FOOTWEAR WITH LAST AREA SEALING AND METHOD FOR ITS PRODUCTION

Abstract

Footwear is described that has an insole with an insole bottom; an upper which is constructed with an outer material and which has an end region on the sole side; and a waterproof upper functional layer, which lines at least partially the outer material on its inside and also has an end region on the sole side. The upper has a lasting margin area, in which the end region of the upper is adhered to the insole bottom by means of a lasting adhesive. An outsole is adhered to the lasting area bottom by means of an outsole adhesive. The lasting adhesive is a waterproof reactive hot melt adhesive.

Description

FIELD OF THE INVENTION

[0001] The invention concerns footwear with an upper lasted on the bottom of an insole, which is provided at least partially with a waterproof functional layer from a sheet-like material, which is preferably water vapor-permeable, and with an outsole adhered to the bottom of the last area. The invention also concerns a method for production of such a shoe.

BACKGROUND OF THE INVENTION

[0002] There are shoes whose shoe upper is waterproof and water vapor-permeable because of lining with a functional layer that provides both functions. This type of shoe upper remains breathable, i.e., water-vapor-permeable, despite being waterproof. Special efforts are required in order to ensure long-lasting waterproofness in the region between the end of the upper on the sole side and the sole structure itself.

[0003] In shoes that are produced with the known lasting process, the shoe upper is adhered onto the bottom of the insole along an edge region of the insole called the lasting margin, and an outsole is applied to the bottom of this adhered unit. Weak points are present in this construction. In particular, creases of the lasted upper material formed in the last margin area at the sites on which the shoe contour has a small radius of curvature are weak, since the lasting adhesive either from the outset does not seal the entire transitional region between the shoe upper and the insole, especially in the region of the lasting folds, or can become worn and thus water-permeable by bending stresses during shoe use.

[0004] It is known from DE 40 00 156A that sealing adhesives can be arranged between the periphery of the insole and the functional layer of the upper. To prevent water that reaches the bottom of the insole via the outer material of the upper and in the lasting margin from reaching the shoe interior, the insole is provided with a waterproof insole layer. There can be instances in which the additional step of adhering the insole periphery to the functional layer and the use of the waterproof insole are not desired.

[0005] A method for sealing a shoe upper provided with a waterproof and a water vapor-permeable functional layer is known from EP 0 286 853A, in which an inner edge region of the last area is kept unsealed during lasting and an injection mold with a protruding sealing lip is applied to the bottom of the last area after the lasting process. In this case the sealing lip essentially follows the contour of the insole edge and is displaced somewhat toward the insole center relative to the outer peripheral contour of the outsole to be applied later. A sealing material is injected into the space formed between the sealing lips, which encloses the edge region of the upper provided with the functional layer left unsealed during lasting and thus seals it. This sealing process has proven itself, but requires an injection mold and an injection machine of the mentioned type.

[0006] It was known from EP 0 595 941B that the last margin area can be sealed in a shoe with an upper that has a waterproof layer and is lasted around an insole by embedding the edge of the upper region to be lasted in a waterproof material before lasting takes place, in which this material can be polyurethane (PU). This sealing method requires the additional process step of embedding the edge of the upper in the lasting margin region.

SUMMARY OF THE INVENTION

[0007] Footwear produced according to invention is provided which can be made permanently waterproof with the least possible machine expenditure and with the fewest possible process steps in the last margin region.

[0008] The footwear of the invention is footwear comprising:

[0009] a) an insole with an insole bottom;

[0010] b) an upper which is constructed with an outer material and has an end region on the sole side;

[0011] c) a waterproof upper functional layer, which forms a part of the upper and at least partially lines the outer material of the upper on its inside, particularly in the end region of the upper;

[0012] d) in which the upper has an end region in the lasting margin area which is adhered to the insole bottom by means of a lasting adhesive;

[0013] e) and an outsole which is adhered to the bottom of the lasted margin area;

[0014] f) wherein the lasting adhesive is a reactive hot melt adhesive which is waterproof in the reacted state.

[0015] The desired waterproofness in the lasting margin region is achieved in the method according to the invention in that a reactive hot-melt adhesive is used as lasting adhesive, an adhesive that adheres the upper end region to the bottom of the insole around the insole periphery, which leads to waterproofness in the cured or reacted state.

