WO2017123618A1

WO2017123618A1 - Conformable and pressure-spreading footbeds, methods of manufacture thereof, and articles containing the footbed

Info

Publication number: WO2017123618A1
Application number: PCT/US2017/012996
Authority: WO
Inventors: Dave Sherman; Nicole Ouellette PERRY; Brian J. Culley; Eric BEAUDRY
Original assignee: Rogers Corporation
Priority date: 2016-01-15
Filing date: 2017-01-11
Publication date: 2017-07-20
Also published as: CN108495567A; DE112017000398T5; GB201810576D0; GB2561758A; JP2019501717A; US20170202300A1; KR20180101400A

Abstract

A footbed for use in an article of footwear, the footbed comprising a conforming layer having an initial, substantially uniform thickness of 3 to 9 millimeters, and comprising a foam that permanently conforms to a shape of a foot after wear; and a pressure-spreading layer disposed on the conforming layer, having a thickness of 2 to 4 millimeters, and comprising a resilient foam.

Description

CONFORMABLE AND PRESSURE- SPREADING FOOTBEDS, METHODS OF MANUFACTURE THEREOF, AND ARTICLES CONTAINING THE FOOTBED

BACKGROUND

[0001] This disclosure relates generally to a footbed for use in an article of footwear. More particularly, the present disclosure relates to a footbed that conforms to and relieves pressure on a foot.

[0002] Items of footwear, for example shoes, boots, slippers, or sandals generally include an upper, which is in contact in with the top of a foot, connected to a sole, which is in contact with the bottom of the foot. The sole generally includes an outermost sole (an outsole) and can further include a midsole disposed on or attached to the outsole, and an inner sole disposed on or attached to the midsole. The term "footbed" refers to the layer of the sole in closest contact with the foot. Thus, when an inner sole is in contact with the foot when the footwear is worn, it can be referred to generally as a footbed. Alternatively, any number of sole layers can be present between the outsole and the footbed.

[0003] Several factors contribute to a comfortable shoe. For example, footwear feels comfortable to a wearer's foot if the sole conforms to the shape of the foot and avoids or relieves pressure on the foot. A large number of footbeds have been proposed that conform to the shape of the foot, or that relieve pressure on the foot. However, there nonetheless remains a need in the art for a footbed that both conforms to the shape of a foot and effectively relieves pressure. It would be a further advantage if the footbed could be readily customized to individual foot shapes, and a still further advantage if the footbed could be easily manufactured at low cost.

BRIEF SUMMARY

[0004] Described herein is a footbed for use in an article of footwear, the footbed comprising a conforming layer having an initial, substantially uniform thickness of 3 to 9 millimeters, and comprising a foam that permanently conforms to a shape of a foot after wear; and a pressure-spreading layer disposed on the conforming layer, having a thickness of 2 to 4 millimeters, and comprising a resilient foam.

[0005] Additionally described herein is a method for the manufacture of the above- described footbed, the method comprising laminating the conforming layer and the pressure- spreading layer to provide the footbed. [0006] Additionally described herein is a method for the manufacture of the above- described footbed, the method comprising forming the pressure relieving layer on the conforming layer, or forming the conforming layer on the pressure relieving layer to provide the footbed.

[0007] Further described is an article of footwear, the article comprising an outsole, an upper attached to the outsole, and the conforming layer of the above-described footbed disposed on the outsole.

[0008] The above described and other features are exemplified by the following Figures and Detailed Description.

BRIEF DESCRIPTION OF THE DRAWINGS

[0009] In the following Figures, which are exemplary, like elements are numbered alike.

[0010] FIG. 1 is a schematic cross-sectional view of a footbed in accordance with an exemplary embodiment.

[0011] FIG. 2 is a schematic, cross-sectional view of a footbed before and after compression by a wearer, according to an embodiment.

