BREATHABLE OUTSOLE FOR FOOTWEAR AND FOOTWEAR WITH THIS BREATHABLE OUTSOLE

Description

Field of the Invention

[0001] In its most general aspect the present invention refers to the technical field of footwear items and in particular concerns a breathable outsole for footwear and footwear comprising the aforesaid breathable outsole.State of the art

[0002] Today, breathable outsoles for footwear and footwear provided with such outsoles are known, the breathable outsoles being provided with openings adapted to improve foot ventilation.

[0003] Document US 4,813,160, for example, describes footwear comprising a midsole and a plurality of tubes transversely arranged in the midsole, wherein the tubes are equipped with open ends facing onto opposite side surfaces of the midsole, thereby defining openings that face onto the environment outside the footwear. In detail, the tubes are in communication with the inside of the footwear through ducts that are substantially perpendicular to the foot-shoe contact plane and allow hot air and sweat produced inside the footwear to be ejected outside the footwear itself.

[0004] Patent application WO 2006 / 016095 A2 describes footwear with an outsole structure consisting of a semi-finished product that contains a plurality of tubes arranged transversely to the longitudinal axis of the foot and that is overlaid with a supporting layer. The supporting layer is provided with openings substantially perpendicular to the foot-shoe contact plane and in communication with the ducts of the semi-finished product, the openings creating paths for the air coming out of the inside of the footwear towards the outside environment.

[0005] Disadvantageously, according to the above solutions, first the ducts or the semi-finished product have to be produced and then either the ducts or the semi-finished product equipped with the ducts have to be inserted in the midsole and, as a result, the related process is complex and expensive.

[0006] Patent application WO 2014 / 011164 A1 describes footwear comprising an outsole consisting of a midsole and a tread, in which the midsole is provided with ventilation holes that communicate the surface contacting the foot with the ventilation channels located below, which are between the midsole and the tread. The ventilation channels form, on the side wall of the outsole, openings that are flared outwards, the openings being, furthermore, in communication with the ventilation holes placed on the tread. Such a solution, disadvantageously, is particularly vulnerable to infiltrations of water and impurities in the footwear, the aforesaid channels being extremely exposed to, and accessible by, the agents outside the footwear, such as rainwater, puddle water, mud, gravel, crushed stone, residues of various kinds, etc.

[0007] Patent EP 1 089 642 B1, in the name of the same applicant, describes a breathable and also waterproof outsole, which includes an upper element and a lower element, wherein the lower element has a hollow region in its top part delimited by an edge provided with ventilation openings that extend radially and connect the hollow region with the environment outside the footwear, wherein the ventilation openings are determined by hermetically joining the upper element with the lower element. The lower element further has through-openings along a mainly vertical direction with respect to the foot-shoe contact plane, and a waterproof and breathable membrane is placed between the upper and lower elements, in order to prevent water from entering the footwear. Although this solution is advantageous, it suffers from some drawbacks, among which poor comfort and poor footwear stability. In fact, the above said hollow region, although being equipped with reliefs adapted to contain its collapse, was found to be uncomfortable during the use of the footwear because, by opposing limited resistance to the weight of the user, it induces a feeling of foot sinking that, as mentioned, gives rise to discomfort and instability. Furthermore, the hollow region forms an air chamber that leaves uncovered a large part of the membrane, which is therefore considerably exposed to contact with impurities and / or water that can enter through the ventilation openings and come into contact with the membrane itself, thus damaging it.

[0008] US 2017 / 127751 A1 discloses a ventilated shoe comprising a bottom pad and a ventilation pad, in which the bottom pad is provided with a peripheral wall that has a front part, a rear part, a right side part and a left side part, wherein a plurality of right and left side holes are formed in the right and left side parts of the peripheral wall, in which the ventilation pad, that is disposed on the bottom pad to be surrounded by the peripheral wall, in a wave-like layer with alternate crests and troughs, forms a plurality of tunnel vaults each of which extends from the right side part to the left side part, in which a right belt and a left belt are disposed on the right and left side parts of the peripheral wall to be slidable between two positions.

