Login| Sign Up| Help| Contact|

Patent Searching and Data


Title:
FLEXIBLE PLATFORM SHOE
Document Type and Number:
WIPO Patent Application WO/2009/109833
Kind Code:
A1
Abstract:
A flexible platform shoe, having a heel portion, a midfoot portion, and a forefoot portion, the heel portion covering the heel of the foot, the midfoot portion covering the arch of the foot, the forefoot portion covering the metatarsal heads and toes of the foot, the heel portion having a substantially rigid heel, raising a user's heel at least 3.5 cm above a ground surface, the midfoot portion having a substantially rigid arch support spanning from the heel portion to the forefoot portion, the forefoot portion having a midsole disposed between an insole and an outsole, the midsole having a shape retentive resilient material that conforms along the longitudinal axis of the shoe with the flexion of the foot but resists substantial compression along the vertical axis of the midsole during use of the shoe, and the outsole being relatively less conforming to the foot than the midsole.

Inventors:
WILKENFELD, David (34 Carlotta Road, Double BaySydney, New South Wales 2029, AU)
Application Number:
IB2009/000398
Publication Date:
September 11, 2009
Filing Date:
March 03, 2009
Export Citation:
Click for automatic bibliography generation   Help
Assignee:
POINTE NOIR PTY LTD. (Suite 2, Wharf 19-21Jones Bay Wharf,Pirrama Road,Pyrmon, NSW 2009, AU)
WILKENFELD, David (34 Carlotta Road, Double BaySydney, New South Wales 2029, AU)
International Classes:
A43B13/12; A43B5/12; A43B7/28; A43B7/38; A43B9/14; A43B13/18
Domestic Patent References:
WO2005063072A1
WO2006043923A1
WO2008113197A2
Foreign References:
US20070011918A1
DE10117981A1
Download PDF:
Claims:
CURRENTLY CLAIMED INVENTIONS: 1. A flexible platform shoe, comprising: a heel portion, a midfoot portion, and a forefoot portion; the heel portion covering the heel of the foot; the midfoot portion covering the arch of the foot; the forefoot portion covering the metatarsal heads and toes of the foot; the heel portion comprising a substantially rigid heel, raising a user's heel at least 3.5 cm above a ground surface; the midfoot portion comprising a substantially rigid arch support spanning from the heel portion to the forefoot portion; and the forefoot portion comprising a midsole disposed between an insole and an outsole, the midsole comprising a shape retentive, resilient material that resiliently conforms along the longitudinal axis of the shoe with the flexion of the foot but resists substantial compression along the vertical axis of the midsole during use of the shoe, and the outsole being relatively less conforming to the foot than the midsole.

2. The shoe of claim 1 , wherein the forefoot portion raises the user's foot at least 0.5 cm above a ground surface.

3. The shoe of claim 1, wherein the forefoot portion raises the user's foot about 1 cm above a ground surface.

4. The shoe of claim 1 , wherein the midsole has a peripheral portion with a thickness of about 0.5 cm.

5. The shoe of claim 1, wherein the midsole has a central portion with a thickness of about 1.5 cm.

6. The shoe of claim 1 , wherein the midsole has a central portion with a thickness of about 2.0 cm.

7. The shoe of claim 1, wherein the midsole has a central portion with a thickness ranging between about 1.5 cm and about 2.0 cm.

8. The shoe of claim 1 , wherein the midsole comprises a foam material with an average hardness ranging between about 45 Asker C and about 95 Asker C durometer.

9. The shoe of claim 1, wherein the midsole comprises a foam material with an average hardness ranging between about 60 Asker C and about 80 Asker C durometer.

10. The shoe of claim 1, wherein the midsole comprises a foam material with an average hardness of about 70 Asker C durometer.

11. The shoe of claim 1 , wherein the midsole comprises a material comprising a shape retentive, flexible polymer.

12. The shoe of claim 1, wherein the midsole comprises an injection molded foam.

13. The shoe of claim 1, wherein the midsole comprises ethylene vinyl acetate with an average hardness ranging between about 45 Asker C and about 95 Asker C durometer.