DETAILED DESCRIPTION

[0012] The present disclosure relates to a footbed for use in an article of footwear. The footbed includes two different layers of foam, a conforming layer and a foam pressure- spreading layer, each having a specified thickness. The conforming layer permanently shapes itself to the foot with ordinary wear. The pressure-spreading layer does not permanently take a shape, and thus continues to provide cushioning that distributes and relieves pressure on the foot during ordinary wear. This combination provides the wearer with a footbed that is customized to the shape of their foot, and further provides pressure spreading within that shape. The thickness of the pressure-spreading layer is sufficient to fill a conformed depression in the conforming layer. The combination of a conforming layer and a pressure- spreading layer of these thicknesses provides comfort to a foot by both adapting to the shape of a foot and relieving pressure on the foot during wear. Because the conforming layer conforms during ordinary use by the wearer, it is readily customized to each individual wearer. This feature also provides low-cost and efficient manufacture of the footbed.

[0013] FIG. 1 shows an example of a footbed 10, which has a conforming layer 11, a pressure-spreading layer 15, and an optional top cover fabric 21. [0014] The conforming layer 11 has first and second major surfaces 12 and 13 and a perimeter 14. The major surface 32 of conforming layer 11 is disposed on an outsole of a footwear article. As used herein, "disposed on" includes directly on, as well as adjacent with one or more intervening layers. Thus, the major surface 32 of conforming layer 11 can be disposed directly on or adjacent an outsole of a footwear article. The conforming layer (and thus the footbed) can be permanently attached to the outsole (or a sole adjacent the outsole, e.g., a midsole), or removable.

[0015] As described above, the purpose of the conforming layer is to provide comfort to the wearer by conforming the foot of the wearer and providing shock absorption. The conforming layer 11 accordingly comprises a foam that conforms to the wearer's foot upon and after wear, and that provides shock absorption. As used herein, "wear" means actual use of the footwear, i.e., standing or locomotion by the user. In particular, the conforming shape of the conforming layer is retained after a period of ordinary wear, becoming essentially permanent. Thus, the conforming layer is a foam having a high compression set at temperatures and pressures encountered during ordinary use of the footbed, for example 0 to 120°F (-18 to 49 °C), or 21 to 100°F (-6 to 38 °C), or 21 to 75°F (-6 to 24 °C). Preferably the conforming layer begins to conform and retain some shape shortly after wear begins, for example after 60 minutes of wear. In some embodiments, conformation begins between 10 and 120 minutes of wear. The conformable layer is substantially completely conformed, or completely conformed after 3 hours of wear, or after 6 hours of wear, for example after 3 to 12 hours of wear. The conformable layer can take a compression set of 25 to 50%, preferably 35 to 50%. Before wear, the conforming layer can have an Asker C hardness of 5 to 20, preferably 10 to 20. Again before wear, the foam can have a density of 8 to 240 kg/m³, preferably 20 to 150 kg/m³.

[0016] Foams that meet the foregoing properties include an ethylene-vinyl acetate (EVA) foam, polyethylene (PE) foam, polyethylene-polypropylene blend foam, polystyrene foam, neoprene foam, chloroprene foam, polyurethane foam, or a combination comprising at least one of the foregoing. The foam can be an air-permeable, open-cell or closed-cell foam, including a combination of open and closed cells. Exemplary EVA compositions can include copolymers can have a vinyl acetate content of 5 to 25 weight percent, or 6 to 20 weight percent based on the total weight of the EVA copolymer. In some embodiments, the copolymer is blended with an ethylene homopolymer, such as a low density polyethylene (LDPE), or with an ethylene-alpha-olefin copolymer. Exemplary EVA foams can be obtained from Sekisui Chemical Company under the VOLARA trademark. [0017] Referring again to FIG. 1, the pressure-spreading layer 15 has first and second major surfaces 16 and 17 and a perimeter 18. The first major surface 16 is disposed on or adjacent to the second major surface 13 of the conforming layer 11, such that second major surface 17 is closer to the foot during use. The pressure-spreading layer 15 is firmly or permanently attached to the conforming layer 11, for example by an adhesive. The pressure- spreading layer 15 can be present only on a portion of the conforming layer 11, for example on a heel region or at the ball of the foot. The pressure-spreading layer 15 generally has approximately the same length as the conforming layer 11 from the heel end 19 to the toe end 20 to provide maximum comfort to the wearer and ease of manufacture. The perimeter 18 of the pressure-spreading layer 15 can be generally shaped to correspond to the perimeter 14 of the conforming layer 11, or can be slightly larger in size.

