Waterproof and water vapour-permeable footwear articles

Abstract

The present invention relates to a waterproof and water vapor permeable footwear article, comprising an upper, an insole and a sole, wherein the upper comprises an outer material on the outside of the upper, a waterproof and water vapor permeable membrane facing the inside of the footwear article and a meltblown layer located between the outer material and the waterproof and water vapor permeable membrane; and the use of a laminate comprising a waterproof and water vapour permeable membrane and a meltblown layer for preventing or reducing wicking.

Description

[0001] TITLE OF THE INVENTION WATERPROOF AND WATER VAPOUR-PERMEABLE FOOTWEAR ARTICLES

[0002] FIELD OF THE INVENTION

[0003] The present invention relates to waterproof and water vapour permeable footwear articles and more particularly to waterproof and water vapour permeable footwear articles comprising a waterproof and water vapor permeable membrane and a meltblown layer to prevent or reduce wicking of moisture. The present invention further relates to the use of a water vapor permeable membrane and a meltblown layer for preventing or reducing wicking of moisture.

[0004] BACKGROUND OF THE INVENTION

[0005] Waterproof and water vapour permeable footwear articles are used for a variety of purposes, such as every day footwear, outdoor sports, for example hiking, and heavy duty work such as in the field of fire safety, health work, police, machinery and defence. All these footwear articles have in common that the foot of the wearer needs to be protected from moisture from both the inside (sweat) and the outside (rain, puddles, etc.) to provide maximum comfort. Often a waterproof and water vapour permeable membrane is therefore placed on the inside of the outer material of the upper and is either attached at the top of the upper and / or some other points; or adhered (laminated) to the outer material of the upper.

[0006] It is particularly important to keep moisture out of all parts of the footwear article as it is possible for moisture to enter between layers and to wick into the footwear article. Very often water on the outside can enter the footwear article through the outer layer of the upper and then remain between the outer layer and the waterproof and water vapor permeable membrane or even wick up along the membrane or other layers that may be present on the inside of the outer material to enter the inside of the footwear via the foot entry opening. This can lead to deterioration of the footwear article, increases the weight of the footwear and reduces the comfort for the wearer of the footwear, as the footwear either feels cool or the foot becomes wet. A waterproof and water vapour permeable membrane generally does not possess sufficient abrasion resistance to constitute the outer layer of a footwear article. In addition, a lot of the appeal of a footwear article for the consumer is the look and the comfort of the footwear articles.

[0007] This is why a lot of different materials are available as outside layers of footwear articles. Some materials, particularly hydrophilic materials or materials with hydrophilic components, forming part of the outer material or the waterproof and water vapour permeable membrane of the upper of a footwear article, and / or lamination adhesives are particularly prone to wick moisture to the inside of the footwear article and thus the use of these materials is restricted. This is why outer materials often are treated to prevent wicking.

[0008] It has therefore been an object of the present invention to provide footwear articles which prevent or reduce wicking of moisture from the outside into the footwear articles. It is a further object of the present invention not to restrict the materials used in the upper, in particular the waterproof and water vapor permeable membrane, adhesives and outer materials of the upper of a footwear article, in particular when the upper comprises hydrophilic materials as discussed above.

[0009] SUMMARY OF THE INVENTION

[0010] A first aspect of the present application refers to a waterproof and water vapor permeable footwear article, comprising an upper, an insole and a sole, wherein the upper comprises an outer material on the outside of the upper, a waterproof and water vapor permeable membrane facing the inside of the waterproof and water vapor permeable footwear article and a meltblown layer located between the outer material and the waterproof and water vapor permeable membrane.

[0011] The upper may further comprise an inner layer facing the inside of the footwear article. The meltblown layer may be laminated to the waterproof and water vapor permeable membrane and optionally to the outer material.

[0012] The waterproof and water vapor permeable membrane may be hydrophilic, comprise a hydrophilic coating on the surface that is facing the meltblown layer or be hydrophilically imbibed. The term “hydrophilically imbibed” means that a hydrophilic agent is present in the pores and on the surface of the waterproof and water vapor permeable membrane. A hydrophilic layer may be located between the waterproof and water vapor permeable membrane and the meltblown layer. The hydrophilic layer may comprise an adhesive layer and / or a textile layer.

