BREATHABLE AND WATERPROOF FOOTWEAR
20220400809 · 2022-12-22
Inventors
Cpc classification
A43B13/38
HUMAN NECESSITIES
A43B7/125
HUMAN NECESSITIES
International classification
Abstract
A footwear includes an upper attached to a sole. The upper includes an outer layer and an inner membrane. The outer layer has a lower end. The lower end of the outer layer has an outer layer lower edge. The membrane includes a lower end of the membrane. The lower end of the membrane has a lower edge of the membrane. The membrane (MEM) is suspended within the footwear between an upper circumference of the upper and a lower anchoring circumference by means of an anchoring adhesive. The lower end of the membrane is stitched to the insole along a lower circumference. The upper circumference is lower than the top edge of the footwear.
Claims
1. A footwear comprising: an upper attached to a sole (S), the upper comprising an outer layer (OL) and an inner membrane (MEM), wherein the outer layer (OL) comprises a lower end (LOL), the lower end (LOL) of the outer layer having an outer layer lower edge (LEOL), wherein the membrane (MEM) comprises a lower end of the membrane (LMEM), the lower end of the membrane (LMEM) having a lower edge of the membrane (LEMEM), wherein the membrane (MEM) is suspended within the footwear between an upper circumference (UC) of the upper and a lower anchoring circumference (LAC) by means of an anchoring adhesive (AA), wherein the lower end of the membrane (LMEM) is stitched to an insole (IS) along a lower circumference (LC), and wherein the upper circumference (UC) is lower than a top edge (TE) of the footwear (FW).
2. The footwear according to claim 1, wherein the lower end of the membrane (LMEM) is further attached to the sole (S).
3. The footwear according to claim 1, wherein the lower end of the membrane (LMEM) is stitched to the insole (IS) along the lower circumference (LC) without perforating the lower end of the outer layer (LOL).
4. The footwear according to claim 1, wherein the lower end of the membrane (LMEM) projects further below the lower edge of the outer layer edge (LEOL) towards the insole (IS).
5. The footwear according to claim 1, wherein the sole (S) of the footwear defines a sole upper edge (SUE) at the outside of the footwear defining a transition between the sole and the outer layer.
6.-7. (canceled)
8. The footwear according to claim 1, wherein a cross-section of the lower end of the membrane (LMEM) is curved towards the insole.
9. The footwear according to claim 8, wherein the cross-section of the lower end of the membrane (LMEM) and the insole (IS) is curved towards the stitching (STI) between the insole (IS) and the lower end of the membrane (LMEM).
10. The footwear according to claim 9, wherein a curve of the cross-section is approximating an arc.
11. The footwear according to claim 1, wherein the membrane (MEM) is attached to the upper at the upper circumference (UC) by stitching.
12. (canceled)
13. The footwear according to claim 5, wherein the anchoring adhesive (AA) is attached to an inside of the outer layer (LOL) at a vertical direction which is lower than the sole upper edge (SUE).
14.-15. (canceled)
16. The footwear according to claim 5, wherein a distance (DIST A) between the sole upper edge (SUE) and the lower edge of the membrane (LMEM) is at least 12 mm and wherein a distance (DIST B) between the lower edge of the outer layer (LEOL) and the lower edge of the membrane (LEMEM) is at least 4 mm but not greater than 25 mm.
17. The footwear according to claim 16, wherein the distance (DIST B) between the sole upper edge (SUE) and the lower edge of the outer layer (LEOL) is at least 5 mm.
18. The footwear according to claim 1, wherein the lower end of the membrane (LMEM) is sealed to the sole (S) directly by cementing or by direct injection process of the sole onto the membrane.
19. (canceled)
20. The footwear according to claim 1, wherein a height of the anchoring adhesive (AA) is between 4 to 20 mm.
21. The footwear according to claim 1, wherein a horizontal distance (H DIST) between the lower edge of the outer (LOL) and the lower edge of the membrane (LEMEM) is shorter than a distance between the lower edge of the outer (LOL) and the lower edge of the membrane (LEMEM) along the lower end of the membrane.