[0018] The function of the pressure-spreading layer is to provide comfort to the foot by permanently spreading pressure across the foot during ordinary wear. Thus, in contrast to the conforming layer 11, the foam of the pressure-spreading layer is resilient, in that it does not permanently conform to the foot during ordinary wear. The foam is thus selected to have a lower compression set under the conditions or ordinary wear as described above. For example, the foam can have a compression set of 0 to 20%, preferably 1 to 10%, for example as measured at 25°C, or at 30 °C, or at 37 °C. Preferably, the low compression set is maintained for longer periods of time,. E.g. for at least one month, at least three months, at least six months, or at least 12 months. In some embodiments the foam can maintain a compression set of 0 to 20%, preferably 1 to 10%, over a period of 3 to 12 months, or 6 to 24 months after ordinary wear. To provide an optimal balance of pressure spreading and softness, the pressure-spreading layer can have an Asker C hardness of 10 to 40, preferably 25 to 30. The foam can have a density of 8 to 400 kg/m³, preferably 120 to 320 kg/m³.

[0019] Foams that meet the foregoing properties include polyurethane foam, polypropylene foam, or a combination comprising at least one of the foregoing. The pressure-spreading layer can also comprise other polymers such as polyethylene,

polypropylene, polyurethane, or a combination comprising at least one of the foregoing. The pressure-spreading layer can be, for example, an air-permeable, open cell, polyurethane foam, preferably a microcellular polyurethane foam. Polyurethane foams can be formed from reactive compositions comprising an organic isocyanate component reactive with an active hydrogen-containing component(s), a surfactant, and a catalyst. Exemplary polyurethane foams include the foams available under the PORON trademark from Rogers Corporation, Rogers, CT. [0020] As mentioned above, the thickness of each of the conforming layer and the pressure-spreading layer is selected to be within specific ranges that provide additional comfort to the wearer. The conforming layer has an initial (before wear), substantially uniform thickness of 3 to 9 millimeters (mm), preferably 4 to 8 mm, or 5 to 7 mm, more preferably 6 mm. As used herein, "substantially uniform thickness" means that the conforming layer can have a thickness that is uniform within plus/minus 20% relative to 100% uniformity.

[0021] The pressure-spreading layer has a thickness of 2 to 4 mm, or 2.5 to 3.5 mm, preferably 3 mm. Preferably, the thickness the conforming layer is selected to accommodate and conform to the features of an individual's foot, such as arch height, heel cupping, and forefoot conformance. The thickness of the pressure spreading layer is such to maximize pressure spreading and comfort within the space allowed for in the shoe manufacture. These features are illustrated in FIG. 2.

[0022] FIG. 2 shows an exemplary embodiment of a footbed wherein pressure- spreading layer 15 is disposed on conforming layer 11. Before use, pressure-spreading layer 15 of the footbed has a thickness A and conforming layer 11 has a thickness B. With use, pressure from the foot depresses both layers such that pressure-spreading layer 15 assumes thickness C and conforming layer 1 1 has thickness D. Thickness C is equal to or less than thickness A, preferably less. Thickness D is equal to or less than thickness B, preferably less. Pressure from the foot generally results in depression E in the heel section and depression G in the forefoot section of the foot. At the same time the footbed also adapts to the midfoot section of the foot to form elevation F. Substantially conforming to the shape of the foot, i.e. heel, arch, ball, and toes, provides increased comfort for the wearer.

[0023] The footbed can further comprise other layers to enhance the comfort for the wearer or to provide efficient manufacture. For example, as shown in FIG. 1, an optional top fabric layer 21 has first and second major surfaces 22 and 23. The first major surface is disposed directly on or adjacent to the second major surface 17 of the pressure-spreading layer 15. The second major surface 23 is nearer the foot during use. Adhesive layers can be present (not shown). For example, in some embodiments the fabric layer 21 is adhered to the pressure-spreading layer 15 by an adhesive layer. The adhesive layer can also be disposed between the pressure relieving and the conforming layer. In some embodiments, the foot bed can be adhered to a midsole (for example by sewing, stapling, or adhesion), which can then be inserted into a shoe, or affixed to an outsole. [0024] Optionally, the top surface of the footbed (e.g., 21 or 17) or the bottom surface (e.g., 12) can be printed or embossed to include a decorative pattern, or with a brand logo, or with "cut-to-size" markings.