[0013] The meltblown layer may comprise hydrophobic filaments, optionally elastic hydrophobic filaments. The meltblown layer may consist of hydrophobic filaments, optionally elastic hydrophobic filaments. The meltblown layer may comprise or consist of polyurethane filaments. The meltblown layer may comprise or consist of thermoplastic polyurethane (TPU). The meltblown layer may comprise thermoplastic polyurethane filaments or polyamide filaments.

[0014] The meltblown layer may comprise filaments with a medium diameter of from 0.5 to 30 pm. The filaments may have a medium diameter of from 4 to 20 pm. The filaments may have a medium diameter of from 5 to 15 pm. The filaments may have a medium diameter from 6 to 10 pm. The meltblown layer may have an areal weight of 10 to 70 gsm. The meltblown layer may have an areal weight of 10 to 50 gsm. The meltblown layer may have an areal weight of 10 to 40 gsm. The meltblown layer may have an areal weight of 10 to 30 gsm.

[0015] The inner layer and / or the meltblown layer may be attached to the waterproof and water vapour permeable membrane with an adhesive. The adhesive may be applied continuously between the layers. The adhesive may be applied discontinuously, optionally in a pattern that comprises dots, shapes and / or lines of adhesive. The adhesive may be hydrophilic. The adhesive may be hydrophobic. The adhesive may be water vapour permeable. The adhesive may not be water vapour permeable.

[0016] A second aspect of the present application refers to the use of a laminate comprising a waterproof and water vapour permeable membrane and a meltblown layer for preventing or reducing wicking. The laminate may be used in the upper of a waterproof and water vapor permeable footwear article.

[0017] The meltblown layer may be facing towards the outside of the footwear article.

[0018] The laminate may further comprise an inner layer that is laminated to the surface of the waterproof and water vapour permeable membrane that is opposite of the meltblown layer. A hydrophilic layer may be located between the waterproof and water vapor permeable membrane and the meltblown layer. The waterproof and water vapor permeable membrane may be hydrophilic, comprise a hydrophilic coating on the surface that is facing the meltblown layer or be hydrophi lical ly imbibed.

[0019] BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 General representation of a laminate in a footwear article of the present invention;

[0021] Figure 2 a laminate in a footwear article of the present invention;

[0022] Figure 3 a laminate in a footwear article of the present invention;

[0023] Figure 4 a laminate in a footwear article of the present invention;

[0024] Figure 5 a laminate in a footwear article of the present invention;

[0025] Figure 6 a laminate in a footwear article of the present invention;

[0026] Figure 7 a laminate in a footwear article of the present invention.

[0027] DETAILED DESCRIPTION

[0028] While the making and using of various embodiments of the present invention are discussed in detail below, it should be appreciated that the present invention provides many applicable inventive concepts that can be embodied in a wide variety of specific contexts. The specific embodiments discussed herein are merely illustrative of specific ways to make and use the invention and do not delimit the scope of the invention.

[0029] To facilitate the understanding of this invention, a number of terms are defined below. Terms defined herein have meanings as commonly understood by a person of ordinary skill in the areas relevant to the present invention. Terms such as "a", "an" and "the" are not intended to refer to only a singular entity, but include the general class of which a specific example may be used for illustration. The terminology herein is used to describe specific embodiments of the invention, but their usage does not delimit the invention, except as outlined in the claims.

[0030] The term waterproof and water vapour permeable footwear article refers to outer coverings for feet such as shoes, boots, trainers, sneakers and the like. The present invention relates to a footwear article comprising an upper, an insole and a sole. The footwear article is waterproof and water vapour permeable. The upper comprises an outer material. The outer material provides the outer surface of the upper facing the exterior of the footwear article.

