Patent Application
20130055591
The invention relates to footwear with an upper, which is constructed with an outer material and a waterproof functional layer arranged on the inner side of the outer material, an outer-material end region on the sole side being joined to an inner sole and a functional-layer end region on the sole side being sealed by a sealing material leading to waterproofness. An example of footwear of this type is known from the applicant's EP 0 298 360 B1.
The invention also relates to a method for producing footwear of this type.
In the case of the footwear according to EP 0 298 360 B1, the outer-material end region ends at a predetermined distance from an inner sole serving as an insole, this distance being bridged by a gauze strip through which liquid material can flow, one longitudinal side of which is sewn to the outer-material end region and the other longitudinal side of which is sewn to the insole. One end of the functional layer on the sole side reaches down as far as the insole and is likewise sewn to the latter. This known footwear has a moulded-on outsole. When the outsole is being moulded on, the gauze strip is penetrated by liquid outsole material, whereby such outsole material flows against the outer side of the functional layer and, after curing, brings about waterproof sealing of the functional layer in the functional-layer end region.
With this so-called gauze-strip solution, which has proven to be very successful, particularly good and reliable waterproofness of breathable shoes has been accomplished.
The sewing of the gauze strip on its two longitudinal sides requires a certain effort, with corresponding consequent costs. What is more, at points at which the insole has a small radius of curvature, in particular in the case of children's shoes, it is not always that easy to sew the gauze strip without any folds.
The present invention provides footwear with which such problems can be overcome, which is inexpensive, can be handled more easily during production, including at points with small radius of curvature, and leads to good waterproofness.
The invention provides footwear according to claim 1 which can be produced in a way corresponding to claim 19. Embodiments of the footwear according to the invention and of the method according to the invention are provided in the dependent claims.
Footwear according to the invention comprises an upper, which is constructed with an outer material having an outer-material end region on the sole side and with a waterproof functional layer which is arranged on the inner side of the outer material and has a functional-layer end region on the sole side. What is more, such footwear has an inner sole and a joining device which joins the outer-material end region to the inner sole, which runs around at least part of the periphery of the upper, and which allows for a space to be left between the outer-material end region and the inner sole in such a manner, that it can be flowed through by sealing material that is liquid during application. The functional-layer end region extends at least into the region of the joining device and is sealed in a waterproof manner by sealing material which has passed through the joining device during production of the footwear.
In the case of the method according to the invention, footwear of the stated type is produced by the outer-material end region being joined to the inner sole by means of a joining device running around at least part of the periphery of the upper, in such a way that a space through which liquid can flow can be established between the outer-material end region and the inner sole, that the functional-layer end region is designed in such a way that it extends at least into the region of the joining device, and that, while the outer-material end region and the inner sole are kept at a distance from each other by means of the joining device, which can be flowed through by liquid, a sealing material which is in the liquid state and leads to waterproofness is applied to the outer side of the joining device in such a way that it flows through the liquid-permeable joining device against the functional-layer end region.
The functional-layer end region is formed in such a way that the sealing material flows against a surface-area region of the functional layer, just a cut edge of the functional layer or both.
In the case of one embodiment of the invention, a lining is arranged on the inner side of the functional layer, the lining being either a separate lining layer or a lining layer joined to the functional layer to form a laminate.
In embodiments of the invention, the inner sole is an insole or some other material which closes off the upper at its end on the sole side, for example an intermediate sole or a sealing sheet (gasket).
In one embodiment of the invention, the joining device is formed by a joining device which is like or similar to a seam.
In one embodiment of the invention, the joining device is formed by an expandable seam, which is either loosely sewn, so that it can be flowed through by liquid sealing material at least in a stretched or extended state, or which is sewn with an extensible yarn, so that the outer-material end region on the sole side and the inner sole can be brought to such a distance from each other during the production of the footwear by extending the yarn that liquid sealing material can flow through the extended seam. The extensible yarn may be elastically extensible yarn or non-elastically extensible yarn.
In one embodiment of the invention, the joining device is formed by a Strobel seam, which is either loosely sewn or sewn with extensible yarn. However, other types of seams, for example a quilted seam or a cross seam, which are loosely sewn or sewn with extensible yarn, are also suitable.