22.-24. (canceled)
25. A method of manufacturing a footwear comprising an upper attached to a sole, the upper comprising an outer layer (OL) and an inner membrane (MEM), wherein the outer layer (OL) comprises a lower end (LOL), the lower end (LOL) of the outer layer having an outer layer lower edge (LEOL), wherein the membrane (MEM) comprises a lower end of the membrane (LMEM), the lower end of the membrane (LMEM) having a lower edge of the membrane (LEMEM), wherein the membrane (MEM) is suspended within the footwear between an upper circumference (UC) of the upper and a lower anchoring circumference (LAC) by means of an anchoring adhesive (AA), wherein the lower end of the membrane (LMEM) is stitched to an insole (IS) along a lower circumference (LC), and wherein the upper circumference (UC) is lower than the top edge (TE) of the footwear (FW), the method comprising: suspending the membrane (MEM) between the upper circumference (UC) and the lower anchoring circumference (LAC) so as to have no adherence to the outer layer.
26. The method according to claim 25, wherein the upper (U) is lasted prior to attaching the sole to the upper and wherein the sole is attached to the upper by a direct injection process and wherein the direct injection process when performed attaches to the lower end of the membrane around the circumference of the lower end of the membrane thereby sealing the membrane to a circumference of the sole.
27. (canceled)
28. The method according to claim 25, wherein both the lower end of the outer layer LOL and the insole is curved during a lasting process to as to make the lower end of the membrane available for cementing of a sole from below.
29. The method according to claim 25, wherein both the lower end of the outer layer LOL and the insole is curved during a lasting process so as to make the lower end of the membrane available for cementing of a sole from below and wherein a distance between the lower edge of the outer layer LEOL and the lower edge of the membrane LMEM (DIST B) is between 4 and 15 mm.
30. (canceled)
Description
THE FIGURES
[0184] The invention will now be described with reference to the drawing where
[0185]
[0186]
[0187]
[0188]
[0189]
DETAILED DESCRIPTION
[0190]
[0191] The outer layer OL comprises two surfaces; a surface OSF that faces the foot insertion volume FIV of the upper U, and a surface OSO that is facing outwards and in the opposite direction of a surface OSF that faces the foot insertion volume FIV.
[0192] The membrane MEM comprises two surfaces; a surface BSF that faces the foot insertion volume FIV of the upper U, and a surface BSO that is facing the outer layer surface OSF.
[0193] The upper has a top edge TE, here defining the upper end of the footwear.
[0194] The upper U may comprise more than two layers, where a third, fourth or subsequent layers may be provided. The membrane MEM however should be positioned between the foot insertion volume FIV and the outer layer of the upper, in order to prevent liquids to enter the foot insertion volume. Further layers and/or attachments may of course be applied within the scope of the invention.
[0195] The upper U has an upper part UP and a lower part LP, where the lower part LP abuts the upper facing surface UFS of the sole S. The sole S has a sole upper edge SUE. The sole may comprise several parts and layers (not shown).
[0196] The sole S further has a ground contacting surface GCS, which is intended to come into contact with the ground when the article of footwear FW is worn by a user. In accordance with one or more embodiments the sole S may comprise a midsole, where the ground contacting surface GCS may be an outsole facing surface, in case there is an outsole applied between the midsole and the ground, or any other form for a sole part located between the ground and the midsole. Thus, the term ground contacting surface may be replaced by the term ground facing surface.
[0197] The outer layer OL has a lower end LOL that extends past the sole upper edge SUE of the upper surface and extends in a, preferably, downward direction towards the bottom BUA of the upper and both a lower end of the membrane LMEM and the lower end of the outer layer LOL forms a part of an area where the upper U and the sole S are joined. The lower end of the membrane is furthermore connected to an insole IS around the circumference of the insole IS. The insole may optionally be connected by means of stitching and thus forming part of the upper. This may also be referred to as a strobel stitching. It should be noted, unless otherwise specified, that the stitching is optional and other means of connecting the insole to the upper may be applied within the scope of the invention, e.g. by means of adhesion.
