Breathable shoe

Description

Technical Field [0001] The present invention relates to a method for making a breathable shoe.

Background Art [0002] It is known that a shoe, in order to be comfort-able, must ensure proper exchange of heat and water vapor between the microclimate inside the shoe and the external one.

[0003] This exchange of heat and water vapor, how-ever, must not compromise in any way the impermeableness of the shoe to external humidity or water.

[0004] Currently commercially available shoes entrust this exchange of heat and water vapor substantially to the upper or to the sole.

[0005] As regards the upper, shoes which are perforated and/or provided with linings made of a breathable and waterproof material are currently commercially available.

[0006] In some models, some parts of the upper can be replaced with materials which are indeed waterproof and breathable at the same time.

[0007] In rubber soles, many solutions have been proposed in order to solve the problem of the lack of breathability which is inherent in the characteristics of the material.

[0008] One of these solutions, disclosed in Italian patent No. 1232798, consists in dividing the sole into two layers with through holes and in interposing a breathable waterproof membrane which is joined perimetrically and hermetically to the two layers.

[0009] Variations of this solution occur in subsequent patents, all of which are in any case focused on dividing the sole into two layers in order to stop external water and dirt in a region which is as close as possible to the surface that makes contact with the ground.

[0010] This entails manufacturing complications and in particular prevents the provision of particularly thin soles.

[0011] In othercases, such asforexample in European patent No. 275644, the entire sole is provided with through holes and is joined at the top with an upper having a bottom surface, which is entirely made of a waterproof breathable material (film of polytetrafluoroethylene porous foam) with the interposition of a protective layer made of porous material.

[0012] This structure is adapted for shoes whose upper is not provided with the classic methods, such as the ones known as "Strobel", ''ideal welt" or "pre-assem-bled".

[0013] European patent No. 103601 also discloses a sole in which delimited regions are completely crossed through their thickness by holes and in which, in an upward region, a waterproof and breathable membrane is in contact with a substrate made of soft perforated material on which the foot rests; this solution is substantially equivalent to the preceding one and makes it impossible to apply classic methods.

[0014] The sole is monolithic with the upper and the entire assembly is made of plastic and is therefore not breathable.

[0015] The regions with holes are separate from the rest and are constituted by removable disks.

[0016] Substantially the same situation is proposed by French patent No. 1228239, which discloses a shoe with a sole and an upper made of the same waterproof but non-breathable (plastic) material, provided with through holes (in both the sole and the upper) and, inside the upper, a bootie made of waterproof and breathable material.

[0017] WO97/1436 discloses a vapor-permeable shoe which belongs to the instant category.

Disclosure of The invention [0018] The aim of the present invention is to provide a method for manufacturing a shoe with a waterproof and breathable sole which is simpler than the ones known in the state of the art.

[0019] Within this aim, an object of the present invention is to provide a method for manufacturing a breathable shoe whose structure entails absolutely no constraints as regards styling and aesthetic research, allowing the greatest freedom to shoe shapes and types. [0020] Another object of the present invention is to provide a method for manufacturing a breathable shoe which is meant for both day-to-day use and for sports use.

[0021] Another object of the present invention is to provide a method for manufacturing a breathable shoe whose cost is competitive with respect to the costs of known shoes.

[0022] In accordance with The invention, there is provided a a method for manufacturing a breathable shoe as defined in the appended claims.

Brief Description of the Drawings [0023] Further characteristics and advantages of the present invention will become better apparent from the descriptionofthree embodimentsthereof, illustratedon-ly by way of non-limitative example in the accompanying drawings, wherein:

Figure 1 is a cross-section view of a shoe according to The invention in the assembled condition, in a first embodiment;

Figure 2 is a cross-section view of the shoe of Figure 1 prior to final assembly;

Figure 3 is a cross-section viewof the sole of a shoe according to The invention in a second embodiment thereof;

Figure 4 is a cross-section view of a shoe according to The invention in the assembled condition, in a third embodiment thereof;

Figure 5 is a cross-section view of the shoe of Figure 4 prior to final assembly;

Ways of carrying out The invention [0024] With particular reference to Figures 1 and 2, a breathable shoe manufactured according to The invention comprises, in this case, an assembly 10 which wraps around the foot insertion region and is in turn composed of an upper 11 which is breathable (for example made of natural leather without sealing pigments) and is associated with a breathable or perforated lining 12 (made for example of Cambrelle).

[0025] The lining 12 is associated with the upper 11 by spot-gluing, so as to not compromise breathability through said upper.

[0026] The assembly 10 furthermore comprises a breathable or perforated insole 13 which is joined, by means of stitched seams 13a, to the edges of said upper 11 according to the manufacturing method commonly known as "Strober or "ideal welt", so as to form a sack into which the assembly last, not shown in the figures, is to be inserted.

[0027] The insole 13 can be made of a material which is breathable (for example natural leather) or perforated, with an optional heel seat lining made of soft leather with absorbent rubber latex.

[0028] A membrane 14 made of a breathable and waterproof material, optionally coupled (so as to withstand hydrolysis without compromising breathability) to a supporting mesh 15 made of synthetic material, is associated with said insole 13 for example by spot gluing.

[0029] Preferably, the mesh 15 lies below the membrane 14.

[0030] The membrane 14 can be of the type that is commercially available and commonly known by the trade-name Gore-Tex.

[0031] A sole 16, formed by a single block of elastomer with through holes 16a through its thickness, is joined to said upper for example by gluing (with hydrolysis-resistant adhesives) or high-frequency welding along a perimetric band and is sealed perimetrically with respect to said membrane 14.