However, a joining device according to the invention does not have to be formed by a sewn seam. Other types of joining devices are also suitable, as long as they only form a connection between the outer material and the inner sole through which liquid material can flow. Examples of joining devices which are not sewn but are suitable for the invention are adhesive filaments or adhesive strips, which are adhesively attached to the outer material and to the inner sole, loops or individual rings, which are joined to the outer material and to the inner sole, or staple like joining elements, which are joined to the outer material and to the inner sole.
In the case of footwear with a joining device according to the invention, in the form of a seam, only a single joining seam is required in the region of the connection between the outer material and the inner sole, said joining seam also being entirely unproblematical even at those points at which the inner sole has a small radius of curvature. All that is required in comparison with footwear with a conventional seam, as shown for example in
In the case of a joining device according to the invention in the form of a sewn seam, this means that the sewing machine used for producing the seam merely needs to be set in such a way that it creates a seam which can be flowed through by liquid material, or that extensible yarn is sewn with a conventional sewing machine st at a conventional setting and this yarn is extended by liquid sealing material being applied, in such a way that the liquid sealing material can flow against the said zone of the functional layer through the extended seam.
A seam according to the invention accordingly does not entail any greater effort than that which is required for a conventional seam, for example for the prior-art footwear shown in
In the case of one embodiment of the invention, the functional-layer end region on the sole side is adhesively bonded to the inner sole.
In the case of one embodiment of the invention, a substantially nonexpandable fixed seam, by means of which the functional-layer end region on the sole side is joined to the inner sole, but not to the outer-material end region on the sole side, is provided in addition to the joining device.
In the case of one embodiment of the invention, the fixed seam is formed by a Strobel seam.
In the case of one embodiment of the invention, the outer material ends at a predetermined distance above the inner sole, the distance between the outer material and the inner sole is bridged by a strip of material impermeable to sealing material or liquid sole material, the strip of material is joined to the outer material by means of a top seam and to the functional layer and/or to the inner sole by means of a bottom seam and at least the top one of the two seams forms a joining device which can be flowed through, in the form of a seam which can expand as a result of loose sewing or sewing with an extensible yarn.
The sealing material may be either sole material, in particular outsole material of a moulded-on outsole, or a sealing adhesive which is liquid during application or can be liquefied after application by being activated. In one embodiment of the invention, a reactive hot-melt adhesive which in the fully reacted state leads to particularly high and permanent waterproofness of the sealed spot is used as the sealing adhesive.
Reactive hot-melt adhesive has, on the one hand, particularly great creepability in the liquid state before fully reacting and, on the other hand, brings about particularly high and permanent waterproofness in the fully reacted state. The reactive hot-melt adhesive can be applied with very simple means, for example be brushed on, sprayed on or applied in the form of a strip of adhesive or a bead of adhesive, the reactive hot-melt adhesive being made tacky by heating and, as a result, allowing itself to be attached to the region to be sealed before the full reacting process and accompanying permanent adhesive bonding to the functional layer begins.
The adhesive bonding of the reactive hot-melt adhesive or other sealing material to the functional layer is particularly intimate if the reactive hot-melt adhesive or other sealing material is mechanically pressed against the functional layer after being applied to the joining strip. Preferably suitable for this purpose is a pressing device, for example in the form of a pressing pad, with a smooth material surface which cannot be wetted by the reactive hot-melt adhesive or other sealing material and therefore cannot bond with the reactive hot-melt adhesive or the other sealing material, for example made of non-porous polytetrafluoroethylene (also known by the trade name Teflon), silicone or PE (polyethylene). Preferably used for this purpose is a pressing pad, for example in the form of a rubber pad or air cushion, the pressing surface of which is covered with a film of one of the said materials, for example non-porous polytetrafluoroethylene, or such a film is arranged between the sole construction provided with the reactive hot-melt adhesive or the other sealing material and the pressing pad before the pressing operation.
Preferably, a reactive hot-melt adhesive which can be cured by means of moisture is used, which adhesive is applied to the region to be adhesively bonded and exposed to moisture to make it fully react. In one embodiment of the invention, a reactive hot-melt adhesive which can be thermally activated and can be cured by means of moisture is used, which adhesive is thermally activated, applied to the region to be adhesively bonded and exposed to moisture to make it fully react.