[0198] As may be seen in
[0199] The illustrated footwear may in principle be manufactured as both a cemented footwear, i.e. where the sole S is cemented to a pre-manufactured upper U and a footwear manufactured by direct-injection, i.e. where the sole is molded onto the upper by a direction injection process. These two processes are known in relation to conventional footwear, but is should be noted that the method needs specific and unique modifications to be applied in the context of the present invention.
[0200] Other methods which may be applied within the scope of embodiments of the invention may include vulcanization of rubber onto the upper, casted sole or e.g. 3D printing directly onto the lower end of the upper.
[0201] In connection with the gathering of the upper with a sole, the above manufacturing methods may preferably include a roughing step if the outer layer is a top grain leather layer. At least a part of the lower end of the outer layer LOL should thus be roughed in order to e.g. attach to the cement or the DIP (DIP: Direct injection process) material to be used.
[0202] In an area where the outer layer OL and the membrane MEM overlap, they may be attached by an anchoring adhesive AA. The anchoring adhesive AA is applied for the purpose of securing the membrane to the outer layer OL around the lower end of the membrane thereby ensuring that the membrane do not fold inside the shoe. The adhesive also serves as a means for ensuring that adhesive, when sole S is attached by cementing does not progress to much between the membrane MEM and the outer layer OL. If the shoe is made by means of direct injection, the sole S would be attached to the upper by means of a direct-injection-process. In such a case, the anchoring adhesive should furthermore serve, preferably as a continuous or as a part of a continuous anchoring around the complete circumference of the lower end of the upper, thereby ensuring that the material applied for direct injection is not progressing or foaming in between the membrane and the outer layer in a undesired and unpredictable way.
[0203] The above illustrated embodiment of the invention may serve as a reference for different aspects of the present invention below. It should nevertheless be noted that the aim would overall to achieve a footwear which is waterproof above the lower end of the upper, i.e. the lower end of the membrane LMEM and the lower end of the outer layer LOL. How high such waterproofness is required may depend on the footwear design as long as it goes above the lower end of the outer layer. The outer layer OL and the membrane should also be breathable.
[0204] The waterproofness is fully required from above the lower end of the membrane and included the lower part of the upper, including the sole S. It should be noted that the waterproofness at the lower end of the footwear FW is primarily designed to keep the inside of the footwear waterproof. In other words. The combination of the outer layer and the membrane must ensure waterproofness with respect to water passing from there into the foot insertion volume FIV. It may be a little different with respect to the lower part LP of the upper in combination with the sole S, as the breathability through the sole is not and absolute requirement, but it is necessary that the water does not pass into the foot insertion volume FIV. This means that there is degree of freedom in terms of design when establishing the sole structure. A part of the sole, e.g. the lower part may thus be non-waterproof as long as the a part of the sole S or the insole IS comprise a waterproof barrier which may prevent water from passing from the outside of the footwear FW into the foot insertion volume FIV through the sole S of through the critical transition between the lower end of the membrane LMEM and the insole IS and/or the sole S.
[0205] A part of such waterproof barrier may thus in another embodiment by implemented by the application of a waterproof sole which is connected in a waterproof way the membrane of the upper.
[0206] It should thus be noted that, according to an embodiment of the invention, that both the upper U and the S/insole IS are applied as breathable and waterproof, whereas another attractive embodiment of the invention is waterproof and breathable with respect to the upper (at least the lower part of the upper) and only waterproof with respect to the sole and/or the insole.
[0207] When the sole S is attached to the upper either by cementing or by a direct a process a sole upper edge SUE is formed at this transition between the sole and the upper on the outside of the footwear
[0208] The lower end of the outer layer LOL is ending at lower edge of the outer layer LEOL and the lower end of the membrane LMEN ends at a lower edge of the membrane LEMEM.
[0209] The sole is preferably waterproof in the embodiments of the invention.
[0210] The lower end of the membrane LMEM is stitched by stitching STI to the insole IS around the insole at a lower circumference LC.