14. The shoe of claim 1 , wherein the midsole comprises ethylene vinyl acetate with an average hardness ranging between about 60 Asker C and about 80 Asker C durometer.

15. The shoe of claim 1, wherein the midsole comprises ethylene vinyl acetate with an average hardness of about 70 Asker C durometer.

16. The shoe of claim 1, wherein the midsole is dimensioned to reside from a toe portion of the shoe to the midfoot portion of the shoe with the midsole vertical cross section thinning towards the midfoot portion of the shoe.

17. The shoe of claim 1 , wherein the width of the midsole approximately mirrors the shape and width of the overlying region of the wearer's foot.

18. The shoe of claim 1 , wherein the midsole is dimensioned to have its thickest vertical cross section in a central portion of the midsole and its thinnest vertical cross section at the toe tip of the midsole.

19. The shoe of claim 1 , wherein the heel has a height of at least 5.0 cm.

20. A flexible platform shoe, comprising: a heel portion, a midfoot portion, and a forefoot portion; the heel portion covering the heel of the foot; the midfoot portion covering the arch of the foot; the forefoot portion covering the metatarsal heads and toes of the foot; the heel portion comprising a substantially rigid heel, raising a user's heel at least 3.5 cm above a ground surface; the midfoot portion comprising a substantially rigid arch support spanning from the heel portion to the forefoot portion; the forefoot portion comprising a midsole disposed between an insole and an outsole, the insole forming the interior bottom of the shoe comprising an upper lining, an insole layer, and a layer of insole foam, and the outsole forming the exterior bottom of the shoe;

the midsole comprising a shape retentive, resilient material that resiliently conforms along the longitudinal axis of the shoe with the flexion of the foot but resists substantial compression along the vertical axis of the midsole during use of the shoe, and the midsole located at the forefoot portion of the shoe to support the toes and the metatarsal heads of a foot; the outsole being relatively less conforming to the foot than the midsole; and a shoe upper attached to the outsole, the midsole, and insole by cement lasting to form a foot enclosure.

21. The shoe of claim 20, wherein the midsole has a thickness ranging between about 0.5 cm at a peripheral portion to about 1.5 cm at a central portion.

22. The shoe of claim 20, wherein the midsole has a central portion with a thickness ranging between about 1.5 cm and about 2.0 cm.

23. The shoe of claim 20, wherein the midsole is provided with a recess at the toe portion of the shoe allowing the upper of the shoe to fit into the recess when attaching the upper to the midsole and the outsole of the shoe thereby providing a smooth transition zone between the shoe upper and sole of the shoe.

24. The shoe of claim 23, wherein the upper attaches to the midsole by pleats fitted within the recess of the midsole.

25. A method for making a flexible platform shoe, comprising: providing a last with a shoe upper, an insole, a midsole, and an outsole; forming a forefoot portion of the shoe covering the metatarsal heads and toes of the foot, the forefoot portion comprising a midsole disposed between an

insole and an outsole, the midsole comprising a shape retentive, resilient material that conforms along the longitudinal axis of the shoe with the flexion of the foot but resists substantial compression along the vertical axis of the midsole during use of the shoe, and the outsole being relatively less conforming to the foot than the midsole; forming a midfoot portion covering the arch of the foot, and comprising a substantially rigid arch support spanning from the heel portion to the forefoot portion; forming a heel portion covering the heel of the foot, and comprising a substantially rigid 'heel, raising a user's heel at least 3.5 cm above a ground surface; and cement lasting the upper, the insole, the midsole, and the outsole to create a foot enclosure.

26. The method of claim 25, wherein the midsole comprises expanded injection ethylene vinyl acetate with an average hardness of about 70 Asker C durometer.

