METHOD FOR WATERPROOFING BLANKS OF SHOES, GLOVES, ITEMS OF CLOTHING AND OTHER CLOTHING ACCESSORIES, BLANKS WATERPROOFED WITH THE METHOD, SHOES, GLOVES, ITEMS OF CLOTHING AND OTHER CLOTHING ACCESSORIES PROVIDED WITH THE WATERPROOFED BLANKS

Abstract

A method for waterproofing blanks of shoes, gloves, items of clothing and other clothing accessories, a blank waterproofed by the method and shoes, gloves, items of clothing and other clothing accessories provided by the waterproofed blanks, the method comprising the gluing and pressing on the surface of the blank, on the side intended to remain hidden after its application, of a waterproof and breathable assembly provided by associating a waterproof and breathable functional element in the form of a flexible sheet with at least two meshes that close it in a sandwich-like manner.

Claims

1-16. (canceled)

17. A method for waterproofing blanks of shoes, gloves, items of clothing and other clothing accessories, comprising the gluing and pressing on the surface of said blank, on a side intended to remain hidden after its application, of a waterproof and breathable assembly, wherein said assembly is provided by associating a waterproof and breathable functional element in the form of a flexible sheet with at least two meshes that close it in a sandwich-like manner, at least one of said meshes being interposed between said functional element and said blank.

18. The method according to claim 17, wherein said functional element is made of a polymeric material that is impermeable to water in the liquid state and permeable to water vapor.

19. The method according to claim 17, further comprising providing said functional element by associating a first layer made of expanded polytetrafluoroethylene with a second layer made of hydrophilic polyurethane, the former facing said blank in the coupling of said assembly with said blank, with the interposition of least one of said meshes.

20. The method according to claim 17, wherein said association of said functional element with said at least two meshes is obtained by lamination.

21. The method according to claim 17, wherein said assembly is glued to said blank by application of a matrix of glue.

22. The method according to claim 21, wherein said matrix of glue is produced by the intersection of lines of adhesive.

23. The method according to claim 17, wherein said assembly is glued to said blank by the application of a breathable hydrophilic polyurethane adhesive that is distributed continuously on the entire surface.

24. A blank waterproofed by the method according to claim 17, comprising said blank associated with a said assembly that comprises said waterproof and breathable functional element in the form of a flexible sheet and at least two of said meshes between which said functional element is closed in a sandwich-like manner, at least one of said meshes being interposed between said functional element and said blank.

25. The waterproofed blank according to claim 24, wherein said functional element is made of polyurethane.

26. The waterproofed blank according to claim 24, wherein said functional element is made of expanded polytetrafluoroethylene.

27. The waterproofed blank according to claim 24, wherein said functional element comprises two superimposed layers, said first layer made of expanded polytetrafluoroethylene and said second layer made of hydrophilic polyurethane.

28. The waterproofed blank according to claim 24, wherein it has a water penetration resistance at least equal to 15,000 bending cycles, determined according to the method described in the ASTM D 2099-05 standard.

29. A shoe manufactured with a blank waterproofed by the method according to claim 17.

30. A shoe comprising a waterproofed blank according to claim 24.

31. An item of clothing, manufactured with a blank that is waterproofed by the method according to claim 17.

32. An item of clothing, comprising a waterproofed blank according to claim 24.

Description

[0049] Further characteristics and advantages of the invention will become better apparent from the description of a preferred but not exclusive embodiment of the method and of the waterproofed blank according to the invention, illustrated by way of nonlimiting example in the accompanying drawings, wherein:

[0050] FIG. 1 is an enlarged-scale view of a flap of blank that is waterproofed by means of the method according to the invention, with its superimposed parts shown in cross-section and in view;

[0051] FIG. 2 is a view of the step of the method according to the invention during the coupling of the blank to the assembly.

[0052] With reference to the figures, the method according to the invention allows to obtain a waterproofed blank, generally designated by the reference numeral 10, of shoes, gloves, items of clothing and other clothing accessories. The element to be waterproofed consists of a blank 11 made of leather, fabric but also other similar materials in sheet form, which usually can be used as a replacement of leather and fabric for the above cited applications.

[0053] The method according to the invention is capable of waterproofing the blank 11 with a step of gluing and pressing on its surface, on the side intended to remain hidden after its application, of a waterproof and breathable assembly 12. The assembly 12 is applied to the blank 11 so as to cover its surface completely.

[0054] In particular, coupling occurs by preferably hot pressing the set constituted by the blank 11 and the assembly 12. This operation is performed by means of a flat press or a roller press or a calender.

[0055] The surface of the blank 11, or in an equivalent manner the surface of the assembly 12 that is coupled to the blank 11, is in fact conveniently provided with adhesive, in the manner described hereinafter.

[0056] FIG. 1 is an enlarged-scale view of the waterproofed blank 10 and all its components, including the ones that provide the assembly 12, are indicated.