[0009] Document WO 2014 / 157773 A1 describes a ventilated sole for a shoe comprising a sole placed on the lower part of a shoe and having an accommodation portion a groove in the front inner side of the upper surface thereof, and having side holes punched from an inner wall surface of the accommodation portion to an outermost edge side; and a ventilated pad inserted into the accommodation portion and having a corrugated air paths in an upper direction on the lower surface thereof, and having punched air holes vertically penetrated on the upper surface of the air paths.

[0010] Document KR 101 433 355 B1 describes a midsole for trekking shoe, which is composed of a main body and a cover, wherein the main body has a first through-hole formed at a side thereof, and the cover for covering a top surface of the main body has a second through-hole and protrusion thereon, so as to enhance breathability and cushioning ability, in which the top surface of the main body, that is, a surface contacting the protrusion of the cover, is configured to have a gentle convex shape, and the protrusion is arranged to have a concave shape corresponding to the shape of the top surface, so that foreign substances which are unavoidably introduced may be guided to flow into a side of the midsole, and in which when the main body and the cover are coupled, a seat is formed along an edge of a portion where the main body and the cover are coupled, allowing the cover to be supported by the seat, so that the cover can be prevented from sinking even in long-time walking and the protrusion and an air path can be prevented from being damaged, and wherein the first through-hole formed at the side of the main body is finished by using a mesh membrane to prevent various foreign substances from being introduced in advance.

[0011] Document US 2007 / 011907 A1 discloses a vapor-permeable and waterproof sole for open shoes such as sandals, sabots and the like, comprising a lower element, an upper element and a membrane, in which on the lower element a tread is integrated in a downward region, in which the lower element is chosen between an element that is vapor-permeable at least in an upward region and a perforated element, in which the upper element is vapor-permeable and / or perforated element, in which the membrane, that is vapor-permeable and waterproof, is interposed between the lower element and the upper element, in which the membrane and the lower element and the upper element are joined hermetically in the perimetric regions of mutual contact, and in which at least one vapor-permeable comfort layer, which composes the lower element and / or the upper element and is made of three-dimensional fabric, forms a ventilation gap.Summary of the invention

[0012] The technical problem underlying this invention was to provide a breathable outsole for footwear with structural and functional characteristics able to overcome one or more of the drawbacks mentioned above with reference to the known art.

[0013] The aforesaid problem is solved by a breathable outsole according to independent claim 1. Additional embodiments are defined in the dependent claims.

[0014] In practice, in the aforesaid outsole the midsole is partially contained sideways between the side walls of the tread, which are equipped with through-holes that are in communication with the grooves of the midsole, so as to obtain, by coupling the midsole and the tread, channels for expelling sideways sweat in vapor phase from the inside of footwear, the aforesaid outsole is intended for, towards the environment outside the footwear itself.

[0015] Advantageously, side walls of the tread that, in a manner of speaking, climb the midsole, i.e. overlap it, protect the ends or mouths of the aforesaid channels from the possibility of bumping into external objects. In this regard, it should be said that the aforesaid midsole is preferably made of a lightweight polymeric material to limit its weight, such as polyurethane foam (PU) or ethylene-vinyl acetate (EVA), whose abrasion resistance is limited, while the aforesaid tread is preferably made of a polymeric material provided with greater abrasion-resistance, such as rubber, thermoplastic polyurethane (TPU) or thermoplastic rubber (TR), to better resist prolonged contact with the ground to which it is subjected. The effect of abrasion on materials, such as for example PU or EVA, not only affects the appearance thereof, but also exposes them to faster degradation due to atmospheric agents, thereby shortening the useful life of the outsole and therefore of the respective footwear.