[0025] The footbeds can be manufactured by methods known in the art. For example, the compressive and the pressure-spreading foam layers can be separately manufactured or purchased, for example in the form of sheets. The sheets can then be adhered, and then cut to the desired size. Adhesion can be by use of an adhesive layer, sewing, stapling, or other method. The adhesive can be applied in the form of "dabs" at select locations or across the whole surface or portions thereof. The adhesive can be sprayed, brushed, roll coated, printed, or applied continuously or discontinuously by any other suitable method. Cutting can be, for example die cutting. It is also possible to cut each layer into the desired shape and then adhere the cut layers. Alternatively, the footbeds can be manufactured by forming one layer on the other layer, with or without an intermediate adhesive layer. If no adhesive is present, the layers can be stitched, stapled, or otherwise affixed. The dual-layer foam can then be cut to the desired size.

[0026] Methods for the manufacture of foams are generally known. The foams can be physically or chemically blown, mechanically frothed, or both. Physical blowing agents include carbon dioxide, ethane, propane, n-butane, isobutane, pentane, hexane, butadiene, acetone, methylene chloride, any of the chlorofluorocarbons, hydrochlorofluorocarbons, or hydrofluorocarbons, as well as combinations comprising at least one of the foregoing.

Chemical blowing agents include, for example, water (for polyurethanes), and chemical compounds that decompose with a high gas yield under specified conditions, for example within a narrow temperature range. Desirably, the decomposition products do not effloresce or have a discoloring effect on the foam product. Exemplary chemical blowing agents include azoisobutyronitrile, azodicarbonamide (i.e. azo-bis-formamide) and barium azodicarboxylate; substituted hydrazines (e.g., diphenylsulfone-3,3'-disulfohydrazide, 4,4'- hydroxy-bis-(benzenesulfohydrazide), trihydrazinotriazine, and aryl-bis-(sulfohydrazide)); semicarbazides (e.g., p-tolylene sulfonyl semicarbazide an d4,4'-hydroxy-bis- (benzenesulfonyl semicarbazide)); triazoles (e.g., 5-morpholyl-l,2,3,4- thiatriazole); N- nitroso compounds (e.g., Ν,Ν'- dinitrosopentamethylene tetramine and N,N-dimethyl-N,N'- dinitrosophthalmide); benzoxazines (e.g., isatoic anhydride); as well as combinations comprising at least one of the foregoing, such as, sodium carbonate/citric acid mixtures.

[0027] Optional additives can be added to foam compositions to achieve a desired property, such as color, antibacterial properties, deodorizing properties, and the like. For example, additives such as fillers (alumina trihydrate, silica, talc, calcium carbonate, clay, and the like), nucleating agents (e.g., zinc oxide, zirconium oxide, silica, talc, or the like), an aging modifier (e.g., a fatty acid ester, a fatty acid amide, a hydroxyl amide, or the like)dyes, pigments (for example titanium dioxide and iron oxide), antioxidants, antiozonants, flame retardants, heat stabilizers, fragrances, anti-bacterial agents, odor-masking agents, or the like, as well as combinations comprising at least one of the foregoing additives, can also be used.

[0028] The foam compositions can be extruded or cast to form a layer, for example extruded or cast onto a carrier or the other foam layer. A second carrier can be placed on the extruded or cast composition on a side opposite the first carrier to control the thickness of the foam. The foam can be spread to a layer of desired thickness, e.g., by a doctoring blade or other spreading device. Alternatively, placement of the second carrier can be used to spread the foam and adjust the layer to the desired thickness. The selection of materials for carriers will depend on factors such as the desired degree of support and flexibility, the desired degree of releasability from the cured foam, cost, aesthetics, and the like considerations. Paper, thin sheets of metal such as stainless steel, or polymer films such as polyethylene terephthalate, silicone, or the like, can be used. The material can be coated with a release coating. In some embodiments, the carrier can be embossed to provide a pattern to a surface of the foam, or coated with a material intended to be transferred to a surface of the foam, for example an adhesive. A fibrous web or other filler material can be disposed on the surface of the carrier, and thereby become ultimately incorporated into the cured foam. In some embodiments, the foam can cure to one of the carriers, for example the cloth layer 21. Thus, one carrier can form part of the final product instead of being separated from the foam. Alternatively, or in addition, a conveyor belt can be used as the bottom carrier.