27. A flexible platform shoe, comprising: a heel portion, a midfoot portion, and a forefoot portion; the heel portion covering the heel of the foot; the midfoot portion covering the arch of the foot; the forefoot portion covering the metatarsal heads and toes of the foot; the heel portion comprising a substantially rigid heel, raising a user's heel at least

3.5 cm above a ground surface; the midfoot portion comprising a substantially rigid arch support spanning from the heel portion to the forefoot portion; and

the forefoot portion comprising a midsole disposed between an insole and an outsole, the midsole comprising a shape retentive, resilient material that resiliently conforms along the longitudinal axis of the shoe with the flexion of the foot but resists substantial compression along the vertical axis of the midsole during use of the shoe, and the outsole being relatively less conforming to the foot than the midsole, the midsole comprising a peripheral portion along lateral and medial sides having a first thickness and a central portion having a second thickness greater than the first thickness.

28. The shoe of claim 27, wherein there is a stepped transition from the peripheral portion to the central portion.

29. The shoe of claim 27 wherein the thickness between peripheral and central portions differs by at least about 1.0 cm.

30. The shoe of claim 27 wherein the peripheral portion is at least about 0.5 cm and the central portion is at least about 1.5 cm and the difference between the two is at least about 1.0 cm.

Description:

FLEXIBLE PLATFORM SHOE Inventor: David Wilkenfeld

RELATED APPLICATIONS This application claims priority from U.S. Provisional Application Number

61/034,465, filed March 6, 2008, and U.S. Provisional Application Number 61/034,790, filed March 7, 2008, the contents of which are hereby incorporated by reference as if recited in full herein for all purposes.

BACKGROUND

The inventive subject matter disclosed herein is generally directed to a high heel shoe, in particular to a high heel shoe with a flexible platform. The shoe combines desirable features from a high heel fashion shoe, a platform shoe and a flexible cushioned athletic shoe. Platform shoes are shoes, boots, or sandals with thick midsoles or outsoles, often made of cork, plastic, rubber, or wood. In platform shoes, both the forefoot and the heel are significantly raised above the ground. In dance, platform shoes tend to give the illusion of longer and more slender legs, but poor design can be detrimental to dance performance. A high heel shoe is a shoe which raises the heel of the wearer's foot significantly higher than the toes. High heel shoes come in a wide variety of styles, and the heels are found in many different shapes, including Cuban, stiletto, pump, block, tapered, blade, or wedge. The height of these heels varies, for example, from a Cuban heel of 3.5 cm (1.4 inches) height to a stiletto heel of 10 cm (4 inches) or more.

Shoes generally have a shoe upper and a sole attached to the upper. The shoe upper helps to hold the shoe onto the foot, hi the simplest cases, such as sandals or flip flops, this may be nothing more than a few straps for holding the sole in place. Closed footwear, such as boots, sneakers, and most men's shoes, will have a more complex upper. The shoe upper is often decorated or is made in a certain style to look attractive. The sole of the shoe typically has several layers. For example, in athletic shoes, the midsole of a shoe is a layer in between the insole and the outsole. Such a midsole is typically used for shock absorption. Some types of shoes, like running shoes, may have a combination of materials or structures for shock absorption, usually beneath the heel where one puts the most pressure down. The outsole of a shoe is the layer in direct contact with the ground, forming the exterior bottom of the shoe. Dress shoes typically have leather outsoles, while casual or work-oriented shoes may have outsoles made of relatively hard natural rubber or a synthetic material.

Platform shoes and high heel shoes traditionally have rigid soles because of the materials used and their method of construction which is usually by cement lasting, hi contrast, conventional athletic shoes usually have soles providing cushioning and flexibility, allowing the shoe to absorb shock and resiliently conform with the flexion of the foot. Athletic shoes are typically made by stitching a foot enclosing upper before attaching the enclosure to a midsole and outsole assembly. These shoes often use molded midsoles of ethylene vinyl acetate (EVA), because of its shock absorbing properties.

None of the existing shoes, however, combines the features of a high heel shoe and a platform shoe with the features of a flexible athletic shoe that allows the shoe to conform along the longitudinal axis of the shoe with the flexion of the foot.

Unfortunately, attempts to make such shoes have resulted in shoes having an unstable platform sole due to the compliant and flexible nature of the sole material, such as EVA, which creates lateral instability because of the compressibility of the material in the vertical axis of the platform. A flexible platform shoe is distinguishable over regular high heel shoes with a rigid platform, which provides little conformance with the flexion of the foot, and over shoes with separate cushioning inserts that are often added for comfort or health reasons.