[0016] A further advantage of the present invention is that, unlike the known art mentioned above, neither is required to make tubes nor to obtain tubular cavities in the midsole for housing the tubes, so that the midsole itself and therefore the present outsole are made in a considerably simplified way.

[0017] Advantageously, it is still not necessary to use semi-finished products to define outlet paths for sweat in the vapor phase, because according to the present invention these outlet paths are formed by the aforesaid channels thanks to the aforesaid plurality of grooves that are made in one piece in the midsole, with significant simplification of the production process of the outsole according to the present invention and overall cost reduction.

[0018] Still advantageously, the aforesaid channels, being mainly occupied by air, provide a high degree of dampening and shock absorption in a substantially uniform manner throughout the entire outsole, i.e. along the entire plantar portion of a user's foot, thus avoiding unpleasant feelings of yielding or collapse.

[0019] Preferably, the aforesaid through-holes of the aforesaid first plurality of through-holes of the tread have a section smaller than the section of the aforesaid grooves at respective end portions proximal to the aforesaid side walls.

[0020] Preferably, the aforesaid side walls are tilted with respect to the aforesaid contact portion with the ground by an angle between about 90° and about 160°, more preferably an angle between 95° and 120°.

[0021] Preferably the aforesaid side walls have a concave outer profile.

[0022] Preferably, the aforesaid tread has an upper side facing the aforesaid midsole having a convex transverse profile at least next to the aforesaid grooves.

[0023] Preferably, the aforesaid lower side of the aforesaid midsole has a concave transverse profile at least next to the aforesaid grooves.

[0024] Preferably, the aforesaid contact portion with the ground of the aforesaid tread has a length smaller than the length of the aforesaid midsole, the aforesaid midsole having a first contact portion with the ground and a second contact portion with the ground at the forefoot and, respectively, at the hindfoot of the aforesaid outsole.

[0025] Preferably, the aforesaid midsole comprises an upper side opposing to the aforesaid lower side, wherein the aforesaid upper side is provided with a seat, the through-holes of the aforesaid first plurality of through-holes of the midsole facing onto the seat.

[0026] In practice, the aforesaid seat is a recess having predetermined limited depth and obtained on the aforesaid upper side of the aforesaid midsole.

[0027] Preferably, the aforesaid grooves of the aforesaid midsole have a wavy pattern.

[0028] Preferably, the aforesaid contact portion with the ground of the aforesaid tread has a lower side with a plurality of protrusions, wherein the protrusions of the aforesaid plurality of protrusions are preferably arranged in rows, wherein the aforesaid rows preferably have a wavy pattern.

[0029] Preferably, the aforementioned tread comprises a second plurality of through-holes, wherein the through-holes of the aforesaid second plurality of through-holes crosses the aforesaid contact portion with the ground of the tread.

[0030] Preferably, the aforementioned through-holes of the aforesaid second plurality of through-holes of the tread face onto the aforesaid grooves of the aforesaid midsole and, more preferably, the aforesaid through-holes of the aforesaid second plurality of through-holes of the tread are substantially aligned with the aforesaid through-holes of the aforesaid first plurality of through-holes of the midsole.

[0031] According to the above, the aforesaid through-holes of the aforesaid second plurality of through-holes of the tread may be provided between rows of protrusions, or between protrusions of the same row or even at protrusions, in the latter case the aforesaid contact portion with the ground of the tread having, next to at least a percentage of the protrusions, respective round recesses, in practice dome-shaped cavities, the aforesaid through-holes of the aforesaid second plurality of through-holes of the tread facing onto the round recesses.

[0032] Preferably, the aforesaid upper side of the aforesaid tread has a profile that corresponds to the profile of the aforesaid lower side of the aforesaid tread, and more preferably, the aforesaid upper side of the aforesaid tread and the aforesaid lower side of the aforesaid midsole match each other, i.e. they are complementary to one another.

[0033] Preferably, the aforesaid midsole comprises a layer of waterproof and breathable material sealed, so as to be waterproof, to the aforesaid midsole, inside the aforesaid seat arranged on the aforesaid upper side of the midsole.