[0016] The use of a reactive-hot melt adhesive that cures to form a waterproof material as the lasting adhesive, prevents water that reaches the last margin region via the water-conducting outer material of the upper from reaching the inside of the functional layer that faces away from the outer material, and thus from reaching the shoe interior. This hazard is particularly high when a liner material with high absorption capacity is situated on the inside of the functional layer. The reactive hot melt adhesive used according to the invention as lasting adhesive seals the materials in the lasting region reliably and permanently waterproof, including the particularly critical last crease areas, even after bending stress during walking with the footwear.

BRIEF DESCRIPTION OF THE DRAWINGS

[0017] FIG. 1 schematically depicts a shoe structure of a first variant of the invention after application of the lasting adhesive;

[0018] FIG. 2 schematically depicts an enlargement of a section of the upper shoe structure;

[0019] FIG. 3 schematically depicts a shoe structure of the type depicted in FIG. 1 after lasting;

[0020] FIG. 4 schematically depicts a shoe structure of the type depicted in FIG. 3 after application of outsole adhesive;

[0021] FIG. 5 schematically depicts a shoe structure of the type depicted in FIG. 4 after adhering of an outsole;

[0022] FIG. 6 schematically depicts a portion of the shoe structure depicted in FIG. 5 with indications explaining waterproofness;

[0023] FIG. 7 schematically depicts the shoe structure of a second variant of the invention;

[0024] FIG. 8 schematically depicts the shoe structure of a third variant of the invention after application of the lasting adhesive;

[0025] FIG. 9 schematically depicts the shoe structure depicted in FIG. 8 after lasting;

[0026] FIG. 10 schematically depicts the shoe structure depicted in FIG. 9 after application of the outsole adhesive;

[0027] FIG. 11 schematically depicts the shoe structure depicted in FIG. 10 after adhering of an outsole; and

[0028] FIG. 12 schematically depicts an enlarged two-dimensional view of the reacted reactive hot melt adhesive by three-dimensional crosslinking of the molecular chains.

DETAILED DESCRIPTION OF THE INVENTION

[0029] In one variant of the invention, a reactive hot melt adhesive is used both as the lasting adhesive and as outsole adhesive. In this case the reactive hot melt adhesive is initially applied to the lasting region, and then the same or another reactive hot melt adhesive is later applied to the bottom of the lasted region after the lasting process, in order to adhere the outsole to said bottom. The reactive hot melt adhesive serving as lasting adhesive and the reactive hot melt adhesive serving as outsole adhesive can be applied so that they are joined together to form an adhesive enclosure that envelopes or encloses in waterproof fashion the end region on the sole side on both the outer material of the upper and the upper functional layer. This leads to an increased sealing function, as will be further explained below.

[0030] During production of the footwear in which the reactive hot melt adhesive serves also as the outsole adhesive, the adhesive can be applied early enough after application of the reactive hot melt adhesive serving as the lasting adhesive, so that lasting adhesive is still reactive and the outsole adhesive can be bonded to the lasting adhesive by chemical bonding into a common, uniform enclosure.

[0031] The outsole adhesive, however, can also be applied after curing of the lasting adhesive or after curing of the lasting adhesive at least on its free surface. In this instance, a mechanical bond is formed between the two, which exhibits mechanical strength as well as waterproofness.

[0032] Footwear according to the invention comprises an insole with an insole bottom; an upper, which is constructed with an outer material and has an end region on the sole side; a waterproof upper functional layer which forms part of the upper and which lines at least partially the outer material of the upper on its inside. The upper has an end region on the sole side which is the lasting margin that is adhered to the insole bottom by means of a reactive hot melt lasting adhesive. An outsole is adhered by an outsole adhesive to the bottom of the upper in the lasting margin that faces away from the insole bottom, by an outsole adhesive.

[0033] By functional layer is meant a layer that is liquid waterproof, and preferable also water vapor permeable.

[0034] Neither an injection mold nor an additional machine to introduce the sealing material is required in the production method according to the invention, nor is an additional sealing necessary between the peripheral edge of the insole and the functional layer, nor a process step in which the free end of the upper in the lasting area must be enclosed by means of a sealing material before the lasting process takes place. The method according to the invention therefore leads to low production costs for waterproof shoes, which could not be achieved with known methods.

[0035] Production of shoes according to the invention becomes particularly simple and economical when reactive hot melt adhesives that can be heat-activated and can be brought to the curing reaction by means of moisture, for example, water vapor, are used.