[0211] In the upper part UP, the membrane is stitched to the outer layer and optionally to further footwear components, e.g. a tongue (not shown). The stitching may also be referred to as being an attachment arrangement ATTA by means of which the membrane is attached at an upper circumference UC, here by stitching. In the present embodiment, the membrane is stitched to e.g. a collar COL or a lining which e.g. may be attached to the very upper top end, e.g. by stitching and/gluing. Alternatively, and not shown, the upper end of the membrane MEM may be attached around the upper circumference by stitching directly with the outer layer OL.
[0212] The difference between the first mentioned and the last mentioned embodiment is thus that the membrane in the latter embodiment it stitched directly to the outer layer whereas the first embodiment rather is a suspension, where the membrane is stitched or attached to the outer at the top of the footwear via an intermediate member(s), thereby avoiding stitching in the top of the outer layer besides at the very top of the upper.
[0213] The upper circumference will not necessarily form an unbroken line, but is preferred that the upper circumference is an unbroken line.
[0214] Furthermore, the MEM is attached to the outer layer by an anchoring adhesive AA around a lower anchoring circumference LAC.
[0215] It is further noted that the lower anchoring circumference lower should preferably ensure a continuous and non-folded attachment of the membrane to the outer layer as folding may result in a erroneous DIP or cementing process, which is in particular critical in relation to the DIP process.
[0216] In the present context an insole should be referred to as a part of the sole, which is applied to form a kind of sock for accommodating the foot of a user when the insole is stitched to the upper. This sole may by some be referred to as a strobel sole, but in the present context the insole is functionally understood as a part of the sole which is forming an anchoring interface to the sole below. It is in particular noted that the stitching of the insole in practice is performed prior to either cementing or direct injection of a sole to the upper. The stitching is not a part of these two types of processes in the present context. Thus, further sole(s) may be inserted into the footwear as basically a loose and exchangeable part of the footwear within the scope of the invention without compromising the above understanding of what an insole is.
[0217] The sole as such may comprise a combination of the insole, an outer sole and further optional sole layers or members. In the present context an insole may be regarded as a part of the sole due to its durable attachment to the sole. It is noted that such understanding may be derived from in different context, e.g. because the insole may rather be regarded as a part of the upper during manufacture of the footwear.
[0218] The lower end of the outer layer is preferably non-perforated by stitching. In other words, the footwear should not include a net stitched to the insole and the lower end of the outer layer.
[0219] By optional sole layers or members according to embodiments of the invention, should be understood as e.g. inlayers of different shape and material for the purpose of an optimized fit, softness, bouncing effect or similar to improve e.g. the fit or comfort of the footwear. Due to the construction of the footwear according to embodiments of the invention, additional waterproofing layers, such as e.g. a gasket, may not be needed as a further layer of the footwear and/or sole. In a preferred embodiment of the invention no additional gasket or member is applied for the purpose of making the transition between membrane material and insole waterproof as the waterproofness in this context preferable is provided by the sole material itself, e.g. PU applied to the upper, including the transition, during a direct injection or it may be provided by the cement or the cement combined with an outsole. In such a case, the cement is applied to the upper and the outsole during, including the transition, during the process of attaching the outsole to the upper by a cementing process.
[0220] A gasket-free approach to this waterproofness has several benefits including cost-saving in relation to manufacture and materials.
[0221] It is advantageously realized that the membrane should extend further than the outer layer at the lower end of the upper, as the desired attachment and stitching may thereby be made advantageously without perforating the part of the membrane which is overlapping the lower end of the outer layer.
[0222] By that the membrane is extending further should be understood as the membrane extends in one piece and not e.g. with an additional strip or ribbon that could be attached to the membrane. This also means that stitching is only applied in the membrane and no stitches are applied to the upper.
[0223] In an embodiment of the invention where the sole is cemented to the upper, a part of the adhesive by means of which the upper is cemented to the sole is pre-adhered to the sole and pre-adhered to the lower end of the outer layer. A further part is pre-adhered to the sole prior to the final gathering of the pre-adhered upper and the pre-adhered sole.