[0031] The outer material can be made from any material that is typically used for this purpose Examples include leather, synthetic leather (faux leather) and textile fabrics. Typically, textile fabrics comprise polyester, polypropylene, polyamide (e.g. nylon) or cotton. The outer material may be a laminate comprising two or more layers of the above materials.

[0032] Textile fabrics may comprise filaments, such a monofilaments or multifilaments, or fibres, or any mixtures thereof. Fibres include natural and synthetic fibres and any mixtures thereof. Natural fibres include cellulosic types such as cotton, hemp or linen; animal fibres such as silk, angora, sheep’s wool, alpaca, cashmere, mohair and any combination thereof.

[0033] Synthetic fibres include fibres based on acrylic polymers, polyesters, polyolefins, polyurethanes, polyamides and any combination thereof. Polyurethanes may be elastic fibers such as spandex or elastane. The textile fabrics may be knit fabrics, woven fabrics, or nonwoven fabrics. The fabrics may stretch. The stretchiness may be due to the use of stretchable yams or fibres, made for example from elastomers. The stretchiness may be due to the way the yams or fibres are knitted or woven.

[0034] The upper further comprises a meltblown layer. The meltblown layer may be attached to the outer layer with adhesive. The adhesive may be applied continuously in one continuous layer or discontinuously, for example with dots, lines and / or shapes. Alternatively, the meltblown layer and the outer layer may be attached to each other only at or additionally along their perimeters. The meltblown layer may be directly attached to the outer layer with or without an adhesive layer and / or with no further textile layer being present.

[0035] The meltblown layer may be a nonwoven sheet that has been prepared by a meltblown process. In the meltblown process a polymer resin is melted and extruded through a spinneret or nozzle. High-speed hot air or gas is blown onto the extruded polymer streams which leads to stretching and elongation of the molten polymer into filaments that are collected on a moving conveyor belt or drum. The resulting nonwovens are porous.

[0036] The meltblown layer may comprise hydrophobic filaments. The hydrophobic filaments may be elastic. The meltblown layer may comprise a thermoplastic polymer. The thermoplastic polymer may be an elastic thermoplastic polymer. The meltblown layer may comprise or consist of polyurethane (Pll). The polyurethane may be thermoplastic polyurethane (TPU). The meltblown layer may consist of polyurethane (Pll). The meltblown layer may consist of thermoplastic polyurethane (TPU).

[0037] The meltblown layer may comprise filaments with a medium diameter of 0.5 to 30 pm. The meltblown layer may comprise filaments with a medium diameter of 4 to 20 pm. The meltblown layer may comprise filaments with a medium diameter of 5 to 15 pm. The meltblown layer may comprise filaments with a medium diameter of 6 to 10 pm.

[0038] The meltblown layer may have an areal weight of 10 to 70 gsm. The meltblown layer may have an areal weight of 10 to 40 gsm. The meltblown layer may comprise filaments with a medium diameter of 4 to 20 pm and an areal weight of 10 to 40 gsm.

[0039] The meltblown layer may be attached with the surface that is facing the inside of the footwear article to the waterproof and water vapor permeable membrane with an adhesive or with a seam. The adhesive may be applied continuously over the whole area or discontinuously, for example in lines, dots, patterns or combinations thereof. The adhesive may be a hydrophilic adhesive or a hydrophobic adhesive. The hydrophobic adhesive may be applied in a discontinuous pattern. The hydrophilic adhesive may be applied in a continuous or discontinuous pattern. The adhesive may be water vapor permeable or not water vapor permeable. When the adhesive is not water vapor permeable it should be used in a discontinuous pattern to allow water vapor permeability.

[0040] The meltblown layer is abrasion resistant, stain-resistant. The meltblown layer may be the outer layer of the upper. The meltblown layer or the upper comprising the meltblown layer may be assembled from more than on material pieces which are attached to each other with a waterproof seam tape. The seam tape may have more than one layer and may comprise an adhesive layer.

[0041] The surface of the waterproof and water vapor permeable membrane that is facing the inside of the footwear article may be attached to an inner layer. The inner layer may be attached to the waterproof and water vapor permeable membrane with an adhesive. The same adhesives discussed above with regard to the attachment of the meltblown layer to the waterproof and water vapor permeable membrane are suitable for the attachment of the inner layer to the waterproof and water vapor permeable membrane.