[0036] If one would like to use a reactive hot melt adhesive whose initial strength is too limited because of a physical setting time that lasts too long, thermoplastic fractions can be added to the reactive hot melt adhesive that have sufficiently short setting time and initially take over the adhesive function until the reactive hot melt adhesive has cured far enough that it exhibits adequate adhesive action. Thermoplastics are defined herein to mean nonreactive polymers. They can be added to reactive hot melt adhesives. Thermoplastic polyesters and thermoplastic polyurethanes are suitable as thermoplastics that can be added to the PU-reactive hot melt adhesive.

[0037] By reactive hot melt adhesive is meant an adhesive that reacts on heating to form a cured or crosslinked adhesive. For example, polyurethane reactive hot melt adhesives, aromatic hydrocarbon resins, aliphatic hydrocarbon resins and condensation resins, for example, in the form of epoxy resins (EP) are suitable for use in this invention. Polyurethane reactive hot melt adhesives, hereafter called PU-reactive hot melt adhesives, are particularly preferred.

[0038] The crosslinking reaction of the PU-reactive hot melt adhesive that causes curing is produced by moisture, for which atmospheric moisture is sufficient. There are blocked PU reactive hot melt adhesives whose crosslinking reaction can only begin after activation of the PU reactive hot melt adhesive by means of heat energy so that such hot melt adhesives can be stored in the open, i.e., in an environment with atmospheric moisture. On the other hand, there are unblocked PU reactive hot melt adhesives in which a crosslinking reaction occurs at room temperature if they are situated in an environment with atmospheric moisture. The latter hot melt adhesives must be stored protected from atmospheric moisture.

[0039] Both types of PU reactive hot melt adhesives are ordinarily available in the unreacted state in the form of rigid blocks. Before application to the areas being adhered the hot melt adhesive is heated in order to melt it and thus make it capable of being spread or applied. In the case of use of unblocked hot melt adhesive such heating must occur with exclusion of atmospheric moisture. When blocked hot melt adhesives are used this is not necessary, but it must be ensured that the heating temperature remains below the unblocking activation temperature.

[0040] In one variant of the invention a PU reactive hot melt adhesive is used that is constructed with blocked or capped isocyanate. To overcome isocyanate blocking and thus for activation of the reactive hot melt adhesive constructed with the blocked isocyanate, thermal activation must be carried out. Activation temperatures for such PU reactive hot melt adhesives lie in the range from about 70 to 170° C.

[0041] A PU reactive hot melt adhesive useful in the invention is available under the name Ipatherm S 14/242 from H. P. Fuller in Wells, Austria.

[0042] An upper functional layer that is not only water-impermeable, but also water vapor-permeable is particularly preferred. This permits production of waterproof shoes that remain breathable despite waterproofness.

[0043] A functional layer (optionally including the seams provided on the functional layer, is considered “waterproof” if it has a water penetration pressure of at least 0.13 bar. A functional layer material will preferably have a water penetration pressure of more than 1 bar. The water penetration pressure is measured according to a test method in which distilled water at 20±2° C. is applied to a 100 cm2 sample of the functional layer with increasing pressure. The pressure increase of the water is 60±1 cmH2O per minute. The water penetration pressure corresponds to the pressure at which water first appears on the other side of the sample. Details of the procedure are given in ISO standard 0811 from 1981.

[0044] A functional layer is considered “water vapor-permeable” if it has a water vapor permeability number Ret of less than 150 m2Pa.W−1. Water vapor permeability is tested according to the Hohenstein skin model. This test method is described in DIN EN 31092 (02(94)) or ISO 11092 (19/33).

[0045] The waterproofness of a shoe or boot can be tested with the centrifuge method according to U.S. Pat. No. 5,329,807. A centrifuge arrangement described there has four pivotable mounting baskets to hold footwear. Two or four shoes or boots can thus be tested simultaneously. In this centrifuge arrangement centrifugal forces are utilized, which are generated by rapid centrifuging of the footwear, to find water-permeable sites in the footwear. Before centrifuging water is filled into the internal space of the footwear. An absorbent material, like blotting paper or a paper towel, is arranged on the outside of the footwear. The centrifugal forces exert a pressure on the water filled into the footwear, which causes the water to reach the absorbent material if the footwear is water permeable.