[0034] Preferably, the aforesaid outsole comprises at least one protective, more preferably breathable, layer consisting of a fabric or a knit made of synthetic material, which is constrained to the aforesaid midsole inside the aforesaid seat arranged on the aforesaid upper side of the midsole.

[0035] According to the above, the aforesaid problem is further solved by footwear comprising the aforesaid outsole and an upper constrained to the aforesaid outsole.DEFINITIONS

[0036] The water-vapor permeability is determined according to the method set out in chapter 6.6 of the regulation ISO 20344-2004, which is referred to herein and which should be considered as reference.

[0037] Specifically, the regulation ISO 20344-2004, in chapter 6.6 "Determination of water-vapor permeability", relating to safety footwear, describes a testing method consisting of fixing a specimen of the material to be tested so as to close the opening of a bottle containing a certain amount of solid desiccant, i.e. silica gel. The bottle is subjected to a strong airflow under conditioned atmosphere. The bottle is rotated so as to mix the solid desiccant and optimize the drying action of the air contained in the bottle. The bottle is weighed before and after the test period to determine the mass of moisture that has passed through the material and has been absorbed by the solid desiccant. The water-vapor permeability, expressed in milligrams per square centimeter per hour [mg / cm 2< *h], is then calculated on the basis of the measured mass of moisture, the area of the bottle opening, and the test time.

[0038] In the scope of the present invention, the expressions "permeable to vapor", "permeable to water vapor" and "breathable" have the same meaning and are used as alternatives to one another.BRIEF DESCRIPTION OF THE FIGURES

[0039] Further characteristics and advantages of the invention will be better highlighted by considering the following detailed description of some preferred, but not exclusive, embodiments illustrated by way of example only and without limitations, with the aid of the accompanying drawings, in which: figure 1 shows a bottom view of a breathable outsole for footwear, comprising a midsole and a tread constrained to one another, wherein the midsole comprises a plurality of grooves with wavy pattern on a lower side facing the tread, according to the present invention; figure 2 shows a side view of the outsole of figure 1; figure 3 shows a longitudinal section view of the outsole of figure 1, combined with an upper T only partially shown; figure 4 shows a cross-sectional view of the outsole of figure 1, along a plane passing through one of the aforesaid grooves and having a wavy pattern as the aforesaid grooves; figures 5 and 6 show the midsole of the outsole of figure 1, separated from the aforesaid tread, according to upper and lower views, respectively; figure 7 shows a side view of the outsole of figure 1, combined with an upper T' for making footwear according to an embodiment variation of the present invention; figure 8 shows a cross-sectional view of the outsole of figure 1, along a plane passing through one of the aforesaid grooves, according to a further embodiment variation of the present invention. Detailed description of the invention

[0040] Referring to figures 1-6, a breathable outsole for footwear is depicted by the numeral 1 on the whole.

[0041] The outsole 1 basically comprises a midsole 2 and a tread 3 constrained to one another, for example by adhesives means, wherein both the midsole 2 and the tread 3 comprise respective first pluralities of through-holes.

[0042] In particular, according to the invention, the midsole 2 comprises a lower side 4 facing the tread 3 that has a plurality of grooves 5, the through-holes of the first plurality of through-holes of the midsole 2, depicted by the numeral 6, facing onto the grooves.

[0043] Still according to the invention, the tread 3 comprises a contact portion with the ground, depicted by the numeral 7, and side walls 8 that extend from the contact portion with the ground 7 and partially overlap the midsole 2 sideways and on which the through-holes of the first plurality of through-holes of the tread 3, depicted by the numeral 9, are arranged.

[0044] Again according to the invention, it has to be said that the through-holes 9 of the first plurality of through-holes of the tread 3 at least partially intercept the grooves 5 of the midsole 2.