[0042] The inner layer may provide mechanical protection of the waterproof and water vapor permeable membrane and also padding for the foot of the wearer. In addition, the inner layer may help to transport any moisture from the inside of the footwear article to the outside thereof.

[0043] Suitable inner layers may comprise leather, faux-leather and / or nonwovens or knit fabrics. The nonwovens may be spun-bonded, spunlace, heat bonded, hydroentangled or needle punched. Knit fabrics may comprise weft-knit or warp-knit fabrics. Thicker materials may provide warmth and comfort and are ideal for transport of moisture towards the waterproof and water vapor permeable membrane. The inner layer may be a meltblown inner layer. The inner layer may comprise more than one layer. For example, the inner layer may be a laminate of a layer that is directly attached to the waterproof and water vapour permeable membrane and a layer facing the inside of the footwear article that provides padding, warmth or moisture transport from the inside of the footwear article towards the membrane. This inner layer may be a laminate of a nonwoven and a knit.

[0044] The inner layer may comprise synthetic polymers such as polyamides, polyurethanes, polyesters and / or copolymers thereof. Alternatively the inner layer may comprise natural fibers, such as fibers originating from animals, for example sheep wool, mohair or silk, or plant fibers, for example cotton.

[0045] The meltblown layer, waterproof and water vapor permeable membrane and the inner layer may be provided as a laminate. The laminate may consist of the meltblown layer, the waterproof and water vapor permeable membrane, the inner layer and adhesive between the layers.

[0046] The waterproofness of footwear may be determined by use of the Centrifuge test described in U.S. Pat. No. 5,329,807, and incorporated by reference herein in its entirety. The centrifuge tests may be carried out for 30 minutes. The footwear article is considered to be waterproof if no leakage is seen after 30 minutes.

[0047] The water vapour permeability of footwear may be assessed in accordance with the determination of the Whole Boot Moisture Vapor Transmission Rate Test in accordance with the Department of Defense Army Combat Boot Temperate Weather Specifications. The specifications are as follows:

[0048] Whole boot water vapour permeability

[0049] The boot vapour permeability test shall be designed to indicate the Moisture Vapor Transmission Rate (MVTR) through the test sample by means of a difference in concentration of moisture vapor between the interior and the exterior environment.

[0050] Apparatus a) The external test environment control system shall be capable of maintaining 23 (± 1 ) °C and 50% ± 2% relative humidity throughout the test duration. b) The weight scale shall be capable of determining the weight of test samples filled with water to an accuracy of (± 0.01 ) gram. c) The water holding bag shall be flexible so that it can be inserted into the test sample and conform to the interior contours; it must be thin enough so that folds do not create air gaps; it must have much higher MVTR than the footwear product to be tested; and it must be waterproof so that only moisture vapor contacts the interior of the footwear product rather than liquid water. d) The internal heater for the test sample shall be capable of controlling the temperature of the liquid water uniformly in the test sample to 35 (± 1 ) °C. e) The sealing method around the collar of the test sample shall be impervious to both liquid water and water vapour. Procedure a) Place sample in test environment and condition for at least 12 hours. b) The heating device is inserted into the water holding bag and the complete assembly is then placed into the test sample opening and filled with water to a height of 5 cm measured from inside sole. c) Seal opening around the collar with plastic wrap around the top of the footwear and tape over using packaging tape. d) Heat water in test sample to 35 °C. e) Weigh test sample and record as Wi. f) Hold temperature in test sample after weighing for a minimum of 4 hours. g) After a minimum of 4 hours, reweigh test sample. Record weight as Wf and test duration as Td. h) Calculate MVTR of the test sample in grams / hour from the equation below: i) MVTR = (Wi - Wf) / Td.

[0051] This test is in accordance with ASTM D8041 (2016). For example, for a low ankle shoe of European shoe size 42, the footwear may be considered breathable if above calculated value is above 1.5 grams / hour. For larger or smaller shoe sizes, said limit value may be extrapolated in accordance with the increased or decreased surface area of the shoe.