[0046] In this type of waterproof test the water is initially filled into the footwear. In footwear with an outer material not having sufficient intrinsic rigidity, a rigid material is arranged in the interior space of the upper for stabilization in order to prevent collapse of the upper during centrifuging. Blotting paper or a paper towel on which the footwear being tested is placed is situated in each holding basket. The centrifuge is then rotated for a specified time. The centrifuge is then stopped and the blotting paper or paper towel examined to determine if it is moist. If it is moist, the tested footwear did not pass the waterproofness test. If it is dry, the tested footwear passed the test and is classified as waterproof.

[0047] The pressure that the water exerts during centrifuging depends on the active shoe surface which depends on shoe size (sole inside surface) A, on the weight m of the water filled into the footwear, on the affected centrifuge radius r and on the centrifuge speed U.

[0048] The water pressure exerted on the effective shoe surface by centrifuging is then:

P=(m.v2)/(A.r)=(m.&ohgr;2.r)/A

[0049] with &ohgr;=2&pgr;f and v=2r&pgr;f.

[0050] An effective centrifuge radius of 50 cm and a centrifuge speed of 254 rpm are used in a waterproofness test suitable for the footwear according to the invention. In footwear of shoe size 42 with an effective shoe surface of 232 cm2 the footwear is filled with a liter of water.

[0051] This gives:

m=1 kg

v=2.0.5m.&pgr;.4.23/s=13.3 m/s

P=(1 kg.(13.3 m/s)2)/(0.5 m.0.0232 m2)=353.8 N/0.0232 m2=0.13956 bar

[0052] For other shoe sizes with correspondingly different effective shoe surface an equivalent test pressure can be achieved with correspondingly altered amount of water.

[0053] Appropriate materials for the waterproof, water vapor-permeable functional layer include polyurethane, polypropylene and polyester, including polyether-ester and their laminates, as described in the documents U.S. Pat. Nos. 4,725,418 and 4,493,870. However, expanded porous polytetrafluoroethylene (ePTFE) is particularly preferred, as described in U.S. Pat. Nos. 3,953,566 and 4,187,390, and expanded polytetrafluoroethylene provided with water-vapor-permeable impregnation agents and/or layers; see, for example the document U.S. Pat. No. 4,194,041. A porous functional layer is understood to mean a functional layer whose average pore size lies between 0.2 micrometers and 0.3 micrometers.

[0054] The pore size can be measured with the Coulter Porometer (trade name) which is produced by Coulter Electronics, Inc., Hialeah, Fla., USA.

[0055] The Coulter Porometer is a measurement device that offers automatic measurement of the pore size distribution in porous media, in which the liquid displacement method is used (described in ASTM Standard E 1298-89).

[0056] The Coulter Porometer determines the pore size distribution of the sample by increasing air pressure directed on the sample and by measuring the resulting flow. This pore size distribution is a gauge of the degree of uniformity of the pores of the sample (i.e., a narrow pore size distribution means that there is a limited difference between the smallest pore size and the largest pore size). It is determined by dividing the maximum pore size by the minimum pore size.

[0057] The Coulter Porometer also calculates the pore size for average flow. By definition half of the flow occurs through the porous sample through pores whose pore size lies above or below this pore size for average flow.

[0058] If expanded porous polytetrafluoroethylene is used as the functional layer of the upper, the reactive hot melt adhesive can penetrate into the pores of the functional layer during the adhering process, which leads to mechanical anchoring of the reacted hot melt adhesive in the functional layer. The functional layer consisting of ePTFE can be provided with a thin water-vapor-permeable polyurethane layer on the side with which it comes in contact with the reacted hot melt adhesive during the cooling process. During use of PU reactive hot melt adhesives in conjunction with such a functional layer, not only does mechanical bonding occur, but so does chemical bonding between the PU reactive hot melt adhesive and the PU layer of the functional layer. This leads to particularly intimate adherence between the functional layer and the reactive hot melt adhesive so that a particularly long-lasting waterproofness is guaranteed.

[0059] A waterproof outsole and/or a waterproof insole can be used. However, if breathability is to be maintained in the sole region despite waterproofness, an insole and an outsole that consists at least in partial regions of water and water vapor-permeable material can be used and the waterproofness ensured by providing the water-permeable regions of the insole and/or outsole with a waterproof, water vapor-permeable sole functional layer.

[0060] In a preferred aspect, the insole can consist of a water-permeable material and the outsole can be constructed with leather within a peripheral edge consisting of rubber or plastic, on whose side facing the insole a waterproof, water vapor-permeable sole functional layer is arranged. This extends in a direction toward the sole periphery at least far enough so that it is overlapped by the region of the last margin enclosed with the reactive hot melt adhesive.