[0029] In particular, the EVA foams can be formed from EVA copolymers have a melt index of greater than 1 gram/ 10 minutes; more preferably greater than 1.5 g/ 10 min, using a physical or chemical blowing agent. The blowing agent can be mixed with the EVA composition in any desired amount to achieve a desired degree of expansion in the resultant foam. Generally, the blowing agent may be added to the EVA composition in an amount of about 0.5 to 80 parts by weight, based on 100 parts by weight of the polymer. Preferably, the blowing agent is present at an amount of 1 to 30, more preferably 3 to 15, parts per 100 parts by weight of the polymer.

[0030] EVA foams are generally made by extrusion. In such a process, the EVA and any additional polymers, e.g., LDPE, are added to an extruder, preferably in the form of pellets. Any conventional type of extruder may be used, e.g., single screw, double screw, and/or tandem extruders. In the extruder, the resin pellets are melted and mixed. A blowing agent can be added to the melted polymer via one or more injection ports in the extruder. Any additives that are used may be added to the melted polymer in the extruder and/or may be added with the resin pellets. The extruder pushes the entire melt mixture (melted polymer, blowing agent, and any additives) through a die at the end of the extruder and into a region of reduced temperature and pressure (relative to the temperature and pressure within the extruder). Typically, the region of reduced temperature and pressure is the ambient atmosphere. The sudden reduction in pressure causes the blowing agent to nucleate and expand into a plurality of cells that solidify upon cooling of the polymer mass (due to the reduction in temperature), thereby trapping the blowing agent within the cells.

[0031] The polyurethane foams can be made by casting a mechanically frothed composition. In particular, the reactive precursors of the polyurethane can be mixed and mechanically, frothed, then cast to form a layer, and cured.

[0032] Any one or more of the layers of the footbed can be treated with an

antimicrobial agent to reduce odor-causing microorganisms. Examples of such antimicrobial agents include: silane functionalized quaternary amines such as Microbe Shield™ available from AEGIS Environments; colloidal silver solutions such as Silpure™ available from Thompson Research Associates, Canada, silver chelated polymer solutions such as

SilvaDur™ available from Rohm & Haas; biguanides such as polyhexamethylene biguanide sold under the trade names Vantocil™ and Cosmocil™ available from Arch Chemicals; and antimicrobial additives available from Microban under the Microban trademark. Treatment can comprises incorporating the antimicrobial agent into one or more materials used to manufacture the footbed, or by a post-treatment process, for example spraying or cutting.

[0033] The entire construction of the footbed can be permeable to air due to the choice of materials as well as the molding and assembly processes. The air permeability of the total footbed can be is less than 60 seconds, more typically less than 20 seconds, for 100 cm³ of air to pass through the sample under ASTM D-726-58.

[0034] The footbeds are used in articles of footwear. The footbeds are suitable for any type of footwear, including shoes, boots, slippers, sandals, and athletic shoes. Such articles include an outsole, an upper attached to the outsole, and the footbed as described herein. The footwear article can also include other layers, for example a midsole, an insole, or a combination comprising at least one of the foregoing. If present, the midsole can be disposed between the outsole and the conforming layer. The footbed can be permanently affixed to the footwear, for example by an adhesive, sewing, or stapling. This embodiment is preferred for sandals. Alternatively the footbed can be present as a removable insert.

[0035] The invention is further illustrated by the following embodiments.

[0036] Embodiment 1 : A footbed for use in an article of footwear, the footbed comprising: a conforming layer having an initial, substantially uniform thickness of 3 to 9 millimeters, and comprising a foam that permanently conforms to a shape of a foot after wear; and a pressure-spreading layer disposed on the conforming layer, having a thickness of 2 to 4 millimeters, and comprising a resilient foam.