[0045] This way, side outlets, i.e. in practice channels, are advantageously created for expelling sweat in the vapor phase from the inside of footwear, this outsole is designed for, towards the environment outside the footwear itself, as depicted by the arrows in the example of figure 4.

[0046] Still according to the invention, it has to be said that the through-holes 9 of the first plurality of through-holes of the tread 3 have a section smaller than the section of the grooves 5 at respective end portions of the grooves 5 proximal to the side walls 8 of the tread 3.

[0047] Due to the section reduction of the aforesaid channels near the side walls of the tread, advantageously the speeds of air and water vapor coming out of the outsole locally increase (Pitot effect), thus making the ventilation in the footwear more effective. Furthermore, the aforesaid section reduction is advantageous because it reduces the risk of foreign objects entering the same side outlets, while at the same time allowing the section to be increased in the remaining portion of the channels so as to maximize the weight reduction of the midsole and make the latter more flexible.

[0048] According to the invention, the side walls 8 of the tread 3 form an angle between about 90° and about 160° with the contact portion with the ground 7 of the tread 3 itself, and according to the example of figures 1-6, the side walls 8 are tilted with respect to the contact portion with the ground 7 by an angle slightly greater than 90°, for example 95°, while a beveled portion of the tread 3 is preferably provided where the side walls 8 and the contact portion with the ground 7 join each other.

[0049] Still with regard to the contact portion with the ground 7 of the tread 3, it has to be said that it preferably comprises a plurality of protrusions or jutting portions made in one piece with the tread 3 and depicted by the numeral 10, which according to the example of figures 1-6 are arranged in rows transversally extending on a lower side 11 of the contact portion with the ground 7 of the tread 3, but it is also possible to provide a plurality of rows of protrusions or jutting portions and a plurality of protrusions or jutting portions arranged on a same row of the aforementioned rows of protrusions or jutting portions, in the latter case the protrusions or jutting portions constituting a sort of tread cleats. However, it has to be said that the rows of protrusions or jutting portions preferably have a wavy pattern.

[0050] If footwear including the outsole according to the present invention is used to walk on a wet or anyway slippery surface, a wavy geometry of the arrangement of protrusions or jutting portions is particularly advantageous as it allows greater adhesion and greater water drainage.

[0051] According to the invention and to the example of figures 1-6, the tread 3 further comprises a second plurality of through-holes depicted by the numeral 12, in which the through-holes 12 of the second plurality of through-holes of the tread 3 cross the contact portion with the ground 7 of the tread 3 itself.

[0052] In this regard, it has to be said that the through-holes 12 of the second plurality of through-holes of the tread 3 face onto the grooves 5 of the midsole 2 and preferably are substantially aligned with the through-holes 6 of the first plurality of through-holes of the midsole 2.

[0053] This way, a further outlet is advantageously created for expelling sweat in the vapor phase from the inside of footwear, this outsole is designed for, towards the environment outside the footwear itself, again as depicted by the arrow in the example of figure 4.

[0054] Moreover, preferably the contact portion with the ground 7 of the tread 3 has a length smaller than the length of the midsole 2, the latter having, as a result, a first contact portion with the ground 13 and a second contact portion with the ground 14 at the forefoot and, respectively, at the hindfoot of the outsole 1. This, according to the above, allows a further reduction of the weight of the outsole 1 according to the present invention.

[0055] In relation to the midsole 2, it has again to be noted that it comprises an upper side 15 opposing to the lower side 4 which is preferably provided with a seat 16, the through-holes 6 of the first plurality of through-holes of the midsole 2 facing onto the seat.

[0056] At the seat 16 that, in a manner of speaking, is practically dug into the upper side of the midsole 2 and particularly inside the seat 16, the outsole 1 may comprise a layer of waterproof and breathable material that is sealed, so as to be waterproof, to the midsole 2, the layer not being shown in the figures.

[0057] The layer of waterproof and breathable material is in practice a membrane of known type adapted to prevent water or foreign bodies from entering through the through-holes 6 of the first plurality of through-holes of the midsole 2.