[0061] A shoe according to the invention can be constructed with an outer material upper and an upper functional layer that lines the inside of the outer material. The functional layer is preferably part of a laminate that has the functional layer and at least one liner layer facing the shoe interior. The laminate can also have more than two layers, in which a textile backing can be situated on the side of the functional layer facing away from the liner layer. A last region is formed for both the outer material upper and for the functional layer upper. Adhesive lasting of the last region can then be produced in a single adhesive lasting process or in two separate lasting processes, each with a reactive hot melt adhesive as lasting adhesive.

[0062] If two separate adhesive lasting processes are carried out for lasting of the outer material of the upper and for lasting of the functional layer of the upper, these two lasting processes and the subsequent outsole adhering process can be conducted in a time frame so that the crosslinking or curing process for the reactive hot melt adhesive applied for the first lasting process is still not far advanced enough that it still can be adequately bonded chemically to the reactive hot melt adhesive applied as outsole adhesive in order to be able to form together a waterproof enclosure for the two last regions.

[0063] A cavity can be formed within the last area edge between the insole and outsole, which is ordinarily filled with a filler. This filler can be any of the known ordinary filler materials in a shoe according to the invention. However, this cavity can also be filled with reactive hot melt adhesive.

[0064] The reactive hot melt adhesive used as lasting adhesive is preferably introduced in paste-like, for example, bead-like form, at the an angle formed between the lower peripheral edge of the insole and the upper part being lasted, protruding above the edge of the insole before lasting. The reactive hot melt adhesive serving as outsole adhesive is preferably sprayed onto the bottom of the last margin area.

[0065] If thermoplastic fractions are admixed with the reactive hot melt adhesive and the resulting mixture exhibits sufficient and temporary adhesive capability for the correct time because of the admixed thermoplastic hot melt adhesive, one can proceed so that the adhesive serving as lasting adhesive is applied first. The lasted upper is temporarily adhered to the insole with its temporary adhesive capability. The outsole adhesive is applied to the bottom of the lasted area and the outsole then fastened to the bottom of the lasted area temporarily under the temporary adhesive action of the thermoplastic adhesive. The crosslinking reaction leading to curing under the influence of atmospheric moisture or water vapor and, in the case in which a block reactive hot melt adhesive is used, its thermal activation that proceeds the crosslinking reaction, can then be carried out in a common step.

[0066] Adhesives that consist, before activation, of relatively short molecular chains with an average molecular weight in the range from 3000 to 5000 g/mol, are nonadhesive and are optionally brought to a state of reaction after thermal activation in which the relatively short molecular chains crosslink to long molecular chains and then cure in a moist atmosphere. They are capable of adhesion in the reaction or curing period. After crosslinking curing they cannot be reactivated. The curing reaction leads to three-dimensional crosslinking of the molecular chains, which causes waterproofness of the cured reactive hot melt adhesive.

[0067] A first practical example of the shoe according to the invention is explained with reference to FIGS. 1 to 3. These show such a shoe in a very schematized fashion in different production phases.

[0068] The shoe according to this first practical example has a waterproof insole 11, which is arranged on a last 13. The insole 11 is situated within an upper 15, which is constructed with a water-permeable outer material 17, for example, leather or textile material. The inside of outer material 17 is lined with a functional layer laminate 19, which has an upper functional layer 21 and is further explained in conjunction with FIG. 2. In this phase of production the upper 15 is already pulled over the last 13 and the insole 11, in which the end region of the upper on the sole side, which later forms the last margin, still protrudes above the bottom of the insole 23. An angle in which the reactive hot melt adhesive serving as lasting adhesive 25 is applied is formed between the peripheral edge region of the insole bottom 23 and the end region of upper 15 on the sole side. However, this is not a necessity for functioning of the gluing according to the invention. It is only important that the hot melt adhesive be applied so that after the lasting process it is present between the insole bottom 23 and the lasted part of the functional layer laminate 19 in the form of a strip of adhesive continuous in the peripheral direction of the insole. This adhesive strip can extend over the entire width of the lasted part of the functional layer laminate 19 or only over a part of the width of this lasted part of the functional layer laminate. The lasting adhesive is preferably applied so that it comes to lie in the region of the lasted area connected to the peripheral edge of the insole after the lasting process. This region is ordinarily free of lasting creases, which only occur at a certain spacing of, say, 5 to 10 mm, from the peripheral edge of the insole, especially at the site where the shoe contour has a strong curvature.