Accordingly, there is a need for a flexible platform shoe having a flexible and light-weight platform, which allows the shoe to flex with the foot along the longitudinal axis when walking or dancing, but which resists substantial compression along the vertical axis of the platform and the concomitant lateral instability.

SUMMARY

The inventive subject matter offers a solution for these problems by providing a high heel shoe with the following qualities, alone or in combination. The inventive subject matter is directed to a flexible platform shoe, having a heel portion, a midfoot portion, and a forefoot portion, the heel portion of the shoe covering the heel of the foot, the midfoot portion of the shoe covering the arch of the foot, and the forefoot portion of the shoe covering the metatarsal heads and toes of the foot, the heel portion having a substantially rigid heel, raising a user's heel at least 3.5 cm above a ground surface, the midfoot portion having a substantially rigid arch support spanning from the heel portion to the forefoot portion, the forefoot portion having a midsole disposed between an insole and an outsole, the midsole having a shape retentive, resilient material that resiliently conforms along the longitudinal axis of the shoe with the flexion

of the foot, but resists substantial compression along the vertical axis of the midsole during use of the shoe, and the outsole may be relatively less conforming to the foot than the midsole.

In the foregoing and other embodiments, the forefoot portion may raise the user's foot at least 0.5 cm above a ground surface. In the foregoing and other possible embodiments, the forefoot portion raises the user's foot about 1 cm above a ground surface. In the foregoing and other possible embodiments, the midsole may have a peripheral portion with a thickness of about 0.5 cm and a central portion with a thickness of about 2 cm. hi the foregoing and other possible embodiments, the midsole may a central portion with a thickness of about 1.5 cm, about 2.0 cm, or ranging between about 1.5 cm and about 2.0 cm. hi the foregoing and other embodiments, the midsole may have a foam material with an average hardness ranging between about 45 Asker C and about 95 Asker C durometer, ranging between about 60 Asker C and about 80 Asker C durometer, or with an average hardness of about 70 Asker C durometer. hi the foregoing and other embodiments, the midsole may include a material including a shape retentive, flexible polymer, such as an injection molded foam, for example ethylene vinyl acetate with an average hardness ranging between about 45 Asker C and about 95 Asker C durometer, ranging between about 60 Asker C and about 80 Asker C durometer, or with an average hardness of about 70 Asker C durometer. hi the foregoing and other embodiments, the midsole may be dimensioned to reside from a toe portion of the shoe to the midfoot portion of the shoe with the midsole vertical cross section thinning towards the midfoot portion of the shoe. In the foregoing and other embodiments, the width of the midsole may approximately mirror the shape and width of the overlying region of the wearer's foot, hi the foregoing and other embodiments, the midsole may be

dimensioned to have its thickest vertical cross section in the central portion of the midsole and its thinnest vertical cross section at the toe tip of the midsole. hi the foregoing and other embodiments, the heel may have a height of at least 5.0 cm.

In another possible embodiment, the inventive subject matter is directed to a flexible platform shoe, having a heel portion, a midfoot portion, and a forefoot portion, the heel portion of the shoe covering the heel of the foot, the midfoot portion of the shoe covering the arch of the foot, the forefoot portion of the shoe covering the metatarsal heads and toes of the foot, the heel portion having a substantially rigid heel, raising a user's heel at least 3.5 cm above a ground surface, the midfoot portion having a substantially rigid arch support spanning from the heel portion to the forefoot portion, the forefoot portion having a midsole disposed between an insole and an outsole, the insole forming the interior bottom of the shoe having an upper lining, an insole layer, and a layer of insole foam, and the outsole forming the exterior bottom of the shoe, the midsole further having a shape retentive, resilient material that resiliently conforms along the longitudinal axis of the shoe with the flexion of the foot, but resists substantial compression along the vertical axis of the midsole during use of the shoe, the midsole located at the forefoot portion of the shoe to support the toes and the metatarsal heads of a foot, the outsole being relatively less conforming to the foot than the midsole, and a shoe upper attached to the outsole, the midsole, and the insole by cement lasting to form a foot enclosure.