[0052] The waterproof and water vapour permeable membrane is considered to have waterproof characteristics when the requirements specified in DIN EN 343 (2010) are met, i.e. a test of the liquid water resistance with respect to hydrostatic water pressure according to EN 20811 (1992) yields a liquid water resistance Wp of 8000 Pa, or more. Water vapor permeability of the waterproof and water vapour permeable membrane is tested and defined in EN ISO 15496, also known as the "Cup Test". A 20 cm x 20 cm or a circular 0 100mm sample of the waterproof and water vapour permeable membrane is placed onto a container containing water and covered with a water vapor permeable and waterproof membrane. Then a cup containing potassium acetate and being covered by the same membrane is placed on the sample. Water vapor passes through the waterproof and water vapour permeable membrane into the cup, whose weight increase is then determined. The waterproof and water vapor permeable membrane is considered water vapor permeable or breathable if the water vapor permeability is greater than or equal to 0.01 g / (Pa m2h). If the required size of the sample cannot be obtained, a smaller sample may be used for the measurement using a smaller cup containing half the amount of potassium acetate specified in the Norm, i.e. 50g instead of 100g and mixed with 15.6g of water. The terms water vapor permeability and breathability are used interchangeably herein.

[0053] Non-limiting examples of suitable membranes which are waterproof and water vapour permeable include polyurethanes, polytetrafluoroethylene (PTFE), expanded polytetrafluoroethylene (ePTFE), polyvinylidene fluoride (PVDF), fluorinated ethylene propylene (FEP), perfluoroalkoxy alkane (PFA), modified polytetrafluoroethylene polymers, tetrafluoroethylene (TFE) copolymers, polyalkylenes such as polypropylene and polyethylene, polyether sulfone (PES), polyesters, poly (p-xylylene) (ePPX) as taught in U.S. Patent Publication No. 2016 / 0032069, porous ultra-high molecular weight polyethylene (eUHMWPE) as taught in U.S. Patent No. 9,926,416 to Sbriglia, U.S. Patent Application No. 2021 / 0317276 to Bell, PCT Patent Application No. 2020 / 282328 to Bell, PCT Patent Application No. 2020 / 28331 to Bell, porous ethylene tetrafluoroethylene (eETFE) as taught in U.S. Patent No. 9,932,429 to Sbriglia, porous polylactic acid (ePLLA) as taught in U.S. Patent No. 7,932,184 to Sbriglia, et al., porous vinylidene fluoride-co-tetrafluoroethylene or trifluoroethylene [VDF-co-(TFE or TrFE)] polymers as taught in U.S. Patent No. 9,441 ,088 to Sbriglia and copolymers and combinations thereof.

[0054] The waterproof and water vapor permeable membrane may comprise at least one of expanded polytetrafluorethylene (ePTFE), expanded polyethylene, expanded polypropylene, expanded polyolefins, polyurethane, polyester and copolyether ester, polyether, expanded polyether, polyamide, copolyether amides and polyacrylate, and composites or multilayer laminates thereof. The waterproof and water vapor permeable membrane may be made of a fluoropolymer, particularly made of microporous expanded polytetrafluorethylene (ePTFE). In embodiments, the waterproof and water vapor permeable membrane may be made of porous (i.e., expanded) ultrahigh molecular weight polyolefin, particularly made of microporous expanded ultrahigh molecular weight polyethylene. The water vapor permeable and waterproof membrane may be composed of a polyurethane coated microporous expanded ultrahigh molecular weight polyethylene membrane made for example io substantially according to the teachings of PCT Patent Application No. 2020 / 282328 to Bell.

[0055] The microporous polytetrafluoroethylene waterproof and water vapour permeable membrane may be a membrane of expanded polytetrafluoroethylene as taught in US 3,953,566 and US 4,187,390. Such membranes of expanded polytetrafluoroethylene are present in commercially available fabrics from W. L. Gore and Associates, under the tradename GORE-TEX® fabric. The water vapor permeable and waterproof membrane may be composed of a polyurethane coated microporous expanded polytetrafluoroethylene membrane made substantially according to the teachings of US 4,194,041 and US 4,942,214 assigned to W. L. Gore and Associates, Inc, in Elkton, Md. At least one further support material such as a knitted textile on one or both sides of the membrane may be present.