[0069] If a lasting adhesive that is sufficiently capable of creep in the still unreacted viscous state is used in order to be able to penetrate adequately between the lasting creases so that the lasting creases are sealed by the lasting adhesive, one can also restrict oneself to providing the lasting adhesive only in that width region of the last margin area in which lasting creases can form.

[0070] The lasting adhesive 25 is preferably applied in the form of paste, for example, by means of a nozzle (not shown) that ejects an adhesive bead. The triangular shape in the lasting adhesive 25 is only to be interpreted schematically in FIG. 1. The adhesive bead can have any other desired cross section.

[0071] FIG. 2 shows a section (rotated by 90°) from the upper structure 15 after preparation for adhesive lasting. On the outside of the upper, which is situated on the bottom in FIG. 2, a section of the leather that serves as outer material 17 can be seen. On its inside, on the top in FIG. 2, the functional layer laminate 19 is situated. The upper functional layer 21 is made of ePTFE. A textile backing 27 is situated on the outside of the upper functional layer 21 facing the outer material 17 in the form of knitted or mesh material which serves for mechanical support of the upper functional layer 21. The upper functional layer 21 is provided with a PU layer 29 on the inside facing away from outer material 17. The upper functional layer 21 with a PU layer 29 can be produced according to the instructions of U.S. Pat. No. 5,026,591 (Henn), but is not restricted to this. An additional layer 31 is situated on its inside. This can be a nonwoven textile layer, a plastic foam layer, a nonwoven layer or a leather layer. A textile sealing layer 33 is situated on the inside of the additional layer 31. A functional layer laminate 19 of the type depicted in FIG. 2 is known.

[0072] In the usual functional layer laminate the additional layer 31 is thick so that it cannot be penetrated by the adhesive or not sufficiently penetrated. In order to enable the lasting adhesive 25 to penetrate up to the upper functional layer 21 it is known that the additional layer 31, if it consists of a nonwoven textile layer or a foam layer, and the textile sealing layer 33 are applied by a skiving process in that region in which gluing of the reactive hot melt adhesive lasting adhesive 25 to the upper functional layer or its PU layer 29 (if present) is to occur. In the case of an additional layer 31 in the form of leather the upper functional layer 21 can be left free in the region of the leather layer being adhered.

[0073] The skiving process can be carried out by means of a skiving machine known in shoe manufacture, for example, by means of the machine Fortuna S4 from the Fortuna Co., Germany.

[0074] Returning to FIG. 1, it is apparent that the upper functional layer 21 and the backing 27 extend downward above the lasting adhesive 25, whereas the nonwoven textile layer 31 and the textile closure layer 33 stop roughly at the bottom of the insole 23 as a result of the skiving conducted as shown in FIG. 2. The upper functional layer 21 with its PU layer 29 is therefore exposed in the region extending above the bottom of the insole 23 and can come into direct adhesive contact with the lasting adhesive 25 because of this.

[0075] A production phase is shown in FIG. 3 in which the last region 35 of the upper 15 is lasted around the last 13 and the insole 11. In the lasting step conducted in this manner the bead-like lasting adhesive 25 was formed to a flat lasting layer 37. The bead of lasting adhesive 25 applied in the production phase according to FIG. 1 was dimensioned so that the lasting adhesive layer 37 extends beyond the center of the insole above the inner last insert edge 39. As is readily apparent in FIG. 3, the cutting edge 36 facing the center of the insole and its pared end region 41 facing the bottom of the insole 23 are enclosed by the adhesive lasting material. The shoe structure depicted in FIG. 3 lacks only an outsole for completion.

[0076] By using a lasting adhesive that is waterproof, water that penetrates along the outer material of the upper to the end of the lasted region 35 on the outsole side, cannot reach the inside of the region of the upper functional layer 21 folded under the insole 11 and therefore cannot reach the shoe interior.

[0077] A modification of the first variant of the invention is now explained with reference to FIGS. 4 to 6, whose production begins with the production steps according to FIGS. 1 to 3.