[0057] FIG. 2 shows a step of the method prior to the coupling of the blank 11 to the assembly 12.

[0058] As clearly visible, the assembly 12 is provided by association of a waterproof and breathable functional element 13 in the form of a flexible sheet with two meshes 14 that close it in a sandwich-like fashion.

[0059] One of the two meshes 14 is therefore interposed between the functional element 13 and the blank 11.

[0060] In particular, the association of the functional element 13 with the two meshes 14 is obtained by lamination.

[0061] More particularly, the meshes 14 are constituted substantially by an open mesh fabric which is very light and made of monofilament nylon, with a thickness comprised approximately in the 0.150.30 mm interval and a weight preferably comprised in the 2040 g/m.sup.2 interval. The monofilament structure and the nylon allow the mesh to not absorb and/or entrain water.

[0062] The functional element 13 is substantially a membrane made of polymeric material that is impermeable to water in the liquid state and permeable to water vapor.

[0063] For example, the functional element 13 can be made of polyurethane, with elasticity characteristics that allow the waterproofed blank 10 to follow the deformations to which the shoe, glove, item of clothing or other clothing accessory for which it is used is subjected, or can be made of expanded polytetrafluoroethylene.

[0064] As an alternative, the functional element 13 is advantageously provided by association of a first layer 15 made of expanded polytetrafluoroethylene (e-PTFE), with a second layer 16 made of hydrophilic polyurethane. In this manner a two-part laminate is obtained which has a monolithic structure.

[0065] The expression monolithic is understood here to reference the typical characteristic of complex structures made of parts that are joined and are not detachable except by breaking one of them.

[0066] In the coupling of the assembly 12 with the blank 11, the first layer 15 is the one of the two that faces the blank 11.

[0067] The two-part functional element 13 is therefore constituted by the two superimposed layers, the first layer 15 and the second layer 16, which correspond respectively to the layer made of e-PTFE and to the layer made of hydrophilic polyurethane, and is coupled at the first layer 15 with a mesh 14 that is interposed between it and the blank 11.

[0068] This assembly order is due to the characteristics of the two components.

[0069] Expanded PTFE is by definition a porous, highly hydrophobic and water-repellent material, which has an extremely low angle of contact with the water droplet. Passage of water vapor occurs by means of a convective and partial pressure differential model through the microporosity of the structure of the expanded PTFE.

[0070] This structure is constituted by a set of nodes and fibrils, generated by the stretching action that follows the extrusion of the PTFE.

[0071] The first layer 15 of the functional element 13 therefore advantageously constitutes a water-repellent barrier against the water that arrives from the side of the blank 11.

[0072] Vice versa, the hydrophilic polyurethane is a highly hygroscopic material that has a greater angle of contact and affinity with the water droplet.

[0073] The passage of water vapor occurs according to a diffusion model through the extremely low thickness of the polyurethane layer. The water molecules are adsorbed by the hygroscopic material, conveyed along the structure of the material and de-adsorbed on the opposite side due to the partial vapor pressure differential.

[0074] The second layer 16 of the functional element 13, which is directed opposite with respect to the blank 11, therefore facilitates advantageously the evaporation of sweat or moisture that arrives from the side that is opposite to the side of the blank 11.

[0075] The first layer 15 made of expanded PTFE gives a high level of water repellency and breathability to the functional element 13, the second layer 16 of hydrophilic polyurethane gives strength and elasticity.

[0076] These characteristics of the hydrophilic polyurethane layer are advantageous, since expanded PTFE membranes can be elongated but are substantially non-elastic.

[0077] The provision of the functional element 13 in the version as a two-part laminate can occur by spreading a hydrophilic polyurethane in the fluid state, directly and continuously, on a film of hydrophobic e-PTFE. Then the hydrophilic polyurethane solidifies on the porous structure of the e-PTFE film.

[0078] As an alternative, the functional element 13 can be constituted equally advantageously by a lamination that has a sheet-like, monolithic, stratified and cohesive structure comprising a plurality of functional layers made of polymeric material, preferably e-PTFE, which is impermeable to water in the liquid state and permeable to water vapor.

[0079] The expression sheet-like is understood to reference the shape characteristic of a structure that has one dimension that is reduced considerably with respect to the other two, said dimension being its thickness, which in any case, according to what is commonly understood to differentiate a plate from a lamina or a membrane, remains significant.

[0080] However, it should not be understood that this shape characteristic in itself compromises the bendability or flexibility of the lamination.

[0081] The second figure shows the method in an instant that precedes the adhesive bonding of the assembly 12 to the blank 11. The figure shows that the assembly 12 is glued to the blank 11 by applying a matrix of glue 17 produced by the intersection of lines of adhesive, preferably a polyurethane adhesive.

[0082] In the example given, the glue matrix 17 is spread on the surface of the mesh 14 that faces the blank 11, but it can be applied in an equivalent manner to the surface of the blank 11, the one at the face that is intended to remain hidden during its use.