[0224] In an embodiment of the invention where the sole is cemented to the upper, a part of the adhesive by means of which the upper is cemented to the sole is pre-adhered to the sole and pre-adhered to both the lower end of the outer layer and the lower end of the membrane. A further part is pre-adhered to the sole prior to the final gathering of the pre-adhered upper and the pre-adhered sole.
[0225]
[0226]
[0227] The membrane is attached to an insole IS by stitching STI and the inner sock-like membrane stitched to the insole is then cemented or DIP'ed to the sole of the footwear.
[0228] A sole provided by a DIP process it typically made of polyurethane (PUR).
[0229] A sole applied in a cemented footwear may be molded or provided by a direct injection process and the subsequently in a separate step be cemented unto the upper.
[0230] Further and as illustrated in
[0231] The height of the anchoring adhesive AA as designated by DIST C in
[0232] The use of a maximum height DIST C of the anchoring adhesive makes the strobel sewing easier as the outer layer and membrane in combination is more flexible than a laminated outer layer/membrane and at the same time due to the fact that the insole is as large as possible thereby getting the insole circumference as close to the circumference of the lower edge of the outer layer LEOL as possible without bending the membrane.
[0233] Bending the membrane may have several disadvantages, such as excessive use of membrane but also resulting in a more difficult sealing or the lower end of the membrane to the sole.
[0234]
[0235] The curvature in the transition point of the cross-section should approximate the corresponding part of a wearer foot or this should at least apply to a large number of cross-sections of the transition around the circumference of the insole.
[0236] The approximated and illustrated curved should at least have a radius of 1 cm and less than 100 cm, such as a radius RAD of at least 1 cm and less than 80 cm, such as a radius RAD of at least 1 cm and less than 60 cm.
[0237] Furthermore, the insole should in the vertical direction at the midpoint of the insole as illustrated as RAD IS have radius RAD IS of at least 5 cm and less than 200 cm, such as a radius of at least 10 cm and less than 150 cm such as such as a radius of at least 10 cm and less than 150 cm.
[0238] It is clear from the illustration an explanation that the transition and the lower end of the membrane is easily accessible from below for the intended sealing of the membrane to the sole and at the same time the folding of membrane and/or insole is minimized thereby avoiding risks of water bridges through the intended sealing, in particular in relation to humidity/water transport via the outer layer towards the transition between the lower end of the membrane and the insole.
[0239]
[0240] Also illustrated in
Outer Layer
[0241] The outer layer may be a fabric/textile layer, a leather layer, a nubuck layer, a knitted layer, polymer, canvas, or any type of layer that may be used as the outermost layer of a footwear upper, where the other layer may provide the outer appearance of the footwear.
[0242] The outer layer may be outermost layer of the outer layer, however, the outer layer may also comprise other layers or treatments covering the other layer as an extra outer layer for e.g. strengthening, color, elasticity, stiffness, weight protection or aesthetical appearance.
Examples Leather
[0243] Examples of leather types that may be used within the scope of invention may be types such as full grain or top grain leather, embossed grain leather, suede and nubuck.
[0244] In principle, the leather can derive from any source, including cow hide, horse hide, goat skin, sheep skin, kangaroo hide, reptiles, fish and the like. Even so, preferably the leather is a mammal or marsupial leather (i.e. derives from a hide from a mammal such as a cow or horse, or a marsupial such as a kangaroo). Mammal leathers are most often used.
[0245] In terms of terminology, top grain surface is the upper portion or outer covering of the animal whereas split is the under layer which is removed by splitting operation in the leather making/tanning process.
[0246] Full grain refers to top grain leather where no sanding of the surface takes place. Nubuck leathers have the surface layer removed or modified typically by a buffing process. Although the leather still has the pronounced network of natural fibers and corium structure giving the leather strength, the very top grain surface is effectively removed. The buffing process used to form nubuck leathers leaves protein fibers that produce a velvet-like feel. Artificially embossing nubuck leather can create a surface texture, but often the embossing step damages the protein fibers and undermines the velvet-like feel. Split leather is created from the fibrous part of the hide left once the top-grain has been separated from the hide, e.g. to be used as full grain or top grain leather. Split grain leather may have reduced strength as compared to comparable thicknesses of top grain leather, as the fibers tend to be more aligned.