[0078] In conjunction with the production steps according to FIGS. 1 to 3 reactive hot melt adhesive serving as outsole adhesive 45 is applied to the bottom of the lasted portion 43. This application can occur either by coating not only the bottom of the lasted portion 43 but also the region of the bottom of the insole 23 left free of lasting adhesive with outsole adhesive 45, as shown in FIG. 5 or by leaving a center region of the bottom of insole 23 free of outsole adhesive, as shown in FIG. 4. The variant depicted in FIG. 5 is recommended when an outsole that is not waterproof itself is adhered on. The variant according to FIG. 4 can be chosen if a waterproof outsole that is waterproof itself is adhered on. Because of the waterproof sealing enclosure 47, on the one hand, and the waterproof gluing of the outsole to enclosure 47, on the other, water cannot penetrate to the center region of the bottom of the insole 23. This production stage is shown in FIG. 4. This figure also clearly shows that the reactive hot melt adhesive forming the lasting adhesive layer 37 and the reactive hot melt adhesive forming the outsole adhesive 45 forms enclosure 47 for the lasted portion 43, which acts as a waterproof enclosure for portion 43.

[0079] As shown in FIG. 5, the cavity left free of adhesive is filled with a filler 49 in order to form an essentially flat bottom for gluing on of outsole 51 for the shoe structure so produced. Nonwovens, like PES nonwovens, knitted or sole material can be used as filler. In the variant shown in FIG. 5 of a shoe according to the invention, outsole 51 consists of rubber or plastic and is provided with air chambers 53 in the region facing filler 49. These lead to a saving of outsole material, make the outsole and thus the entire shoe lighter and can also lead to softer treading of the shoe on the floor.

[0080] The sealing effect of the sealing enclosure 47 is explained schematically with reference to FIG. 6. Water particles are indicated by small circles and arrows which show the direction of penetration and direction of creep of water within the water-permeable outer material 17 that permits water creep. Water penetrating from the exterior into the outer material can reach upper 15 in the longitudinal direction of outer material 17 and penetrate to the edge of the lasted portion 39 along the lasted end of the upper. Such water is prevented by the waterproof lasting adhesive from migrating into the shoe interior via textile material on the inside of the upper functional layer 21.

[0081] For the case in which the shoe has a water-permeable insole and/or an outsole provided with air chambers 53 open toward the insole, a sealing enclosure 47 is created. Without such an enclosure, water penetrating via the outer material 17 could penetrate up to the air chambers 53, which would not be hampered by the filler 49, since this normally consists of a water-permeable and water-conducting material. Water that penetrated into air chambers 53 would collect there and lead to sloshing noises, an increase in shoe weight and cooling of the insole and consequently to an unpleasant wearing sensation of the shoe.

[0082] As a result of sealing enclosure 47, however, the water can only penetrate to the lasted portion edge, but cannot go further into the shoe interior and/or the air chambers 53.

[0083] Another variant of a shoe according to the invention depicted in FIG. 7 has a structure that is largely identical to the shoe structure depicted in FIG. 5. To this extent the shoe structure depicted in FIG. 7 is not explained again. The shoe structure depicted in FIG. 7 has differences relative to the shoe structure depicted in FIG. 5 to the extent that it has a water- and water vapor-permeable insole 57, for example, for a nonwoven textile material, for example, a web, and is provided with a waterproof, water vapor-permeable outsole 59. Because of this sole structure the shoe depicted in FIG. 7 is also waterproof and breathable in the sole region. This leads to a shoe with particularly good wearing comfort.

[0084] In the variant depicted in FIG. 7 the outsole 59 has an outsole edge region 61 made of rubber or plastic, whose center region is filled with an outsole insert 63 made of a water- and water vapor-permeable material, for example, leather. A waterproof, water vapor-permeable sole functional layer 65, preferably also made of ePTFE, is situated on the outsole insert 63 on the side facing insole 57. As schematically shown in FIG. 7, the sole functional layer 65 extends on its outer edge in the direction of the outsole periphery so that it comes to overlap between the sealing enclosure 47 and the sole functional layer 65. For this reason, water cannot penetrate to the filler and thus insole 57 either via the last region 35 or via the outsole insert 63. The shoe interior is fully protected from penetration of water with maintenance of breathing activity in the entire shoe region.

[0085] During use of an outsole that consists entirely of water-permeable material the sole functional layer 65 can extend to the peripheral edge of the outsole.

[0086] The sole functional layer 65 can be constructed with the same materials as the upper functional layer, i.e., with ePTFE, PU, polypropylene or polyester.