[0032] As an altemative, direct injection of the sole 16 on the upper 11 can be provided.

[0033] A protective element 17 made of a material which is hydrolysis-resistant, water-repellent, breathable or perforated is associated below said membrane 14 by spot gluing; for example by adopting a commercially available adhesive which is resistant to hydrolysis (of the kind commonly known as "hot-melt" or calend-ered-powder systems).

[0034] The protective element 17 can be conveniently made of a material which is water-repellent and capable of drying rapidly, such as for example nonwoven fabric or needled cloth.

[0035] As an alternative, it is possible to provide a Kevlar or filtering fabric.

[0036] Conveniently, the edge 18 of the protective element 17 lies inside the edge 19 of the membrane 14 in order to allows to form a seal with the sole 16.

[0037] As an alternative, the edge 19 of the membrane 14 can be folded around the edge 18 of the protective element 17, or said protective element could be thinned at the edge (if it has the same perimeter as the membrane 14) so as to allow the penetration of the sealing adhesive between the membrane 14 and the sole 16.

[0038] The protective element 17 protects the membrane 14 from external impacts or foreign objects which might penetrate through the holes provided in the sole 16.

[0039] A breathable or perforated inner sole 20 completes the shoe.

[0040] The shoe is manufactured by associating the membrane 14 and the protective element 17 with the assembly 10, which is constituted by the upper 11 and the insole 13 (fitted on the last), and subsequentlyjoin-ing the sole 16.

[0041] The shoe according to The invention, as shown by the description of this first embodiment, is entirely breathable, any non-breathable regions being limited substantially to the perimetric regions of the sole, which must in any case ensure a good seal with respect to external moisture and water.

[0042] With particular reference to Figure 3, a shoe according to The invention, in a second embodiment, differs frorn the preceding cases in that the sole, now designated by the reference numeral 216, has in its upper part a hollow region 220 which is delimited perimetrically by a border 221.

[0043] Dome-shaped protrusions 222 protrude from said hollow region 220, are uniformly distributed and advantageously reach the same height as said border 221. [0044] Holes 223 or channels are provided in said border and connect the region 220 to the outside.

[0045] Each one of said holes 223 is inclined with respect to the ground contact plane, so that the outward part is lower than the inward part (this is done to avoid stagnation).

[0046] The holes 223 can furthermore be provided with one-way valves, not shown in the figures (which allow only air to flow outward).

[0047] With particular reference to Figures 4 and 5, a breathable shoe according to The invention, in a third embodiment, comprises in this case an assembly 310 composed of a tubular upper 311 which is breathable (for example made of natural leather without sealing pigments) which is associated with a breathable or perforated lining 312 (made for example of Cambrelle).

[0048] The lining 312 is associated with the upper 311 by spot gluing, so as to not compromise breathability through said upper.

[0049] A membrane 314 made of breathable and waterproof material, optionally coupled (so as to withstand hydrolysis without compromising breathability) to a supporting mesh 315 made of synthetic material, is associated with the lower part of the upper 311, for example by spot gluing.

[0050] Asole 316 madeof a single blockof elastomer with through holes 316a through its thickness is joined to said upper 311, for example by gluing (with hydrolysis-resistant adhesives) or high-frequency welding along a perimetric band and is sealed perimetrically to said membrane 314.

[0051] As an alternative, it is possible to provide for the direct injection of the sole 316 over the upper 311.

[0052] A protective element 317 made of a material which is resistant to hydrolysis, water-repellent, breathable or perforated is associated below said membrane 314 by spot gluing, for example by adopting a commercially available adhesive which is resistant to hydrolysis (of the type commonly known as "hot-melt" or calend-ered-powder systems).

[0053] Conveniently, the edge 318 of the protective element 317 is internal to the edge 319 of the membrane 314 in order to allow to form a seal with the sole 316.

[0054] As an alternative, the edge 319 of the membrane 314 can be folded around the edge 318 of the protective element 317 or said protective element could be thinned at its edge (if it has the same perimeter as the membrane 314) until it allows the sealing adhesive to penetrate between the membrane 314 and the sole 316.

[0055] The protective element 317 protects the membrane 314 against external impacts or foreign objects which might penetrate through the holes provided in the sole 316.

[0056] In another alternative, the sole 316 can be provided as in the second embodiment.

[0057] The shoe is manufactured by associating the membrane 314 and the protective element 317 with the assembly 310, which is fitted on the last, and subsequently joining the sole 316.

[0058] In practice it has been observed that the present invention has achieved its intended aim and objects.

[0059] A manufacturing method for a shoe with a waterproof and breathable sole has in fact been provided by using the "Strobel", "ideal welt", "pre-assembled" and otherclassic methods (modified appropriately) in a simpler manner than shoes known in the state of the art.

[0060] It should also be observed that the shoe manufactured according to The invention perfectly fulfills the need to have optimum exchange of heat and water vapor between the internal microclimate and the external one, while maintaining a complete impermeableness to water and moisture.

[0061] It is observed that all this has been achieved while maintaining a shoe structure which is highly flexible and adaptable to any type of styling and to any aesthetic and economical level required by the market. [0062] It is also observed that the structure of the shoe manufactured according to The invention can be easily mass-produced, since the operations can be fully automated.

[0063] It is further observed that the structure of the shoe manufactured according to The invention allows a certain flexibility as regards the association of its com-ponents, thus leading to considerable production savings in relation to its f lexibi I ity and adaptability to the various manufacturing situatíons and conditions.