Reactive hot-melt adhesives refer to adhesives which, before their activation, comprise relatively short molecular chains with an average molecular weight in the range from approximately 3000 to approximately 5000 g/mol, are non-adhesive and, possibly by thermal activation, are brought into a state of reaction in which the relatively short molecular chains are crosslinked to form long molecular chains and thereby cure, doing so predominantly in moist atmosphere. During the reaction or curing time, they are capable of adhesive bonding. After the crosslinking curing, they cannot be re-activated. When they fully react, three-dimensional crosslinking of molecular chains occurs. The three-dimensional crosslinking leads to particularly high protection against water ingress into the adhesive.
Suitable for example for the purpose according to the invention are polyurethane reactive hot-melt adhesives, resins, aromatic hydrocarbon resins, aliphatic hydrocarbon resins and condensation resins, for example in the form of epoxy resin.
Particularly preferred are polyurethane reactive hot-melt adhesives, referred to hereafter as PU reactive hot-melt adhesives.
In one practical embodiment of footwear according to the invention, a PU reactive hot-melt adhesive which is obtainable under the name IPATHERM S 14/242 from the company H. P. Fuller of Wells, Austria, is used. In another embodiment of the invention, a PU reactive hot-melt adhesive which is obtainable under the name Macroplast QR 6202 from the company Henkel AG, Dusseldorf, Germany, is used.
In one embodiment, in which the joining device according to the invention is formed by a sewn seam, monofilament sewing yarn is used, which yarn has a comparatively small yarn diameter in comparison with multi-filament sewing yarn, so that liquid sealing material flows against a greater surface area of the functional-layer zone located in the region of the joining device than in the case of multi-filament sewing yarn with a larger yarn diameter. What is more, in the case of mono-filament sewing yarn, there is no longer the risk that exists in the case of multi-filament sewing yarn of water being conducted along the sewing yarn as a consequence of capillary action.
Sewing machines by means of which a joining seam according to the invention can be produced by loose sewing are obtainable under the name Strobel machines from the company Strobel of Munich, Germany.
Monofilament sewing yarn, which is well suited for the production of a joining device according to the invention, is obtainable under the name Transfil from the company Amann & Söhne GmbH & Co. KG, D-74357 Bönnigheim, Germany. Extensible yarn which is suitable for a joining device according to the invention is a thread which is obtainable from the stated company Amann under the name Serafil 40/3 and has a non-destructive extensibility of 25%.
In one embodiment of the invention, a functional layer which is not only water-impermeable but also water-vapour-permeable is used This makes it possible to produce waterproof shoes which remain breathable in spite of the waterproofness.
Suitable materials for the waterproof, water-vapour-permeable functional layer are, in particular, polyurethane, polypropylene and polyester, including polyether esters and their laminates, as described in the publications U.S. Pat. No. 4,725,481 and U.S. Pat No. 4,493,870. Particularly preferred, however, is expanded microporous polytetrafluoroethylene (ePTFE), as described for example in the publications U.S. Pat. No. 3,953,566 and U.S. Pat. No. 4,187,390, and expanded polytetrafluoroethylene which is provided with hydrophilic impregnating agents and/or hydrophilic layers; see for example the publication U.S. Pat. No. 4,194,041. A microporous functional layer is understood to mean a functional layer of which the average pore size lies between approximately 0.2 microns and approximately 0.3 microns.
The pore size can be measured with the Coulter Parameter (trade name), which is produced by Coulter Electronics, Inc., Hialeath, Fla., USA.
A functional layer is regarded as “waterproof”, if appropriate including the seams provided at the functional layer, if it ensures a water ingress pressure of at least 1×104 Pa. The material of the functional layer preferably ensures a water ingress pressure of over 1×105 Pa. The water ingress pressure is measured by a test method in which distilled water at 20±2° C. is applied with increasing pressure to a sample of the functional layer of 100 cm2. The pressure increase of the water is 60±3 cm of water column per minute. The water ingress pressure then corresponds to the pressure at which water appears on the other side of the sample for the first time. Details of the procedure are described in ISO standard 0811 from the year 1981.
