material having a first 30% modulus and the second layer 72 includes a second material having a second 30% modulus higher than the first 30% modulus. [0040] One general method of making the shoe upper assembly 64 of shoe 60 will now be described. A first sheet material 70 is selected having a selected first 30% modulus. A second sheet material 72 is selected having a selected second 30% modulus higher than the first 30% modulus. Slits 76 are formed through the second sheet material 72 to provide at least one stretch control region 63, 65 of the second sheet material 72. In some implementations, the slits 76 are arranged to run substantially parallel to the longitudinal axis 69 defined by the shoe 60. However, other configurations are possible, such as arranging the slits 76 at other angles (e.g., acute or otherwise, and uniform or random) with respect to the longitudinal axis 69. The at least one stretch control region 63, 65 may be stretchable along a direction perpendicular to the slits 76. In some cases, the first and/or second sheet materials 70, 72 having stretch characteristics (e.g., one or two dimensional stretching) and the slits 76 accentuate the stretch characteristics of the second sheet material 72 along a direction perpendicular to the slits 76. The method may include selecting a third sheet material 80 and arranging the second sheet material 72 between the first sheet material 70 and the third sheet material 80, with the first, second, and third sheet materials 70, 72, 80 being coextensive with each other.

[0041 ] A number of implementations have been described. Nevertheless, it will be understood that various modifications may be made without departing from the spirit and scope of the disclosure.

[0042] For example, while implementations have been described in which the second region 50 includes material of the first region 44, 44' (e.g., a composite material), in some implementations, the second region 50 is or includes a "patch" of different material, e.g., sewn and/or bonded onto a material. The second region 50 can even be formed by applying an arrangement of stitching to a sheet material to make the region less stretchable.

[0043] Some implementations may include a second layer 42, 72 that uses combinations of stretch and non-stretch materials that are stitched or welded together. Some implementations may include first, second and/or third layers 40, 42, 54, 70, 72, 80 which include combinations of stretch and non-stretch materials. In addition, some implementations may include having areas (e.g., lateral vamp areas) of predetermined stretch and other areas (e.g., toeward of lacing region) without predetermined stretch [0044] While implementations have been shown in which slits 76 are not visible to a viewer looking at the exterior of the shoe, in other implementations, the slits 76 may be visible to convey stretch zones to a consumer. Some implementations may use slits 76 that are not parallel to the longitudinal axis 69 of the shoe 60; and some implementations may use slits 76 of varying lengths and spacing. Furthermore, some implementations use a non-stretch interlayer 51 with cut-outs of different shapes other than a slit 76, e.g., oval, rectangular, etc. [0045] In some implementations, the stretch control regions 44, 44', 50, 63,

65, 67 may be located in various locations of the shoe 10, such as in or on the lateral and/or medial sides of the lacing region 21, 62 and/or toeward of the lacing region 21 , 62 (such as the toe box region or an entire toeward portion). [0046] While implementations have been described that include stretch interlayer stretch control alone, in some implementations, the inner layer stretch construction is used in combination with slits to achieve a desired degree of stretch. Accordingly, other implementations are within the scope of the following claims.

Claims

WHAT IS CLAIMED IS:

1. An article of footwear ( 10) comprising: a lower assembly (12) comprising a sole assembly (14); and an upper assembly (20) attached to the sole assembly ( 12), the upper and lower assemblies (12, 20) together defining a void (22) for receiving a foot, the upper assembly (20) comprising: a first layer (40)comprising a first material having a first 30% modulus; and a second layer (42) coextensive with the first layer (40), the second layer (42) comprising at least one first region (44, 44') and at least one second region (50); the at least one first region (44, 44') comprising a second material having a second 30% modulus lower than the first 30% modulus; and the at least one second region (50) comprising a third material having a third 30% modulus higher than both the first 30% modulus and the second 30% modulus.

2. The article of footwear (10) of claim 1, wherein the second 30% modulus is less than about 0.3 kg/cm, and particularly between about 0.04 kg/cm and about 0.25 kg/cm.