[0087] Still another variant of a shoe according to the invention is depicted in FIGS. 8 to 11 in different production phases. In this variant, an outer material laminate 67 is used, which contains both an outer material, for example, made of leather or textile, and an upper functional layer. The inside of the outer material laminate 67 is lined with a liner 69, which possesses no functional layer. Since the liner 69 need not be sealed, it is cut back in the depiction in FIG. 8 essentially to the bottom of the insole 23 so that the bead-like lasting adhesive 25 comes to lie in the angle between the bottom of the insole 23 and the inside of the outer material laminate 67.

[0088] Otherwise the shoe structure depicted in FIG. 8 coincides with the shoe structure depicted in FIG. 1 and is not further explained here.

[0089] According to the production phase depicted in FIG. 3, FIG. 9 shows the shoe structure of FIG. 8 after the process step of lasting. According to FIG. 10 reactive hot melt adhesive is applied as outsole adhesive 25 on the bottom of the lasting region 43 and the bottom of the insole 23, preferably by spraying. The reactive hot melt adhesive applied as lasting adhesive 25 and the reactive hot melt adhesive applied as outsole adhesive 45 are again joined to a waterproof sealing enclosure 47 that seals the last area 35. According to FIG. 11, a filler 49 is introduced into the cavity remaining within the edge of last area 39 and an outsole 51 made of rubber or some other type of plastic is adhered onto the bottom of the last margin area 43 and the bottom of filler 49. The filler 49 can also be formed by outsole material.

[0090] In the shoe structure depicted in FIG. 11 the insole 11 again consists of waterproof material. As in the second variant depicted in FIG. 7, however, in this third variant a water-permeable insole can again be combined with a waterproof, breathable outsole.

[0091] FIG. 12 shows a section of a sole structure in a schematized, enlarged two-dimensional depiction with lasting adhesive 37 in the form of reactive hot melt adhesive reacted by three-dimensional crosslinking of molecular chains. The three-dimensionality of crosslinking arises owing to the fact that the molecular chains of the reactive hot melt adhesive crosslink also in the third dimension not visible in FIG. 12 (perpendicular to the surface of the drawing) in the manner depicted for two dimensions. This leads to a particularly strong protection against penetration of water into the adhesive.

Claims

1. Footwear comprising:

a) an insole with an insole bottom;

b) an upper which is constructed with an outer material;

c) a waterproof upper functional layer, which forms a part of the upper and at least partially lines the outer material of the upper on its inside, particularly in the end region of the upper;

d) in which the upper has an end region in the lasting margin area which is adhered to the insole bottom;

e) and an outsole which is adhered to the bottom of the lasted margin area;

f) wherein the lasting adhesive is a reactive hot melt adhesive which is waterproof in the reacted state.

2. Footwear according to claim 1, in which the outsole is adhered by a waterproof reactive hot melt adhesive.

3. Footwear according to claim 2, wherein the reactive hot melt adhesives form an enclosure that encloses the end region on the sole side of both the outer material and the upper functional layer.

4. Footwear according to claim 2, in which the lasting adhesive and the outsole adhesive consist of the same reactive hot melt adhesive.

5. Footwear according to claim 1 or 2 wherein the reactive hot melt adhesive has been moisture cured.

6. Footwear according to claim 1 or 2 wherein the reactive hot melt adhesive is selected from the adhesive groups consisting of polyurethane hot melt adhesives and condensation resins.

7. Footwear according to claim 1 or 2 wherein the reactive hot melt adhesive is a PU reactive hot melt adhesive that is constructed with blocked isocyanate.

8. Footwear according to claim 1 or 2 in which the reactive hot melt adhesive contains a thermoplastic.

9. Footwear according to claim 1 or 2, in which the upper functional layer is water vapor-permeable.

10. Footwear according to claim 1 or 2 in which the functional layer is porous polytetrafluoroethylene.

11. Method for production of footwear, that has:

a) an insole with an insole bottom:

b) an upper which is constructed with an outer material and has an end region on the sole;

c) a waterproof shaft functional layer, which at least partially lines the outer material of the upper on its inside and has an end region on the sole side;

d) in which the upper has a lasting region at its end; and

e) an outsole;

wherein the process comprises:

f) adhering the upper end region to the insole bottom by means of lasting adhesive in which a reactive hot melt adhesive is used as lasting adhesive;

g) adhering an outsole to the bottom.