[0058] As an alternative or in addition to the aforesaid layer of waterproof and breathable material, the outsole may comprise, still inside the seat 16, one or more protective layers, preferably also breathable, consisting for example of a fabric or a knit made of synthetic material, which are adapted to prevent water or other impurities from reaching the upper surface of midsole 2, i.e. the upper side 15 of the midsole 2, and then also from reaching the inside of footwear equipped with an outsole according to the present disclosure.

[0059] It should be noted that the aforesaid protective layers as well as the layer of waterproof and breathable material, if any, would be possibly exposed to the action of impurities and water only at the through-holes 6 of the first plurality of through-holes of the midsole 2, so that, as a result, the risk of their breakage or damage is reduced.

[0060] Still as regards the midsole 2 it has to be said that, according to the invention and according to the example of figures 1-6, the grooves 5 have a transverse wavy pattern, which advantageously recalls the wavy geometry of the rows of protrusions or jutting elements provided on the lower side 11 of the above-described contact portion with the ground 7 of the tread 3.

[0061] In this regard, it has to be said that the tread 3 comprises an upper side 17 having a profile substantially corresponding to the profile of the opposite lower side 11 of the same tread 3 and, moreover, preferably the upper side 17 of the tread 3 matches, i.e. is complementary to, the lower side 4 of the midsole 2, as shown in the example of figure 3 in which the outsole 1 is shown combined with a partially illustrated upper T, during the production of footwear according to the present invention.

[0062] It should be added that the grooves 5 extend transversely and preferably continuously on the lower side 4 of the midsole 2 from side to side, whereas the through-holes 9 of the first plurality of through-holes of the tread 3, according to the example of figures 1-6, are arranged on the side walls 8 so as to be substantially staggered with respect to the rows of protrusions 10.

[0063] In this regard, it has to be said that according to an embodiment variation of the present invention shown in the example of figure 7, which illustrates a breathable outsole 1' comprising a midsole 2' and a tread 3', through-holes 9' of the first plurality of through-holes of the tread 3' can be arranged on side walls 8' of the tread, so as to be substantially aligned with rows of protrusions or jutting portions made in one piece with the tread 3'.

[0064] In particular, in this embodiment, protrusion rows still having wavy pattern are provided, in which each row comprises a plurality of protrusions 10', in practice a plurality of cleats as previously revealed.

[0065] In this case, in the outsole 1', considering a given row of protrusions 10', through-holes of a second plurality of through-holes of the tread 3' are arranged alternately with the protrusions 10' of that given row of protrusions, so as to face onto a respective groove of the midsole 2'.

[0066] In the example of figure 7 the outsole 1' is shown combined with an upper T' thus making footwear 100' according to the present invention.

[0067] Therefore, unless otherwise specified, as regards the other characteristics of the outsole 1', what set forth above for the outsole 1 illustrated with reference to the example of the figures 1-6, remains valid and should be considered as reference.

[0068] In the example of figure 8 a further embodiment variation is depicted and, in particular, a breathable sole 1" comprising a midsole 2" and a tread 3" constrained to one another is shown, in which both the midsole 2" and the tread 3" comprise respective first pluralities of through-holes, in which the midsole 2" comprises a lower side 4" facing the tread 3" that has a plurality of grooves 5", the through-holes, depicted by the numeral 6", of the first plurality of through-holes of the midsole facing the grooves, in which the tread 3" comprises a contact portion with the ground 7" and side walls 8" that extend from the contact portion with the ground 7" and partially overlap the midsole 2" sideways and on which the through-holes are arranged, depicted by the numeral 9", of the first plurality of through-holes of the tread 3", and in which the through-holes 9" of the first plurality of through-holes of the tread 3" at least partially intercept the grooves 5" of the midsole 2".