A functional layer is regarded as “water-vapour-permeable” if it has a water-vapour permeability coefficient Ret of less than 150 m2×Pa×W−1. The water-vapour permeability is tested by the Hohenstein skin model. This test method is described in DIN EN 31092 (February 1994) or ISO 11092 (1993).
Whether a shoe is waterproof can be tested for example by a centrifuge arrangement of the type described in U.S. Pat. No. 5,329,807.
If ePTFE is used as the functional layer, the reactive hot-melt adhesive can penetrate into the pores of this functional layer during the cementing operation, which leads to a mechanical anchoring of the reactive hot-melt adhesive in this functional layer. The functional layer consisting of ePTFE may be provided with a thin polyurethane layer on the side with which it comes into contact with the reactive hot-melt adhesive during the cementing operation. If PU reactive hot-melt adhesive is used in conjunction with such a functional layer, there occurs not only the mechanical bond but also a chemical bond between the PU reactive hot-melt adhesive and the PU layer on the functional layer. This leads to a particularly intimate adhesive bonding between the functional layer and the reactive hot-melt adhesive, so that particularly durable waterproofness is ensured.
The extension of the end of the functional layer on the sole side in relation to the end of the outer material on the sole side and/or the inner sole can be adapted to the requirements of the respective specific footwear. For the functioning of the invention, it is merely required that the end of the functional layer on the sole side extends at least into the region of the joining device, so that sealing material flowing through the joining device can impinge on the functional layer and seal it.
The minimum length which the joining device is to have or the minimum space which the joining device has to allow for during the application of liquid sealing material depends on the viscosity of the liquid sealing material and on the pressure at which the liquid sealing material is applied. The lower the viscosity and the higher the pressure, the smaller this length/space can be. In embodiments of the invention, the distance between the end of the outer material and the inner sole which the joining device has or allows lies in the range from approximately 1/10 mm to approximately 12 mm. In practical embodiments, the distance between the end of the outer material and the inner sole lies in the range from 1 mm to 6 mm, in a more narrowly specified case between 1 mm and 4 mm. In the case of sealing material which has a particularly low viscosity in the liquid state and which is sprayed on with relatively high pressure, a length of the joining unit which lies below 2 mm, and is for example in the range from 0.1 mm to 1 mm, may be adequate. Since it is adequate for the flow to take place against a relatively small surface area of the functional layer in order to seal it with the sealing material, in many practical embodiments the length which the joining device has or the space to be allowed for need not be very much more than 2 mm. A much greater length/space, for example in the range from 4 to 5 mm or higher, is only desirable, if at all, if sealing material which has a comparatively high viscosity in the liquid state is applied with low pressure.
Leather or textile fabrics are suitable for example as the outer material of the upper. The textile fabrics may be, for example, woven or knitted fabrics, non-wovens or felt. These textile fabrics may be produced from natural fibres, for example from cotton or viscose, from synthetic fibres, for example from polyesters, polyamides, polypropylenes or polyolefins, or from blends of at least two such materials.
When a functional layer is used, a lining material is normally arranged on the inner side. The same materials as are specified above for the textile outer material of the upper are suitable as lining material, which is often combined with the functional layer to form a functional-layer laminate. The functional-layer laminate may also have more than two layers, it being possible for a textile backing to be located on the side of the functional layer remote from the lining layer.
The outsole of footwear according to the invention may consist of waterproof material, such as for example rubber or plastic, for example polyurethane, or of non-waterproof, but breathable material, such as in particular leather, leather provided with rubber or plastic inlays or rubber or plastic provided with leather inlays. In the case of non-waterproof outsole material, the outsole can be made waterproof, while maintaining breathability, by being provided with a waterproof, water-vapour-permeable functional layer at least at points at which the sole construction has not already been made waterproof by other measures.
In the case of a moulded-on sole, for example an outsole, being also used as sealing material, it may consist for example of polyurethane (PU).