3. An article of footwear (10) comprising: a lower assembly (12) comprising a sole assembly (14); and an upper assembly (20) attached to the sole assembly (12), the upper and lower assemblies (12, 20) together defining a void (22) for receiving a foot, the upper assembly (20) comprising: a first layer (40) comprising a first material having a first 30% modulus; and a second layer (42) coextensive with the first layer (40), the second layer (42) comprising at least one first region (44, 44') and at least one second region (50); the at least one first region (44, 44') comprising a second material having a second 30% modulus higher than the first 30% modulus; and the at least one second region (50) comprising a third material having a third 30% modulus higher than both the first 30% modulus and the second 30% modulus.

4. The article of footwear (10) of claim 3, wherein the second 30% modulus is greater than 2 kg/cm.

5. The article of footwear (10) of any of the preceding claims, wherein the first 30% modulus is less than 2 kg/cm, and particularly between about 0.2 kg/cm and about 1.9 kg/cm.

6. The article of footwear (10) of any of the preceding claims, wherein the first layer (40) has a thickness of less than about 0.200 inch (5 mm) and the second layer (42) has a thickness of less than about 0.200 inch (5 mm).

7. The article of footwear (10) of any of the preceding claims, further comprising a third layer (54) comprising a fourth material having a fourth 30% modulus less than the first 30% modulus.

8. The article of footwear (10) of claim 7, wherein the second layer (42) is interposed between the first and third layers (40, 54), the first, second, and third layers (40, 42, 54) being coextensive with each other.

9. The article of footwear (10) of any of claims 7-8, wherein the third layer (54) has a thickness of less than about 0.080 inch (2 mm).

10. The article of footwear ( 10) of any of the preceding claims, wherein the third 30% modulus is greater than about 2.0 kg/cm.

11. An article of footwear (60) comprising: a lower assembly (12) comprising a sole assembly (14); and an upper assembly (64) attached the sole assembly (12), the upper and lower assemblies (12, 64) together defining a void (22) for receiving a foot, the upper assembly (64) comprising: a first layer (70); and a second layer (72) coextensive with the first layer (70), the second layer (72) defining a plurality of slits (76) in at least one stretch control region (63, 65) defined by the second layer (72).

12. The article of footwear (60) of claim 1 1 , wherein the article of footwear (60) defines a longitudinal axis (69), and the slits (76) are arranged to run substantially parallel to the longitudinal axis (69).

13. The article of footwear (60) of claim 1 1 or claim 12, wherein the first layer (70) comprises a first material having a first 30% modulus and the second layer (72) comprises a second material having a second 30% modulus higher than the first 30% modulus.

14. The article of footwear (60) of any of claims 1 1-13, further comprising a third layer (80) having a third 30% modulus lower than both the first 30% modulus and the second 30% modulus.

15. A method of making an upper (20) of an article of footwear ( 10), the method comprising: selecting a first sheet material (40) having a first 30% modulus; selecting a second sheet material (42) having a second 30% modulus lower than the first 30% modulus; applying a stretch control material (51) having a third 30% modulus higher than the first 30% modulus and the second 30% modulus to the second sheet material (42) to form at least one stretch control region (50) of the second sheet material (42); and arranging the first sheet material (40) and the second sheet material (42) to be coextensive with each other.

16. A method of making an upper (20) of an article of footwear ( 10), the method comprising: selecting a first sheet material (40) having a first 30% modulus; selecting a second sheet material (42) having a second 30% modulus higher than the first 30% modulus; applying a stretch control material (51) having a third 30% modulus higher than the first 30% modulus and the second 30% modulus to the second sheet material (42) to form at least one stretch control region (50) of the second sheet material (42); and arranging the first sheet material (40) and the second sheet material (42) to be coextensive with each other.

17. The method of claim 15 or claim 16, further comprising selecting a third sheet material (54) and arranging the second sheet material (42) between the first sheet material (40) and the third sheet material (54), the first, second, and third sheet materials (40, 42, 54) being coextensive with each other.

18. A method of making an upper (64) of an article of footwear (60), the method comprising: selecting a first sheet material (70) having a first 30% modulus; selecting a second sheet material (72) having a second 30% modulus higher than the first 30% modulus; and forming slits (76) through the second sheet material (72) to provide at least one stretch control region (63, 65).

19. The method of claim 18, further comprising arranging the first sheet material (70) and the second sheet material (72) to be coextensive with each other.

20. The method of claims 18 or claim 19, further comprising selecting a third sheet material (80) and arranging the second sheet material (72) between the first sheet material (70) and the third sheet material (80), the first, second, and third sheet materials (70, 72, 80) being coextensive with each other.