[0069] This way, similarly to the above described embodiments to which reference is made, side outlets are obtained, in practice channels, for expelling sweat in the vapor phase from the inside of footwear, this outsole is designed for, towards the environment outside the footwear itself.

[0070] In detail, in the outsole 1", the aforesaid channels are made with a so-called "horseback" shape, i.e. the channels have a downward-tilted development with respect to the lying position on the ground.

[0071] For this purpose, the tread 3" has an upper side 17" facing the midsole 2" with a convex transverse profile at least next to the grooves 5" of the midsole 2".

[0072] Preferably, moreover, the lower side 4" of the midsole 2" has a concave transversal profile at least next to the grooves 5".

[0073] This way, according to the above, the outflow by gravity of any liquid seeped through the through-holes 9" of the first plurality of through-holes of the tread 3" is facilitated.

[0074] According to the invention the tread 3" also comprises a second plurality of through-holes depicted by the numeral 12", in which the through-holes 12" of the second plurality of through-holes of the tread 3" cross the contact portion with the ground 7" of the tread 3" and face onto the grooves 5" of the midsole 2".

[0075] In addition, a plurality of protrusions depicted by the numeral 10", are provided and are preferably arranged in rows of protrusions. In this regard, transverse rows of protrusions having wavy pattern, i.e. one wavy protrusion for row, in practice a plurality of wavy ridges, can be provided, or else rows of protrusions in which each row comprises a plurality of protrusions, in practice cleats, having either wavy or not wavy patterns can be provided.

[0076] According to the disclosure what matters is that also the through-holes 12" of the second plurality of through-holes of the tread 3" face onto the grooves 5", regardless of whether they are provided between rows of protrusions, or between protrusions of the same row or even at protrusions.

[0077] In this regard, in the case of through-holes of the second plurality of through-holes of the tread provided at protrusions, it has to be said that the contact portion with the ground of the tread, next to at least a percentage of protrusions, is equipped with respective round recesses, in practice dome-shaped cavities, the through-holes of the second plurality of through-holes of the tread facing onto the round recesses, the latter embodiment being not shown in the figures.

[0078] Furthermore, it should be said that the side walls 8" of the tread 3" are tilted with respect to the contact portion with the ground 7" of the same tread 3" by an angle between about 110° and about 130°, and according to the example in figure 8, the angle between the side walls 8" and the contact portion with the ground 7" is about 120°.

[0079] This way, the overlapping of the side walls 8" on the midsole 2" can be limited, thus lightening the outsole 1" and limiting the visual impact of the side walls 8" themselves.

[0080] As regards the side walls 8" of the tread 3", it has to be said that they have a concave outer profile at least near the through-holes 9" of the first plurality of through-holes of the tread 3".

[0081] It has to be noted that, according to the example of figure 8, the through-holes 9" are shown with a section substantially equal to the section of the respective end portions of the grooves 5" that are proximal to the side walls 8", but it is also possible to provide through-holes of the first plurality of through-holes of the tread that have a section smaller than the section of respective end portions of the midsole grooves proximal to the side walls of the same tread, analogously to the embodiment described by referring to the example of figures 1-6.

[0082] In this regard, it has to be said that side walls of the tread, having concave outer profile and / or being tilted as described for the outsole 1", can be provided as alternatives to what previously stated for the outsole 1 described with reference to the example of figures 1-6, in which, again as an alternative to what previously stated, "horseback-shaped" channels can be provided similar to the outsole 1" described above.

[0083] However, unless otherwise specified, as regards the other characteristics of the outsole 1", what reported above for the outsole 1 illustrated with reference to the example of the figures 1-6, remains valid and should be considered as reference.

[0084] The advantages of the present invention, already evident in the description above, can be summarized by noting that a breathable outsole for footwear, then also the relative footwear comprising this outsole, is provided and is equipped with better ventilation and greater toughness with respect to the outsoles and footwear provided in known art, the breathable outsole being also particularly comfortable, particularly easy to make and particularly economical.