[0056] The waterproof and water vapor permeable membrane may have at least one hydrophilic surface. The at least one hydrophilic surface may be facing the outside of the footwear article. There may be at least one hydrophilic layer between the waterproof and water vapor permeable membrane and the meltblown layer. The hydrophilic layer may comprise an adhesive layer and / or a textile layer.

[0057] The term "hydrophilic" as used herein refers to a material or surface of a material that has a contact angle of equal to or less than 105 degrees. The "contact angle" is defined as the angle between the substrate and a line tangent to the liquid droplet at the point at which the liquid contacts the substrate. The subjects of wettability and contact angles are discussed in detail by Milton J. Rosen in Surfactants and Interfacial Phenomena, 2ndEdition, John Wiley & Sons, Inc., 1989. The term “hydrophilic” as used herein may refer to a material or surface of a material that has a contact angle of equal to or less than 100 degrees, optionally equal to or less than 95 degrees.

[0058] The footwear article may further comprise an insole. The insole may be made of any suitable material such as for example bonded leather, synthetic fabrics, laminates of a waterproof and water vapor permeable membrane and a textile, thermoplastic polymers, fibreboard or rubber. The insole may be a lasting board, a strobel board, a net board or a toe lasting board. A lasting board may have a higher stiffness and hardness than a strobel board. A strobel board is typically a textile material to enable stitching of the spacer and / or the liner to the strobel board. A toe lasting board is a lasting board with smaller dimensions to allow for sealing of the bootie between the toe lasting board and the seam sewing of the strobel board to the bootie.

[0059] Typical lasting adhesives such as hotmelt or pressure sensitive adhesives can be used, for example co-polyester or polyamide hotmelt adhesives or polyurethane.

[0060] The sole may be made from a polymeric material such as polyurethane, thermoplastic polyurethane (TPU) or ethylene vinyl acetate (EVA) and injected over the bottom of the footwear construction that is assembled on a last. Alternatively the sole can be cemented onto the upper.

[0061] At the end of the manufacturing process a footbed may be placed into the waterproof and water vapor permeable footwear article. The footbed may be made from material that cushions the foot of the wearer and provides a better fit and further thermal insulation.

[0062] The footbed may comprise two layers of material. The bottom layer facing the sole may be made from for example polyurethane (Pll) foam, ethylene-vinyl acetate (EVA), ad / or polyethylene (PE) foams. The upper layer facing the foot of the wearer may be made from any of the materials disclosed for the liner. The footbed may be removable and not be attached to the insole and / or liner.

[0063] As shown in Figure 1 , a laminate (100) in an upper of a footwear article is provided, comprising on the surface facing the outer layer of the footwear article a meltblown layer (110). The meltblown layer (110) is attached to a waterproof and water vapour permeable membrane (120) by a continuous layer of adhesive (140a). On the opposite surface of the waterproof and water vapor permeable membrane (120) an inner layer (130) is attached with a discontinuous layer of adhesive (140).

[0064] Figures 2 to 7 show several embodiments of the present invention. In Figure 2, the meltblown layer (110) is attached to a hydrophilically imbibed waterproof and water vapor permeable membrane (120) with a continuous layer of a hydrophilic adhesive (140a). The hydrophilicity of the adhesive (140a) ensures the breathability of the laminate, i.e. allows for water vapor to move from the inside to the outside of the footwear article.

[0065] The opposite surface of the waterproof and water vapor permeable membrane (120) is attached to the inner layer (130). In this embodiment shown in Figure 2, this inner layer (130) is knit textile layer which may comprise polyamide (PA) or polyamide (PA) monofilaments. A discontinuous adhesive layer (140b) of a hydrophobic adhesive adheres the waterproof and water vapor permeable membrane (120) to the inner layer (130).