In the foregoing and other possible embodiments, the midsole may have a thickness ranging between about 0.5 cm at a peripheral portion to about 1.5 cm at a central portion. In the foregoing and other possible embodiments, the midsole may have a central portion with a thickness ranging between about 1.5 cm and about 2.0 cm. In the

foregoing and other embodiments, the midsole may further have a recess at the toe portion of the shoe allowing the upper of the shoe to fit into the recess when attaching the upper to the midsole and the outsole of the shoe thereby providing a smooth transition zone between the shoe upper and sole of the shoe. In the foregoing and other embodiments, the upper may attached to the midsole by pleats fitted within the recess of the midsole.

The inventive subject matter further contemplates a method for making a flexible platform shoe, by providing a last with a shoe upper, an insole, a midsole, and an outsole, forming a forefoot portion of the shoe by covering the metatarsal heads and toes of the foot, the forefoot portion having a midsole disposed between an insole and an outsole, the midsole having a shape retentive, resilient material that resiliently conforms along the longitudinal axis of the shoe with the flexion of the foot but resists substantial compression along the vertical axis of the midsole during use of the shoe, and the outsole being relatively less conforming to the foot than the midsole, forming a midfoot portion by covering the arch of the foot, having a substantially rigid arch support spanning from the heel portion to the forefoot portion, a heel portion, covering the heel of the foot, having a substantially rigid heel, raising a user's heel at least 3.5 cm above a ground surface, and cement lasting the upper, the insole, the midsole, and the outsole to create a foot enclosure. In the foregoing and other embodiments, the midsole may have expanded injection ethylene vinyl acetate with an average hardness of about 70 Asker C durometer.

In another possible embodiment, a flexible platform shoe, may include a heel portion, a midfoot portion, and a forefoot portion, the heel portion covering the heel of the foot, the midfoot portion covering the arch of the foot, the forefoot portion covering the metatarsal heads and toes of the foot, the heel portion comprising a substantially rigid

heel, raising a user's heel at least 3.5 cm above a ground surface, the midfoot portion including a substantially rigid arch support spanning from the heel portion to the forefoot portion, and the forefoot portion including a midsole disposed between an insole and an outsole, the midsole including a shape retentive resilient material that resiliently conforms along the longitudinal axis of the shoe with the flexion of the foot but resists substantial compression along the vertical axis of the midsole during use of the shoe, and the outsole being relatively less conforming to the foot than the midsole, the midsole including a peripheral portion along lateral and medial sides having a first thickness and a central portion having a second thickness greater than the first thickness, hi the foregoing and other possible embodiments, there may be a stepped transition from the peripheral portion to the central portion, hi the foregoing and other possible embodiments, the thickness between peripheral and central portions may differ by at least about 1.0 cm. hi the foregoing and other possible embodiments, the peripheral portion may be at least about 0.5 cm and the central portion may be at least about 1.5 cm and the difference between the two may be at least about 1.0 cm.

These and other embodiments are described in more detail in the following detailed descriptions and the figures.

The foregoing is not intended to be an exhaustive list of embodiments and features of the inventive subject matter. Persons skilled in the art are capable of appreciating other embodiments and features from the following detailed description in conjunction with the drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

The following figures show embodiments according to the inventive subject

matter, unless noted as showing prior art.

FIG. 1 shows a side view of a flexible platform shoe while the wearer is walking and the heel of the shoe is lifted off the ground.

FIG. 2 shows a cross-section of a pleated toe platform construction. FIG. 3 shows a simplified bottom view of a midsole.

FIG. 4 shows a bottom view of a pleated forefoot portion of a flexible platform shoe.

FIG. 5 shows a side view of another flexible platform shoe.

FIG. 6 shows a Physical Properties Testing Report illustrating durability and performance of an EVA midsole.