Membrane
[0247] The outer layer may be provided as a layer that may be liquid and/or vapor permeable, as any liquids that can pass the first layer, are prevented from entering the foot insertion volume by the breathable waterproof membrane.
[0248] In one or more embodiments the membrane may comprise a waterproof and vapor permeable functional layer. A waterproof and vapor permeable membrane including a a functional layer is well known within the art, such as commercially available GORE-TEX® laminate from W.L. Gore & Associates, Sympatex, Cosmo, Outdry, Covestro, Respilon, Schoeller or Wilhelm.
[0249] The membrane may comprise a single layer of material or may comprise two or more layers of materials that are provided in a laminate, creating a functional layer assembly. The membrane may be in the form of any layer, or a laminate of layers that create a waterproof and vapor permeable layer for the upper. The vapor permeability of the layer may be adjusted in accordance with the specific use of the footwear, so that for some uses the vapor permeability may be greater than other uses, such as a hiking boot versus a casual shoe.
[0250] Other layers to be included or attached to the membrane includes fabric on one or both sides of the membrane layer. Such layers may e.g. be included for strength purposes, layers or treatment on the membrane for reducing the surface tensions, layers for providing color and/or e.g. a lining. In the latter case a footwear lining may thus form a part of what is referred to in the description as membrane.
[0251] In one or more embodiments of the invention, the membrane may be a kind of textile fabric compounded with polymer waterproof breathable materials (PTFE) membrane) plus fabric. The membrane. The membrane may also be characterized as microporous membrane expanded Teflon (polytetrafluoroethylene) more formally known as ePTFE. that is e.g. provided in a thickness of about a 0.01 mm when not including the thickness of further laminated fabrics etc.
[0252] The waterproof membrane may comprise other layers and the thickness may depend on the applied layers. In some or more embodiments of the invention, the membrane may be e.g. 0.3 mm or 0.6 mm and in other applications such as e.g. a shoe suitable for cold weather, the membrane may e.g. be 2.5 mm or thicker.
[0253] The materials of the membrane layers may vary according to the application and relevance for use, wherein a thin and flexible membrane may be relevant for e.g. athletic shoes and membranes comprising e.g. wool or similar layers may be suitable for e.g. winter boots.
[0254] Breathable membrane, waterproof membrane, breathable waterproof membrane and membrane may be used interchangeably according to the invention.
Insole
[0255] The insole is the sole that binds the footwear upper to the rest of the footwear and the material of the insole depends on the type of footwear construction and materials may be woven, non-woven, fabric, textile, canvas, leather, membrane, PU and/or foam material and may comprise additional materials for comfort or functionality.
[0256] According to embodiments of the invention, the footwear manufacturing may also be made without an insole. In this case only edging and a cord “criss-cross” the sole and the method may also be termed as “string lasting”.
[0257] Insole and strobel sole may be used interchangeably according to the invention.
[0258] The insole may be stitched to the lower end of the membrane by a strobel stitching technique that may are made by a strobel stitching machine.
[0259] An example of a strobel stitching machine may e.g. be a Strobel 141-23 EV single thread overseaming machine. A needle type may e.g. be a needle type 134.
Adhesive
[0260] In embodiments of the invention, anchoring adhesive may be attached to a surface area of the membrane, and does not penetrate the membrane, either partly or fully. Thus, the water and vapor impermeability of the membrane is not affected by the adhesive. Thus, it may be important to ensure that the adhesive does not increase the water or vapor permeability of the membrane. The adhesive may provide a waterproof seal between the outer layer and the membrane of the upper.
[0261] In one or more embodiments the anchoring adhesive may extend from the lower end of the outer layer and extending along the outer layer of the total circumference of the lower end direction.