The insole of footwear according to the invention may consist of viscose, a nonwoven, for example polyester nonwoven, to which fusible fibres may be added, leather or adhesively bonded leather fibres. An insole is obtainable under the name Texan Brandsohle from Texon Mockmuhl GmbH of Mockmuhl, Germany. Insoles of such materials are water-permeable. An insole of such material or other material can be made waterproof by arranging a layer of waterproof material on one of its surfaces or inside it. For this purpose, for example, a film with Kappenstoff V25 from the company Rhenoflex of Ludwigshafen, Germany, may be ironed on. If the insole is to be not only waterproof but also water-vapour-permeable, it is provided with a waterproof, water vapour-permeable functional layer, which is preferably constructed with ePTFE (expanded, microporous polytetrafluoroethylene). Suitable for this for example is a laminate which contains a waterproof, water-vapour-permeable functional layer and is obtainable under the trade name TOP DRY from W.L. Gore & Associates GmbH, Putzbrunn, Germany.
A further possibility is to adhesively attach such a laminate (TOP DRY) onto the insole, whereby the upper is already made waterproof before an outsole is applied.
The invention is now explained in more detail on the basis of embodiments. In the drawings, in which part of a shoe, for example in the region of the front foot of the shoe, is depicted as highly schematized representations which are not true to scale:
All the figures show a greatly schematized sectional view, in each case of part of a not yet completed shoe in a cross section in the forefoot region. For all of the embodiments production phases before the shoe has been stretched onto a last and production phases after the shoe has been stretched onto a last are shown in the figures. The word shoe is used here, although this shoe has not yet been fully completed, since, with the exception of the representation in
Shown in
Shown in
The sealing material, applied only in the region of the gap 33 in the case of
In order to obtain sealing of the functional layer 19 in the end region 23 on the sole side, it is neither necessary for the functional-layer free zone 35 to extend over the entire gap 33 nor necessary for the end 23 of the functional layer on the sole side to extend beyond the gap 33. To achieve adequate sealing of the functional layer 19, it is adequate for the end 23 of the functional layer to extend into the gap 33. It is already adequate if the lower end 23 of the functional layer extends into the gap 33 only so far that a cut edge of the lower end 23 of the functional layer is located within the gap 33, so that sealing material can flow against and around this cut edge.
A second embodiment of the invention is now considered on the basis of
The second embodiment according to
Footwear exists in which the lower end of the outer material 17 on the sole side ends at a distance above the inner sole and this distance is bridged by a strip of impermeable material. In
In one embodiment of the invention, the joining device, in the embodiments represented in the figures the Strobel seam 25 or the Strobel seams 25, 25a, 25a, 26, runs around the entire lower periphery of the upper. In other embodiments of the invention, the joining device runs only around part of the periphery of the upper, while a different technology is used for the remaining part of the lower periphery of the upper. For example, the joining device according to the invention is provided only at those points of the periphery of the upper at which the periphery of the upper has a particularly small radius of curvature, as is the case in particular in the region of the toes and heels of shoes, most particularly in the case of children's shoes. As an example of another technology which can be used in the remaining region of the periphery of the upper, bootie technology may be mentioned. A bootie is the name given to a sock-like insert which includes a waterproof and water-vapour-permeable functional layer and is arranged as a lining on the inner side of the upper and of the sole construction. When bootie technology is applied in the case of a shoe in which a joining device according to the invention is used in a subregion of the periphery of the upper, only the remaining region of the periphery of the upper is provided with a bootie-like formation.
In the embodiments represented in the figures, the Strobel seam 25 or the Strobel seams 25a, 25a are made flow-through by the said seam or seams being loosely sewn. As already mentioned, in other embodiments of the invention flowing through of the seam or seams is accomplished by the said seam or seams being sewn with extensible yarn. The same effects are obtained when using, for example, a lockstitch seam or zigzag seam sewn loosely or with extensible yarn.
| Number | Date | Country | Kind |
|---|---|---|---|
| 10321491.7 | May 2003 | DE | national |
| PCT/EP04/04781 | May 2004 | EP | regional |
The present application is a continuation application of pending U.S. patent application Ser. No. 10/555,146 filed Oct. 31, 2005.
| Number | Date | Country | |
|---|---|---|---|
| Parent | 10555146 | Nov 2006 | US |
| Child | 13617452 | US |