DETAILED DESCRIPTION

Representative embodiments according to the inventive subject matter are shown in FIGS. 1-6, wherein the same or generally similar features share common reference numerals. The inventive subject matter is generally directed to a high heel shoe having a flexible and light weight platform construction that combines the desirable features of a high heel shoe, a platform shoe and an athletic shoe.

In general, a shoe has a heel portion, a midfoot portion, and a forefoot portion.

The heel portion of the shoe covers the heel of the foot, below the calcaneus bone. The heel is raised significantly. For high heel shoes, the heel may raise a user's heel at least

3.5 cm (1.4 inches) or higher above a ground surface. The midfoot portion of the shoe covers the arch of the foot, formed by the tarsal bones. The forefoot portion is the area of the shoe that covers the toes and metatarsal heads of the foot. In addition to the heel

portion being raised, the forefoot portion is also significantly raised. A significantly raised forefoot, as contemplated in this patent document, is one that is raised at least 0.5 cm above the ground.

A shoe according to one embodiment of the inventive subject matter has a midfoot portion with a substantially rigid arch support spanning from the heel portion to the forefoot portion. The forefoot portion has a midsole functionality, which is typically a material disposed between an insole and an outsole. The midsole of the inventive subject matter typically is a foamed material that resiliently conforms along the longitudinal axis of the shoe with the flexion of the foot, but resists substantial compression along the vertical axis of the midsole during use of the shoe. Therefore the lateral stability of the foot is not affected. Additionally, the outsole is relatively less conforming to the foot than the midsole. As used herein "flexion" of the foot refers to the motions of the foot and ankle in general, for example as they occur when walking or dancing, including bending of the foot at the metatarsal joints and ankle. While the midsole is generally discussed as a discrete component, persons in the art will recognize that a single unit may provide midsole, insole, and/or outsole functionalities.

FIG. 1 shows a foot 3 of a wearer with a flexible platform shoe 1, according to one possible embodiment of the inventive subject matter. Shoe 1 has a shoe upper 13 and a sole 15. Shoe 1 further has a heel portion 5, a midfoot portion 7, and a forefoot portion 9. Forefoot portion 9 includes a toe portion 11. The person wearing the shoe is lifting the heel 5 of shoe 1 of the ground, as occurs when walking or turning. This illustrates foot flexion. The arch of the foot is supported by a rigid arch support 8, such as a steel shank. Such a shoe has a heel with a dimension X, as indicated in FIG. 1, referring to the total height of the heel from the ground to the top surface of the insole, of at least 3.5 cm.

Dimension Y, indicated in FIG. 2, refers to the height of the platform at the forefoot portion of the shoe, which is at least 0.5 cm from the ground to the top surface of the insole. Such a shoe also has a dimension Z, which refers to the height that the heel of the foot is raised relative to the toes of the foot. Dimension Z corresponds to the difference between dimensions X and Y. For example, a shoe with a platform height of 0.5 cm and a heel height of 3.5 cm, raises the heel of the foot 3 cm relative to the toes of the foot. FIG. 2 illustrates how shoe 1 may be formed over a last 17. A sole 15 may be made of multiple layers, for example, an insole 19, a midsole 27, and an outsole 21. Insole 19 forms the interior bottom of shoe 1, sitting directly beneath the foot. Outsole 21 is the layer in direct contact with the ground and forms the exterior bottom of shoe 1. The outsole may be a single piece, or may be formed of separate pieces of different materials. Insole 19 may be padded with additional layers for comfort. For example, an insole foam layer 25 is padded with a California upper lining 23, which forms a contact surface with the bottom of the foot. To form a foot enclosure, shoe upper 13 is fastened to outsole 21 and midsole 27.

The upper positions, supports, and protects the foot.