[0083] As an alternative it is possible to apply breathable hydrophilic polyurethane adhesive that is distributed continuously on the entire surface of the blank 11 or on the mesh 14.

[0084] The blank 10 waterproofed by means of the method according to the invention therefore comprises a blank 11 with which an assembly 12 is coupled which comprises a waterproof and breathable functional element 13, such as a membrane with these characteristics, and two meshes 14 between which the functional element 13 is closed in a sandwich-like fashion.

[0085] The waterproofed blank 10 according to the invention thus provided and structured has a water penetration resistance at least equal to 15,000 bending cycles, determined according to the method presented in the ASTM D 2009-05 standard.

[0086] Said ASTM D 2009-05 standard describes a testing method that simulates the flexing of the upper of a shoe during real use.

[0087] A specimen of the waterproofed blank 10 measuring 101.63.2101.63.2 mm is fastened between two V-shaped clamps which are parallel and spaced by 6352.5 mm, with the blank 11 downward and the assembly 12 upward. Approximately 400 clean and degreased steel balls which have an intrinsic maximum electrical resistance of 7500 are inserted in the pocket created by the specimen thus assembled, on the side of the assembly 12. One clamp is fixed while the other one performs an eccentric motion at the rate of 905 RPM. In one rotation, the tip of the movable clamp moves by 25.41.3 mm below the horizontal. The specimen moves within a solution of NaCl at a concentration of 1 g/L, so that the level of the liquid is 19.11.3 mm above the lowest point of the specimen that is adjacent to the fixed clamp, in contact with the solution on the side of the blank 11.

[0088] In order to determine the number of bending cycles linked to resistance to water penetration, the electrical resistance between the tank that contains the saline solution in continuous contact with the specimen and the steel balls is recorded.

[0089] After 15,000 bending cycles, the waterproofed blank 10 according to invention is found to be still waterproof.

[0090] By means of the described method it is possible to waterproof blanks to be used in the provision of shoes, where the blank 11 constitutes their upper, and of items of clothing, for example jackets.

[0091] The blank 10 waterproofed by means of the described method can be used advantageously also in the production of gloves and other clothing accessories, for example bags and wallets.

[0092] It should be noted that the mesh 14, by being interposed between the functional element 13 and the blank 11, improves the grip of the adhesive to the assembly 12 and to the blank 11.

[0093] Furthermore, advantageously the mesh 14 constitutes a reinforcement structure for the functional element 13. The tension produced by the flexing of the blank 11 is discharged on the mesh 14, which constitutes a sort of frame for the functional element 13.

[0094] In a similar manner, the matrix of glue 17, produced by the intersection of lines of glue, constitutes a reinforcement structure for the assembly 12. The tension produced by the flexing of the blank 11 is discharged uniformly along the lines of the matrix of glue 17, which constitutes a sort of frame for the assembly 12, avoiding the isolated tension peaks that are characteristic of gluing performed by isolated spots.

[0095] The functional element 13 is capable of returning rapidly and perfectly to its original dimensions as a consequence of flexural deformation such as that produced by walking for the case of a shoe.

[0096] Therefore, the waterproofed blank 10 according to the invention is not only waterproof and breathable but also has wear resistance characteristics thanks to the matrix of glue 17 and to the presence of the second layer 16 made of hydrophilic polyurethane.

[0097] Furthermore, the excellent coupling of the assembly 12 to the blank 11, which is due not only to pressing but also to the presence of the mesh 14 and to the use of a matrix of glue 17, prevents the formation of water pockets between the blank 11 and the assembly 12, while not preventing the vapor permeation of the waterproofed blank 10, without the choice of the functional element 13, i.e., the membrane indicated in the background art, having to be limited by its inherent elasticity characteristic.

[0098] In practice it has been found that the invention achieves the intended aim and objects, by providing a method for waterproofing blanks, particularly of shoes, gloves, items of clothing and other clothing accessories, ensuring the breathability of the product and at the same time preventing the formation of water pockets by way of the presence of the two meshes that close the functional element in a sandwich-like manner and by way of the optimum grip of the assembly to the blank.

[0099] Furthermore, it has been found that wear resistance is such as to ensure the waterproofness of the blank after a large number of bending cycles without imposing restrictive constraints in the choice of the functional element.

[0100] The invention thus conceived is susceptible of numerous modifications and variations, all of which are within the scope of the appended claims; all the details may further be replaced with other technically equivalent elements.

[0101] In practice, the materials used, so long as they are compatible with the specific use, as well as the contingent shapes and dimensions, may be any according to requirements and to the state of the art.

[0102] The disclosures in Italian Patent Application No. PD2014A000185 from which this application claims priority are incorporated herein by reference.

[0103] Where technical features mentioned in any claim are followed by reference signs, those reference signs have been included for the sole purpose of increasing the intelligibility of the claims and accordingly such reference signs do not have any limiting effect on the interpretation of each element identified by way of example by such reference signs.