[0066] Figure 3 shows an embodiment which in contrast to the embodiment of Figure 2 comprises a hydrophilic waterproof and water vapor permeable membrane. This shows the versatility of the laminate of the present application to work with a variety of different membranes.

[0067] Figures 4 and 5 have a spunbond nonwoven textile layer as the inner layer (130). Whilst the embodiment of Figure 4 comprises a hydrophi lical ly imbibed waterproof and water vapor permeable membrane (120), the waterproof and water vapor permeable membrane (120) of Figure 5 is a hydrophilic membrane.

[0068] Figures 6 and 7 show embodiments with laminates (100) where both adhesive layers (140a) and (140b) are discontinuous hydrophobic adhesives. As hydrophobic adhesives tend not to allow transport of water vapor there through, it is important to use discontinuous patterns of adhesive such as dots or lines to allow for areas where the water vapor can move through the adhesive layer. However, these patterns should at the same time allow for a secure attachment between the waterproof and water vapor permeable membrane (120) and the inner layer (130) or the meltblown layer (110).

[0069] The laminates in the upper of the footwear articles of the present invention avoid wicking of moisture from the outside of the footwear article into the area between the outer layer and the waterproof and water vapor permeable membrane. Any fluid accumulating in this area will lead to discomfort for the wearer, for example because of the additional weight and insufficient thermal insulation from the outside, and in the long run also lead to deterioration of the outer layer.

[0070] The laminates of the footwear articles of the present invention have been tested with regard to their wicking properties and the contact angles of their hydrophilic components.

[0071] Examples

[0072] Vertical Wicking Test Method

[0073] The amount of liquid water which is able to wick in the laminates was investigated by a test method based on DIN 54924:2020-09, with deviations from that test norm described below. The goal is to detect the wicking height of the liquid.

[0074] As test liquid, distilled water including a concentration of 0.15% colorant (Solophenyl Turquoise BRL 400%) at a temperature of 23°C was used. The water bath needed to have a minimum depth of 13 mm. Laminate specimens had a size of 25 mm in width, and 75 mm in length. A marking was added across the width of the samples at a distance of 10 mm from the end of the specimen to be tested. The specimens were attached to a holder at the top of the samples (e.g. by clips).

[0075] The specimens were then conditioned at 20°C and a humidity of 50 to 65%. After conditioning and preparation of the specimens, the end of the specimens were placed into the test solution so that the 10 mm marking was at water level. The laminate specimens were left immersed for 120 minutes. The bath and samples were not covered during that time. After the test time of 120 minutes, the laminate specimens were removed from the test solution and analysed immediately.

[0076] Analysis included visual inspection and measurement of the maximum height per sample above the 10 mm mark on the surface of the laminate that would face the outside of the footwear article, i.e. the outer layer shown below in the table.

[0077] The following laminates were measured as described above.

[0078] Table 1 : Wicking of the outer layer of different laminates

[0079] The examples 1 and 2 comprise a meltblown layer as the outer layer laminated to a waterproof and water vapour permeable membrane. Both of these examples don’t show any wicking through the meltblown layer and / or along the membrane despite the presence of a hydrophilic adhesive or hydrophilic / hydrophilically imbibed membrane. When the meltblown layer is substituted with a knit or a spunbond layer, wicking occurs. If the materials of examples 3 to 5 were used in footwear articles water would wick up the outer side of the laminate and the membrane and enter the footwear article at the opening for the foot of the wearer.

[0080] Contact Angle Measurement

[0081] Samples were cut in 5 cm x 1 cm pieces and placed flat onto a sample holder. The sample on the sample holder was then placed into a Drop Shape Analyser DSA 100 (Kruss GmbH) which uses Advance software. Measurements were made at a humidity of 65 % and at a temperature of 20 °C.