[0037] Embodiment 2: The footbed of embodiment 1, wherein the conforming layer has a thickness of 4 to 8 millimeter, preferably 5 to 7 millimeters.

[0038] Embodiment 3 : The footbed of any one or more of embodiments 1 to 2, wherein the pressure-spreading layer has a thickness less than the thickness of the

conforming layer.

[0039] Embodiment 4: The footbed of any one or more of embodiments 1 to 3, wherein the pressure-spreading layer has a thickness of 2.5 to 3.5 millimeter.

[0040] Embodiment 5 : The footbed of any one or more of embodiments 1 to 4, wherein the conforming layer comprises ethylene-vinyl acetate, a polyethylene, polyethylene- polypropylene blend, polystyrene, neoprene, chloroprene, polyurethane, or a combination comprising at least one of the foregoing, preferably ethylene-vinyl acetate.

[0041] Embodiment 6: The footbed of any one or more of embodiments 1 to 5, wherein the pressure-spreading layer comprises polyurethane, polypropylene or a

combination comprising at least one of the foregoing, preferably a microcellular polyurethane foam.

[0042] Embodiment 7: The footbed of any one or more of embodiments 1 to 6, wherein the pressure-spreading layer reduces a pressure point on a foot of a wearer.

[0043] Embodiment 8: The footbed of any one or more of embodiments 1 to 7, wherein the conforming layer has an Asker C hardness of 5 to 20, preferably 10 to 20, before use of the footbed by a wearer.

[0044] Embodiment 9: The footbed of any one or more of embodiments 1 to 8, wherein the pressure-spreading layer has an Asker C hardness of 10 to 40, preferably 25 to 30, before use of the footbed by a wearer.

[0045] Embodiment 10: The footbed of any one or more of embodiments 1 to 9, wherein the pressure-spreading layer has a compression set of 0 to 20%, preferably 1 to 10%, at 25°C before use of the footbed by a wearer. [0046] Embodiment 11 : The footbed of any one or more of embodiments 1 to 10, wherein the pressure-spreading layer extends substantially the entire length of the conforming layer.

[0047] Embodiment 12: The footbed of any one or more of embodiments 1 to 1 1 further comprising a fabric layer disposed on a side of the pressure-spreading layer opposite the conforming layer.

[0048] Embodiment 13 : The footbed of any one or more of embodiments 1 to 12 further comprising an adhesive layer disposed between the pressure relieving and the conforming layer, or between the fabric layer and the pressure-spreading layer.

[0049] Embodiment 14: A method for the manufacture of the footbed of any one or more of embodiments 1 to 13, comprising laminating the conforming layer and the pressure- spreading layer to provide the footbed.

[0050] Embodiment 15: A method for the manufacture of the footbed of any one or more of embodiments 1 to 13, comprising forming the pressure relieving layer on the conforming layer or forming the conforming layer on the pressure relieving layer to provide the footbed.

[0051] Embodiment 16: A footbed made by the method of embodiment 14 or embodiment 15.

[0052] Embodiment 17: An article of footwear comprising an outsole, an upper attached to the outsole, and the conforming layer of the footbed of any one or more of embodiments 1 to 16 disposed on the outsole.

[0053] Embodiment 18: The article of embodiment 17 further comprising a midsole, an insole, or a combination comprising at least one of the foregoing.

[0054] In general, the articles and methods described here can alternatively comprise, consist of, or consist essentially of, any components or steps herein disclosed. The articles and methods can additionally, or alternatively, be manufactured or conducted so as to be devoid, or substantially free, of any ingredients, steps, or components not necessary to the achievement of the function or objectives of the present claims.

[0055] The singular forms "a," "an," and "the" include plural referents unless the context clearly dictates otherwise. "Or" means "and/or." Unless defined otherwise, technical and scientific terms used herein have the same meaning as is commonly understood by one of skill in the art to which this invention belongs. A "combination" is inclusive of blends, mixtures, alloys, reaction products, and the like. The values described herein are inclusive of an acceptable error range for the particular value as determined by one of ordinary skill in the art, which will depend in part on how the value is measured or determined, i.e., the limitations of the measurement system. The endpoints of all ranges directed to the same component or property are inclusive and independently combinable (e.g., ranges of "less than or equal to 25 wt%, or 5 wt% to 20 wt%," is inclusive of the endpoints and all intermediate values of the ranges of "5 wt% to 25 wt%," etc.). Disclosure of a narrower range or more specific group in addition to a broader range is not a disclaimer of the broader range or larger group.