Midsole 27 is a light-weight platform located at forefoot portion 9 of the shoe to support the toes and metatarsal heads of a foot. Midsole 27 is spaced between insole 19 and outsole 21. As shown in FIG. 2, midsole 27 is dimensioned to reside from a toe portion 11 of the shoe to the midfoot portion 7 of the shoe. Furthermore, midsole 27 may also be contoured to the forefoot portion of a foot. For example, FIG. 3 shows a bottom view of a midsole wherein the width of the midsole 27 approximately mirrors the shape and width of the overlying region of the wearer's foot. Additionally, midsole 27 may have zones of different resilience provided by for example varying the thickness of the

midsole or material properties of it. For example, midsole 27 has a central portion 29 and a peripheral portion 30. The vertical cross-sectional thickness of central portion 29 is greater than that of the peripheral portion 30, thereby creating a central raised surface. The transition from peripheral portion 30 to central portion 29 may be stepped at the contours of central portion 29 or there may be a gradual change in thickness from the peripheral portion to the central portion. In a vertical cross-section of midsole 27 the raised central portion creates zones of different thickness, for example at a location towards the midfoot portion of the midsole a medial zone D, central zone E, and lateral zone F represent areas of different midsole thickness. In some embodiments, the thickness of the midsole may vary within a certain zone. For example, central portion 29 is dimensioned to have its thickest portion in central portion 29 of the midsole 27 and on lateral side 31 and medial sides 33 of midsole 27 along a section C of the midsole 27. The thinnest portion of midsole 27 is at toe tip 35 of midsole 27, i.e., the area of the platform located beneath the toes of the foot. FIG. 2 shows midsole 27 with a maximum vertical cross-sectional thickness A below the metatarsal heads of the foot. The vertical cross-section of midsole 27 is thinning towards the midfoot portion 7 of the shoe 1. For example, vertical cross-sectional thickness B is less than cross sectional thickness A. In other possible embodiments, the midsole may have a maximum thickness at the central portion of 1.5 cm or 2.0 cm, or somewhere in between. In some suitable embodiments, the midsole thickness may range anywhere from 0.5 cm to 2.0 cm. In a vertical cross- section the width of the respective zones D, E, and F may vary. For example, as shown in FIG. 3, central zone E corresponds to a central portion 29 which widens gradually in a section C and narrows towards toe tip 35. Medial zone D and lateral zone F correspond

to a peripheral portion 30. These zones follow the contours of the central portion and become wider at toe tip 35 where the central portion ends and zones D and E merge.

Another possible embodiment of a flexible platform shoe is shown in FIGS. 4 and 5. A shoe 1 has an upper 13 that attaches to sole 15. Upper 13 folds over toe portion 11 towards sole 15 with pleating 37 formed by the upper material at the bottom of shoe 1. Similar pleating is often found in ballet flats. Pleating 37 of upper 13 may be fitted within a recess 50 of midsole 27 and outsole 21, as shown in FIG. 2.

A shoe of European size 37 Vi is shown in FIGS. 4-5. The shoe has midsole with a maximal length of about 14 cm, a maximal width of about 7.5 cm, and a maximal thickness of about 1 cm. The height of the heel is about 8 cm. These are exemplary dimensions only and may be adjusted by one skilled in the art.

Midsole 27 may be formed of a foamed material, such as a shape retentive, flexible polymer. The foamed material provides the midsole with a cushioning structure suitable for absorbing the shock of landing, i.e., the midsole provides for a padded feeling beneath the foot. The material, however, does not compress substantially to affect lateral movement of the foot, nor does the material depress significantly to make the shoe unstable. In particular, an injection molded foam, such as ethylene vinyl acetate (EVA) may be used. EVA is a polymer that approaches elastomeric materials in softness and flexibility, yet can be processed like other thermoplastics. Furthermore, EVA has little or no odor and is competitive with rubber and vinyl products in many applications. Other suitable foam polymers or rubber mixed with compounds may be used to form midsoles according to the inventive subject matter, including those of polyurethane, thermoplastic rubber, and nitrol polyvinyl chloride. It is also understood that midsoles may be formed as a single piece structure or as a combination of multiple layers.

FIG. 6 shows a Physical Properties Testing Report of a midsole platform according to one embodiment of the invention. These data are intended as guide posts to help those skilled in the art arrive at a suitable midsole construction. The test results herein are believed to be accurate and reproducible. However, the test results are intended to supplement the foregoing teachings, and, as is always the case with any experiment, may not have been carried out in a manner that is perfectly in accordance with scientific principles or otherwise beyond question. Accordingly, the following test results should be viewed as prophetic in nature, but the Applicant reserves the right to rely on them as actual experiments should it be necessary to overcome certain kinds of rejections that might arise during the examination.