[0082] A syringe with DI water (<20 psiemens) was positioned at a speed of 300 mm / min at 2mm above the sample, position 1 . The syringe was then lowered down at a speed of 100 mm / min such that the tip of the syringe was touching the top of the droplet, after the droplet had been positioned on the surface. The droplet had a volume of 40pL and was placed onto the sample at a dosing speed of 30pL / s. The syringe was then lifted away from the sample back to position 1 at a speed of 100 mm / min and then further up at a speed of 300 mm / min. The static contact angle was then measured on both the left and the right side of the droplet with a horizontal microscope wherein the baseline was adjusted manually, if required. The contact angle was measured after 2 mins.

[0083] This measurement was repeated 4 times on the sample with the following table providing the average of these 10 values (contact angle on both left and right side of droplet visible through the microscope measured 5 times).

[0084] Table 2: Contact Angles

[0085] Table 2 shows the hydrophilicity of the membrane and the adhesives used in the Examples of Table 1 .

[0086] Materials used in examples 1 to 9:

[0087] Knit = polyamide 6, monofil warp knit Charmeuse, filament 22f1 , 30 g / m2

[0088] Spunbond = N03020 provided by Asahi Kasei, Japan.

[0089] Meltblown = MB-D-30-B, polyurethane, Neenah-Gessner, Mativ-Brand, Feldkirchen Westerham, Germany.

[0090] Hydrophobic adhesive = Jowatherm-Reaktant® PUR-Hotmelt.

[0091] Hydrophilic adhesive = in accordance with US Pat. No. 4925732.

[0092] Hydrophilic membrane = WPC-T4Wfrom Foshan Kingwonder Easytex.

[0093] Hydrophilically imbibed membrane = expanded polyethylene according to International Patent Application No. W02020028328 and W02020028331 .

Claims

CLAIMS1 . Waterproof and water vapor permeable footwear article, comprising an upper, an insole and a sole, wherein the upper comprises an outer material on the outside of the upper, a waterproof and water vapor permeable membrane facing the inside of the footwear article and a meltblown layer located between the outer material and the waterproof and water vapor permeable membrane.

2. The waterproof and water vapor permeable footwear article according to claim 1 , wherein the upper further comprises an inner layer facing the inside of the footwear article.

3. The waterproof and water vapor permeable footwear article according to any one of claims 1 or 2, wherein the meltblown layer is laminated to the waterproof and water vapor permeable membrane and optionally the outer material.

4. The waterproof and water vapor permeable footwear article according to any one of claims 1 to 3, wherein the waterproof and vapor permeable membrane is hydrophilic, comprises a hydrophilic coating on the surface that is facing the meltblown layer or is hydrophi lical ly imbibed.

5. The waterproof and water vapor permeable footwear article according to any one of claims 1 to 4, wherein there is a hydrophilic layer located between the waterproof and water vapor permeable membrane and the meltblown layer.

6. The waterproof and water vapor permeable footwear article according to claim 5, wherein the hydrophilic layer comprises an adhesive layer and / or a textile layer.

7. The waterproof and water vapor permeable footwear article according to any one of claims 1 to 6, wherein the meltblown layer comprises hydrophobic filaments, optionally elastic hydrophobic filaments.

8. The waterproof and water vapor permeable footwear article according to any one of claims 1 to 4, wherein the meltblown layer comprises polyurethane filaments or polyamide filaments, optionally thermoplastic polyurethane filaments.

9. The footwear article according to any one of claims 1 to 8, wherein the meltblown layer comprises filaments with a medium diameter of from 0.5 to 30 pm.

10. The footwear article according to any one of claims 1 to 9, wherein the areal weight of the meltblown layer is from 10 to 70 gsm.11 . Use of a laminate comprising a waterproof and water vapour permeable membrane and a meltblown layer for preventing or reducing wicking.

12. The use of a laminate of claim 11 , wherein the laminate is used in the upper of a waterproof and water vapor permeable footwear article.

13. The use of a laminate according to claim 12, wherein the meltblown layer is facing towards the outside of the waterproof and water vapor permeable footwear article.

14. The use of a laminate according to any one of claims 11 to 13, wherein the laminate further comprises an inner layer that is laminated to the surface of the waterproof and water vapour permeable membrane that is opposite to the meltblown layer.

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