[0056] All cited patents, patent applications, and other references are incorporated herein by reference in their entirety. However, if a term in the present application contradicts or conflicts with a term in the incorporated reference, the term from the present application takes precedence over the conflicting term from the incorporated reference.

[0057] While the disclosed subject matter is described herein in terms of some embodiments and representative examples, those skilled in the art will recognize that various modifications and improvements can be made to the disclosed subject matter without departing from the scope thereof. Additional features known in the art likewise can be incorporated. Moreover, although individual features of some embodiments of the disclosed subject matter can be discussed herein and not in other embodiments, it should be apparent that individual features of some embodiments can be combined with one or more features of another embodiment or features from a plurality of embodiments.

Claims

1. A footbed for use in an article of footwear, the footbed comprising:

a conforming layer having an initial, substantially uniform thickness of 3 to 9 millimeters, and comprising a foam that permanently conforms to a shape of a foot after wear; and

a pressure-spreading layer disposed on the conforming layer, having a thickness of 2 to 4 millimeters, and comprising a resilient foam.

2. The footbed of claim 1, wherein the conforming layer has a thickness of 4 to 8 millimeters, preferably 5 to 7 millimeter.

3. The footbed of any one or more of claims 1 to 2, wherein the pressure- spreading layer has a thickness less than the thickness of the conforming layer.

4. The footbed of any one or more of claims 1 to 3, wherein the pressure- spreading layer has a thickness of 2.5 to 3.5 millimeter.

5. The footbed of any one or more of claims 1 to 4, wherein the conforming layer comprises ethylene-vinyl acetate, a polyethylene, polyethylene-polypropylene blend, polystyrene, neoprene, chloroprene, polyurethane, or a combination comprising at least one of the foregoing, preferably ethylene-vinyl acetate.

6. The footbed of any one or more of claims 1 to 5, wherein the pressure- spreading layer comprises polyurethane, polypropylene or a combination comprising at least one of the foregoing, preferably a microcellular polyurethane foam.

7. The footbed of any one or more of claims 1 to 6, wherein the pressure- spreading layer reduces a pressure point on a foot of a wearer.

8. The footbed of any one or more of claims 1 to 7, wherein the conforming layer has an Asker C hardness of 5 to 20, preferably 10 to 20, before use of the footbed by a wearer.

9. The footbed of any one or more of claims 1 to 8, wherein the pressure- spreading layer has an Asker C hardness of 10 to 40, preferably 25-30, before use of the footbed by a wearer.

10. The footbed of any one or more of claims 1 to 9, wherein the pressure- spreading layer has a compression set of 0 to 20%, preferably 1 to 10%, at 25°C before use of the footbed by a wearer.

11. The footbed of any one or more of claims 1 to 10, wherein the pressure- spreading layer extends substantially the entire length of the conforming layer.

12. The footbed of any one or more of claims 1 to 11 further comprising a fabric layer disposed on a side of the pressure-spreading layer opposite the conforming layer.

13. The footbed of any one or more of claims 1 to 12 further comprising an adhesive layer disposed between the pressure relieving and the conforming layer, or between the fabric layer and the pressure-spreading layer.

14. A method for the manufacture of the footbed of any one or more of claims 1 to 13, comprising laminating the conforming layer and the pressure-spreading layer.

15. A method for the manufacture of the footbed of any one or more of claims 1 to 13, comprising forming the pressure relieving layer on the conforming layer or forming the conforming layer on the pressure relieving layer to provide the footbed.

16. A footbed made by the method of claim 14 or claim 15.

17. An article of footwear comprising an outsole, an upper attached to the outsole, and the conforming layer of the footbed of any one or more of claims 1 to 16 disposed on the outsole.

18. The article of claim 17 further comprising a midsole, an insole, or a combination comprising at least one of the foregoing.