The test results were performed on a midsole platform formed of EVA material for a pleated flexible platform shoe, as described above. The EVA material has an average hardness of 70 Asker C durometer. Asker C refers to a type of measuring device to measure hardness with a durometer. In particular, Asker C is a hardness scale used to measure materials that are harder than those measured in a needle penetration test and softer than those for a JIS (Japanese Industrial Standards) A durometer. Larger numbers on the Asker C scale indicate a harder material.

The testing report in FIG. 6 shows a Compression Set percentage of 60.95 %, performed for 6 hours at 50° C. Compression Set testing is used to determine the ability of elastomeric materials to maintain elastic properties after prolonged compressive stress. The test measures the permanent deformation of the specimen after it has been exposed to compressive stress for a set time period. This Compression Set percentage of the material is significant in ensuring that the midsole retains its shape during construction of the shoe with a cement lasting method, as described below. However, the flexibility of the

platform is equally determined by design and thickness mechanics, as described above. The Test Report further shows test results for tear resistance with an average of 15.79 kg/cm; tensile strength with an average of 28.24 kg/cm 2 ; elongation with an average % of 362.67; split tear with an average of 2.81 kg/cm; specific gravity with an average of 0.227 g/cm 3 ; and shrinkage of 0.37 %.

The inventive subject matter further contemplates a method for making a flexible platform shoe by a cement lasting process which ensures that the midsole maintains its resilience and the desired shape while the shoe is formed. Typically, shoes are built around a last that resembles the shape of a foot. The resulting shape of the shoe depends on the shape of the last, the lasting process, and the materials from which the shoe is made. A method for forming a shoe with a last is shown in FIG. 2. According to one exemplary method, a last may be provided with several layers of soles using the following steps. An insole is attached to the bottom of the last. A midsole, in the form of a flexible, light weight EVA platform is glued to the insole. The last is further provided with a shoe upper which does not have a bottom portion. The upper may be cemented on the edges of soles to the insole and midsole to create a foot enclosure. Subsequently, an outsole is glued to the upper and midsole. The glue hardens to act as an adhesive between the different layers.

This method allows using a cementing process, while also retaining the flexibility of the midsole. hi general, a cementing process constructs a shoe by cementing, that is by gluing, rather than by stitching, the upper of the shoe to the sole of the shoe. During one example process, separate components of the shoe may be glued together and then left for 10-15 minutes to partially dry. Subsequently, the glued components may be heated to activate the glue, put together, and combined in a pressure machine used to apply

force/weight to the glued components. During this cementing process the materials of the soles are under stress. The method requires that the midsole is formed of a material that is hard enough to maintain its shape, i.e., the midsole does not distort while the shoe is lasted, and thereby results in a midsole platform that does not depress substantially under the weight of a wearer. In particular, the EVA material described above has been made harder than the EVA material usually used in an athletic shoe thereby allowing the cement lasting construction method of the shoe.

Attempts of lasting a shoe with a midsole using a conventional polyurethane material were less successful because the polyurethane midsole tends to lose its shape and flexibility during the lasting process. For example, a cement lasting process using a polyurethane midsole that was hard enough to maintain its shape during the lasting process, provided a midsole that was so hard that there was a risk of cracking at low temperatures.

A flexible platform shoe according to the inventive subject matter may come in different styles. For example, a platform may be formed by either raising a midsole or a outsole. The density of the material, the shapes, and the margins of movement may vary, as well as the structure of the sole.

Persons skilled in the art will recognize that many modifications and variations are possible in the details, materials, and arrangements of the parts and actions which have been described and illustrated in order to explain the nature of the inventive subject matter, and that such modifications and variations do not depart from the spirit and scope of the teachings and claims contained therein.

Any patent and non-patent literature cited herein is hereby incorporated by references in its entirety for all purposes.