[0085] In order to meet incidental and specific requirements, several variations and modifications could be made by a field technician to the illustrated and described embodiments of present invention, provided that all are included in the protection scope of the invention as defined by the following claims.

Claims

1. Breathable outsole for footwear, comprising a midsole (2) and a tread (3) constrained to one another, wherein said midsole and said tread comprise respective first pluralities of through-holes, wherein said midsole comprises a lower side (4) facing said tread having a plurality of grooves (5), the through-holes (6) of said first plurality of through-holes of the midsole (2) facing onto the grooves, wherein said tread (3) comprises a contact portion with the ground (7) and side walls (8) extending from said contact portion with the ground (7), the side walls at least partially overlapping said midsole (2) and on which the through-holes (9) of said first plurality of through-holes of the tread (3) being arranged, wherein said through-holes (9) of said first plurality of through-holes of the tread (3) at least partially intercept said grooves (5) of said midsole (2), wherein said grooves (5) of said midsole (2) have a wavy pattern, characterized in that said tread (3) comprises a second plurality of through-holes, wherein the through-holes (12) of said second plurality of through-holes crosses said contact portion with the ground (7) of the tread (3) and wherein said through-holes (12) of said second plurality of through-holes of the tread face onto said grooves (5) of said midsole (2).

2. Outsole according to claim 1, wherein said through-holes (9) of said first plurality of through-holes of the tread (3) have a section smaller than the section of the respective end portions of said grooves (5) proximal to said side walls (8).

3. Outsole according to claim 1 or 2, wherein said side walls (8) are tilted with respect to said contact portion with the ground (7) by an angle between about 90° and about 160°, preferably an angle between about 95° and about 120°.

4. Outsole according to any one of the preceding claims, wherein said side walls (8") have a concave outer profile.

5. Outsole according to any one of the preceding claims, wherein said tread (3) has an upper side (17) and a lower side (11), wherein said upper side (17) has a profile substantially corresponding to the profile of said lower side (11), and wherein preferably said upper side (17) of said tread (3) and said lower side (4) of said midsole (2) are complementary to one another.

6. Outsole according to claim 5, wherein said upper side (17") of said tread (3") has a convex transversal profile next to at least said grooves (5"), and more preferably wherein said lower side (4") of said midsole (2") has a concave transversal profile next to at least said grooves.

7. Outsole according to any one of the preceding claims, wherein said contact portion with the ground (7) of said tread (3) has a length smaller than the length of said midsole (2), said midsole having a first contact portion with the ground (13) and a second contact portion with the ground (14) at the forefoot and, respectively, at the hindfoot of said outsole (1).

8. Outsole according to any one of the preceding claims, wherein said midsole (2) comprises an upper side (15) opposing to said lower side (4), wherein said upper side (15) is provided with a seat (16), the through-holes (6) of said first plurality of through-holes of the midsole (2) facing onto the seat.

9. Outsole according to any one of the preceding claims, wherein said contact portion with the ground (7) of said tread (3) comprises a plurality of protrusions (10), wherein the protrusions of said plurality of protrusions are preferably arranged in rows, wherein said rows preferably have a wavy pattern.

10. Outsole according to any one of the preceding claims , wherein said contact portion with the ground of said tread is provided, next to at least a percentage of said protrusions, with respective dome-shaped recesses, said through-holes of said second plurality of through-holes of the tread facing onto the dome-shaped recesses.

11. Outsole according to any one of claims 8-10, further comprising a layer of waterproof and breathable material sealed, so as to be waterproof, to said midsole (2) inside said seat (16) arranged on said upper side (15) of said midsole.

12. Outsole according to any one of claims 8-11, further comprising at least one protective, preferably breathable, layer consisting of a fabric or a knit made of synthetic material, which is constrained to said midsole inside said seat arranged on said upper side of said midsole.

13. Footwear comprising an outsole according to any one of the preceding claims and an upper constrained to said outsole.