[0262] The anchoring adhesive may be an adhesive layer but may also be a weld joint, a melted joint, or any suitable adhesives that is capable of attaching and/or fixing the outer layer to the membrane.
[0263] The anchoring adhesive may be part of the outer and/or the membrane, e.g. where the outer layer may be melted to the membrane, or vice versa, or the layers may be melted to each other. Alternatively, the anchoring adhesive may be a separate member, that is positioned between the two layers, e.g. an adhesive layer.
[0264] In one or more embodiment the anchoring adhesive may extend continuously along the entire lower end of the membrane. The anchoring adhesive may be a waterproof sealing/adhesive that means that the adhesion is capable of preventing water to penetrate the foot insertion volume of the footwear.
[0265] The anchoring adhesive AA used for adhering the outer layer and membrane at the lower end as described according to the invention, may be any suitable adhesives.
[0266] Examples of anchoring adhesives may e.g. be, non-water-based adhesives, water-based adhesives, heat-activated adhesives, two-component adhesives, cold glue.
[0267] Examples of anchoring adhesives may e.g. be epoxies, methyl methacrylates, silicone adhesives, urethanes.
[0268] Examples of adhesives used according to the invention may be Locite Aquace W-01, Helmitin 11019 Helmitin GPV and/or Helmitin 49631.
[0269] The anchoring adhesive AA used according to the invention may be in various forms such as e.g. liquid, film, tape that may adhere on one or both sides.
[0270] According to embodiments of the invention, the adhesive may be present in a continuous layer or be present as a “perforated” or non-continues adhesive layer facilitating both sufficient bonding but also breathing or some kind of moisture transport through the layers.
[0271] The application of adhesive to the leather parts may be in the form of a prelamination.
[0272] According to embodiments of the invention, hot melt adhesive or hot melt glue is used to attach the sole to the upper.
Assembly
[0273] After the strobel stitching, the upper is drawn over a last LA that may be specially designed for the footwear. To make the upper flexible prior to lasting, the upper may be treated first with e.g. steaming. The treatment makes the upper easier to last and prevents the upper material from tearing.
[0274] To ensure that the sole material binds efficiently to the upper, the upper may first be roughed or scratched at the lower end of the outer layer.
LIST
[0275] FW Footwear [0276] U Upper [0277] S Sole [0278] OS Outsole [0279] FIV Foot insertion volume [0280] OL Outer layer [0281] MEM Membrane [0282] OSF Outer layer surface facing the foot insertion volume [0283] OSO Outer layer surface facing outward [0284] BSF Membrane surface facing the foot insertion volume [0285] BSO Membrane surface facing the outer surface OSF [0286] UP Upper part [0287] LP Lower part [0288] UFS Upper facing surface of the sole [0289] SUE Sole upper edge [0290] GCS Sole ground contacting surface [0291] LOL Outer layer lower end [0292] LMEM Lower end membrane [0293] AA Anchoring adhesive [0294] IP Injection perforation [0295] MFD Lateral distance [0296] STI Stitching [0297] IS Insole [0298] LA Last [0299] AC Adhesive cement [0300] TC Toe cap [0301] TEND Toe end [0302] HC Heel cap [0303] HEND Heel end [0304] DSA Double sided adhesive [0305] SEC1 Section 1 [0306] SEC2 Section 2 [0307] TH Thread [0308] L Length [0309] W Width [0310] STFD Stitch free distance [0311] MA Marks [0312] MFD Mark free distance [0313] FAD First adhesive [0314] SAD Second adhesive [0315] TAD Third adhesive [0316] WBS Waterproof bottom sealing [0317] RM Reinforcing member [0318] LEND Lower end [0319] ATTA Attachment arrangement [0320] UINA Upper intermediate area [0321] TOL Outer layer top [0322] IOL Outer layer intermediate layer [0323] LIN Lining material [0324] BAC Backing material [0325] FUN Functional layer [0326] AIR Space [0327] LAC lower anchoring adhesive circumference [0328] TE Top edge [0329] UC Upper circumference [0330] UTEND Upper top end [0331] ULEND Upper lower end